The General Care and Maintenance of Green Water Dragons, Sailfin Lizards and Basilisks (General Care and Maintenance of Series) 1882770145, 9781882770144

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The General Care and Maintenance of

Green Water Dragons, Sailfin Lizards and Basilisks by

• Philippe de Vosjoli

The Herpetocultural Library

Series 100

Published by: Advanced Vivarium Systems Lakeside, CA 92040, USA. Copyright© 1992 by Philippe de Vosjoli All Rights Reserved. No part of this book may be reproduced in any form without the permission of the author. Cover by Tamandra Michaels.

The General Care and Maintenance of

Green Water Dragons, Sailfin Lizards and Basilisks by

Philippe de Vosjoli

Table of Contents Introduction ... .................... .................. .. ................................ ..... 1 Green Water Dragons ........................................ ... ......... ..... ........ 2 Housing and Maintenance ........................................................... 7 Feeding...................................................................................... 11 Breeding .... ....... ........ .. ............................. .. ........... .......... ........... 12 Diseases and Disorders ............................................................... 16 Sailfin Lizards .. .......................................................................... 20 Selecting Potentially Healthy Sailfin Lizards .............................. 23 Housing and Maintenance of Sailfin Lizards ........ .. ..................... 25 Basilisks .................................................................................. ... 27 Source Materials ......................................................................... 31

Introduction In recent years, herpetoculturists have been fortunate in having the opportunity to keep and work with some of the large agamid lizards from southeast Asia, notably green water dragons and the Philippine sail fin lizards. Among these, green water dragons rank as some of the best lizards for keeping in captivi ty because oftheir attracti veness, relati vely calm disposition and adaptability. Captive breeding of water dragons is OCCUlTing with increasing frequency and, hopefully, more serious efforts will be made in this area to ensure the long term availability of these wonderful lizards. Sailfin lizards, whose care is very similar to that of water dragons are altogether a different breed of animal. While these large lizards have a striking and impressive appearance, they are asocial and wary with a greater tendency for "crazy" flight behaviors that can result in damaged snouts and digits. Some extra effort, particularly in providing suitably designed large enclosures will be necessary for the maintenance of these lizards in captivity. The appeal of sailfin lizards lies in the dragon-like appearance of the males, their large yet very reptilian eyes, and a subtle coloration which can include various hues of blue. This book is dedicated to the care, maintenance, and breeding of these Asian lizards in captivity. In addition, a section has been included on the basilisk lizards of the New World, not because they are related to these lizards (they're not) but because their care is very similar to the two aforementioned species. Aknowledgments: Special thanks to Chris Estep for photographs of his water dragon breeding colony and to Chris Lindberg for sailfin lizard photographs and information.

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Green Water Dragons These semi-arboreal lizards from Southeast Asia are still imported in large numbers for the pet trade in spite of the fact that they are now protected in several countries. As lizard pets, green water dragons rank among the very best of the larger lizards. They are attractive, handleable, they display well, often adapt well to captivity, do not grow too large and will also readily breed in captivity. Compared to green iguanas, green water dragons have the advantage of not growing nearly as large. As a rule, they are somewhat calmer than iguanas. There is of course also a difference in respective personalities. Iguanas tend to demonstrate more responsive awareness and more signs of intelligence than water dragons. However, a somewhat less responsive personality has certain advantages. Green water dragons compared to green iguanas are less likely to stress out when moved to a new enclosure. Green water dragons unlike iguanas can also be displayed in large, attractive planted vivaria and are less likely to damage landscape plants and materials than most other large lizards.

NEED FOR MANAGEMENT In countries where they occur, green water dragons could become a significant economic resource if managed properly. Without proper management, this species could easily become threatened as a result of habitat destruction and overexploitation. Green water dragons have been exploited for food and, more recently, to supply the reptile pet trade. As a result both adults and juveniles are under hunting/collecting pressure. Sound management policies should attempt to protect natural habitats, implement collecting seasons and possibly establish quotas. Managed field harvesting may be the most economical method for sustained yield. The relatively low reproductive rate of green water dragons, combined with the relatively low current market prices do not make the development of the commercial herpetoculture of these lizards economical at this point in time. However, should sound management policies fail to be implemented, commercial herpetoculture of green water dragons is feasible and should be encouraged. Although future prices for these lizards may one day be many times greater than they are at the present time, the many qualities of the green dragon will continue to make it a highly desirable species even at higher prices. To assure the future availability of these lizards, all private herpetoculturists interested in green water dragons are encouraged to maintain breeding pairs or groups. Why not breed these animals while they are still available? Two or three water dragons, except for the extra space required, are really not much more work than keeping one.

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GENERAL INFORMATION Green water dragons are among the largest members of the Old World family Agamidae. The scientific name of the green water dragon is Physignathus cocincinus. Two other Physignathus occasionally offered in the herpetocultural trade are the Australian water dragon, Physignathus lesueurii and the small southeast Asian Physignathus temporalis.

