tetraspis distributed in the Upper Guinea bioregion of West Africa. that recognized three lineages in the genus Osteolaemus, namely, Osteolaemus osborni restricted to the Congo Basin, Osteolaemus tetraspis found in the Lower Guinea bioregion of west Central Africa and yet to be named Osteolaemus sp.
However, an update of the Red List status may be necessary following the taxonomy revision by Eaton et al. Dwarf crocodiles are categorized as vulnerable on the IUCN Red List and all populations are on Appendix I of the Convention on International Trade in Endangered Species (CITES) checklist. Throughout its range, African dwarf crocodiles are experiencing rapid population declines due to unregulated harvesting for food and habitat destruction often for agricultural purposes. African dwarf crocodiles typically inhabit forest streams, isolated pools, and swamps where access to sunlight is limited. IntroductionĪfrican dwarf crocodiles (genus Osteolaemus) are relatively small, secretive, and docile crocodilians that are endemic to western Africa from the Democratic Republic of Congo to The Gambia. Efforts should be made to repeat the study across this species’ range for an improved understanding of its nesting ecology. Generally, dwarf crocodiles selected forest patches within the highly disturbed landscape for nesting indicating the need to protect the remaining forest patches. Three nests were destroyed by flood and one by an unknown predator suspected to be a West African Nile monitor lizard. The mean nesting success and hatching success across the two seasons were 77.8% and 75.3% (SD = ±41.9, n = 18), respectively. We found a mean clutch size of 8 eggs per nest (SD = ☒ range = 5–13 n = 17) supporting previous reports that this genus has a low clutch size. The findings from this study suggest a weak positive to no correlation between dwarf crocodile incubation temperature and ambient temperature indicating nest temperature is almost independent of ambient temperature. The daily mean incubation temperature recorded during the study was 30.7☌ (±SD = 0.8☌, n = 240, range = 28–33☌) and it is congruent with the reported value for the species. We used Hobo tidbit® data loggers to monitor egg chamber temperature and the effect of ambient temperature on nest temperature. We monitored 18 nests from the 20 nesting seasons in the Chirehin Community Land-a highly disturbed agricultural matrix in the climatic transition zone of Ghana.
We describe incubation temperature, nesting success, hatching rate, and clutch size of West African dwarf crocodiles. Despite this, many questions about their basic ecology remain unanswered and this inadequate data hampers effective dwarf crocodile management.
tetraspis) are among the most threatened crocodilians in the world due to unregulated hunting and habitat loss-related population decline.
West African dwarf crocodiles ( Osteolaemus sp.