02. Investigating the behaviour and enclosure use of zoo-housed Cuvier’s dwarf caiman Paleosuchus palpebrosus

The welfare needs of reptiles in zoological collections are generally less well understood than those of other taxa. Crocodilians represent an excellent opportunity to study a commonly-housed, conservation-dependant zoo animal. We studied the behaviour and enclosure use of five dwarf caimans Paleosuchus palpebrosus through day and night, at two British zoological collections; the enclosures had either six or seven identifiable zones. Time of day, mean temperature and collection were used as predictors of behaviour and enclosure usage. Camera traps recorded the position and behaviour of caimans at 30-second intervals. At each zoo, 80 hours of data were collected from which we constructed activity budgets and calculate a relativised Electivity Index of enclosure usage. The results identified that water-based perching, floating, swimming, immobile water behaviour and underwater behaviour were significantly affected by time of day, and that collection and temperature were good predictors of some behaviours. As for enclosure use, zone 3 (shallow water) was slightly overutilised in both collections, while all other zones were underutilised. Time was a significant predictor of the use of zones 3, 5, 6 and 7. There is considerable scope for future research on crocodilians in zoos.