Texas Coral Reefs [1 ed.] 9781603442763, 9781585446339

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Texas Coral Reefs

Number thirteen

Gulf Coast Studies Sponsored by Texas A&M ­University–Corpus Christi John W. Tunnell Jr., General Editor foreword

Texas Coral Ree f s

J e s s e C a nc e lmo Foreword by Sylvia Earle

Texas A&M University Press College Station

Copyright © 2008 by Jesse Cancelmo manufactured in China by everbest Printing Co., through Four Colour imports All rights reserved First edition this paper meets the requirements of ANSi/NiSO Z39.48–1992 (Permanence of Paper). binding materials have been chosen for durability.

Cover photo shows schooling creolefish at the Madracis coral formation at Stetson Bank

Library of Congress Cataloging-in-Publication Data Cancelmo, Jesse. texas coral reefs / Jesse Cancelmo. — 1st ed. p. cm. — (Gulf Coast studies ; no. 13) includes index. iSbN-13: 978-1-58544-633-9 (cloth : alk. paper) iSbN-10: 1-58544-633-5 (cloth : alk. paper) 1. Coral reef biology—mexico, Gulf of. 2. Coral reef ecology—mexico,Gulf of. 3. Coral reefs and islands—mexico, Gulf of. i. title. Qh92.3.C67

2008

578.77'8909764—dc22 2007026472

foreword

To Ted Wimprine, my good friend and dive buddy, with whom I have made many dives and shared a passion for exploring the Flower Garden Banks and Stetson Bank reefs.

foreword

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foreword

Contents

Foreword, by Sylvia Earle

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Preface

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Acknowledgments

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Introduction, by Quenton Dokken

1

Chapter 1 East and West Flower Garden Banks: Twin Jewels in the Gulf Chapter 2

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Stetson Bank: A Macrophotographer’s

Bonanza

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Chapter 3

Geyer Bank: A Tiny Splendor of Life

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Chapter 4

Sonnier Bank: A Louisiana Treasure

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Chapter 5

Artificial Reefs

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Index

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foreword

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Foreword

T

he coastal waters of Texas have their charms, with green marshes, sandy beaches, and bordering forests that are vital havens for migrating birds and other wildlife, as well as for millions of people who are attracted to the ineffable lure of the sea. But coral reefs? Who knew that Texas is blessed with coral reefs that host clouds of brilliant tropical reef fish, big barracuda, giant sponges, crimson starfish, mammoth mantas, and hundreds of hammerhead sharks? For several decades, savvy divers, marine scientists, offshore oil workers, and fishermen willing to venture south of Texas shores have been tuned in to one of the ocean’s best kept secrets: the northern Gulf of Mexico’s undersea range of coral-crowned minimountains referred to by geologists as “topographic highs.” Now the world can share the view and become intimately, if vicariously, acquainted with the amazingly rich diversity of life that prospers in the clear, warm, sapphire waters offshore in the northern Gulf, thanks to Jesse Cancelmo and his luxuriously beautiful volume celebrating the submerged blue face of Texas. I was amazed and more than a little skeptical when I first heard from scuba divers in 1972 about the existence of an area referred to as the Texas “Flower Gardens.” I had spent twenty years exploring the coastal waters of the Gulf of Mexico and had dived the reefs of the Florida Keys, ventured among the Ten Thousand Islands northward to Tampa Bay and beyond into Florida’s Big Bend region,

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where marshes and sea grass meadows extend seaward for many miles. With Navy divers from Panama City and researchers from Alabama, Mississippi, Louisiana, and Texas, I had spent hundreds of hours submerged, exploring rocky outcrops, jetties, and parts of the Gulf’s growing “steel archipelago” of offshore oil rigs. Nothing along the shores of the northern Gulf appeared suitable for coral reefs, largely owing to the flow of freshwater and many tons of sediment flowing from the Mississippi and numerous other rivers, as well as near-shore temperatures that in summer range hotter than corals generally can endure to much cooler than is hospitable for them in the winter. The nearest reefs to Texas, I thought, were those in Mexico, hundreds of miles to the south. I had not reckoned on the now well-known Loop Current that streams northward between Yucatan and Cuba far into the Gulf, sweeping clear, warm water loaded with tropical marinelife in a wide swath across the northern Gulf, before bending south along the west Florida coast, exiting through the Florida Strait, and joining the powerful Gulf Stream bordering eastern Florida and the Bahamas. Given the Loop Current’s character and its pathway, it is no wonder that the offshore reefs of Texas look like a healthy slice of the Caribbean! The definitive 1954 reference for the region, the Fishery Bulletin 89, “Gulf of Mexico, Its Origin, Waters and Marine Life,” notes the existence of “numerous submerged hills rising above the seafloor near the outer edge of the continental shelf” in the northern Gulf, and remarks that “corals have been dredged from the tops of a few of these knobs or domes,” but no photographs demonstrate the findings, and under­water photography generally was then in the pioneering stages of development. My own attempts to document the nature of life in the Gulf in the 1970s are replete with blurry black-and-white images, coupled with tantalizing notes about a “Caribbean influence” possibly reaching much farther north than had previously been suspected. In striking contrast, consider the images and findings in this volume. From close encounters with jawfish two inches long to forty­ foot whale sharks, Cancelmo shares his view—and insights—into the true nature of what the creatures who live in the Gulf have known all along. The arc of undersea islands a hundred or so miles



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offshore in the northern Gulf harbor a wealth of life that is both beautiful and critical to maintaining the vitality of the waters of this part of the ocean. Reviewing this book caused me to reflect on my first glimpse of the Flower Gardens in 1990, an official “site visit” while serving as Chief Scientist of the National Oceanic and Atmospheric Administration (NOAA). Underwater one hundred miles south of Galveston, the culminating joy of years of anticipation came in a rush—but with it, a sobering jolt of reality. Protected for millennia by their remoteness and inaccessibility, what we now know and love about these reefs will endure if and only if those of us who know—and care—will take actions needed to ensure protection. In fact, concerns about losing these special reservoirs of life, spawning areas for fish and invertebrates, feeding areas for pelagic species, shelter for one and all, led to protection for two of the most notable places, the East and West Banks of the Flower Gardens in 1992 as a National Marine Sanctuary, with Stetson Bank added in 1996. In recent years, I have returned to the northern Texas reefs many times as a diver, sometimes driving little submarines, occasionally exploring using cameras on remotely operated vehicles, but always with a combination of pleasure at what is there and dread over signs of decline. At the same time that awareness of these treasured undersea islands and their importance to the nature of the Gulf began to dawn on me and other Gulf-watchers, worrisome signs of degradation and loss also began to appear. From the time early in the twentieth century, when a few daring fishermen discovered and named the Texas Flower Gardens, to the early twenty-first century, when noxious “dead zones” near the mouth of the Mississippi River made worldwide headlines, unprecedented changes have taken place. Just as new technologies began making it possible to understand the ocean as never before, new technologies also made it possible to exploit as never before. Moreover, the demands of expanding human population, especially in coastal regions, began stressing the ocean and its wildlife beyond anything known in history. In addition to overarching climate change issues and increased fishing pressure using such destructive techniques as bottom trawls, gill nets, and long lines draped with thousands of baited hooks, onshore foreword

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and offshore pollution have had a profound impact on all of the Gulf of Mexico, including the northern coral reefs featured here. But there is plenty of reason for optimism, as evidenced by this volume. Philosophers say that we will protect what we love, and there is much to love about the coral reefs of Texas. Once safe, owing to their remoteness and because few people knew of their existence, their survival in this century and beyond will require conscious care, care inspired by the realization of their value to all of us, now and forevermore.

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foreword

—Sylvia Earle

Preface

I

discovered the magic and splendor of the underwater realm more than thirty-five years ago. In 1969 I was vacationing in Bermuda and made a resort scuba dive on a coral reef. It was a life-changing experience. The fish, the corals, the color, the motions, and the emotions were unlike anything I’d seen or felt before. Considering that Bermuda touts the northernmost coral reefs in the Western Hemisphere, it’s uncanny that I ended up in Houston, Texas, nearby the Flower Garden Bank reefs that are the northernmost coral reefs in the continental United States. After graduating from college I landed a job with a Bermuda commercial diving company and lived there for a year. Bermuda’s coral reefs were inspirational. They stoked my newfound passion for diving and underwater photography. After getting my fix of island living, I returned to my Pennsylvania hometown and spent a couple of years honing my diving skills on the World War II shipwrecks off the New Jersey coast before moving to Houston in 1976. A year later I made my first trip to the Flower Garden Banks, roughing it on a slow clunker of a dive boat operating out of Sabine Pass. It seemed like it took forever to get there. The boat was spartan by today’s standards, and the overnight trip was more like camping out than staying in a comfy floating hotel. Since then I’ve made hundreds of trips to the reefs and rigs in the northwestern Gulf of Mexico. And since then, Texas dive boats have come a long way— comfortable bunks with pillows and sheets, reliable air conditioners,

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camera tables, Nitrox supply, onboard naturalists, and more—but my passion for diving in this area hasn’t changed. Also unaffected by time is the condition of the reefs. They are few, relatively small, and far between, but over time these Texas and Louisiana gems continue to thrive, largely unaffected by coastal or industrial development. It helps considerably that the Flower Garden Banks and nearby reefs are naturally protected from runoff and excessive human pressures by one hundred miles of ocean. Even so, it’s a surprise to most divers that the coral reefs in the northwestern Gulf of Mexico are by far the most dense and healthy of any reefs in the continental United States. Who would ever imagine that less than two hundred miles from the fourth largest city in the United States, divers can visit coral reefs thriving with tropical marine life and have a chance to encounter a whale shark, a manta ray, or schooling hammerhead sharks? And if that’s not enough, the reefs’ annual spectacle of mass coral spawning attracts divers from around the world. Nature’s celebration of coral reproduction occurs predictably in the evenings seven to ten days after the August full moon at the East and West Flower Garden Banks. As of 2007, the identification count at the Flower Garden Banks National Marine Sanctuary includes twenty-three species of coral and 280 species of fish. The fish count includes twenty species of sharks and rays. In 1990 the Gulf Reef Environmental Action Team (GREAT) enlisted me to serve on its board of directors. Gary Rinn, a pioneer of sport diving in the Texas Gulf region, founded this nonprofit environmental organization the previous year, dedicated in part to counter the increasing threat of anchor damage to the fragile coral reefs. In 1990 GREAT members and volunteers installed twelve permanent boat moorings and buoys at the East and West Flower Garden Bank reefs. The moorings were installed by drilling pairs of holes into dead coral at high points on the reef and packing concrete in the holes to anchor stainless-steel inverted U-bolts. Shackles, polyester line, assorted hardware, and surface buoys completed the installation. Other volunteers did the drilling while I documented the entire process on film. The moorings allow boats to safely tie up to the reefs without causing anchor damage to the fragile live corals. GREAT later sponsored a three-year environmental monitoring

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and mapping program at Stetson Bank. The monitoring program included fish counts and video monitoring to ascertain the health of the reef. In the early to mid-1990s I worked many spring and summer weekends as a boat divemaster on two of Gary Rinn’s dive boats. I logged hundreds of dives at the Flower Garden Banks and Stetson Bank. The East and West Flower Garden Banks and Stetson Bank are only three of the dozens of reefs scattered along the edge of the continental shelf from the Mississippi Delta to the Mexican border. Most of the banks are too deep for recreational diving. The Flower Garden Banks, Stetson Bank, and Louisiana’s Sonnier Bank are all well within recreational dive limits, but there are a few other deeper banks that are just barely within the recreational depth limits. For the past six years I’ve organized and led numerous custom-dive charter trips to the Flower Garden Banks National Marine Sanctuary, Sonnier Bank, and two of the lesser known deeper banks—Geyer Bank and Bright Bank. As a point of clarification, although Sonnier Bank is clearly a Louisiana reef, I’ve devoted chapter 4 of Texas Coral Reefs to Sonnier Bank because of its sensational natural beauty and proximity to Texas, and because it is a sister reef to Texas’s Stetson Bank. I’m an explorer at heart and am always in search of new dive sites and challenges. My logbook entries include the Andrea Doria off Long Island, the USS Monitor off Cape Hatteras and the USS Wilkes-Barre off Key West. But as much as I love to explore wrecks and reefs and trot around the globe to experience new sites and fascinating marine animals, I’ll forever have a bent for further adventures in my own backyard. There’s just so much to see out there! Jesse Cancelmo Houston, Texas www.cancelmophoto.com

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Acknowledgments

I

have been writing about the Flower Garden Banks and Texas reefs since the early 1980s. The list of people who have supported my efforts is a long one. If I attempted to cite them all I’d surely leave someone out. But there are six individuals who stand out for the special assistance they provided me along the way. To them I give my heartfelt thanks: Dr. Steve Gittings, science coordinator for NOAA’s National Marine Science Program; Gary Rinn, founder of the Gulf Reef Environmental Action Team and former dive-boat operator; Captain Randy Widamen; Emma Hickerson, research coordinator at the Flower Garden Banks National Marine Sanctuary; Doug Weaver, marine biologist and GIS specialist at the Flower Garden Banks National Marine Sanctuary; and Greg Boland, marine scientist for the Minerals Management Service. And let me also acknowledge Dr. Quenton Dokken for his support and eagerness to write the introduction to this book.

