TY  - JOUR
AU  - Viblanc V A, P. Bize
PY  - 2012//
TI  - Body Girth as an Alternative to Body Mass for Establishing Condition Indexes in Field Studies: A Validation in the King Penguin
T2  - Physiol. Biochem. Zool.
JO  - PHYSIOLOGICAL AND BIOCHEMICAL ZOOLOGY
SP  - 533
EP  - 542
VL  - 85
IS  - 5
N2  - ABSTRACTBody mass and body condition are often tightly linked to animal health and fitness in the wild and thus are key measures for ecophysiologists and behavioral ecologists. In some animals,such as large seabird species, obtaining indexes of structural size is relatively easy, whereas measuring body mass under specific field circumstances may be more of a challenge. Here, wesuggest an alternative, easily measurable, and reliable surrogate of body mass in field studies, that is, body girth. Using 234 free-living king penguins (Aptenodytes patagonicus) at variousstages of molt and breeding, we measured body girth under the flippers, body mass, and bill and flipper length. We found that body girth was strongly and positively related to body massin both molting (R2=0.91) and breeding (R2=0.73) birds,with the mean error around our predictions being 6.4%. Body girth appeared to be a reliable proxy measure of body mass because the relationship did not vary according to year and experimenter, bird sex, or stage within breeding groups. Bodygirth was, however, a weak proxy of body mass in birds at the end of molt, probably because most of those birds had reached a critical depletion of energy stores. Body condition indexesestablished from ordinary least squares regressions of either body girth or body mass on structural size were highly correlated (r=0.91), suggesting that body girth was as good as sbody mass in establishing body condition indexes in king penguins. Body girth may prove a useful proxy to body mass for estimating body condition in field investigations and couldlikely provide similar information in other penguins and large animals that may be complicated to weigh in the wild.
SN  - 1522-2152
UR  - http://dx.doi.org/10.1086/667540
N1  - exported from refbase (http://publi.ipev.fr/polar_references/show.php?record=4184), last updated on Wed, 10 Jul 2024 17:25:34 +0200
ID  - ViblancVA2012
ER  -