Comparing reproductive success of a colonial seabird, the Magellanic Penguin, estimated by coarse- and fine-scale temporal sampling

The condor

¹ 

关键词: fecundity;    Magellanic Penguin;    reproductive success;    Spheniscus magellanicus;    sampling frequency;    survey;   

DOI  :  10.1650/CONDOR-16-123.1

学科分类：动物科学

来源: Central Ornithology Publication Office

【 摘 要 】

ABSTRACT Fecundity, an important demographic variable for wildlife populations, is time consuming and expensive to measure. For seabirds, reproductive success is often estimated from 2 surveys of the colony, 1 during incubation and 1 during chick rearing. Using 33 yr of data on Magellanic Penguins (Spheniscus magellanicus), we compared reproductive success estimated from 2 surveys per season, from infrequent nest checks, and from daily nest checks to answer 4 questions: (1) Is reproductive success estimated from 2 surveys per season accurate enough for population models (within 15% of the ‘true' value)? We found that the answer was yes, if surveys were done on optimal dates and chick counts were adjusted by the percentage of chicks that were heavy enough to fledge. Optimal dates depended on the synchrony and phenology of the species. If penguins bred particularly late or early in a given year, estimates were wrong even if counts were done on the average optimal date. (2) Can counts of occupied nests be ad...

【 授权许可】

CC BY