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Texas Coral Reefs

Introduction Quenton Dokken

T

he Gulf of Mexico is a vast body of water with a rich history, geologically and anthropologically. At one time, the boundaries of the Gulf of Mexico reached across northern Mexico and into the territories of Arizona. Ancient societies of Native Americans depended on its bays and estuaries for sustenance. Today, as technology has allowed us to explore and discover the character of the Gulf of Mexico from its shallowest waters to its deep abyssal plains, modern explorers, scientists, anglers, and recreational divers have become fascinated by its natural and artificial reefs. From the nearshore temperate waters to the deep offshore tropical waters of the Gulf, these reefs support diverse and dynamic communities of the Gulf’s living collage of marine creatures. As a new sport diver in 1969 and a marine science student in the mid-1970s, I heard rumors of vibrant coral reefs with colorful tropical fish, giant manta rays, and other exotic creatures off the Texas coast. Until then, I associated coral reefs with tropical islands and beaches washed in warm, clear water. Being a lifelong resident of the Texas coast, I was accustomed to seasonally cold-to-hot turbid coastal waters but knew little of the distant offshore waters of the northern Gulf of Mexico. Stories of the “Flower Garden” coral reefs were almost too incredible to believe. Then, in 1974, Thomas Bright and Linda Pequegnat published Biota of the West Flower Garden Bank, the most extensive written description of the Flower Garden Banks’ coral reefs to that time. Beginning in the late 1960s, Dr. Bright led expeditions to the banks and returned with biological collections and photographs of this



biological anomaly 110 miles south-southeast of Galveston in the deep waters of the northwestern Gulf of Mexico. A tropical coral reef did in fact exist off the Texas coast. My first trip to the Flower Gardens was around 1985. Going to the “Gardens” was not then or now a leisurely day trip but rather a challenging multiday expedition. At best, boats require eight hours of travel to reach the Gardens, usually running bow into choppy seas and a southeast wind blowing onshore from the southern Gulf. That first trip was aboard an offshore supply boat idled by a dramatic slowdown in the offshore oil and gas industry. Looking for alternative income, the operators of this Louisiana-based vessel offered a sport-diving charter to the Gardens. Sleeping arrangements were a bedroll on the floor, dining options were whatever you brought with you, and diving support was “every diver for himself.” Heedless of the spartan live-aboard conditions, the divers on this voyage were in high spirits in anticipation of the adventure ahead. On that first dive we joined the ranks of those few who had dived the Flower Garden Banks’ coral reefs. The coral formations were extensive. Colorful sea creatures darted in and out of the nooks and crannies of the reefs, and giant manta rays glided gracefully through the warm, clear waters above the corals. Since then I have made scores of trips to the Gardens and over a thousand dives on other reefs, natural and artificial, in the Gulf of Mexico and Caribbean Sea. Still, the excitement of discovery on that first trip to the Flower Garden Banks’ coral reefs remains fresh in my memory. The Flower Garden Banks and smaller reefs along the edge of the outer continental shelf in the Gulf of Mexico are a unique and important natural resource. They are relatively isolated from shoreside impacts by distance and water depth. They harbor a rich reserve of biological diversity and productivity. In an age when coral reefs around the world are being lost at alarming rates, the biological and ecological value of the Flower Garden Banks is increasing. Many of the living reefs of the Florida Keys and of Mexico have been lost due to the impacts of human activity. The islands of the Caribbean Sea are witnessing significant losses of coral reefs. Some scientists have suggested that living coral reefs could be rare if not extinct before



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the end of the twenty-first century. Just as the rain forests of the tropics are under assault from humans, so too are the coral reefs of the world. Through the efforts of the National Oceanic and Atmospheric Administration and the Minerals Management Service, along with a number of universities and consulting companies, the Flower Garden Banks have been continuously monitored and studied since Dr. Bright’s initial expeditions more than thirty-five years ago. Located in the middle of the most active and concentrated offshore oil and gas production field in the world, these reefs are thriving. They boast the greatest coverage of living coral, about 50 percent, of any reefs in the Gulf of Mexico and Caribbean Sea. One might well ask why these reefs have not succumbed to the ravages of human impacts like the reefs in other parts of the Gulf of Mexico and Caribbean Sea. Reef-building corals have two main environmental requirements: warm water, generally 18°–30°C (about 65°–86°F), and shallow, clear water able to transmit adequate sunlight to the coral polyps to support photosynthesis. The coastal areas of the northern Gulf of Mexico are characterized by temperate conditions where seasonal temperature extremes exceed the lower limits of reef-building corals and water conditions are turbid due to the shallow, gently sloping character of the continental shelf. Wind and currents maintain sediment in suspension, clouding the water and limiting the penetration of sunlight. In contrast, moving offshore away from the coast, the waters of the northern Gulf of Mexico take on a tropical character. The upper areas of the water column stay within the temperature limits of reef-building corals, and surface waters are unclouded by bottom sediments, allowing sunlight to penetrate brightly enough to support coral growth to approximately 150 feet. The seabed around the Flower Garden Banks is about four hundred feet, too deep for reef-building corals. However, geological formations known as salt domes extend from the seabed upward to within approximately seventy feet of the sea surface. It is on top of these domes that coral polyps settled about ten thousand years ago to begin building the Flower Garden Banks’ coral reefs and other smaller reefs in the northwestern Gulf of Mexico. introduction



Coral polyps, small colorless creatures with tentacles, build massive coral reefs in tropical waters around the world. As an integral part of its physiology, within each coral polyp are algal cells known as zooanthallae. It is the zooanthallae that require sunlight to complete photosynthesis, hence the need for clear water through which sunlight can be transmitted. It is the zooanthallae that give corals their characteristic colors. The coral polyps extend their tentacles, usually at night, to capture small particles of plankton floating by with the currents. This plant and animal matter is digested by the polyps, creating waste products that the zooanthallae consume during the process of photosynthesis. The relationship between the polyp and the zooanthallae is truly a symbiotic one. When stressed, the coral polyps expel the zooanthallae, leaving the coral colony white in color, a condition called “bleaching.” The bleaching event can be partial or complete and it can be fatal to the colony if the stressor agent persists. Chronic and catastrophic bleaching events have decimated coral reefs around the world. At the Flower Garden Banks, bleaching events usually occur in mid- to late August when water temperatures are at the highest. High temperatures are a recognized stressor of coral polyps. These events have been typically short lived, two to three weeks, and have not been fatal to the colonies. Sea urchins are “keystone” organisms in a coral reef ecosystem. They are herbivorous grazers that scour reef rock of algae that can overgrow the coral polyps and colony if left unchecked. In the early 1980s a viral disease of an unknown origin wiped out the sea urchins on the reefs of the Gulf of Mexico and Caribbean Sea. Many shallow-water reefs were soon overgrown and killed by unchecked algal growth. This overgrowth did not happen at the Flower Garden Banks, primarily due to increases in the populations of herbivorous parrotfish and other grazers that have kept the algae in check. To this day, the urchin populations have not fully recovered at the Flower Garden Banks, but the Flower Gardens remain healthy and productive. Disease has become a prominent threat to coral reefs. White plague, black band, yellow blotch, and a host of other diseases of corals have decimated reefs around the world. Yet at the Flower



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Garden Banks to date, disease has had little effect on the health and sustainability of the reefs. Monitoring studies have indicated that generally less than 1 percent of the corals show any symptoms of disease. Black band, although common in the Caribbean Sea, has not occurred at the Flower Garden Banks. Diseases of corals and the resistance of corals to disease are not yet well understood. Scientists are studying how diseases are transmitted and what makes corals susceptible to disease, but they do not yet have a clear picture of how diseases may affect the Flower Garden Banks in the future. Hurricanes have a natural impact on the longevity of the corals at the Flower Garden Banks. During Hurricane Rita in 2005, large coral colonies were broken from their base and turned upside down by the force of the waves and currents associated with the storm. Once inverted, the coral polyps soon die. Hurricanes have been roaring above the Flower Garden Banks for thousands of years, and the reefs have always been able to recover. But now the combined affect of natural and human impacts has been growing, and it is possible that someday the reefs of the northern Gulf of Mexico will not be able to compensate for the collective impacts of nature and humans. Within the scientific and recreational dive communities, exploration and study of the Flower Garden Banks sparked substantial interest in the other banks of the northern Gulf of Mexico—among them Bright Bank, Sonnier Bank, Geyer Bank, and Stetson Bank. Although they were known to exist, we did not know much about the biological communities they supported. In the northern Gulf of Mexico, only the Flower Garden Banks are truly “coral reefs.” Although all the other banks support reefbuilding corals, these organisms are not the dominant creatures. Like the Flower Garden Banks, the geological foundations of many of these “noncoral” reefs are protruding salt domes topped by clay and sandstone, and the biological communities of these reefs are just as spectacular. Modern societies have had profound impacts on the habitats and marine life of the Gulf of Mexico. Usually these impacts have been negative, but one positive impact has been the development of artificial reefs. Fishermen in some parts of the world have used introduction



artificial reefs to enhance fishing success for two thousand years, but artificial reefs were not given much attention in the Gulf of Mexico until the last fifty years. With the placement of the first oil and gas production platform in marine waters off the coast of Louisiana in 1947, it was soon observed that the structures of the platform provided a hard surface for sessile organisms (e.g., algae, barnacles, and clams) to attach to and that fish were attracted to this “reef” structure. As these structures moved from the shallow nearshore waters to the deep, clear offshore waters, awareness of their value increased. They became prime fishing spots, and now 80 percent of all recreational fishing trips in the northern Gulf of Mexico go to platform reefs. When I started my diving career beneath platforms off south Texas in the late 1960s, offshore technology was limited and platforms were rarely more than twenty miles from shore. In the 1970s, oil and gas producers began installing platforms farther from shore in deeper waters that were more tropical in character than the nearshore temperate waters of the Gulf of Mexico. Today, there are thousands of these platforms in the northern Gulf of Mexico, some more than 150 miles from shore in water more than one thousand feet deep. Platform structures affected the ecology of the Gulf of Mexico generally in two ways. By significantly increasing the “hard substrate” exposed to ocean currents, the biomass of the sessile communities of the Gulf of Mexico increased. And by providing “islands” of refuge for passively and actively migrating organisms, the character of the zoogeography of the Gulf of Mexico was altered. For sport divers, these dynamic reefs have been a windfall. The vast majority of the sport diving in the northern Gulf of Mexico is done at platform reefs, particularly off Louisiana and Texas. Through the nature of their design, oil and gas platforms create reef environments very different from those of natural reefs resting on the seabed. Platform reefs are vertical structures penetrating the surface of the Gulf of Mexico at one end and the seabed at the other. The platform’s legs, along with the diagonal and horizontal support beams, create an intricate reef structure. As you start at the surface and descend, the biological communities change as a result of water



