Chameleons on the move: survival and movement of the Cape dwarf chameleon, Bradypodion pumilum, within a fragmented urban habitat

Abstract

Reptiles have an amazing diversity of life-history attributes ranging from the shortest- to longest-lived of vertebrate species. Estimating survival in wild populations is of key importance when understanding population dynamics and life-history evolution. However, data are lacking for a large and charismatic group of lizards, the chameleons. We conducted a Robust Design (RD) capture–mark–recapture (CMR) experiment on the Cape dwarf chameleon, Bradypodion pumilum, at two nested sites within the Cape Town Metropolitan Area, South Africa, in order to estimate survival and movement of adults in and around an isolated 3.5 ha patch of suitable habitat. Over a nine-week period, 97 individuals were identified in 379 captures from five primary capture sessions with three secondary events each. Analysis of CMR data provided evidence that smaller chameleons have a substantially lower survival per 10-day period than larger chameleons. RD analysis showed that males were more prone to temporary emigration than females, while open multi-strata analysis revealed that smaller chameleons more readily moved between the sites than larger chameleons. Our findings offer first important insights into chameleon survival and life-history dynamics, which suggest a more vagile subadult population and the possibility of male biased dispersal. Our results have implications for managing the conservation of threatened chameleon populations in highly fragmented urban habitats.

African Zoology 45(1): 99–106 (April 2010)