Breeding experience affects condition: blood metabolite levels over the course of incubation in a seabird |
| |
Authors: | Christina Bauch Susanne Kreutzer Peter H Becker |
| |
Institution: | (1) Institute of Avian Research “Vogelwarte Helgoland”, An der Vogelwarte 21, 26386 Wilhelmshaven, Germany |
| |
Abstract: | In vertebrates little is known about causes and correlates of differences in individual body condition. This is, however,
essential if we are to gain an understanding of environmental influences on wild populations. To track changes in individual
physiological state we analysed blood metabolite concentrations in breeding common terns Sterna hirundo. We selected birds to contrast sex, breeding experience, sampling year and nutritional state and collected repeated samples
from individuals during incubation. Unlike cholesterol, triglyceride and uric acid levels strongly correlated with nutritional
state. While cholesterol levels in males remained stable throughout incubation, comparatively lower levels were measured in
females directly after egg-laying. In 2006, only highly experienced females showed increased cholesterol concentrations by
mid-incubation, whereas less experienced females maintained reduced levels and were apparently unable to recover. In 2007,
all females showed an increase in cholesterol by mid-incubation. Triglyceride levels did not differ between sexes, but concentrations
were significantly higher in more experienced birds and were overall higher in 2007 than in 2006. Uric acid concentrations
did not differ significantly. The variation in cholesterol and triglyceride levels can be explained by differences in foraging
conditions, as food abundance, onset of breeding and mean clutch size indicate 2007 to be the superior year. Thus, environmental
conditions and breeding experience play an important role for cholesterol and triglyceride levels as well as the physiological
state. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|