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characteristics such as surface wave energy, oxygen content, sunlight intensity, and temperature. Life at the top is very different from that at the bottom. Our challenge today is to devise and implement management strategies that ensure all Texas reefs remain healthy. Coastal resident and visitor populations are growing rapidly along with the demand for marine resources. At the same time, coastal habitats are being degraded or destroyed at alarming rates. Pollution from the extensive watersheds of the Gulf of Mexico is increasing. We must have productive economies, but we must also have productive ecosystems. A healthy economy and a healthy environment are not mutually exclusive but rather are inextricably linked; both are cornerstones to the high quality of life we desire and strive for. One step toward achieving healthy and sustainable marine resources in the Gulf of Mexico was the creation of the Flower Garden Banks National Marine Sanctuary, which encompasses both the East and West Flower Garden Banks and Stetson Bank. Led by the staff of the Flower Garden Banks National Marine Sanctuary and supported by the Minerals Management Service, efforts have been made to study and intensely monitor the condition of these reefs through the work of scores of scientists and students. Platform reefs present management challenges that have yet to be addressed. Extending above the sea surface, they are easily reached by recreational and commercial fishers. Below the surface, they attract many species of fish prized by anglers and spearfishers. As a result, they make it easier for a larger number of people to catch a greater number of fish. Today’s fishing regulations do not directly address the special circumstances the platforms create. A management tool becoming more in vogue worldwide is the utilization of Marine Protected Areas (MPAs), a designation that restricts the harvest of marine organisms in areas of biological and ecological significance. In theory, this strategy allows breeding populations of marine organisms to exist unmolested and to continuously produce subsequent generations of marine life. The availability of human-made structures from which to build artificial reefs within the boundaries of MPAs could be a key tool to achieving sustainability. I can envision a time when obsolete platform structures introduction



are transported and concentrated in an area designated as an MPA, creating safe haven for species such as red snapper, red drum, and seasonally migrating species such as amberjack and cobia. When I prepared to make my first dive in the nearshore waters of the Gulf of Mexico near Corpus Christi, Texas, I was anxious, excited, and totally ignorant of what I was about to discover. That day set a course for the rest of my life. Over the decades, I’ve been blessed with opportunities to swim with the manta rays and sharks over the banks and reefs of the Gulf of Mexico. I’ve participated in the development and application of new diving technology, including mixed gas, rebreathers, and one-atmosphere submersibles. I’ve seen wonders that relatively few people ever see first-hand. Sharing my offshore adventures have been countless fellow sport divers and marine science students, teachers, and scientists. Included in my list of intrepid companions are the world’s best-known underwater photographers and videographers, whose work has created a lasting vision of the reefs and banks of the northern Gulf of Mexico. As you enjoy the beautiful underwater images of Jesse Cancelmo and read about his fascinating encounters with life under the sea, remember that only through dedicated effort on everyone’s part can we ensure that these reefs remain a living reality forevermore.



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East and West Flower Garden Banks

c h a p t e r one

Twin Jewels in the Gulf

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t’s a miracle of nature that two tiny coral reefs just one hundred miles south of the Texas-Louisiana border ever managed a foothold more than four hundred miles away from the nearest coral reefs in Florida and Mexico. Thanks to the Gulf of Mexico’s Loop Currents, conditions at the Flower Garden Banks are typically Caribbean clear and blue. Warm Gulf Stream currents carry the coral larvae to the tops of the twin undersea salt domes that were pushed toward the surface during the last Ice Age. Credit the sun to penetrate the crystal clear water and energize the algae needed to sustain reef-building corals. Still, it’s almost like magic that these two coral reefs were formed. The West Flower Garden, a shoe-print-shaped coral reef covering no more than one hundred acres, caps a bank that’s five miles long and three miles wide. The East Flower Garden, twelve miles to the east, flaunts a reef cover almost five times that of its twin. Unlike a typical Caribbean coral reef with a mix of branching corals, soft swaying corals, and hard plate and boulder coral species, the reefs at the East and West Flower Garden Banks are covered entirely with hard corals, mostly brain and star varieties. At least twenty-three species of corals are found there. With depths ranging from 60 to more than 130 feet, dive sites appear as expansive coral meadows filled with massive boulder-shaped coral heads, forming a rugged seascape. The enormous, closely spaced coral heads have undersides covered with strawberry-, mustard-, and olive-colored encrusting sponges. Some of the smaller coral heads appear to be sculpted, with narrow stalks and caps that resemble toadstools. Many of the massive stony formations are studded with brain and star coral heads and

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Location of the East and West Flower Garden Banks, Stetson Bank, Geyer Bank, Sonnier Bank, and the Liberty Ship artificial reef in the Gulf of Mexico. “HI 389” is the gas platform High Island 389. Courtesy of Doug Weaver, Flower Garden Banks National Marine Sanctuary.

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are riddled with holes and small caverns that make perfect habitats for reef fish. Bluehead wrasse, butterflyfish, yellowfin grouper, sharpnose puffers, and queen angelfish are a few of the more than 280 species of fish that make the Flower Gardens their home. Only sparse patches of sand interrupt the reef’s healthy cover of coral. The narrow, sandy alleyways between the coral heads host yellowhead jawfish, sand tilefish, yellow goatfish, and other bottom dwellers. Schools of blue and brown chromis and reddish-colored creolefish hover over the coral heads while squadrons of huge, silvery horse-eye jacks rush through the reef. Meanwhile, near the dive boat barracudas assemble in formations below the weighted safety lines, acting like sentries for the returning divers. After it gets dark, red night shrimp accent the reef with their tiny glowing eyes, slipper lobsters crawl across the coral tops, and the normally skittish creolefish lie as still as the sleeping parrotfish. chapter one

A Brief History of Moorings at the Sanctuary The salt formations beneath the coral cover originated more than 160 million years ago, during an era when dinosaurs dominated the earth. Over time, sediments covered the salt, and certain pockets of the salt formations were pushed upward, forming domes. Scientists estimate the coral development on the top of the domes began at least ten thousand years ago. It’s likely that currents in the southwestern Gulf delivered coral larvae from Mexican reefs at Campeche Bank. The colorful sponges and corals were discovered by snapper fishermen in the 1890s and then rediscovered by scuba divers in the 1960s. In the early 1970s, while oil and gas exploration activities increased dramatically in the northern Gulf of Mexico, government lease stipulations afforded only limited protection to the Flower Gardens. Efforts underway at that time to further protect the Flower Garden Banks as a marine sanctuary were stymied by governmental bureaucracy. Although the oil and gas developments first appeared as the biggest threat to the reefs, the real problem proved to be from the indiscriminate anchoring of certain tankers and large vessels that caused serious damage to sections of the live reefs. Recreational use of the reefs raised additional concerns about damage caused by anchors and anchor chains. In 1990 a group of sport divers and marine scientists led by the Flower Garden Banks sport-diving pioneer Gary Rinn took matters in their own hands and installed twelve permanent boat moorings at the two Flower Garden Banks’ reefs. The moorings protect the reefs by allowing divers and fishermen to secure their boats without using anchors. In 1992 the Flower Garden Banks were designated the nation’s tenth national marine sanctuary. This precious habitat is now protected from commercial fishing, commercial discharges, and boat anchoring. Added protection was afforded to the resources of the sanctuary in 2001, when the International Maritime Organization adopted language in their regulations that designated the Flower Garden Banks National Marine Sanctuary as the world’s first international “no anchor” zone.

east and west flower garden banks

A diver makes a sunrise entry at the Flower Garden Banks National Marine Sanctuary.

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A diver swims alongside a colorful coral head at the East Flower Garden Bank’s reef.

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With the curiosity of a cat, barracudas often follow divers through the reef but usually keep a safe distance when confronted.

Red night shrimp, Rhynchocinetes rigens, are seen all over the Flower Garden Banks during night dives. These shy creatures hide in holes and crevices during the day.

Like other parrotfish at the Flower Garden Banks, redband parrotfish sleep at night on the reef.

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Schooling creolefish hang over a large formation of boulder star corals at the East Flower Garden Bank’s reef.

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Coral Colonies at the East and West Reefs

The blue angelfish is one of the few fish on the reef that feeds almost entirely on sponges.

One could make a case that the largest animals in the world are our coral reefs. They are expansive masses of animal life made up of individual coral polyps, each one the size of a pea. The polyps grow side by side, each having a tube-shaped body with one end secured to the limestone base and the other open. The open end features a mouth surrounded by tentacles that the polyp uses to sting and trap food. Most people know that living corals are part of the animal kingdom, but few know they coexist with zooxanthellae or algae. Embedded in the coral tissues, the zooxanthellae use sunlight to photosynthesize sugars and provide the coral polyps with their main source of nutrition. The algae also give the corals their greenish­-brown coloration. The East and West Banks are nearly

A yellowhead jawfish hovers above its bottom hideout. The male jawfish incubates the female’s eggs in its mouth.

Similar to creolefish, creole wrasses hover over the reef in schools during the day and rest on the reef at night.

Diver Vivian Dunlop swims around a brightly colored coral head at the East Flower Garden Bank’s reef.

identical twins when it comes to the coral formations and biological community. Geologists have determined that the West Flower Garden Bank is older than the East. Another difference is reef depth. The reef top at the East Bank is five to ten feet shallower than that at the West Bank. But the two reefs share a preponderance of similarities. At both banks, the green, brown, and yellow coral-cloaked boulders fill the reef-top scenery in all directions. Most are covered with star and brain corals whose polyps form circular or convoluted patterns. By far the most dominant corals are the three boulder star corals, Montastraea annularis, Montastraea franksi, and Montastraea favedata, which collectively account for more than half the coral cover. The symmetrical brain coral (Diploria strigosa), the mustard hill coral (Porites astreoides), and the great star coral (Montastraea cavernosa) are the next three most prevalent coral species. At both reefs there is a conspicuous absence of branching corals such as staghorns and elkhorns, and there are no sea whips or fan corals on the reef tops. There are twenty-seven species of sponges, more than sixty species of crustaceans, and more than six hundred species of mollusks on the reefs at the East and West Flower Garden Banks. The populations of fish there are quite healthy, but the species count of 280 is lower than what is typically found on a Caribbean reef. The distance from shore is a blessing for both banks. It provides a protective ocean buffer that few reefs in the Caribbean have. Disturbance from people and coastal development is minimal. Other than the travel time for divers, the only limitation of the distance from shore is the more difficult and costly monitoring and enforcement. .

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At left: A cloud of creolefish hovers over a massive formation of tube sponges at the West Flower Garden Bank’s reef.

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A pair of creole wrasses swims in front of a mushroom-shaped coral head at the West Flower Garden Bank’s reef.

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An adult queen parrotfish swims over a formation of boulder star coral at the East Flower Garden Bank.

Photographer Isabelle Guillen approaches a giant barrel sponge at the West Flower Garden Bank.

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Mass Spawning Event On an August evening in the early 1990s a diver surfaced early from a dive on the East Flower Garden Bank and complained that the visibility had suddenly “gone to hell!” He explained that there was so much crud in the water that it looked like an underwater snowstorm. He didn’t realize he had witnessed an event marine scientists describe as “mass coral spawning.” The reef was spewing so many male and female coral gametes into the water column that it created a virtual undersea blizzard. Every year, seven to ten days after the August full moon, and sometimes in September, coral colonies spawn en masse at the East and West Flower Garden Banks. The reefs’ corals begin showing unusual signs just before dusk. The individual pea-sized star coral

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Mass coral spawning occurs every August, seven to ten nights after the full moon.

