thumbnail

Variation in body mass of wild canvasback and redhead ducklings

Condor

By:
,

Links

Abstract

We assessed variation in body mass of ducklings in single- and mixed-species broods of wild Canvasbacks (Aythya valisineria) and Redheads (Aythya americana) 20-50 days old. Body mass of canvasback ducklings was not affected by year and season (early vs. late hatch date) despite changes in water conditions. Mean body mass of male and female Canvasbacks did not differ in Class IIA but did differ in older age classes. Within-brood differences in body mass tended to be higher in Class IIA ducklings (6-7% of mean body mass for Canvasbacks, 9-11% in Redheads) and generally declined to 4-6% in Class IIC and older ducklings. Some within-brood differences were as high as 20-30% of mean body mass. Tests to assess sources of within-brood variation (age, sex, and season) in body mass for Canvasbacks were inconclusive. Variation within broods was generally less than that among broods for both Canvasbacks and Redheads. The lack of differences in duckling body mass between single- and mixed-species broods for any age class, sex, or species suggests that mass was not affected by interspecific brood parasitism.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Variation in body mass of wild canvasback and redhead ducklings
Series title:
Condor
Volume
96
Year Published:
1994
Language:
English
Contributing office(s):
Northern Prairie Wildlife Research Center
Description:
p. 909-915
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Condor
First page:
909
Last page:
915
Number of Pages:
6