The effects of temperature on oxygen consumption of eggs and hatchlings of the nile crocodile (Crocodylus niloticus)

Abstract

1. The oxygen uptake ( ) of eggs and hatchlings of the Nile crocodile was measured at ambient temperatures (Ta) of 25, 32 and 37°C. 2. At a Ta of 32°C, was found to be stable during the last month of incubation. It, howe increased with 15% after hatching. 3. Embryos and hatchlings increased their O2, following exposure to increasing temperatures. At Ta, between 25 and 32°C Q10 were 1.83 and 2.3 for the eggs and hatchlings, respectively. The Q10decreased to 1.27 for the eggs but that of hatchlings increased to 2.59 at Ta between 32 and 37°C. 4. Exposure of eggs to pure oxygen at Ta of 37°C was accompanied by an increase in metabolism ( O2) to a level similar to that of hatchlings kept in air. 5. It is postulated that a combination of high temperature and environmental oxygen may reduce the incubation time of the crocodile eggs.