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A brain coral head explodes with spawn, creating a snowstorm of spawn in the water column.

Every summer on a predictable night and hour, male Montastraea cavernosa star corals discharge wispy streams of “smokelike” sperm.

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polyps puff up like tiny bulbs ready to burst. After sunset, the polyps continue to swell. Male M. cavernosa star corals begin “smoking” as they discharge wispy streams of sperm into the water column. Female great star coral colonies jettison tiny spherical egg sacs like popcorn poppers. Meanwhile, rows of tiny pinkish-white BB-size egg bundles gradually emerge from the valleys between the brain corals’ convoluted ridges. On cue, like magic, thousands of miniature packets of eggs and sperm explode from the reef in a synchronized celebration. Some observers liken the scene to an upside-down snowstorm. During the height of the major eruptions, the normally Caribbean-clear water column transforms into a blinding blizzard of spawn. But unlike snow, the tiny packets rise slowly from the bottom to form a thick mat of biologically active gametes on the surface. The floating mat is where the fertilization occurs. Waves break apart the bundles of seeds, causing a distinct scent of musk. The surviving larvae drift in the currents for days or perhaps weeks. They eventually settle to the bottom. The lucky ones attach to a hard surface where they can grow and colonize. Back on the reef the night’s darkness provides protection from plankton-eating predators. Yet other reef residents also join in the sexual melee. Brittle stars eject bright red eggs and stringy streams of sperm. Christmas tree tube worms release sperm, and cowfish, bluehead wrasses, black durgeons, and brown chromis go absolutely bonkers during the spawn. Barrel sponges and encrusting sponges also join the reproductive frenzy. Whether by chance or by design, the spawning event also coincides with the annual peak in water temperatures and occurs during the period of the year having calmest seas and best visibility. It’s also worth noting that the slack tides during the half-moon make for weak currents that minimize scattering on the surface. These factors may suggest a natural mechanism to maximize successful reproduction.

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A red-ridged clinging crab, Mithrax forceps, hides during the day but emerges from the reef at night.

Ruby brittle stars are nocturnal creatures that hide by day in the cracks and holes of the reef.

Individual creolefish sleep on the reef at night, but during the day they hover over the reef in massive schools.

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A “sleeping” princess parrotfish on a night dive at the East Flower Garden Bank’s reef.

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Rays and Sharks When it comes to manta rays, first impressions can be deceiving. As they appear from a distance, against a deep blue backdrop, they can look almost menacing—like dark stealth creatures. But as mantas get closer they seem more like giant, friendly birds gliding through the reef in slow motion with wings in full extension. Their prominent “devil horns” are actually frontal fins, an extension of their wings, used to steer plankton and small fish into their mouth. Mantas have distinctive body blotches that naturalists use for identification because they are as unique as fingerprints. I’ve dived alongside, observed, and photographed dozens upon dozens of these magnificent and gentle animals at the Flower Garden Banks’ reefs. Recent research suggests that the Flower Garden Banks may be a nursery for mantas. Besides the manta rays (Manta birostris), which are seen year-round, two different mobulid rays, Mobula hypostoma and Mobula tarapacana, frequent the Flower Garden Banks in the spring and summer months. Mobulas, also known as devil rays, are smaller relatives of the mantas. And there’s more in the “big guy” department. Between the months of July and October, sport divers typically report at least a half-dozen encounters with whale sharks (Rhincodon typus) at the Gardens. During some three-month seasons, more than a dozen of these massive filter feeders have been sighted. These gentle giants often cruise near the surface in plankton-rich water, and sometimes they hang out in a tail-down position as if they’re waiting for something tasty to swim overhead. They feed on phytoplankton, shrimp, fish larvae, and other plankton by circulating huge volumes of water across their gill rakers. Whale sharks are easy to identify because of their massive bodies, up to fifty-five feet long, with their distinctive checkerboard pattern of pale yellow spots and stripes. It’s impossible to predict their whereabouts at or near the Flower Garden Banks National Marine Sanctuary. Nevertheless, hundreds of divers at the Flower Garden Banks can attest that they are definitely out there. Every winter without fail, schooling hammerhead sharks and eagle rays gather at the Flower Garden Banks’ reefs. The scalloped

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Remoras often hitch a free ride on manta rays and take advantage of any leftover scraps of food.

A silhouetted manta ray glides slowly above the reef while excited snorkelers vie for a closer look.

hammerhead sharks, Sphyrna lewini, are the most fascinating of these parading pelagic, or open-water, species. From December to early April, hammerheads congregate in packs of a dozen to fifty or more. Like most sharks, scalloped hammerheads are not aggressive or dangerous and are actually skittish around divers. Scuba regulator exhaust bubbles seem to keep them at a distance. If you wait long enough, you’ll see these magnificent animals swim by ten to thirty feet below the surface. Divers sometimes encounter schools of spotted eagle rays, Aetobatus narinari, during the winter. Their unusually long tails and white-ringed patterns make them easy to identify, even at great distances. Unlike the leisurely swimming mantas, eagle rays fly through the reef and seldom stop or even slow down. And unlike east and west flower garden banks

A nurse shark takes a swimming break on top of a coral head at the West Flower Garden Bank’s reef.

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Manta rays have distinct, unique body blotches that naturalists use for identification.

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other rays, the spotted eagle rays at times join the formations of hammerheads. In the fall, winter, and spring, silky sharks (Carcharhinus falciformis) make their appearance at the Flower Garden Banks National Marine Sanctuary. These sleek, silvery smooth-skinned sharks regularly school at the gas production platform a mile southeast of the East Flower Garden Bank reef. From just below the surface to depths of about thirty feet or more, large groups of silkies rhythmically circle and pass through the massive metal structure while thrilled divers scramble to get a closer look. east and west flower garden banks

During the winter months, spotted eagle rays school at the Flower Garden Banks.

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Schools of scalloped hammerhead sharks parade through the offshore reefs during the winter months when the inshore water temperatures plunge.

It’s always a thrill to witness the grace and beauty of a manta ray. Mature manta rays have wingspans that can reach up to fifteen feet across.

A Frogfish Tale

A longlure frogfish rests on a sponge at the East Flower Garden Bank’s reef. Frogfish use their built-in fishing rods to lure and capture prey.

In 2002 a diver from Austin was credited with spotting the firstever longlure frogfish at the Flower Garden Banks National Marine Sanctuary. Will Mitchell was on his way back to the mooring line at the end of an afternoon dive when he spotted this unusual fourinch-long fish at the East Flower Garden Bank reef. It was only his second trip ever to the Flower Gardens, and it was the first time he had seen a frogfish anywhere. Since the Flower Garden mooring buoys were installed in 1990, thousands of divers have visited these northernmost reefs in the continental United States and have never spotted such a prize. According to Mitchell, “What caught my eye was the outline of the frogfish as it sat on a piece of sponge. His color blended in so perfectly, but his image looked out of place on the sponge.” The longlure frogfish (Antennarius multiocellatus) has a “fishing lure” just above its lip, and has a variety of color phases—pink, green, yellow, and white. They have an excellent ability to camouflage themselves by changing color to blend with the background.

The goldentail moray is one of at least four different species of moray eels found at the Flower Garden Banks National Marine Sanctuary.

A pattern of spines on a porcupinefish.

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A diver approaches a loggerhead turtle plodding along the bottom at the East Flower Garden Bank’s reef. Loggerheads have thick necks, reddish-brown shells, and when fully mature, weigh up to 350 pounds.

Brine Seep The Brine Seep is a natural wonder on the eastern flank of the East Flower Garden Bank, where highly concentrated dissolved salt from the underlying dome oozes out of the seabed. A teardrop-shaped depression approximately 150 feet long by 100 feet across serves as a collection basin known as Gollum Lake. The brine is devoid of oxygen, is somewhat toxic to fish, and is seven times saltier than ocean water. Coral and rock over fifteen feet high form banks around the lake’s perimeter, giving it the look of a giant sunken amphitheater. The lake bottom slopes to the south and a slow-moving stream of brine empties into a forty-foot-wide canyon that stretches for more than a hundred feet. As the brine meanders through the canyon and around three huge boulders, it dilutes to lower and lower concentrations until it matches the salinity of seawater at the end of the canyon. The bottom at that point is 275 feet, a depth that people can view only with either a submersible or a special trimix gas and technical diving skills. Named after the shriveled creature in J. R. R. Tolkien’s Hobbit, Gollum Lake is less than a foot deep and has a distinctly weird whitish mat of algae and bacteria covering its surface. Every diver knows about thermoclines (abrupt temperature changes). This dive has

The dorsal spines of a longjaw squirrelfish.

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a “chemocline.” The chemistry of the lake changes from a condition having normal oxygen content to one totally devoid of oxygen. According to Texas A&M University scientists, most of the organisms living around the briny lake are sustained by sulfides instead of oxygen. These sulfide-dependent organisms are called thiobios and include small crustaceans, molluscs, and worms. Fish normally stay away from the lake, but one scientific survey team observed schools of cottonwick (Haemulon melanurum) diving into the brine to feed. Algae, sponges, and wire corals thrive just outside the basin’s perimeter. The reefs at the East and West Flower Garden Banks are like no other coral reefs in U.S. or Caribbean waters. These undersea oases host a remarkable community of life and tout manta rays, winterseason schooling hammerheads, and occasional whale sharks. But the best thing that can be said about the Flower Garden Banks is that they still are as they once were. east and west flower garden banks

A school of Bermuda Chub soar over a giant coral head at the West Flower Garden Bank reef.

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A school of small fish form a wrap in front of a coral head at the East Flower Garden Bank reef.

Stetson Bank A Macrophotographer’s Bonanza

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n October 1996 the National Oceanographic and Atmospheric Administration received approval to add Stetson Bank to the Flower Garden Banks National Marine Sanctuary. Stetson Bank is a 540-acre siltstone and claystone outcropping that lies seventy-five miles southeast of Freeport, Texas, and thirty miles northwest of the West Flower Garden Bank. The reef cap of this wedge-shaped formation is only thirty-six acres, the size of about twenty-five football fields. The top of the reef is about eight hundred yards long and two hundred yards wide and runs southwest to northeast. Stetson’s reef crests at depths ranging from fifty-five to ninety feet, and its northern boundary drops steeply to the flat, featureless bottom 180 feet below. Named after the oceanographer Henry C. Stetson, this popular Gulf bank is basically a salt-dome protrusion below a relatively soft stone base that hosts a thriving myriad of marine life. Stetson Bank has scattered brain and star corals but does not have the foundation or coverage to qualify as being a true coral reef. The bank has only about nine species of coral and overall less than 5 percent coverage, compared to the more than twenty species and greater than 50 percent coverage at the two Flower Garden Banks. Fire coral (Millepora alcicornis) and ten-ray star coral (Madracis decactis) are the most prevalent corals at Stetson Bank. Other corals found there include starlet coral (Siderastrea radians), small finger coral (Madracis asperula), brain coral (Diploria strigosa), and lettuce coral (Agaricia agaricities). Stetson’s signature feature is a series of fire coral and sponge-cloaked pinnacles that accent the reef top just inside its northern wall. Some of these peaks are wide and stubby and others are like pillars towering more than fifteen feet high. All abound

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Stetson Bank is not a true reef-building coral reef, but the fire corals, sponges, and coral patches there are exceptionally vivid in color.

More than a dozen sponge-covered pinnacles are scattered along the north rim of Stetson Bank’s reef crest.

