Pleistocene reptile swim traces confirmed from South Africa’s Cape south coast

arge Pleistocene reptile tracks and traces were described from the Cape south coast of South Africa in 2020, including ‘probable swim traces’. These trace fossils were found on loose slabs and blocks of the Klein Brak Formation. Subsequently, another surface has become exposed on this coastline, also on a loose slab. It exhibits more definitive evidence of swim traces in epirelief, probably made by the Nile crocodile (Crocodylus niloticus) or water monitor (Varanus niloticus), although a chelonian origin cannot be excluded. Length of a possible crocodylian trackmaker was estimated from measurements of interdigital distance in the swim traces. These provide a compelling example of reptile swim traces from Africa.

Evaluating the Effect of Visitor Presence on Nile Crocodile (Crocodylus niloticus) Behavior

Visitor presence has been shown to affect the behavior of animals in zoos. However, studies to date have not included a wide range of taxonomic groupings, and thus, the effect is poorly understood for many species. Here, we compared the behavior of Nile crocodiles (Crocodylus niloticus) in the presence and absence of visitors for the first time. Data were collected at Disney’s Animal Kingdom® over two months during normal operating conditions and during the same two months the following year when the park was closed due to the COVID-19 pandemic, totaling 158 observation hours. Significant differences in crocodile behavior were observed between park operating conditions; however, the direction of change varied by behavior and average differences were generally small. In addition, we found that time of day, temperature and month significantly affected behavior, often with greater magnitude than visitor presence. This highlights the importance of accounting for environmental variables when evaluating and interpreting the behavior, and ultimately welfare, of reptiles in zoos. Collectively, the data suggest the overall effect of visitors on crocodile behavior was small and neutral from a welfare perspective. This study highlights the importance of taxonomic diversity in studying the visitor effect.

Ranching Lake Nasser’s Nile Crocodiles

The Nile Crocodile Crocodylus niloticus is the most widely distributed crocodile species in Africa, occurring in almost all sub-Saharan countries. It was included in Appendix I in 1975. Egypt submitted a proposal (no. 9) to the IUCN at the Conference of Parties (CoP) no. 15 to transfer the Egyptian population of C.niloticus from Appendix I to Appendix II for purposes of ranching