
%0 Journal Article
%A Olsen, Penny 
%A Baker, G. Barry 
%T Daytime incubation temperatures in nests of the Nankeen Kestrel, <emph type="2">Falco cenchroides</emph>
%J Emu
%D 2001/10/04
%V 101
%N 3
%P 255-258
%K 
%R https://doi.org/10.1071/MU00050
%U https://www.publish.csiro.au/paper/MU00050 
%X Telemetric eggs were used to monitor daytime incubation temperatures at Nankeen Kestrel, Falco cenchroides, nests on the outskirts of Canberra, Australia. During monitoring, only the females incubated. Once the second-last egg in the clutch was laid incubation began in earnest and temperatures averaged about 37&#x02DA;C. Incubation temperature was not constant; rather, it varied according to the day of incubation and showed marked variation over the course of the day and between individuals. On average, temperatures increased about 0.6&#x02DA;C per day until five days after the first egg was laid. After this, average temperature began to level off but continued to increase throughout incubation, at a rate of about 0.2&#x02DA;C per day. Mean temperature was positively correlated with chick condition at banding; we suggest that this was because better-fed females have little need to hunt and can thus maintain higher mean temperatures. At successful nests the eggs were incubated for about 73% of observation time, less than for kestrels&#8217; colder-climate congeners and suggesting that for kestrels in warmer climates such as in Australia the costs of incubation may be comparatively low. 