Diver Vivian Dunlop watches the lively juvenile fish that inhabit the Madracis coral formation at Stetson Bank.

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with multicolored sponges, fire corals, bristly fire worms, and spiny sea urchins. Inside and away from the wall, Stetson’s reef top has distinct rows of ridges and troughs that result from the upward thrust of the bedrock. The terraces and gullies appear like the rough landscape you’d see in New Mexico. But unlike the deserts of New Mexico, Stetson is loaded with marine life. French angelfish the size of serving plates and at least four species of butterflyfish flutter around the pinnacles while scorpionfish in pairs and threesomes camouflage themselves against the algaecovered rocks. Spotted moray eels emerge from crevices, gaping their mouths as they pump water across their gills. Neon gobies and shrimp set up cleaning stations near the pinnacles for rock hinds and blue tang while dense schools of creolefish, brown chromis, and chapter two

creole wrasse fill the water column overhead. More than 125 species of fish are found at Stetson Bank. Some of the common invertebrates at Stetson are sea urchins, arrow crabs, sea cucumbers, and spiny lobsters. The more unusual invertebrates include the stunning cowries and the jet-black sea hares that inundate Stetson every June. The sand flats and rubble areas farther away from the drop-offs host sand tilefish, mantis shrimp, and the tiny yet fascinating sailfin blennies. At depths of seventy-five to eighty feet, the colors at Stetson are muted in the ambient sunlight. But turn on a video light or fire a flash and the reef ignites with dazzling Kodachrome colors.

A diver follows a scrawled cowfish as it swims along a pinnacle at Stetson Bank.

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At Stetson Bank, a neon goby takes a rest between cleaning duties on the face of a coney.

Squirrelfish have big eyes and a wary look. They prefer to stay under ledges or in any dark shadow they can find on the reef.

Magical Madracis One of my favorite dives at Stetson is buoy number 3, the farthest east of the five moorings. Swim directly to the wall from the U-bolt and you’ll see a magnificent and thriving formation of Madracis decactis coral commonly known as ten-ray star coral. A few orangeand charcoal-colored sponges and small amounts of fire corals compete for space, but the Madracis dominates a dramatic section of the wall about twenty by thirty feet. The lower portion of the Madracis slopes down the reef’s wall. Loads of creolefish often hover above the corals, and along the sides you’ll see banded coral shrimp, clusters of juvenile hogfish, and numerous bright red flamefish. Longspine squirrelfish and blackbar soldierfish also like to hang stetson bank

Bright red flamefish have distinctive lines across their eyes and are often seen at Stetson Bank hiding under reef overhangs.

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A diver swims along Stetson Bank’s most impressive coral formation, the Madracis decactis near buoy number 3.

Spiny lobsters are abundant at Stetson Bank, and fortunately they are protected by the “no-take” restrictions in place at the National Marine Sanctuary.

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out under ledges. Late one morning a few summers ago I encountered a ten-pound spiny lobster strutting across the Madracis coral like a cocky predator on a daylight stroll. Lobsters normally spend their days hiding out in the shadows of ledges or inside holes and are usually active only at night. Later I figured this one must have outgrown its shell and was starting to molt. Sure enough, a week later I returned to the reef and found a huge empty lobster shell on top of the coral. I was very fortunate to encounter one, considering the fact that lobsters that large molt only once every two or three years.

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A diver examines the community of fish at Stetson’s Madracis coral formation.

Red hinds often rest on ledges at Stetson Bank.

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A school of creolefish engulf a pair of divers at Stetson Bank.

Frogfish at Stetson

A charcoal-colored longlure frogfish perches on a sponge setting its bait for an unsuspecting prey.

In 2004 divers spotted a slate-colored longlure frogfish, Antennarius multiocellatus, resting on a similarly hued sponge near buoy number 3. This was a first for Stetson Bank. These unusual-looking short, fat fish don’t need to move much to find food. They typically plant themselves on a sponge and work their built-in “fishing rod,” which is actually the first spine of their dorsal fin. Frogfish have the ability to toss out a lure attached to a long, white filament to attract unwary fish passing within range. The unfortunate victims that succumb to the wiggle of the lure are not necessarily small fish. Frogfish do have tiny eyes but their tilted mouths are huge and their appetites are voracious. They can consume a fish larger than itself whole in a split second. Unfortunately, the frogfish at Stetson has not shown up again since the first year it was sighted, but I’m sure it’s still out there with other ones. Frogfish are just very well camouflaged.

A Golden Morph The golden morph of the smooth trunkfish, Lactophyrs triqueter, is another prize sighting at Stetson Bank. You can’t miss this one. The contrast of the bright, shiny yellow fish against the dark gray seafloor will stop you in your tracks. The normal coloration of this species is a dark body with white spots. There is no mistaking the triangular body, the odd, puckered mouth, and the awkward style of swimming characteristic of the boxfish family. Unlike most fish, trunkfish flutter around inefficiently with their tiny pectoral fins on overload. There are very few places you can see the golden morph, and the Flower Garden Banks National Marine Sanctuary is one of them. stetson bank

The rare and radiant golden morph of the smooth trunkfish can be seen at Stetson Bank and the Flower Garden Banks.

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A loggerhead turtle emerges from its hideout under a ledge at Stetson Bank’s northern drop-off.

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Sea Turtles Three different species of sea turtles make appearances at or near Stetson Bank. The most likely encounter is the loggerhead turtle, Caretta caretta, easily identified by its unusually large head, thick neck, and a reddish-brown shell. Loggerheads feed on jellyfish, crustaceans, sponges, and urchins. The hawksbill turtle, Eretmochelys imbricata, is a much less frequent visitor to the sanctuary, although a couple of them currently reside at Stetson Bank. Hawksbills are spongivores, so it makes sense for them to be found at Stetson Bank rather than at the East and West Flower Garden Banks where coral dominates the cover. Hawksbills have a slender, elongated head that tapers to a distinctive hooked jaw. Other distinguishing features are the two claws on their flippers. They feed on algae, tunicates, sponges, and corals. Hawksbills have beautiful patterns of streaking lines on their shells. Giant leatherback turtles, Dermochelys coriacea, are spotted from time to time on the surface near Stetson Bank. Their sheer size and leathery-looking shells are giveaways for easy identification. At Stetson Bank, divers frequently encounter sea turtles at any of the five mooring areas on the reef top and along the northern wall.

Loggerhead turtles are often seen at Stetson Bank free-swimming or hanging out beneath ledges along the drop-off.

Morays New divers are always especially thrilled to see their first moray eel, and Stetson Bank is a sure bet for sighting lots of them. At least four different species inhabit the reef: the goldentail moray (Gymnothorax miliaris), the spotted moray (Gymnothorax moringa), the viper moray (Echelycore nigricans), and the purplemouth moray (Gymnothorax vicinus). The spotted morays are by far the most common. Moray eels open and close their mouths in a continuous manner to drive water through their gills. This often causes new divers much consternation because they think the eel is getting ready to bite. Eels don’t typically bite, but you should never shove your hand in a dark hole or corner a moray eel. They have razor sharp teeth that look almost like fangs. stetson bank

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A purplemouth moray eel emerges from its hideout at Stetson Bank.

Sharks and Rays From buoy number 1, the most western buoy at Stetson Bank, it doesn’t take too long to swim to the far southwest end of the reef cap. There, a constant current sweeps across the bank’s wedge, a spot where a large population of sharks and rays always seems to congregate. You’re likely to see southern stingrays, a manta or spotted eagle ray, sandbar sharks, roughtail rays, or schools of blacktip sharks. Sharks and rays also like to cruise along the outside of the northern drop-off. And there’s an area east of buoy number 3 where divers sometimes spot nurse sharks.

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I’ve seen whale sharks at numerous locations around the world, but my first encounter with the largest fish on earth, at Stetson Bank in September 1992, is forever etched in my mind. I was getting ready for a Sunday morning dive when I heard a snorkeler yell, “Whale shark!” I scrambled to get in the water and somehow managed to bring along a camera loaded with film. It was a baby whale shark, only twelve feet long, and it swam slowly in wide circles around the dive boat, not once or twice, but so many times I lost count. In minutes I was out of film and swam back to the boat to reload. After changing film I was elated to see the baby whale shark was still circling the dive boat, much to the delight of the thirty divers and snorkelers.

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Whale sharks, the largest fish on earth, make occasional visits to Stetson Bank. These gentle giants feed primarily on plankton.

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The nonaggressive and easily approachable spotted scorpionfish commonly seen at Stetson Bank has a dorsal fin spine that is sharp and venomous.

Spotted Scorpionfish Spotted scorpionfish, Scorpaena plumieri, are mottled with reds and browns, have large heads, stocky bodies, and venomous dorsal spines. But divers usually look right at them and see only a background of earth tones. That’s because they sit motionless on the bottom and are masters of camouflage, easily blending into the rocky outcroppings. Look for the eyes; they are the giveaways. Once you spot them you’ll notice the plumage over their eyes called cirri. They also have several skin flaps on their heads. The fish’s venomous spine is for defense, but the camouflage works well for offense. They can easily ambush unsuspecting prey and gulp them down with their huge mouths. The poison from a spotted scorpionfish is painful but certainly not lethal.

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The spotted scorpionfish effectively camouflages itself against the earthtoned reef backdrop at Stetson Bank.

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Sailfin Blennies Sailfin blennies, Emblemaria pandionis, hide out on the bottom in holes and are commonly found in rubble areas and sand patches near buoy number 1. The male sailfin blenny has a black body and a matching colored sail-like dorsal fin. A mere one and a half to three inches long, you’ll be amused to see their tiny bulldog-­looking mugs. Male sailfin blennies flout their prominent sail fins when emerging from their holes. Approach slowly and you’ll witness a beautiful and entertaining exhibit as they rapidly flap their large dorsal fins in repetition. So what’s all the action about? The fin flicking is thought to attract females and to establish their turf.

Hawkfish Red-spotted hawkfish, Amblycirrhitus pinos, use their relatively large pectoral fins to perch on rocks and outcroppings, but they are way too skittish to sit in any one place for very long. Only two to four inches in length, red-spotted hawkfish have striking patterns of brown vertical bands and distinctive red spots on a palecolored body. As they flit around the reef they always keep you in their sights with one of their bright green eyes outlined in red. They seem to follow you around the reef but don’t like you to get too close. It’s not unusual to hear veteran Gulf of Mexico divers brag about Stetson Bank as their favorite dive site. The dense schools of fish overhead, the nonstop fish action on the reef, the fascinating invertebrates, and frequent turtle encounters all add up to exciting diving experiences. But the biggest draw is Stetson’s “surprise factor.” At Stetson Bank, there’s no telling what exciting pelagic fish you may encounter swimming overhead or along the northern wall. It could be a magnificent manta or eagle ray, a twelve-foot sandbar shark with a school of trailing fish, or even a thirty-foot whale shark. You just never know what to expect at Stetson Bank. stetson bank

The sailfin blenny emerges from its lair and extends its oversized dorsal fin in a fascinating display, flicking it up and down like a sail.

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The odd-shaped jackknife fish is found under ledges and is easy to identify because of its elongated dorsal fin and black and white bars on its head.

The graysby is a colorful and very approachable member of the grouper family.

Unafraid of divers, the petite and odd-shaped sharpnose puffer swims awkwardly and often hovers in a semicurled position.

The scrawled cowfish is a member of the odd-looking boxfish family and is easily identified by the distinctive blue patterns over its yellow body.

A mother bar-eyed hermit crab and her baby peek from their shells for a mother-and-baby portrait at Stetson Bank.

