Condor 98, 844-848 (1996)
Diving pattern and stomach temperatures of foraging king cormorants at subantarctic Macquarie Island
Kato, A., Y. Naito, Y. Watanuki and P. D. Shaughnessy
Logging stomach temperature in marine endotherms
has enabled the determination of when and how much
food has been ingested by free-ranging seabirds (Weimerskirch
and Wilson 1992, Wilson et al. 1992, Gremillet
and Plos 1994. Putz and Bost 1994). While considerable
errors in mass estimates caused by factors
such as position of the loggers and activity of the animal
can occur using this technique, the timing of prey ingestion
can generally be determined accurately (Wilson
et al. 1995).
We simultaneously recorded the diving depth and
stomach temperatures of free-ranging Ring Cormorants
(Phalucrocorax albiventer) using micro data loggers
with the goal of quantifying the variability between
the top and bottom stomach temperatures and comparing
methods to estimate meal mass in free-ranging
seabirds. Here we report on the advantage of using two
temperature sensors on the top and bottom of the loggers,
and the problems in determining the feeding activities
of seabirds from their stomach temperature.
BD96-01
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