Distribution: Green water dragons are found on the southeast Asian mainland and the Indo-Australian archipelago. Most imported specimens are from Thailand or southern China. Size: Large male water dragons can achieve total lengths just over three feet. Females are typically smaller. Sexing: With age, males develop comparatively larger heads, large jowls and a larger crest behind the neck. The femoral pores of adult males are slightly larger than that of females.

SELECTING POTENTIALLY HEALTHY GREEN WATER DRAGONS 1) A void large adult imported water dragons. These are often in poor condition (thin and with rubbed snouts) and do not adapt as well as smaller animals. Generally, the importation of large adults should be discouraged. Ideally, they should be left in the natural habitat where they can breed. On the other hand captive-raised adults are a good choice. 2) When available, select young animals 10 to 16 inches in length. If they appear healthy (see below) when imported, many of these adapt quite well to captivity. As a second choice, select healthy appearing hatchlings but expect a somewhat greater mortality rate compared to captive-raised larger individuals. 3) Before picking out an animal, check that its eyes are alert, that its body and tail are rounded and that it is active. 4) Pick up the animal. Examine the body and tail thoroughly for lumps or swellings or serious damage to the skin. Next look at the limbs, hands, feet and digits. Make sure that none of these are swollen or damaged. Look at the head and particularly the snout. Make sure that there is no serious damage to the snout. Gently tap the snout of the lizard to encourage it to open its mouth (very gently; forget this procedure if the lizard doesn't do this after two or three taps). Look inside the mouth for any signs of swelling, bubbly mucus or caseous (cheesy-looking)

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Close-up of the head of a male green water dragon (Physignathus cocincinus). Notice the enlarged jowls and nuchal crest.

Close-up of the head of a female green water dragon.

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deposits along the gum line. A void animals with any of these symptoms. Turn the animal over and look at the vent. It should not be swollen. Check for any smeared or caked diarrhea around the vent. Avoid animals with any of these symptoms.

NUMBER OF ANIMALS PER ENCLOSURE Green water dragons and Australian water dragons can be kept in groups of one male and up to four females. In room sized enclosures, two or three males and several females can be kept together. Males are not very aggressive with each other in these two species. Typical interactions involve head bobbing followed by a male being chased by another. These behaviors are more prominent during the breeding season. It is a good idea to carefully monitor respective males kept together. Subdominant males may spend a large amount of time hiding and may therefore 110t feed adequately. Stress should be considered as a possible cause of decline.

A pair of captive-raised water dragons and a female green basilisk. In large enclosures these species are compatible.

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Underside of a mature male green water dragon. Notice the enlarged femoral pores compared to the female's.

Underside of a mature female green water dragon.

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Housing and Maintenance SELECTING AN ENCLOSURE All glass aquaria with screen tops are suitable for keeping water dragons. A criterion for enclosure size is that an enclosure should be at least twice the length of the animal(s) being kept and preferably larger. In terms of commercially sold aquaria the greater the width, the better. Although a ten gallon aquarium is suitable for a hatchling, you should initially purchase an enclosure at least 30 inches long (29 gallon) which will be suitable for about 18 months. After that time, you should consider purchasing the final vivarium for your animal(s). Following the guidelines for size mentioned above, this means that at least a six foot, one hundred gallon aquarium will be required for keeping an adult pair of water dragons. The alternatives are to custom build enclosures of wood with a glass front. The wood should be coated with several coats of polyurethane or epoxy paint. An advantage to custom made enclosures is that it allows you to provide a greater width and height than normally available in all glass aquaria. It also allows one to add greater height for plants and branches as well as front opening doors to facilitate cleaning, maintenance and access to the animals.

DESIGNING THE VIVARIUM Water dragons are tropical, semi-arboreal lizards that live near water. Their enclosures should have diagonally placed branches as resting areas, a medium that can retain some moisture, a large water container or water section, adequate light and adequate heat. For display purposes, plants can be included.

GROUND MEDIA In vivaria, water dragons can be maintained on small grade orchid bark or on a mixture consisting of 2/3 peat moss based potting soil and 1/3 sand. Water dragons have also been maintained successfull yon artificial grass carpets such as Astroturf®.

LANDSCAPING Several branches with a diameter nearly equal to that of the girth of the body of the animals maintained should be placed diagonally in the vivarium to provide suitable climbing and resting areas. Rounded natural cork bark sections are highly recommended as branches for these vivaria. Cork is attractive and can be disinfected when necessary by dipping in a solution of 5% bleach for at least 15 minutes then rinsing out with water.

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PLANTS In addition to diagonal branches one can use live dragon plants (Dracaena). Many species including the "cornstalk plant" (Dracaena fragrans massangeana) of horticulture tend to do well with water dragons. If planted at an angle within the pots or in the ground medium, the trunks can provide natural looking resting areas. For decorative purposes, other plants can be used for backgrounds such as cut-leaf philodendrons (Monstera deliciosa) or pothos (Scindapsus aureus). Epiphytes such as staghorn ferns (Platycerium species) can be grown on sphagnum moss attached to the walls of the vivarium. Over time, some damage from scratching will occur to the plants, and they may have to be removed and replaced. Removed plants can be grown in the house until they generate new leaves. These can then be used as replacement plants in the future.

