ENCLOSURE UTILIZATION AND ACTIVITY OF ROUND ISLAND GECKOS (PHELSUMA-GUENTHERI)

This study evaluated space use and activity of individually housed Phe lsuma guentheri to formulate recommendations for environmental enrichm ent. Gecko location within small (0.03 m(3)) and large (0.22 m(3)) viv aria and substrate use data were collected over five 24 h periods. The rmogradients within each enclosure type were determined by measuring t emperature at various heights. From these data, geckos' space use, act ivity cycle, and substrate preference were calculated in relation to t emperature changes and photoperiod. Geckos did not utilize their envir onment uniformly. Heavily utilized locations contained cage furnishing s or hides. Geckos avoided the use of vertical glass walls. Thermograd ients were not actively utilized; however, when given the opportunity, geckos would orient towards natural sunlight. Enclosure size did not affect activity cycle, which was nocturnal with crepuscular peaks. Rec ommendations for enclosure improvement include provision of more furni shings and hides at different thermal levels. An alternate focal heat source other than UV light is recommended to provide warmth without li ght. Larger enclosures may encourage more uniform use of available spa ce. Transparent glass may not be an appropriate substrate for these ge ckos. Once recommendations have been implemented, a similar study must be conducted to assess benefit. (C) 1995 Wiley-Liss, Inc.