I16 K t P T l L t S A N D AMPHIBIANS

I n r . %,lo )’h. ( 1989) 2 8 I 1 h - I22 S T h e Zoological Society of London

Breeding and maintenance of the Mauritius lowland forest day gecko

at Fresno Zoo Phelsuma g. guirtiheaiti

SEAN MCKEOWN Curator of‘ Reptiles, Fresrio Zoo, 894 West Belniont Ave, Fresno, California 93728-2891, C’SA

Madagascar and faunally associated islands of the western Indian Ocean are well known for their exceptional endemic wildlife. Perhaps no group within the Gekkonidae of the region is more spec- tacular than the brilliantly coloured day geckos Plielsurna of which there are 34 species and 24 subspecies (Cheke, 1981; Bohrne & Meier, 1981; Borner & Minuth, 1982). The taxonomy of this genus is constantly in a state of flux owing to recent discoveries of new forms or proposed revision of taxa previously described (Gardner, 1984; Digney & Tytle, 1986). With one exception, all species of day gecko are endemic to Madagascar. the Comoros. Mauritius, Reunion. the Seychelles and other islands of the Indian Ocean. One species inhabits the Andaman Islands in the Bay of Bengal. In recent times two or more species have become established, through the agency of man, in several port cities on the east coast of Africa (Vinson & Vinson. 1969; Miller, 1982). Two species. P. gi,qas and P . edwardnewtoni, from the island of Rodrigues. 588 km east of Maur- itius. are presumed extinct (Vinson & Vinson. 1969). Their demise is the result of modern man’s destruction of the native forest and introduction of non-native animals, including rats. on to Rodrigues.

The loss of species illustrates the fragi- lity of island ecosystems (McKeown. 1984). With severe habitat loss through- out much of the region, captive propaga- tion and management techniques learned

through it could play a key role in the long-term survival of these ‘jewels of the Indian Ocean’.

Within their geographic range Phel- suma utilise a variety of habitat types. Although most day geckos live on pan- tropic vegetation. certain inland and montane species in Madagascar and two of the Mauritius taxa, P. g . guimbeaui and P. g . rosagularis, exploit different niches (McKeown, 1983).

During two six-week periods in 1981 and 1982 the author conducted field studies on Pkelsuma in the Seychelles and the Mascarenes. The purpose of this field work was to study the behaviour of day geckos in the wild and to apply what was learnt to their management in captivity. During the past eight years seven taxa of Phelsunia have been maintained and captive bred on a long-term basis by the author in two zoological collections. This paper will focus on the management of the most difficult of these to house and propagate successfully, the Mauritius lowland forest day gecko P. g. guiniheuui.

WILD STATUS The island of Mauritius has an area of 1865 km, is volcanic in origin and lies 145 km distant from Reunion and 850 km east of Madagascar (Vinson, 1976). Before human settlement in 1598 dense stands of forest covered over 90% of the island. According to Jones (unpubl.) less than 1% of the original vegetation remains. Phtdsuma g . gzrirtiheaiti is confined

REPTILES A N D AMPHIBIANS 117

to small ‘islands’ of surviving suitable vegetation. It occurs in three remaining types of vegetation: mature unbroken stands of Terminalia, Mangifera and other broad-leafed trees bordering lowland stream drainages on the west and south- west side of the island; mature stands of partially degraded native forest in the interior at mid-elevation; the very few areas of sugar-cane land where clusters of the coconut palm COCO nucifera have been planted. It does not utilise other pan-tropic vegetation as do the much more widely distributed P . cepediana and P. 0. ornata (McKeown, 1983).

Typically P . g . guimbeaui live in trees in colonies consisting of one or more adult

and several 99 with members of each sex having a specific social ranking (McKeown, 1984). As the sun’s first rays illuminate the trunk and large branches, adults emerge from tree cavities or under loose bark to bask. Upon emergence the lizards are charcoal or grey coloured. As the light intensifies the drab colours are replaced by iridescent emerald green with splashes of blue, and bright orange mark- ings consisting of spots, dashes and lines. Adults spend much of the day basking or moving between sun and shade on the tree trunk and primary branches. Subadults live further out on the main branches while larger juveniles typically utilise the foliage on the outer limbs of the trees. Eggs are laid in trunk cavities under loose bark or at the base of leaves. Communal nesting does occur in choice protected locations. Predation from endemic and introduced birds is heaviest on neonates and small juveniles, and they seldom venture far from grooves and crevices in the tree bark. At this age they are capable of varying their colour only between char- coal and grey, and do not begin to develop the capacity for green skin colour until they are two-and-a-half to four months of age. Both juveniles and adults are insectivorous and frugivorous. They also feed on pollen and nectar and through these activities serve as pollina- tors for a number of flowering plants.