TEMPERATURE Green water dragons should be maintained at temperatures of 84°-88°F during the day with a drop to 75° -80°F at night. Commonly used methods for heating water dragons are subtank heating pads, heating cables and incandescent spotlights. When using incandescent spotlights, a thermometer should be used to assure that the temperature of the underlying basking area closest to the bulb does not exceed 90°F. To prevent thermal bums, any spotlights should be placed in such a way that lizards cannot come into direct contact with them.

ADDITIONAL LIGHTING Full spectrum bulbs are highly recommended but not required for keeping green water dragons in captivity. There are psychological benefits in using this type of lighting. These should be the lighting of choice for illuminating their vivaria. UVB generating black lights or sunlamps are usually avoided by green water dragons and should only be used for brief exposures if at all.

WATER Water dragons should have water available at all times. A container large enough for water dragons to readily enter and immerse themselves up to 50% of their body height should be available. For adults, large plastic cat litter pans are good choices for water containers. The container should be sunk into the ground medium in such a way that green water dragons can readily enter or exit the container. The container should be easy to remove for cleaning, disinfecting and replacing of water. Ideally, the water in the container should be changed daily although every

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A custom-built enclosure containing a trio of green water dragons. Note the branches, heat source, thermometer and large water container.

A male water dragon basking under a spotlight.

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two days is adequate as long as the animals haven't defecated in the container. A common pattern is for water dragons to splash around and defecate within minutes of having introduced a fresh pan of water. The pan should be cleaned and removed within a half hour and clean water reintroduced. A positive aspect of this is that water dragons are so consistent in defecating in their water containers that one seldom has to replace the substrate.

MAINTENANCE The standard maintenance of water dragons should include a daily quick visual check to assess the health status of the animal(s) , replacing water and feeding as needed, watering the plants and cleaning the glass of the vivarium. The substrate should also be replaced as needed. This will depend on the size of the vivarium but in a large enclosure two to three times a year is all that is required and in a very large enclosure, once a year is more than enough.

GROOMING If you intend to handle your water dragon, you will find it necessary to occasionally clip the tips of their nails using a standard nail clipper. When clipping nails, avoid cutting the vein that runs through the nail. This can be seen under good lighting as a dark line running through the middle of the nail.

HANDLING AND ESCAPES Established green water dragons will usually allow themselves to be picked up and handled for brief periods of time. They do not ,as a rule, enjoy extensive periods of handling and petting. Green water dragons should never be taken outdoors on one's shoulder or ann or kept loose or unrestrained. You will be amazed at the speed with which your calm water dragon can take off if given the opportunity. Exposure to the great outdoors and sunlight can make a " tame" water dragon decide to hop off and run bipedally on its hindlegs at a speed that will make it difficult to capture. Heed this warning.

A large water container such as a concrete mixing tub or a large cat litter pan will be required to maintain water dragons.

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Feeding In captivity, green water dragons are primarily carnivorous but will also eat a significant amount of plant matter. The following are recommended diets.

HATCHLINGS AND JUVENILES Offer 2 to 3 week old crickets which should be vitamin/mineral supplemented at every other feeding. Also offer finely chopped or grated fruits and vegetables which will be taken by some lizards. The crickets should be maintained on a high quality diet such as ground rodent or monkey chow and a high protein baby cereal or tropical fish flakes prior to feeding to the lizards. As a source of water, offer sections of orange to the crickets. As they grow larger, give the young water dragons correspondingly larger crickets and occasionally wax worms and small meal worms. Eventually you can offer occasional day old pink (newborn) mice and as they grow older, fuzzy mice. With younger animals, it is preferable to offer 3 to 4 small food items at a feeding instead of a single large food item. A criterion for selecting the size of a food item is that a prey item should be no longer than the length of the head and no wider than half the width of the head and preferably about one third of the width of the head.

ADULTS Adult water dragons should be fed small mice, adult crickets and king meal worms (Zophobas). Large water dragons should also be offered some plant matter: thawed mixed vegetables, bananas, strawberry, melon, etc. Some will also eat soaked monkey chow, but this should only be offered in very small amounts making up 10% or less of the diet.

VITAMIN/MINERAL SUPPLEMENTATION All insects and plant matter should be dusted with a vitamin/mineral reptile supplementtwo to three times a week for hatchlings and juveniles and once a week for adults if these are maintained on a diet that include fuzzy to weaned mice. With hatchlings and juveniles, it is recommended that the insects also be coated once to twice a week with a calcium/vitamin D3 supplement such as Osteoforme ®.

FEEDING SCHEDULES Hatchling and juvenile water dragons should be offered food every two days. Subadults and adults should be fed every three to four days.

