Crocodiles, like most reptilian species, are ectothermic and thus rely on external heating for warmth and survival. Therefore by extension, it can be concluded that crocodiles will be more active in the warmer summer months and fairly lethargic during the cooler winter months. A study by Wallace and Leslie 2008 proved that juvenile C.niloticus had relatively emptier stomachs during the winter months in comparison to the summer months proving that this species was more energetic during the warmer period. A further study conducted by Seebacher and Grigg in 1997 found that crocodiles that thermoregulated during different seasons, preferred body temperature correlated with changes in water temperature concluding that crocodiles are more frequent in warmer, tropical waters.
C.niloticus lead a diurnal lifestyle however they are predominantly active after dusk. During the day crocodilians illustrate a range of behaviours including basking, moving between land and water
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