TRANSPORT AND ACCLIMATISATION Day geckos are prone to stress in transit but most species, including P. g. guim- beaui, can be transported without diffi- culty if separated by sex and size and carried by hand in well-ventilated plastic tubes. Crumpled paper towels placed inside the tubes give the lizards a place to hide and a sense of security.

Proper acclimatisation is extremely important and even in zoological collec- tions is often inadequate. Phelsuma should not be quarantined in 3.8 litre jars or other small holding containers which are especially ill-suited for 99 and juve- niles. In our experience the least stressful method is to move them direct from the transport containers to their permanent enclosures.

HOUSING FOR ADULTS Two taxa of delicate and easily stressed day geckos, P. g . guimbeaui and P . ornata inexpectata, are currently maintained in breeding colonies at the Fresno Zoo. Both are managed similarly and housed indoors in specially designed screen and wood frame enclosures. Three sizes of enclosure are used for breeding groups of adult P.g.guimbeaui: Model A, the largest, is 62 x 120 x l5Ocm high; Model B is 45 x 92 x 150 cm high (Plate 1); Model C is 75 x 60 x 75 cm high (Plate 2). The two larger models are on rollers enabling them to be repositioned for ease of access. A number of key components are present in all the enclosures and, we believe, contri- bute to their success. They are: 1. two horizontal 8cm wide wooden basking strips are nailed to the under- surface of the top of the frame and extend the length of the enclosure 7 cm below the screened enclosure top and equidistant and parallel to the light source; 2. two metal shop light fixtures rest on top of each model directly over the basking strips; 3. two fluorescent tubes consisting of one BL blacklight and one Vita-Lite are used in each fixture attached to an automatic timer;

118 RElTILES AND AMPHIBIANS

Plate 1 . Mauritius lowland forest day gecko Phelsuma g.guiniheaui breeding enclosure Model B. This view shows the key components before the fibreglass screening has been stapled to the wooden frame. s. McKeo\l~,l

4. two wooden strips 6cm wide extend diagonally from the floor below the door to the upper rear frame of the enclosure; 5. a large planter 30 x 30 x 30 cm is built into the centre of the enclosure; 6. a large live Dracaena marginata plant that reaches the height of the basking station is used in the planter; 7. a single door is present at one end of the enclosure.

The A and B models house 1.4 to 1.6 adults, while the C model houses 1.4 adults. The enclosures are designed to allow for several feeding stations as well as equal and horizontal basking stations, with a number of pathways to each. As a result specimens with patches of ripped skin or serious injuries received during

Plate 2. The Mauritius lowland forest day gecko breeding enclosure Model C.

courtship, which have been reported when Phelsuma have been housed together in conventional enclosures or terraria, have never been seen at Fresno Zoo. Our enclo- sures allow each member of the social unit to establish a large overlapping territory. The lizards interact principally by avoiding one another or by showing dominant or submissive body postures when another lizard approaches.

A single keeper-entry door is advisable as it affords the lizards the opportunity to maintain flight distance. Only minor disturbance is caused when the enclosures are serviced by the zoo staff.

DIET AND NUTRITION Inadequate nutrition shows itself in a number of ways, one of the first being complete absence of reproduction. If calcium carbonate is not supplemented, 99 will quickly stop their normal egg- laying cycles. Rickets may develop through lack of calcium carbonate or vitamin D (or both), particularly in $29 and juveniles.

At the Fresno Zoo dietary supplemen- tation has eliminated such conditions. Twice a week slices of scored papaya on to which shaved cuttlebone, an excellent

REPTILES AND AMPHIBIANS 119

source of calcium carbonate, has been sprinkled are placed on both feeding plat- forms in the adults’ enclosure. Since the diet has been supplemented, the 99 have laid year round, are robust and without skeletal deformities. Juveniles need calcium for skeletal development. Adult 88 use some but expel most of the excess. A stores calcium in endolymphatic or ‘chalk’ sacs located on the sides of the neck and the size of these sacs can be used to determine calcium reserves (Tytle, 1986). Bloxam & Vokins (1978) report that supplementing with cuttlebone (cuttlefish) eliminated a soft-shelled egg problem with the co-generic P. guentheri at the Jersey Wildlife Preservation Trust. In the wild day geckos partially replenish calcium by consuming the shells of hatched eggs from previous clutches but at Fresno we find that eggshells usually remain uneaten, an indication that high calcium levels are maintained.