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Breeding When -maintained properly, green water dragons will readily breed in captivity_ For breeding, the recommended procedures are as follows: -The animals should be at least two years old and two feet in total length. -The animals should have good weight and appear healthy. -For two months during late fall or winter, the photoperiod should be reduced to 10 hours daylight/14 hours darkness. The daytime temperature should be reduced to 75°-78°F with the high spot under an incandescent spotlight at 80°-84°F. The nighttime temperature should be reduced to 68° -74 OF. Feeding should be reduced to once a week and food offered in late morning or midday. Following this fall/winter rest period, green water dragons should be placed back on a normal schedule of temperature, photoperiod and feeding. Breeding behavior by males will be observed within a few weeks consisting of the chasing of female(s), head bobbing and attempts at copulation. The breeding behavior consists of the male seizing the female by the nuchal crest (above the neck) and lightly twisting the body to insert a hemipenis. Copulations last from 10 to 20 minutes. Removing females from the males' enclosures for a week and reintroducing them into the male's cage during the breeding season can increase the number of successful copulations. Females will lay eggs about two months after copulations have occurred. As gestation progresses and more and more of the abdominal cavity is taken up by developing eggs, some females will show a preference for small prey items instead of a large prey item such as a weaned mouse.

EGG· LAYING AND INCUBATION A layer of sandy peat moss 8-10 inches deep should be placed in the enclosure for gravid females to lay their eggs. If you place a board or a section of cork bark on top of the peat/sand area, many females will diga nest starting at the edge of these structures and end up digging a burrow underneath. Once a female has laid eggs, the eggs should be carefully dug out and removed to a suitable incubator. For incubation, the eggs should be placed in an incubator such as Hovabator ® in moistened vermiculite (equal amounts of vermiculite to water by weight or 10parts vermiculite to one part water by volume). The eggs should be buried on their sides with two thirds buried in the vermiculite and one third exposed above the vermiculite. The eggs should not be turned during the entire incubation period so

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mark the tops with an x using a magic marker if you think the eggs may get disturbed. A layer of moistened sphagnum moss should be placed on top. The eggs should be maintained at 84°-86°F. Mader (1987) recommends an incubation of 88°F but the author (p.O.) suspects that this may be in the upper limits of-suitable temperature and that upward fluctuations could prove fatal in the latter stages of development when the oxygen demands of metabolism at high temperatures may exceed the oxygen that can pass through the egg shell and membranes. In addition to the above, it is recommended that the surface of the eggs be lightly misted every one to two days. This procedure recommended by Mader (1989) contributed in 100% hatching by the author (p.O.) of several clutches of green water dragon eggs. An easy to construct incubator consists of obtaining at least a standard twenty

gallon aquarium, adding 3 to 3 1/2 inches of water and introducing a 75 watt submersible aquarium heater. Bricks or a frame made of welded wire is added to allow the placement of a plastic storage box filled with the appropriate medium for incubation to be included. With the help of a thermometer placed inside the storage box, the temperature is adjusted using the thermostat on the heater. A custom-made lid of polystyrene should be placed on top of the aquarium and at least an hour allowed prior to and between adjustments of the thermostat. A useful tool for these incubators are the electronic digital thermometers sold in electronic supply stores. You can place the sensor for an outdoorreading inside the container and the digital display thermometer, which is kept on the outside, will give a continuous reading of your incubation temperature. Hatching of green water dragons will occur under the above conditions after about 65 days. The lizards will hatch over a period of twenty four to forty eight hours.

CAUSES OF HATCHING FAILURE The most common complaint of prospective green water dragon breeders is hatching failure of full term embryos/lizards. The author suspects that upper limits in incubation temperature may be one cause of hatching failure. There are other possible causes which deserve investigation. One cause involves the moisture level of the incubating medium. Being too wet or too dry will affect the internal pressure of the egg as well as the condition and turgidity of the eggshell, and therefore the ease with which a ready to hatch lizard will be able to rupture the shell. Finally, (this is an area which many of us involved in lizard breeding are beginning to focus on) there is the strong possibility that the health and diet of the mother has a significan t effect on the subsequent nutrition available to the embryo (i.e. amount of yolk, possibly the quality of nutrition available) and on the structure of the eggshell. Feeding adult animals a quality and varied diet appears to be important. Careful monitoring of one's animals and keeping detailed records on husbandry and incubation methods can provide invaluable information that will allow you to

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make the adjustments necessary for success. Whatever you do, don't give up. We all need to work on establishing breeding populations of these wonderful lizards in captivity.

Green water dragon eggs in a simple incubator using a submersible water heater. The careful calibration of the temperature using a thermometer inside the container with eggs will be critical for successful incubation.

Side view of the incubator when sealed. The temperature was set at 86 F. It was reduced to 84 F after 7 weeks of incubation.

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Green water dragons hatched using the methods recommended by the author.

Enter the dragon.