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Geyer Bank: A Tiny Splendor of Life

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eyer Bank is a very small but truly spectacular deeper reef in the northwestern Gulf of Mexico. It hosts an impressive community of tropical fish and sessile reef inhabitants. Because Geyer’s depth is so near the recreational dive limit of 130 feet, it is not on the standard travel plan for the Texas live-aboard dive boats. As a result, few divers in the region have even heard of Geyer Bank, let alone have dived there. Geyer today is about as virgin as a reef can be in the continental United States. At 120 nautical miles southeast of Galveston, Texas, or about thirty miles due east of the East Flower Garden Banks, Geyer Bank is a bulb-shaped formation. It sits very near the outer edge of the continental shelf, and its sides rise steeply from depths of more than 600 feet to a plateau at about 250 feet. Numerous tiny peaks rise from the platform of the bank, and at least two of them project up to within 130 feet from the surface. In 2001 I led the first exploratory trip of sport divers to Geyer Bank aboard a ninety-foot dive boat with the intent to find and photograph one or more of its tiny peaks. Working with a set of geographical-positioning-system coordinates from a scientific survey and another slightly different set of numbers obtained from a fishing boat captain, we probed the bottom. Geyer Bank covers an area of twenty square miles and thus is easy to find, but the peaks we searched for were tiny, no larger than half the size of a football field. All sixteen divers on board knew it was a gamble to find a peak shallow enough to dive to, but in less than two hours we hit pay dirt. The bottom finder hit a small section of reef that crested

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The Geyer Bank outcroppings are more like Stetson Bank and Sonnier Bank than the Flower Garden Banks’ reefs. Geyer Bank has a thriving reef community; its reef cover is dominated by Millepora (fire) coral, touch-me-not Neofibulara sponges, and leafy algae.

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Sponges, fire corals, and algae cover the tiny reef top at Geyer Bank.

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at 105 feet from the surface. We set the anchor off the reef top in much deeper water, hoping to avoid any damage to the live reef. The reef cap is basically a rock and claystone foundation dominated by huge, sprawling touch-me-not sponges, large formations of Millepora fire corals, and dense expansive fields of leafy, bright green algae. The reef has a unique look but appears more like Stetson and Sonnier Banks than the Flower Garden Banks. Geyer Bank features several heads of coral scattered across the crest of the reef. Orange cup corals (Tubastraea coccinea), a Pacific Ocean species, have chapter three

gained a foothold on Geyer Bank. It’s a stunning coral to behold, but marine scientists consider it an invasive species and possible threat to the balance of the ecosystem. The fish in the water column and on the reef are profuse beyond anything I’ve ever seen in the Gulf of Mexico. Butterflyfish, brown chromis, triggerfish, Spanish hogfish, squirrelfish, and queen angelfish dominate the population. Rock beauties, ocean triggerfish, juvenile clown wrasses, bicolor coneys, and black durgeons flitted and fluttered over the reef, seemingly indifferent to our presence. The reef butterflyfish, Chaetodon sedentarius, hovered over the reefs in masses greater than I’ve encountered anywhere in the world, including the South Pacific. There were hundreds upon hundreds virtually swarming the reef. The multitudes seemed to overwhelm the tiny reef in every direction. At Geyer, the butterflyfish truly earn their name, as they mimic a delightful flutter of white and yellow wings descending on a lush meadow. Reef butterflyfish are a deeper dwelling species of the chaetodontids (butterflyfish family). They have compressed bodies and short, pointed snouts. Their bodies are silver or white, with yellow and black dorsal fins and a yellow tail. The two vertical black bars running down the frontal and rear sections of their bodies are distinctive. It’s thought that these dark bands confuse their predators. Whatever it is that confuses their predators, it definitely works well at Geyer Bank. The threadnose bass, Anthias tenuis, is another impressive fish found at Geyer Bank. These bright orange, planktoneating streamer bass normally live hundreds of feet deep, but for some reason are attracted to Geyer’s reef top. Schooling hammerhead sharks, Sphyrna lewini, are a winterseason sensation at the Flower Garden Banks. For reasons not fully understood, every year from January through March, these normally nonthreatening animals congregate at the East and West Flower Garden Banks, but they are almost never seen during the summer months. Little is known of the patterns of movement of the hammerhead sharks, but we discovered they don’t all move away from area reefs in the summer. In July on two different dives at Geyer Bank, we saw schools of up to sixteen scalloped hammerheads blasting their way through the deep blue backdrop. Their light brown bodies, white undersides, and distinctive hammers were a beautiful geyer bank

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Hundreds of reef butterfly fish congregate at a small rubble clearing at Geyer Bank.

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Photographer Joe Nicklo moves in close to photograph a lively school of reef butterflyfish.

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sight to behold. Scalloped hammerheads are found in both inshore coastal areas as well as offshore, deeper environments. Some populations remain stationary while others migrate. And some hammerheads may be attracted to seamounts or banks. For the animals that do migrate, recent studies suggest hammerhead sharks make use of the earth’s magnetic fields to navigate. The “hammer” of the scalloped hammerhead has a central indentation and a distinctive scalloped front edge. Our brief bottom times on the reef top were more than compensated by the thrill of making “first-ever dives” at Geyer Bank. One of the photographers on the first trip there documented a gold-faced toby, Canthigasta jamestyleri, a deep-dwelling puffer species only recently identified. This particular puffer is similar to but more colorchapter three

ful than a sharpnose puffer. Another diver surfaced with a dive slate listing thirty-six different species of fish, including prized sightings of sargassum triggerfish, marbled grouper, spotted eagle ray, and red-spotted hawkfish. Because of its depth, Geyer Bank is a site for experienced divers only. In order to maintain a no-decompression dive profile, divers must keep their time on the reef very brief, in the order of ten to fifteen minutes. Otherwise the effect of increased nitrogen intake would require a diver to undergo a decompression procedure longer than the typical five-minute safety stop at fifteen feet. Since 2001 I’ve led annual return trips to Geyer and have not been disappointed with the scenery or my encounters with reef inhabitants. The reef butterflyfish are still there, and the reef remains lush and pristine.

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A scrawled cowfish glides across a sponge-covered head at Geyer Bank.

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Sonnier Bank: A Louisiana Treasure

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nown as Three Hickey Rocks by some and Candy Mountain by others, Sonnier Bank was renamed in honor of the late Farley Sonnier, a Louisiana attorney and marine naturalist who devoted much of his life to this unique marine oasis of life. Unlike the Flower Garden Banks that are shared by Texas and Louisiana, Sonnier Bank is truly a Louisiana reef. It’s actually a cluster of eight tiny peaks that form an arclike pattern on the nautical chart. The shallowest and most prominent of the peaks are the two that rise from the surrounding 180-foot depths to within sixty feet and eighty feet from the surface. Sonnier’s siltstone and claystone composite substrate is strikingly similar to that of Stetson Bank, which is part of the Flower Garden Banks National Marine Sanctuary. Like Stetson, sponges and Millepora fire corals, not reefbuilding stony corals, dominate the reef cover at Sonnier Bank. The reef terrain is also similar to Stetson Bank, having an uplifted caprock that forms sculpted outcrops and lines of deep ridges. Unlike the extensive hard coral covers at the East and West Flower Garden Banks, Sonnier Bank supports at least eight species of coral, which are conspicuously scattered around the reef top. My last trip to Sonnier Bank was an unforgettable adventure. At two o’clock in the morning on one July Saturday, not quite halfway through the boat run to Sonnier, I was awakened by what sounded like an explosion. I leaped out of my bunk and hit the light switch, but all I could see was smoke. After three failed attempts in as many years to dive Sonnier Bank, I wasn’t about to let over-twenty-knot winds and six-foot seas stop us from getting there. Now, because

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A spotted moray eel eases its way through a crevice in the fire-coral-covered reef at Sonnier Bank.

A dainty lookdown appears as a neartranslucent disc swimming through the reef at Sonnier Bank. Lookdowns are much more common on the rigs than on the natural reefs.

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of my persistence, twelve of my dive buddies and I thought we were going down in flames sixty miles off the coast of Texas. Fortunately, there was smoke but no fire. The impact of a big wave caused the oven to slide away from the bulkhead, shorting out the power cable and searing the electrical insulation, creating a temporary cloud of smoke. The “explosion” was the refrigerator and freezer dislodging its entire contents onto the galley floor after another rogue wave jolted the latches off the doors. The captain backed down on the throttle and we eased ahead, reaching our destination a mere four hours behind schedule. I was both refreshed and relieved when I finally entered the water and began my descent for that first dive at Sonnier Bank. A huge school of horse-eye jacks approached me nearly head on as I finned toward Sonnier’s single U-bolt mooring installed in July 1996 by volunteers for the Gulf Reef Environmental Action Team. Seconds after this powerful mass of silver rushed by me, a shiny school of dainty lookdowns fluttered through the reef. Lookdowns are common on the rigs but not so common on natural reefs. As I focused toward the bottom I could see thick swarms of brown chromis and reddish-purple creolefish hovering over the outcrops while an enerchapter four

gized school of rainbow runners soared by. Multicolored parrotfish and clusters of angelfish perusing the reef top soon came into view. Everywhere I turned, I saw loads of fish, including a multitude of juveniles. Like the familiar sponge-cloaked spires at Stetson Bank, Sonnier’s eighty-foot peak has a set of pinnacles covered almost entirely with orange elephant-ear sponges and chartreuse fire coral. Smaller patches of yellow and pink encrusting sponges are smeared across the reef like melted creamsicles. Loggerhead sponges, irritating touch-me-not sponges, vase sponges, and sturdy black-ball sponges make Sonnier a tasty snack bar for an exceptionally large community of angelfish. Brown spiny brittle stars and iridescent orange fire worms crawl across the reef top while bright red sea sonnier bank

A creolefish takes refuge beneath a massive mat of coralline algae at Sonnier Bank.

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The roughtail ray, named for its thick, thorny tail, is one of the largest rays in the Gulf of Mexico. Tip to tip wingspans exceed six feet.

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cucumbers make tracks at a snail’s pace across the sand channels. The abundance of cowries and a thriving population of spiny lobsters are obvious indicators that Sonnier Bank is seldom visited by humans. Manta rays and southern stingrays are common animals in the northwestern Gulf of Mexico, but as I approached a pair of giant, dark discs lying in the sand, I could tell these rays were much too large to be southern stingrays. Each ray’s body was at least five feet across and their tails equally long. The nearest one allowed me to approach within inches before I noticed an eye blink. I learned later that the numerous spines scattered across their backs and along the base of their tales distinguish them as roughtail rays (Dasyatis centroura), one of the largest types of stingrays in the Atlantic. The angelfish at Sonnier Bank seem bigger and more brightly colored than any I’ve seen elsewhere except perhaps for Stetson Bank. And I’ve never seen so many in such a small area. Sonnier’s eighty-foot peak is less than three hundred feet across, yet on a

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The Townsend’s angelfish, once thought to be a separate species, is actually a hybrid produced by a blue and queen angelfish.

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Townsend’s angelfish circle a massive barrel sponge in the midst of a field of leafy algae at Sonnier Bank.

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single dive I encountered queens, blues, French, and rock beauties. At one cluster of barrel sponges, more than a dozen angelfish circled and nibbled, not the least bit bothered by the sharp, irritating tissues of the sponges. Sonnier Bank is also a habitat for a somewhat uncommon angelfish. The Townsend’s angelfish is a naturally occurring cross between a blue and a queen angelfish. They come in several variations. Some have a crown on their heads and some the body and tail features of a blue angelfish, while others have the body of a queen minus the distinctive crown. At one time the Townsend’s angelfish was thought to be a separate species, but scientists now agree it’s a hybrid and not a true species. Access to Sonnier Bank remains limited to private boats and custom charters. That is good news for the reef and its inhabitants and very good news for the few divers fortunate enough to visit this pristine and vibrant community of sea life off the Louisiana coast.

chapter four

Artificial Reefs

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eefs provide an important habitat for myriad marine life, from algae and molluscs to tropical fish and large predators. Reef-forming organisms such as corals need hard surfaces on which to establish a foothold for growth and development. Aside from the relatively few, small, and far-between natural reefs, the bottom of the Gulf of Mexico off the Texas coast is predominantly flat, featureless, and soft. There are few areas that allow reef-forming coral larvae to settle and anchor. Consequently, oil and gas production platforms and other artificial reefs play an important role in providing habitats for marine life in the Gulf of Mexico. Texas’s revitalized Ships-to-Reef Program and recently launched Public Reefing Program compliment the centerpiece Rigs-to-Reef Program.

