14 Steven P. Platania, Gilbert S. Grant, David S. Lee 



through the abdominal wall near the caudal part of the sternum deep 

 into the viscera. The maximum time between downing of the bird and 

 the insertion of the thermistor probe was 2 minutes. Body temperature 

 (T^) recordings stabilized within a maximum of 30 seconds of probe 

 insertion. In order to determine if stress and shock affected core body 

 temperature, readings were taken from any still-living birds before death 

 and within 1 to 3 minutes of being shot. We also monitored the rate of 

 cooling of six specimens for 20 minutes after death. Birds were later 

 frozen in sealed plastic bags. After thawing in the laboratory, each bird 

 was weighed to the nearest 0.1 g and sexed while being prepared for use 

 in other studies. Level of significance is 0.05 for correlation coefficients 

 of regressions and sample differences (using Student's /-test). Data are 

 presented as mean + 1 standard deviation. 



RESULTS 



Table 1 presents deep body temperatures and body mass of 23 spe- 

 cies of seabirds representing 4 orders, 14 genera, and 250 individuals. 

 Mean T^ of male and female seabirds (Table 2) were not significantly 

 different. In Audubon's Shearwater, Puffinus Iherminieri, and Cory's 

 Shearwater, Calonectris diomedea, the only species with a field collect- 

 ing base spanning 6 to 9 hours, Tu did not vary with time of day. How- 

 ever, we made no night collections. In both of these shearwaters, as well 

 as in the Greater Shearwater, Puffinus gravis, Tu did not correlate with 

 time of year. These three species were collected during the longest 

 calendar sequences (April-November). Additionally, intraspecific regres- 

 sions of body mass versus Tu were not significant. 



Cooling curves were obtained on six birds ranging in size from 39.7 

 to 763.5 g (Fig. 1). As expected, large birds cooled more slowly than 

 small ones. For example, in the first 20 minutes internal temperatures 

 dropped less than 0.8 °C on Pterodroma-s'ize birds. Four of six birds 

 showed a slight and brief increase in Tu during the first minute or two. 

 We think this temporary increase was the result of continued cellular 

 heat production immediately after death in the absence of convective 

 (respiratory and circulatory) avenues of heat loss. This initial increase in 

 temperature may mask some heat loss owing to the elapsed time 

 between death and T^ measurements. However, temperatures of living 

 birds and recently dead ones showed no observable differences (Table 

 3). 



DISCUSSION 



In collecting temperature information we attempted to eliminate as 

 many biases as possible. Activity states of the birds immediately prior to 

 temperature measurements undoubtedly accounted for some of the 

 variation in the procellariiform birds whose body temperatures were 

 summarized by Warham (1971). The difference between resting/ incubat- 

 ing and active procellariiform birds amounted to about 2 °C (Farner 