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Diseases and Disorders MAKING DECISIONS ON VETERINARY MATTERS A common question among many herpetoculturists is whether it is worth taking an animal to a veterinarian when the costs of treatment will often exceed many times the cost of the animal and when in many cases the animal will die anyway (a common scenario with sick lizards). In the case of most reptiles, the wisest course when dealing with imported animals is to have an animal checked early on for parasites or bacteria in the stools. Early diagnosis and prevention is always the best course of action with reptiles. Subsequent decisions will have to be made on a case by case basis.

As a general rule hatchlings and small animals that are very sick and look like they may die usually do eyen with verterinary intervention. On the other hand adult lizards, particularly water dragons, often respond well to veterinary treatment. The key is to seek treatment early on when the first signs of a problem become apparent. Being in tune with one's animals is what makes a good herpetoculturist.

INTERNAL PARASITES Both juvenile and subadult imported water dragons typically harbor parasites. If your animals fail to gain or maintain weight in spite of feeding well and/or if your animals have diarrhea or discolored stools, your should take a stool sample to a veterinarian to determine what parasites may be present and the best course of treatment.

METABOLIC BONE DISEASE OR CALCIUM DEFICIENCY This disease complex popularly known as calcium deficiency is not uncommon in captive young water dragons. One of the worst cases the author has seen was in an adult raised primarily on un supplemented insects. The earliest and most obvious symptom in young animals is a soft, flexible lower jaw which makes feeding difficult. In larger animals, more severe symptoms will include fibrous osteodystrophy characterized by swollen hind limbs and eventually the inability to move normally. The cause is lack of physiologically available calcium either because of lack of calcium in the diet or because of inadequate calcium to phosphorus ratio or lack of vitamin D3 that allows the animals to absorb calcium. If you followed the guidelines for feeding and vitamin/mineral supplementation indicated in this book, you will not have this problem. Treatment consists of providing adequate calcium and D3 orally or in severe cases, the animal can be taken to a verterinarian for treatment with injectable calcium.

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Male Australian water dragon (Physignalhus lesueurii). This species is bred in very small numbers in the U.S. Winter cooling with temperatures at night dropping into the low 60's appears to be required for successful breeding.

Gravid female Australian water dragon.

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ROSTRAL RUBBING OR DAMAGED SNOUTS A common problem in captive green water dragons is their tendency to damage or injure their snouts. The notion of glass wall, screen wall and even solid wall is not readily comprehended by green water dragons (this is not true of Australian water dragons). As a result, they run into walls when panicked or even simply moving about their cages. If the wall is glass or screen, they will rub their snouts in their attempts to get to the other side. This tendency has little to do with size of the cage. Individuals captive-raised from juveniles are less likely to rub their snouts. Placing barriers along the sides of the enclosures, in the form of plants or landscape structures will reduce the incidence of snout rubbing.

STOMATITIS OR MOUTHROT In water dragons, this disease is usually prevalent in the area of the snout usually as a consequence of damage from rubbing or ramming against a cage wall. Nonetheless, many water dragons do a good job at fighting any infection. When mouth rot is present, it will be visible as white caseous (cheesy) material in the infected area. Treatment consists of gently removing any caseous material, washing out the infected area with Betadine ® and applying an antibiotic ointment such as Neosporin ®. This procedure should be done every one to two days until the infection has cleared.

SWOLLEN AND INFECTED LIMBS In the course of their activity, water dragons can injure limbs and digits. In captivity, toenails are sometimes lost, the tips of digits may get infected or infections may develop in a hand or foot. In most cases, the best course of action is to take your animal to a qualified veterinarian specialized in treating reptiles. Standard treatment involves incising the infected area, removing pus and caseous matter, flushing with hydrogen peroxide and Betadine® solution and administering antibiotics.

ARTICULAR AND PERI-ARTICULAR GOUT OR PSEUDO GOUT Hard swellings of the joints of digits that eventually involve the entire hand or foot of a green water dragon will sometimes occur in captive animals. The symptoms are identical to those of gout or pseudogout and all four limbs may be involved. Eventually deformities result in problems that prevent normal movement. There are no effective treatments. To date, the author has seen this type of problem primarily in a small number of males. The possible dietary cause has not been determin_ed but providing a varied diet and clean water on a regular basis may prevent this.

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RESPIRATORY INFECTIONS Many imported water dragons die of undiagnosed respiratory infections. Like birds, reptiles often do a good job at not demonstrating obvious signs of illness until a disease has progressed to the point that it cannot be easily treated. Symptoms of water dragons with respiratory infections include listlessness, reduced appetite, swollen appearance of body and, when the disease has progressed, gaping followed with occasional forced exhalations. Prompt treatment will be required when these symptoms are noticed. The temperature should be raised to 85-88 F around the clock until symptoms subside. The lizard should be taken to a veterinarian and treated with appropriate injectable antibiotics.