Operating Gas and Oil Platforms Oil and gas production platforms seem to randomly dot the northwestern Gulf of Mexico like thousands of iron islands. Some are within sight of the shore, and others lie more than a hundred miles off the coast. Their main purpose is producing energy, yet below the waterline these structures provide important habitat for marine life. Thriving communities of fish and invertebrate sea life homestead beneath the many energy platforms, both large and small. A single platform in 150 feet of water can provide the equivalent surface area of more than an acre of natural reef area. The High Island 389 gas platform, a popular rig dive near the East Flower Garden Bank’s reef, is completely covered with years of

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Below the waterline, operating production platforms are like iron reefs for a thriving community of marine life.

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marine growth. Iridescent blue tube sponges and bright red encrusting sponges compliment the dense cover of white, fuzzy hydroids and octocorals. Spanish hogfish, puffers, angelfish, and dozens of other tropical fish find food and refuge as they flit and flutter around this human-engineered structure that is bathed and replenished by Gulf Stream eddies. The High Island 389 platform, one of approximately four thousand platforms in the northern Gulf of Mexico, is a hands-down favorite for scuba divers visiting the Flower Garden Banks National Marine Sanctuary. The visibility normally exceeds one hundred feet, and the wildlife encounters range from the miniscule resident blennies to the eight-foot silky sharks that visit regularly. Whale sharks, the largest fish in the ocean, are spotted here from time to time. Conditions need to be just right to dive the platform—minimal current and calm seas, with just enough wind to hold the boat safely off the structure. The silky sharks aren’t there all the time, but whether they’re there or not, High Island 389 is one impressive platform dive. chapter five

A school of crevalle jack swim through the High Island 389 platform near the East Flower Garden Bank.

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Weekend divers on small private boats visit the dozens of platforms closer to shore. Sport-dive operators also visit the platforms nearshore on their way back from trips to the Stetson Bank and Flower Garden Banks. Boats usually tie off directly to the platforms and run a travel line to a crossbeam at a depth of twenty-five to thirty feet. This allows safe, easy access to the platform’s interior. On descent, the water column darkens inside the structure, producing a mood effect. Some divers describe it like being in a cathedral. For the spearfishers, it’s more like heaven as they pursue snapper, grouper, and other tasty fish. Schools of Atlantic spadefish and glittery lookdowns swirl around the steel framework while sergeant majors, triggerfish, and cocoa damselfish browse closer to chapter five

A school of silky sharks cruise for prey just outside High Island 389 gas platfofrm.

A Townsend’s angelfish swims through a school of creolefish at the High Island 389 platform.

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The small and skittish tessellated blenny is easy to spot with the flamboyant orange spots on its body and head.

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Seaweed blennies are usually seen resting on their pectoral and ventral fins. This seaweed blenny is in its yellow phase.

A seaweed blenny emerges from its hideout in an empty barnacle shell and perches on a red encrusting sponge.

This seaweed blenny has distinctive green eyes and light blue lines radiating from its eyes.

Diver Gina Short is amused by the antics of a seaweed blenny hiding out in an empty barnacle shell.

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the ­jackets and beams. The shallow cross members are where the macrophotographers carefully position themselves to capture shots of the flamboyant tessellated blennies. Hundreds of these tiny fish, with their exaggerated heads, orange-spotted faces, huge eyes, and antlers to boot, populate the empty barnacles that riddle the metal beams and struts. Inhabitants you’d least expect to see include spiny lobsters, octopus, and shrimp, which often hide out in the corners of the framework. The vertical stratification of the biological community is another fascinating aspect of these human-made reefs. The mix of attached organisms changes with depth, as does the community of fishes. Green algae, acorn barnacles, and oysters dominate the cover from the surface to about thirty feet. Sergeant majors, blennies, and sharpnose puffers favor the shallow depths along with schools of Bermuda chub and barracudas. Below thirty feet the amount of fish chapter five

life increases significantly. Damselfish, brown and blue chromis, and creolefish rule much of the water space but rarely move far from the surface of the structure. Rock hinds and soap fish stay even closer to the legs and bracing, maintaining contact with their pectoral fins. The surfaces are covered mostly with hydroids, sponges, tunicates, cup corals, and many forms of bryozoans that are often mistaken for coral or sponges. Arrow crabs use their stilted legs to maneuver through the thick growth, while other crabs and spiny lobsters find refuge in the crannies where the beams and braces connect to the legs. Below fifty feet, the algae and barnacles are replaced with

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The arrow crab, with its teardrop body, pointed head, and long spindly legs, looks almost like a spider.

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Colorful sea anemones thrive on many of the gas and oil platforms.

The goliath grouper is the largest of the groupers; adults can weigh more five hundred pounds. They feed on fish and crustaceans.

A balloonfish, Diodon holocanthus, emerges from its hideout in an offshore platform. It has long spines that are usually lowered and raised only when alarmed. Notice the green iridescent specks in the fish’s pupils.

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hydroids, sponges, and tube worms. You need to descend to sixty feet or below to spot redband parrotfish, bicolor damsels, seaweed blennies, and groupers. Some fishes, like the gray triggerfish and Spanish hogfish, seem to know no boundaries, moving from shallow to deep portions of the platform at will. They power themselves from a hundred feet or deeper all the way to the surface and then back down with total disregard to stratification.

Decommissioned Platforms In 1989 Texas enacted the Artificial Reef Act, providing incentives to oil and gas companies willing to donate obsolete platform structures to the program. The corporations also donate half of the

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Backlighting of the rig structure and a diver creates a silhouetted etching in blue that gives a feeling of awe and reverence.

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Diver Ted Wimprine searches for critters hiding out in the lush cover of life typically found on the offshore bluewater rigs.

savings realized from not having to tow the decommissioned platforms to shore. The remainder of the savings is their incentive. This arrangement allows the Texas Artificial Reef Program to fund its operations without tax dollars. Corporations have already donated millions to the fund. The Texas Parks and Wildlife Department is responsible for monitoring all rigs-to-reefs activities and currently manages ninety recycled reef platforms at forty-five sites that range from less than ten miles to just over a hundred miles offshore. Nearly all the artificial reefs are at depths suitable for sport diving. Some of these platforms were toppled in place, many were towed from other locations, and the rest were “partially removed.” A partial removal usually entails severing the upper section of the jacket from the base at a depth of eighty-five feet. The upper section is then placed on the seafloor next to the base. Instead of using explosive charges for the separation, the cuts are made mechanically. This approach keeps most of the platform remains intact and minimizes disruption to the existing biological community. The top portion of the structure, which is set on the bottom, has to be reestablished biologically since many of the shallow-water organisms are not adapted to live at the lower depths. According to Doug Peter, artificial-reef biologist for Texas Parks and Wildlife, “Partial removals were started in Texas. It’s a good deepwater application. The intent is to keep the base secured to the bottom and to allow the platform to stay as high as possible in the water column. There’s a zone of very good biological production at 85 to 100 feet.” How are locations chosen for these reefs? According to Dale Shively, Parks and Wildlife artificial-reef coordinator, “Most are set at predetermined sites approved by the U.S. Army Corps of Engineers. The site approval process also involves the Minerals Management Service, the Coast Guard, and a citizen’s advisory committee.” Most locations require a mandated minimum clearance of eighty-five feet for navigational reasons. This allows buoy removal after the site is charted and also means most sites are at least twenty-five miles or farther offshore. Also, acceptable sites need relatively stable bottoms, and the structures cannot be placed on top of any natural reefs or outcroppings.

The sun sets beside a production platform in the northwestern Gulf of Mexico.

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Although obsolete platforms are the most common material used for artificial reefs, others are used as well. Shively explains that the 1984 National Artificial Reef Act describes the types of materials suitable for human-made reefs. The objects used must be clean, stable, durable, and suitable in size and configuration for providing prime fish habitat. Cars, tires, and materials that scatter in storms are not permitted in the Texas program. The platforms legs or “jackets” work extremely well since they are simply the steel support structures for the platform’s above-water decks. The platform decks above the waterline contain the gas and oil processing equipment and are not typically turned into reefs due to the cost of making them environmentally acceptable. Do the artificial reefs really add population to the environment or simply concentrate existing populations? Doug Peter contends they do both. He explains that some of the artificial reefs closer to shore that are more heavily fished seem to attract primarily fish, but the structures farther offshore are highly productive, providing significant vertical habitat in water depths of one hundred feet or more.

Freeport Liberty Ship Reef. Courtesy of Doug Weaver, Flower Garden Banks National Marine Sanctuary.

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Divers explore the wreck of the V.A. Fogg, the centerpiece of the Freeport Liberty Ship Reef Complex.

Ships-to-Reefs The Texas Ships-to-Reef Program began in the mid-1970s with the sinking of twelve “Liberty ships” at six different sites along the Texas coast. Liberty ships were used to carry troops and supplies to Allied fronts during World War II. The wreck of the V.A. Fogg tanker was incorporated into the program when two Liberty ships were sunk in its vicinity. There are plans to add the 473-foot Texas Clipper to the program in 2007. This World War II transport and attack ship was more recently utilized as a maritime training vessel for Texas A&M University in Galveston from 1965 to 1993. Her selected reef site is seventeen miles east off South Padre Island in 135 feet of water. The Freeport Liberty Ship Reef Complex is a popular artificial-reef dive site located thirty-six miles southeast of Freeport, Texas. This 160-acre marine park includes the wreck of the V.A. Fogg, two intentionally sunk Liberty ships, six decommissioned jackets, a welded pipe structure, and a unique fly-ash pyramid. All structures rest in one hundred feet of water. The park’s focal point is the V.A. Fogg, a nearly empty tanker that, without any warning, exploded, caught fire, and sank in February 1972. Schools of crimson bigeyes and silvery artificial reefs

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Chromis, wrasse, and damselfish frolic around tube sponges on a beam at the High Island 389 platform.

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grunts now find refuge in this twisted metal hulk. A few years later, two 441-foot long Liberty ships were placed nearby as part of a wider effort to create new habitats for marine organisms. The coal-fly-ash reef consists of more than three hundred blocks of recycled boiler ash produced from Houston Power and Light Company’s fossil fuel power plants. It took little time for a living mat of algae, barnacles, and encrusting sponges to cover the four-foot cubes. Conoco and Galveston County donated a welded pipe structure and cable slings, which look like a huge underwater jungle gym where snapper, spadefish and amberjack come to play. The six recycled oil and gas platforms, known as Star Reef, are configured on the bottom in the shape of a star. The recently launched Texas Public Reefing Program allows the general public to participate in building reefs closer to shore at shallower depths than the other reefs managed by the Texas Parks and Wildlife Department’s Artificial Reef Program. The process requires an applicant to submit to the Texas Parks and Wildlife Department a list of proposed reefing materials. Once approved, the applicant can deploy the artificial reef at a preapproved site. The applicant must incur all costs required to complete the reef and comply with all the established rules and guidelines. Early indications suggest that the Texas Artificial Reef Program is helping counteract the declining red snapper population due to overfishing. According to Texas Parks and Wildlife’s Shively, “The red snapper are definitely spawning around the human-made structures, and populations around the platforms appear to be on the rise.” Biologist Peter has personally monitored artificial reefs since 1994 and is convinced that the Texas artificial reefs provide an excellent habitat that’s been proven by the growing aggregates of fish populations found on them. Today the Texas Artificial Reef Program manages fifty-eight reef sites. Material deployed at the sites include 712 fabricated materials, such as concrete reef balls, concrete utility poles, fly-ash blocks, more than 225 quarry rocks, ninety gas and oil rig structures, and twenty ships and barges.

