Chameleons on the move: survival and movement of the Cape dwarf chameleon, Bradypodion pumilum, within a fragmented urban habitat
نویسندگان
چکیده
Reptiles have an amazing diversity of life-history attributes ranging from the shortestto 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.
منابع مشابه
Short communication Chameleons and vineyards in the Western Cape of South Africa: Is automated grape harvesting a threat to the Cape Dwarf Chameleon (Bradypodion pumilum)?
—The use of automated grape harvesters in the Cape Wine Growing region has resulted in controversy regarding their effect on the chameleon Bradypodion pumilum. We investigated densities of B. pumilum during harvesting at a vineyard near Stellenbosch, South Africa. During dedicated surveys, no chameleons were found in vines, while vegetation surrounding the vines contained densities as high as 1...
متن کاملForaging mode of the chameleon, Bradypodion pumilum : a challenge to the sit-and-wait versus active forager paradigm?
Foraging mode is an important aspect of life history, often associated with traits such as locomotor mode, energy budget, risk of predation and reproductive effort. Because of these life-history associations, classification of foraging mode can be conceptually useful. Lizards figured prominently in the historical development of foraging mode concepts, yet our current understanding is dominated ...
متن کاملTesting game theory models: fighting ability and decision rules in chameleon contests.
Game theory models of animal contests make many non-mutually exclusive predictions, complicating empirical tests. These predictions regard the relationship between contest parameters and fighting ability, for which body size is usually used as a proxy. However, in many systems, body size may be a limited proxy since multiple traits and contextual factors such as experience influence fighting ab...
متن کاملMorphology, ornaments and performance in two chameleon ecomorphs: is the casque bigger than the bite?
The evolution of ecomorphs within a species may represent either unique evolutionary events or multiple convergent events in similar environments. Functional studies of differing morphological traits of ecomorphs have been important to elucidate their role in adaptive radiations. The Cape dwarf chameleon, Bradypodion pumilum, has two ecomorphs: a large, brightly colored, ornate form found in cl...
متن کاملFunctional consequences of morphological differentiation between populations of the Cape Dwarf Chameleon (Bradypodion pumilum)
UMR 7179 CNRS/MNHN, Département d’Ecologie et de Gestion de la Biodiversité, 57 rue Cuvier, Case postale 55, 75231, Paris Cedex 5, France Applied Biodiversity Research Division, South African National Biodiversity Institute, Private Bag X7, Claremont, Cape Town, 7735 South Africa Department of Biodiversity and Conservation Biology, University of the Western Cape, Private Bag X17, Bellville 7535...
متن کامل