GASTROENTERITIS Typical symptoms of gastroenteritis are loss of weight, listlessness, loss of appetite and diarrhea. There is only one solution here and that is to take your animal to a veterinarian and have the stools checked for parasites or bacteria. With early diagnosis, the prognosis is good but untreated this will usually prove fatal.

Captive-bred juvenile Australian water dragons. Photo by Glen Carlzen.

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Sailfin Lizards In recent years, sailfin lizards from the Philippines have been imported into the United States with some regularity. These impressive reptiles, though increasingly offered through the pet trade, are not always a good choice for beginning herpetoculturists. Sailfin lizards will grow to a large adult size and require large enclosures to fare well. Compared to other large lizards, such as green iguanas and green water dragons, sailfin lizards tend to be shy and nervous. Adults will suddenly demonstrate crazy flight behaviors and run into the sides of a vivarium. Like green water dragons, their awareness of glass or solid barriers is limited. These behaviors can result in injured snouts and digits. For those who truly appreciate the beauty, form and personalities of these animals and are willing to put effort into the design of their vivaria and their maintenance, sailfin lizards will make outstanding display animals and rewarding reptile pets.

GENERAL INFORMATION NEED FOR ECONOMIC HERPETOCULTURE Sailfin lizards are hunted in large numbers for food in their native countries. In the Philippines, there is now collecting pressure on both adults (for food) and juveniles (the pet trade). Unless the wild populations are managed through some type of wildlife agency, there is a risk that at least two of the three species could one day become threatened. It would be best if these species were recognized as economic resources and effective management programs implemented which would allow for sustained harvesting without threatening the status of existing populations. Possibly, a combination of population management in the field combined with more controlled herpetoculture could be effective. Possible directions for management could include. -Establishing a hunting/collecting season that would prevent collection or hunting of animals during the entire reproductive season. -Setting bag limits during the collecting/hunting season, at least on adults. -Encouraging the development of the economic herpetoculture of these species.

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WHAT'S IN A NAME? The name saHfin lizard has been used in the pet trade and refers mainly to the large tail crest of the males of these species. The scientific name of the sail fin lizards imported in large numbers from the Philippines is Hydrosaurus pustulatus. There are two other species of Hydrosaurus both of which are occasionally imported: the soa-soa Hydrosaurus amboinensis from the Celebes, Moluccas and New Guinea, and Weber's sailfin lizard Hydrosaurus weberi from the Moluccas. The validity of these species has been questioned, and it has been suggested that Hydrosaurus may consist of only two species. Size: The sailfin lizards (Hydrosaurus) are the largest members of the family Agamidae. Males of the soa-soa and of the Philippine sailfin lizard can reach a total length of three and a half feet. Females tend to be smaller than males. Sexing: Young males can be recognized by the development of tail crest buds which in captivity will begin to appear in animals starting at about six months of age. In larger animals, the larger dorsal crests and large sailfin-like crests above the tails of males are an unmistakable characteristic. Other features include the enlarged nasal knob usually characteristic of males (although some females will also develop these knobs) and the enlarged femoral and pre-anal pores of male animals. Longevity: Up to ten years or more. There is a record of a soa-soa (Hydrosaurus amboinensis) fifteen and a half years old and still living.

Male Philippine sailfin lizard (Hydrosaurus pustulatus) captive· bred and raised at the St. Louis Zoo. Photo by Cliff Lindberg.

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Male Weber's sailfm lizard (Hydrosaurus weberi .) Photo by Cliff Lindberg.

Female Weber's sailfm lizard (Hydrosaurus weberi.) Photo by Cliff Lindberg.

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Selecting Potentially Healthy Sailfin Lizards The selection process is identical to that mentioned for water dragons.

PARASITES Because sailfin lizards are kept in overcrowded conditions prior to export and when housed by dealers in the U.S., parasites will often spread in a given group through feces, contaminated water and food. Sailfin lizards typically harbor several types of worms and may also be infected with protozoan parasites. Ideally, a stool check should be performed by a veterinarian and the parasites treated. See green water dragon under parasites.

HOUSING These are relatively asocial lizards. They are best kept singly or in single pairs in large enclosures. Males if kept together will fight. Young males will bite off the ends of tails of other males. Eventually weaker or subdominant animals become intimidated and stressed and eventually die. Larger animals can be quite aggressive. Females also compete when kept together. For breeding purposes, single pairs can be kept together or the sexes kept separate and the female(s) introduced in the male's enclosure. In very large enclosures, possibly more than one female can be kept but the animals should be monitored carefully for stress (typical signs include hiding most of the time, refusal to feed and increasingly listless behavior).

Juvenile Philippine sailfin (Hydrosaurus pustulatus). Photo by Cliff Lindberg.

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Like water dragons, sail fin lizards require water containers large enough that they can immerse tlleir entire bodies. Photo by Cliff Lindberg.

Egg-laying box for sailfin lizards with a 2-3 inch layer of moist sphagnum moss. Photo by Cliff Lindberg.