Insects, dusted with either Theralin puppy vitamin-mineral supplement or Super Preen bird vitamin-mineral supple- ment and shaved cuttlebone, are fed to the geckos every other day. These include first stage crickets Acheta domestica, vesti- gial-winged fruit flies Drosophila and one- third grown waxmoth Galleria larvae. The number of insects offered at any one time is the quantity that the lizard will com- pletely consume within ten minutes of the food being presented.

WATERING, HUMIDITY AND TEMPERATURE Water dishes have obvious drawbacks for diurnal arboreal geckos and are not used. The plants in each enclosure are misted twice daily in the morning and afternoon and the lizards lap the water off the leaves. Humidity in the enclosure is controlled by moistening the earth substrate and the soil in the planter daily.

The rooms housing the geckos are maintained at a temperature of 29°C during the day and 25°C at night. The lizards, however, have a choice of temperature gradients and can increase

their body temperature markedly by basking under the natural spectrum lighting either on the plants or on the horizontal basking strips, a mere 7 cm below the light source.

SUBSTRATE The topsoil floor covering can be watered to increase humidity. The enclosure floor should be free of dead leaves or debris, where an ailing adult or hatchling can hide undetected. A well-managed enclo- sure floor also prevents a build up of undusted surplus insect food. Sand or gravel should never be used for substrate as both can be ingested and may lead to intestinal blockage and death.

PROPAGATION Courtship and breeding usually occur very soon after a 8 is introduced to a group of $29. Courtship consists of, but is not limited to, the 8 advancing and mak- ing a series of lateral head jerks and tongue flicks, followed by close contact head jerks and tail shakes by the 0; the 6 then nips the skin in the 0’s neck region, positions himself and inserts one of his hemipenes into her cloaca.

A gravid 9 appears robust. When she is viewed from below the outline of the two eggs can be seen through the ventral surface of her body. Day gecko eggs are moist when laid and are shaped into the proper configuration and sometimes even ‘egg rolled’ into the proper position with the hind feet.

In a captive environment, a protected location is the most important consider- ation when wild-caught ?? select a nest site. Captive-hatched 99 are less rigid in their selection. If the eggs are laid at the base of a leaf surface they can be gently removed and artificially incubated. The eggs which can be detached are placed in a small container. We use a top from a film canister, which is rested on a 4cm layer of slightly moist vermiculite in a lidded clear plastic container. Lukewarm water is added to the vermiculite at inter- vals of several weeks as necessary to keep

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i t at a two parts vermiculite to one part water consistency. Eggs laid on any hard surface will adhere and must be incubated in situ. Since proper humidity is essential, the eggs must be covered. We use a hard, clear, plastic receptacle with tiny airholes punched in one end and containing a small piece of folded paper towel which is misted with lukewarm water three times a week. The plastic cover is fastened into position with push pins. An added advan- tage of clear plastic is that the neonates are visible after hatching. In our breeding colonies of P . g. guimheaui, eggs are laid throughout the year. When incubated between 2629°C. hatching time is 40-45 days with ten days either side reflecting individual variation. Usually the offspring of this subspecies hatched within this temperature range are '?(;. During 1987 we purposely incubated the last two clutches of the year at 22.8-23.9"C to determine whether the eggs would hatch at these lower temperatures, and whether the sex ratios would be changed. Hatching times varied from a low of 97 days to a high of 128 days for the two clutches. While it is too early to make a definite assessment of sex the four subadults from eggs brooded at the cooler temperature also appear to be

MANAGEMENT OF HATCHLINGS A N D JUVEKILES Rearing hatchlings of large, non-stress- prone species of day geckos, such as P. niatiugast~urii~t~~si.~, P. suntlhergi, P . stand- iigi and P . gurntlleri. is relatively simple owing to their considerable size at birth, outgoing disposition and readiness to feed upon a variety of invertebrates and baby food. The rearing of the smaller stress-prone species is an entirely different matter. Offspring of P. g. guiniheaui average only l.9cm in snout-vent length and 2.9cm in total length as hatchlings and are extremely shy and flighty. Additionally. they are prone to desiccation.

