Round Island Day Gecko

Scientific Name: Phelsuma guentheri

Natural History:

Limited to the small, 375 acre, rat-free, dome-shaped islet of Round Island, 12.5 miles NNE of Mauritius. Before massive habitat destruction by humans and the introduction of rats, cats, and other predators onto Mauritius, circa 1600, this lizard occurred on the main island or Mauritius as well. It is now restricted solely to Round Island. the habitat on Round Island was severely degraded by rabbits and goats released in the 1800s. These Introduced mammals fortunately have now been eliminated. Inhabits fan palms (lantania), pandanus, and bottle palms. Sometimes encountered in and around rocky crevices. Although it may be out during the day, recent studies have shown that it is most active at night. Courtship is primarily during the summer. In the wild, females are colony nesters, selecting protected sites for egg deposition.

Biology:

Adult males average about 9.5 inches and females 9 inches. Large individuals are capable of reaching almost 1 foot. Adults are grey or brownish grey dorsally. Ventral surface is off-white. When basking, darker dorsal spots are present. A faint, dark-colored eye stripe is present from behind the nostril to above the ear opening. While generally somewhat plain in appearance, a few individuals in the wild have thin pale yellow barring on the toes and legs and very light mint green striping and barring on the dorsal surface, with off-white or light grey markings on the lips, throat, and flanks when in peak coloration. Juveniles of this species are typically light grey with a pattern of dark blotches and, in neonates and small juveniles, barring is present on the tail. the ventral surface is yellowish with dark brown barring.

Care:

This species is listed as endangered by the U.S. Department of the Interior and as Appendix I by the CITES. It has been legally exported only by the Jersy Wildlife Preservation Trust Zoo in England. Thus, it has only been bred by Jersy WPT and a few private herpetoculturists in Holland and Germany, with specimens on loan from Jersey. Those at Jersy WPT are housed in glass vivaria measuring 39.5 X 23.6 X 23.6 inches. VitaLites are used. the distance from lights to lizards is as little as 3 inches. Plants are maintained in enclosures in pots, and newspaper is used as substrate, for hygiene. Adult lizards are fed moths, including wax moth larvae and adults, butterflies, crickets, and grasshoppers, two times a week; once a week they are offered a fruit baby food mixed with vitamins and minerals. The lizards are housed both as sexual pairs and as individuals introduced in January during the peak breeding period

Breeding:

During courtship, the male arches his back, slowly flicking out his tongue, and moving his body in a series of rapid jerky motions, following which copulation takes place. During laying cycles, egg clutches average 35 days apart. One to two eggs are laid. these are glued onto the sides of the tank and must be covered and incubated in place. Incubation at Jersy WPT varies from 53-68 days. Females average one to four clutches a year. The young average 3 inches in total length and are reared in separate vivaria under VitaLites. For some reason not yet understood, the sex ratio of captive-bred offspring has been heavily skewed in favor of females.