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Housing And Maintenance of Sailfin Lizards The overall design of a vivarium for sailfin lizards is similar to that of green water dragons except that very large enclosures five feet long and preferably larger will be required for keeping mature animals. A large water container should be provided as well as diagonally placed overhanging branches. Large plants such as Dracaena and Philodendron can be used to decorate the enclosure. Providing large branches, cork sections or plants near the walls of the enclosures will reduce the incidence of damaging flight behaviors. A large shelter should be provided. Otherwise heat, humidity, etc. will be similar to that required by green water dragons.

FEEDING The basic diet is the same as for water dragons but add extra plant matter as mentioned below. Sailfin lizards are omnivorous lizards. Juveniles tend to be primarily insectivorous but become increasingly vegetarian as they grow older. Adults are best fed a varied diet of insects, small mice, rat pups and vegetable matter. Regularly offering a "salad" of various fruits, dark green lettuces and vegetables is recommended. Sliced grapes and melons are particularly relished by sailfin lizards. Vegetables such as yellow squash and carrots can be offered, but these should be shredded. A varied diet is recommended for these lizards.

As adults, at least 50 % of their diet should consist of vegetable matter. Vitamin/mineral supplementation: See green water dragon. Water: A large water container with a height about two thirds the height of the animal at rest is recommended. Clean water should be available at all times.

HANDLING Sailfin lizards should be handled with regularity if you want a somewhat tame lizard. Animals that are interacted with from the time they are juveniles tend to be calmer. Overall, these are wary and nervous lizards.

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BREEDING There are few records of captive breeding partially because relatively little effort has been done in this area. The low cost of imports at the time of writing doesn't justify the development of commercial breeding in the United States and, in the countries of origin, the management of wild populations would be a more effective and economical course of action. When considering breeding sailfin lizards, it is important to remember that these are generally asocial and highly competitive animals. Both males and females will try to achieve dominance over members of their sex. Submissive males and females in captive conditions usually show signs of stress and weight loss. If kept with the dominant animals, they usually die. So the best course of action for captive breeding is either to keep single pairs together or to keep animals individually and introduce individual females to individual males following pre-breeding conditioning (similar to green water dragons). Females captive-raised from juveniles will reach sexual maturity at two years and eventually lay eggs at least once a year. Pre-breeding conditioning is recommended in early winter. Breeding will occur in late winter or early spring, and egg-laying will follow in mid to late spring.

Number of eggs laid: 8-11 and possibly more in larger animals. Incubation: Similar to green water dragons. The recommended incubation temperature is 82°-85°F. The rearing of juveniles is similar to that of green water dragons. An easily accessible shallow pan of water should be provided. The juveniles should be misted daily. The initial diet should be vitamin/mineral supplemented 2 week-old crickets. At about three weeks, some finely chopped fruits and vegetables should be offered. By the age of three months, properly maintained animals will begin to take pink mice. Early segregation of the animals is recommended.

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Basilisks The following section on basilisk lizards has been included because of the similarity of care between these species and the previously mentioned lizards. As display lizards, few can match an outstanding male double crested basilisk (Basilisc us plumifrons). Except for size, these lizards with their impressive crests, bright yellow eyes, even green to pastel green coloration and turquoise blue spots, look like the closest thing to a living dragon one is ever likely to encounter. Captive-raised double-crested basilisks, because of dietary deficiencies in plant pigments that contribute to the normal coloration, are often an even turquoise blue. Large scale breeding efforts are currently in progress for the commercial production of Basiliscus basiliscus and Basiliscus plumifrons so the future availability of these spectacular lizards seems assured. Virtually all species of basilisks are occasionally offered in the pet trade with the rarest being the red-headed basilisk (Basiliscus galleritus). Basilisks belong to the family Corytophanidae . Four species are recognized:

-The common basilisk (Basiliscus basiliscus). Distribution: southern Central America to northwest Colombia.

-The red-headed basilisk (Basiliscus galleritus). Distribution: the Pacific slopes of Colombia and Ecuador to Panama and Costa Rica.

-The green or double crested basilisk (Basiliscus plumifrons). Distribution: Panama, Costa Rica and Nicaragua.

-The Central American Basilisk (Basiliscus vittatus). Distribution: Mexico through Central America and into Colombia. Size: The largest of the basilisks are male double crested basilisks which can have a total length of nearly three feet. The smallest are the Central American or striped basilisks. Growth: Under optimal conditions, basilisks born and raised in captivity will become sexually mature in 18-24 months.

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The author's adult wild-caught male green basilisk (Basiliscus plumifrons).

A gravid female green basilisk.

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Sexing: Males of all basilisks have pronounced crests adorning the back of the head. Male B . basiliscus and B. plumifrons also have highly developed dorsal (back) and caudal (tail) crests. Longevity: Up to ten years and possibly longer. Selection: See general guidelines under green water dragon

GROUPS OF ANIMALS PER ENCLOSURE Male basilisks as arule cannot be kepttogether as they are prone to vicious fighting resulting in injuries. When fighting doesn 'toccur,one will notice the decline from stress of subdordinate animals. Thus, only one male should be kept per enclosure. Depending on the size of the enclosure, more than one female can be kept with a male. Some breeders will house groups of one male and up to three females.