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Index

Page numbers in italics refer to photographs, and those in boldface refer to maps. Aetobatus narinari, 43, 45 Agaricia agaricities, 57 algae, 4, 18, 52–53, 88–90, 90 Amblycirrhitus pinos, 83 anchors, boat, damage to reefs from, 11 anemones, sea, 116–17 angelfish, 18, 103–104, 104, 109 Antenarius multiocellatus, 48, 48, 72 Anthias tenuis, 91 arrow crabs, 115 Artificial Reef Act (1989), 119 Artificial Reef Program, 122, 128 artificial reefs: decommissioned oil and gas platforms, 119–24; introduction, 5–6, 105; operating oil and gas platforms, 105–19, 126–27; sunken ship reefs, 124, 125, 128 balloon fish, 118 barracudas, 14 barrel sponges, 28, 104

Bermuda chub, 53 Biota of the West Flower Garden Bank (Bright and Pequegnat), 1 black band disease, 5 bleaching of coral reefs, 4 blennies, 82, 83, 110–11, 112–14, 114 blue angelfish, 18, 103–104, 104 boulder star corals, 23, 26–27 brain corals, 9–10, 23, 57 Bright, Thomas, 1–2 Brine Seep, 52–53 butterflyfish, 91, 92–94 Candy Mountain (Sonnier Bank), 97–104 Canthigasta jamesstyleri, 94–95 Carcharhinus falciformis, 45 Caretta caretta, 50–51, 77 Chaetodon sedentarius, 91, 92– 94 “chemocline” and Brine Seep area, 52–53 coney fish, 64 coral species: at Flower Garden Banks, 9–10, 16–17, 18–28, 20–21; at Geyer Bank, 88–90, 90–91; health and protection

of, 2–3, 5, 23; mass spawning event, 29–33; as reef builders, 3–4; at Sonnier Bank, 97, 98–99; at Stetson Bank, 57, 58–59, 62, 65–69, 66–67 cottonwick fish, 53 cowfish, 63, 85, 95 crabs, 34–35, 85, 115 creolefish, 16–17, 22, 38, 70–71, 101 creole wrasses, 20, 24–25 crevalle jack fish, 107–8 crustaceans: crabs, 34–35, 85, 115; at Flower Garden Banks, 23; shrimp, 14–15; spiny lobsters, 68, 68 Dasyatis centroura, 102, 102 decommissioned oil and gas platforms, 119–24 Dermochelys coriacea, 77 devil rays, 40 Diodon holocanthus, 118 Diploria strigosa, 9–10, 23, 57 diseases, reef, 4–5 diving technology, 8 Dunlop, Vivian, 21, 62

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eagle rays, 40, 43, 45, 45 East Flower Garden Bank: and Brine Seep, 52–53; coral population, 12–13, 20–21, 23; fish population, 54–55; introduction, 9; map, 10 Echelycore nigricans, 77 eels, moray, 49, 77, 78, 98–99 Emblemaria pandionis, 82, 83 environmental issues: and artificial reef development, 128; oil and gas activity damage to reefs, 11; and placement of platforms-to-reefs, 122; and reef health, 2–3, 5; and reef protection, 7–8, 23 Eretmochelys imbricata, 77 fire coral, 57, 88–90, 90, 97, 98–99 fishing at artificial reefs, 6 fish species: at Flower Garden Banks, 10, 14, 16–20, 22–27, 36–39, 48–49, 52–55; at Geyer Bank, 91–95; at oil and gas platforms, 106–109, 114–15, 118–19, 126–27; red snapper preservation, 128; at ship reefs, 125; at Sonnier Bank, 100–104; at Stetson Bank, 62–65, 69–72, 80–85 flamefish, 65 Flower Garden Banks: author’s discovery of, 1–2; Brine Seep, 52–53; coral colonies, 9–10, 12–13, 18–28; crustaceans, 23, 34–35; development of, 11;

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ecological value of, 2; ecosystem of, 2–8; fish species, 10, 14, 16–20, 22–27, 36–39, 48–49, 52–55; frogfish, 48, 48; introduction, 9–10; map, 10; mass spawning, 29–33; rays, 40–47; sea turtles, 50– 51; sharks, 40–47; shrimp, 14–15 Flower Garden Banks National Marine Sanctuary, 7, 11 Freeport Liberty Ship Reef, 10, 124, 125, 128 frogfish, 48, 48, 72 geology of coral reef, 11, 23, 97 Geyer Bank, 10, 87–95 golden morph of smooth trunkfish, 72 goldentail moray eel, 49, 77 gold-faced toby, 94–95 goliath grouper, 118 Gollum Lake, 52 graysby fish, 84 great star coral, 23, 32, 33 Guillen, Isabelle, 28 Gulf of Mexico: conditions for reef development, 9, 11, 105; reef overview, 1–8 Gymnothorax miliaris, 49, 77 Gymnothorax moringa, 77 Gymnothorax vicinus, 77 Haemulon melanurum, 53 hammerhead sharks, 40, 43, 46, 91, 94 hawkfish, 83 index

hawksbill turtle, 77 hermit crabs, 85 High Island 389 gas platform, 10, 105–106, 107–109, 126–27 Hurricane Rita, 5 hurricanes, impact on reefs, 5 International Maritime Organization, 11 invertebrate species: anemones, 116–17; at Flower Garden Banks, 23; at oil and gas platforms, 106, 114, 115, 119; sea urchins, 4; starfish, 36–37; at Stetson Bank, 63. See also coral species; crustaceans; sponges jackknife fish, 84 jawfish, yellowhead, 19 juvenile fish, 62 leatherback turtles, giant, 77 lettuce coral, 57 lobsters, spiny, 68, 68 loggerhead turtles, 50–51, 77 longjaw squirrelfish, 52 longlure frogfish, 48, 48, 72 lookdown fish, 100, 100 Loop Currents, Gulf of Mexico, 9 Louisiana and Sonnier Bank, 97–104. See also Flower Garden Banks Madracis asperula, 57 Madracis decactis, 57, 65–69, 66–67

manta rays (Manta birostris): at Flower Garden Banks, 40–47, 41–42, 44, 47; at Sonnier Bank, 102, 102 Marine Protected Areas (MPAs), 7–8 mass spawning, 29–33 Millepora alcicornis, 57, 88–90, 90, 97, 98–99 Minerals Management Service, 3 Mitchell, Will, 48 Mobula hypostoma, 40 Mobula tarapacana, 40 mobulid rays, 40 mollusks, 23 Montastraea annularis, 23 Montastraea cavernosa, 23, 32, 33 Montastraea favedata, 23 Montastraea franksi, 23 moorings at Flower Garden Banks, 11 moray eels, 49, 77, 78, 98–99 MPAs (Marine Protected Areas), 7–8 mustard hill coral, 23 National Artificial Reef Act (1984), 124 National Oceanic and Atmospheric Administration (NOAA), 3 Neofibulara, 88–90 neon goby, 64 Nicklo, Joe, 94 nurse sharks, 43

oil and gas production platforms, 6–8, 11, 45, 105–24, 126–27 operating oil and gas platforms, 105–19, 123, 126–27 orange cup corals, 90–91 parrotfish, 4, 14, 26–27, 39 partial removals of oil and gas platforms, 122 Pequegnat, Linda, 1 Peter, Doug, 122, 124, 128 photosynthesis on reef, 4, 18 porcupine fish, 49 Porites astreoides, 23 princess parrotfish, 39 puffer fish, 84, 94–95 purplemouth moray eel, 77, 78 queen angelfish, 103–4, 104 rays: at Flower Garden Banks, 40–47, 41–42, 44, 45, 47; at Sonnier Bank, 102, 102; at Stetson Bank, 78–79 recreational impact on reefs, 11 redband parrotfish, 14 red hinds, 69 red night shrimp, 14–15 red-ridged clinging crab, 34–35 red snappers, 128 red-spotted hawkfish, 83 reef butterflyfish, 91, 92–94 remoras, 41 reproduction, coral reef, 29–33 Rhincodon typus, 40, 79, 79, 106 Rhynchocinetes rigens, 14–15

Rinn, Gary, 11 roughtail rays, 102 ruby brittle stars, 36–37 sailfin blennies, 82, 83 salt domes, 3, 11, 52–53 scalloped hammerhead sharks, 40, 43, 46, 91, 94 Scorpaena plumieri, 80, 80–81 scorpionfish, 80, 80–81 scrawled cowfish, 63, 85, 95 sea anemones, 116–17 sea turtles, 50–51, 74–76, 77 sea urchins, 4 seaweed blennies, 112–14 sessile organisms: algae, 4, 18, 52–53, 88–90, 90; settlement on artificial reefs, 6 sharks: at Flower Garden Banks, 40–47, 43, 46; at Geyer Bank, 91, 94; at oil and gas platforms, 106, 109; at Stetson Bank, 78–79 sharpnose puffer fish, 84 ships as reefs, 105, 124, 125, 128 Ships-to-Reefs Program, 105, 124, 125, 128 Shively, Dale, 122, 124 Short, Gina, 114 shrimp, 14–15 Siderastrea radians, 57 silky sharks, 45, 109 small finger coral, 57 smooth trunkfish, 72 Sonnier Bank, 10, 97–104 southern stingrays, 102, 102 spawning, coral, 29–33

Sphyrna lewini, 40, 43, 46, 91, 94 spiny lobsters, 68, 68 sponges: at Flower Garden Banks, 9, 22, 23, 28; at Geyer Bank, 88–90, 90; at Sonnier Bank, 23, 28, 97, 101, 104; at Stetson Bank, 57, 60–61, 77 spotted eagle rays, 43, 45, 45 spotted moray eel, 77, 98–99 spotted scorpionfish, 80, 80, 81 squirrelfish, 52, 64 star corals: at Flower Garden Banks, 9–10, 16–17, 23, 26–27, 32, 33; at Stetson Bank, 57, 65–69, 66–67 starfish (ruby brittle stars), 36–37 starlet coral, 57 Star Reef, 128 Stetson, Henry C., 57 Stetson Bank: coral species, 57–59, 62, 65–69; creolefish at, 70–71; fish species, 62–65,

132

69–72, 80–85; introduction, 57–64; map, 10; moray eels, 77, 78; rays, 78–79; sea turtles, 74–76, 77; sharks, 78–79 stingrays, southern, 102, 102 sunken ship reefs, 105, 124, 125, 128 ten-ray star coral, 57, 65–69, 66–67 tesselated blennies, 110–11, 114 Texas Artificial Reef Program, 122, 128 Texas Clipper, 125 Texas Parks and Wildlife Department, 122 Texas Public Reefing Program, 128 Texas reefs, introduction, 1–8. See also Flower Garden Banks; Geyer Bank; Stetson Bank threadnose bass, 91 Three Hickey Rocks (Sonnier Bank), 97–104

index

touch-me-not sponges, 88–90, 90 Townsend’s angelfish, 103–4, 104, 109 trunkfish, smooth, 72 Tubastraea coccinea, 90–91 tube sponges, 22 turtles, sea, 50–51, 74–76, 77 urchins, sea, 4 V.A. Fogg, 125 viper moray eel, 77 water temperatures and stress on coral, 4 West Flower Garden Bank, 9, 22, 23, 24–25, 28 whale sharks, 40, 79, 79, 106 Wimprine, Ted, 120–21 yellowhead jawfish, 19 zooxanthellae, 4, 18

East Flower Garden Bank