The few zoos and private collections with this taxon have experienced high mor-

Plate 3. Rearing enclosure for neonates and small juveniles containing many built-in hiding places for the young geckos.

tality with neonates maintained entirely indoors. This necessitated the develop- ment of new housing and feeding strate- gies. At Fresno Zoo a rearing enclosure was designed which provided security and multiple hiding areas while affording the lizards an unobstructed view of the feeding station (Plate 3 ) . The rearing enclosures are 45 x 35 x 35 cm high and made from wood, with screened panels on two sides for staff viewing and a screened top for passage of UV light. The solid areas created by this design provide hiding places which are similar to the natural trunk crevices used in the wild. Branches are wedged against the sides of the frame and are used by the juveniles for basking and for moving to their respective territories. The rearing enclosures rest 1 cm below BL blacklights.

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In addition to special housing, proper food presentation is also required. Neonates may refuse live insect food for up to nine days after hatching. During the first two weeks of their life, a large slice of scored papaya lightly dusted with cuttle- bone and Theralin is always present at the feeding station on the bare wooden floor of the enclosure. It is replaced daily to ensure that it is fresh. Supplementing papaya in this way is crucial to early development of the neonates. In licking the fruit at irregular intervals throughout the day, they obtain essential moisture and nutrients. When they do begin feeding on insects they are offered newly hatched pinhead-sized crickets and vesti- gial-winged fruit flies dusted with Theralin and shaved cuttlebone every other day. Watering and misting techniques are criti- cal. It is necessary to mist the screened panels and half of the enclosure heavily, once in the morning and once in the after- noon, to provide drinking water and to keep the humidity levels high. Up to five neonates or small juveniles of similar age and size can be maintained together in each enclosure.

Once the geckos reach three months of age they become much less skittish and are relatively easy to manage. At this stage they can be transferred to conven- tional well-planted terraria until they grow to adult size and are ready to be moved into breeding enclosures.

In October 1986 there were 19(2.14.3) Lowland forest day geckos at the Fresno Zoo from four separate founder groups. All adults were F1 and F2 animals and

later increased once again to 13 hours. During 1987 49(0.45.4) geckos hatched from 33 separate clutches of eggs. In 1988 a third breeding colony was established with an unrelated 6 and four F2 and F3 09. During the first ten months of 1988 32 P. g . guimbeaui have hatched from 23 separate clutches of eggs laid in the three enclosures. The offspring from each col- ony have been kept in separate enclosures to ensure proper identification and genetic management in the future.

Reports summarising the Fresno Zoo’s reproductive efforts have been sent to the Mauritius Department of Forestry and Wildlife. In 1987 we discussed the possibi- lity of releasing 50 captive-bred Mauritius lowland forest day geckos into one of the parks within the species’ historic range offering a suitable habitat. The site is separated by several miles of housing and sugar-cane fields from the closest existing wild populations and permission from the Conservator of Forests and Wildlife has been received. If funding is available we will initiate the release during 1989.

ACKNOWLEDGEMENTS

I am grateful to our Director, Paul S. Chaffee, DVM, for his support of this captive breeding programme and to Scott Ransom, Mary Morgan, Dana Knepper and Harold Mountan for reviewing the manuscript.

PRODUCTS MENTIONED IN THE TEXT

BL Blacklight: F20 and F40, manufactured by North American Philips Lighting Corporation. Bloomfield, NJ 07003, USA. Super Preen: vitamin-mineral powder with amino acids for birds, manufactured by RHB Laboratories

were descendants of specimens collected Inc., 1640 East Edinger Avenue. Santa h a , CA 92705, USA.

in an area c’800 50 a stream Theralin: vitamin-mineral powder for puppies, drainage in western Mauritius. manufactured by Lambert Kay, Division of Carter

In preparation for increased breeding Wallace Inc., Cranbury, NJ 08512, USA. activity during 1987 1.4 and 1.6 adults Vita-Lite: T-12-24 and 48 inch, manufactured by were housed in the two off-display Duro-Test Corporation, 1501 Doolittle Drive, San

Leandro, CA 94577, USA. breeding enclosures. The 66 were unre- - ~~

lated to each other and to each group of 99. On 1 November 1986 the light cycle for each was shortened to ten hours. On 2 January 1987 the light cycle was increased to 12 hours and six months

REFERENCES BLOXAM, Q. & VOKINS, M. (1978): Breeding and maintenance of Phelsuma guentheri (Boulenger, 1885) at the Jersey Zoological Park. Dodo, J. Jersqv Wildl. Preserv. Trust 15: 82-91.