MAINTENANCE Similar to green water dragons.

FEEDING Similar to green water dragons except that adults with the exception of very large male double-crested basilisks don 'tgrow large enough to take weaned mice. Early stage fuzzy mice should be given instead. A varied diet is recommended. King mealwonns (Zophobas) can be used as the primary component of the diet with adults. Some plant matter containing yellow plant pigments is particularly recommended for green basilisks. Captive-raised animals of this species are often bluish presumably because of a lack of appropriate plant pigments in the diet. A lack of exposure to sunlight may also contribute to this

BREEDING Similar to green water dragons except that basilisks will not breed at a low relative humidity (minimum 80% and preferably higher). Under ideal maintenance, all species will double or triple clutch. B. plumifrons may lay up to four clutches of up to 16 eggs per clutch. The size of the clutches will partially depend on the age and the size of the females. B . basiliscus has been reported to lay up to 18 eggs andB . vittatus up to 14 eggs though the average clutch size for the latter is between 4 and 5 eggs.

EGG LAYING Similar to green water dragons.

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INCUBATION Similar to green water dragons.

REARING OF HATCHLINGS Similar to green water dragons except that males should be separated as soon as sexual characteristics and/or fighting becomes apparent.

DISEASES AND DISORDERS Similar to green water dragons.

A hatchling green basilisk hatched by the author.

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Source Materials 1. Alcala, A. 1986. Guide to Philippine flora and fauna. Vol X Amphibians and Reptiles/Natural Resources Management Center. Ministry of Natural Resources and University of Philippines. pp.87-88. 2. Demeter, B. U. 1981. Captive Maintenance and breeding of the Chinese water dragon. (Physignathus cocincinus) at the National Zoological Park. In proceedings of the 5th Annual Symposium on Captive Propagation and Husbandry. Oklahoma City Zoo. pp. 122-132. 3. Frye, F.L. 1991. Reptile Care: Atlas of Diseases and Treatments. T.F.H. Neptune, New Jersey. pp.650. 4. Lederer, G. An additional contribution to the ethology of the sail-lizard (Hydrosaurus amboinensis Schloss). Bulletin Chicago Herpetological Society Vol 22, No.9 pp. 152. 5. Mader, D.R. 1987. Captive propagation of the Chinese Water Dragon (Physignathus cocincinus). In Proceedings of the Northern California Herpetological Society's 1987 Conference on Captive Propagation and Husbandry of Reptiles and Amphibians. 6. Mitchell, L.A. 1985. Comments on the Maintenance and Reproduction of

Hydrosaurus pustulatus at the Dallas Zoo. In Proceedings of the 9th International Herpetological Symposium on Captive Propagation and Husbandry. pp. 185-186.

A captive hatched and raised Central American basilisk (Basiliscus vittatus).

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About the Author Philippe de Vosjoli was born in 1949 in Paris, France. When in his teens, he was introduced to naturalistic vivarium design by an eccentric former keeper at the Jardin des Plantes. Since that time he has pursued a life long interest in the husbandry and propagation of amphibians and reptiles. He earned his bachelor's degree at the University of Miami, Florida and has completed graduate studies in biology at Harvard University. He has authored and coauthored with Robert Mailloux several papers on the captive husbandry and propagation of frogs and lizards. In 1987 he founded the American Federation of Herpetoculturists, the non-profit organization which publishes the quality magazine The Vivarium, whose goals are to disseminate information about herpetoculture and represent the interests of herpetoculturists. His current research focuses on developing methods for sustained maintenance and propagation of tropical frogs, tiliquine skinks, green iguanas and various agamid lizards.

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Other books published by Advanced Vivarium Systems: Series 100 The General Care and Maintenance of Horned Frogs The General Care and Maintenance of White's Tree Frogs The Right Way to Feed Insect-eating Lizards The General Care and Maintenance of Ball Pythons The General Care and Maintenance of True Chameleons, Part I, Husbandry. True Chameleons Part IT, Notes on Popular species, Diseases and Disorders General Care and Maintenance of Leopard Geckos General Care and Maintenance of Box Turtles General Care and Maintenance of Red-Eared Sliders General Care and Maintenance of Green Anoles Series 200 General Care and Maintenance of Red-tailed Boas General Care and Maintenance of Burmese Pythons Series 300 A Color Guide to Corn Snakes Captive-Bred in the United States Series 400 Keeping and Breeding Corn Snakes Arachnomania: The General Care and Maintenance of Tarantulas and Scorpions The General Care and Maintenance of Savannah Monitors The Green Iguana Manual The General Care and Maintenance of Milk Snakes

ISBN

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J -882770-14-5 GW 0111

4886901110

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