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BOHME, W. & MEIER. H. (1981): Eine neue Form der madaguscuriensis-Gruppe der Gattung Phelsuma von den Seychellen (Reptilia: Sauria: Gekkonidae). Salamandra 17: 12-19. BORNER, A.-R. & MINUTH, W. (1982): Advance diagnoses of new taxa of the Phelsuma madagascariensis group. Misc. Artic. Saurol. No. I I : 1-19. Cologne: A.-R. Borner (private publication). CHEKE, A. S. (1981): What the book does not tell you about day geckos: some comments on Oostveen’s Phebumas on new species and on recent research. Herptile 6 4-10. DIGNEY, T. & TYTLE, T. (1986): Calcium metabolism in the lizard genus Phelsuma: a preliminary report. In Proceedings 91h inrernaiional herperological syniposium on captive propagation and husbandry: 175-183. Caporaso, F.. McKeown. S. & Peterson, K. H. (Eds). Thurmont, MD: Zoological Consortium. GARIINER. A. s. (1984): The evo/utionarj, ecology and popularion sysiemurics of day geckos (Phelsuma) in rhe Seychelles. Unpublished Dissertation, University of Aberdeen. JONES, C. G. (Unpublished): The conseruaiion of the endemic. h i d and bars of Mauririus and Rodrigues. 1981 Annual Report to the WWF Project 1082. Black River. Mauritius. MCKEOWN. S. (1983): Wild status and captive management of Indian Ocean Phelsuma with special

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reference to the Mauritius lowland forest day gecko (Phelsuma g . guimbeaui). In Proceedings 6th annual reptile symposium on captive propagation and husbandry: 157-170. Marcellini, D. (Ed.). Thurmont. MD: Zoological Consortium. MCKEOWN, S. (1984): Management and propagation of the lizard genus Phelsuma. Acta zool. path. antwerp. 7 8 149-161. MILLER, M. J. (1982): Phelsumas: A case of monotypic care of a polytypic genus. In Proceedings 5th annual reptile symposium on captive propagation and husbandry; 103-1 18. Marcellini, D. (Ed.). Thurmont, MD: Zoological Consortium. TYTLE. T. (1986): Calcium metabolism in the lizard genus Phelsuma: a preliminary report. In Proceedings 9th international herpetological symposium on captive propagation and husbandry: 175-183. Caporaso, F., McKeown, S. & Peterson, K . H. (Eds). Thurmont, MD: Zoological Consortium. VINSON, J.-M. (1976): The saurian fauna of the Mascarene islands. 2. The distribution of Phelsuma species in Mauritius. Bull. Maurit. Inst. 8 177-195. VINSON, J. & VINSON. J.-M. (1969): The saurian fauna of the Mascarene islands. Bull. Maurii. Inst. 6 203-320.

Manuscript submitted 13 December 1988

l t l i ZOO 1.h ( 1989) 28: l??-l?6 ( The Zoological Society of London

Maintenance and breeding of the Superb dragon

at the Australian Reptile Park, Gosford Diporiphorii .superha

JOHN WEIGEL Head o f Reptile k v t i o n . Aitstruliun Reptik Park, Gosford, N S W 2250, Australia

The Superb dragon Diporiplioru sicperhu is a member of the Agamidae family, a group of some 300 species distributed throughout the Eastern hemisphere, of which about 50 are found in Australia. The family includes some of Australia’s most spectacular and unusual reptiles living in a wide variety of environments. Scientifically described in 1974, the Superb dragon is confined to rocky areas

within the Kimberley district of the tropical northwest. The species is known only from a handful of museum speci- mens and it is unlikely to have ever been maintained in captivity. It has a small, elongated body (up to 95mm) and an extremely long and narrow tail, approxi- mately four times the length of its body (Plate I ) . The digits are also very long, contributing to the reptile’s bizarre ‘stick