Video nest monitoring reveals male coloration-dependant nest predation and sex differences in prey size delivery in a bird under high sexual selection |
| |
Authors: | Diane Colombelli-Négrel and Sonia Kleindorfer |
| |
Institution: | (1) School of Biological Sciences, Flinders University, GPO Box 2100, Adelaide, 5001, Australia; |
| |
Abstract: | Increased predation risk should select for reduced parental activity to decrease the probability of visually hunting predators
discovering the nest. Parental activity and conspicuousness are known to increase predation risk. Here, we test for sex differences
in parental visitation rate (number of visits), time seen at the nest (time at the nest × adult visibility), and food delivery
(prey size) using continuous video recordings at nests. We test the role of these variables for predation outcome in the Superb
Fairy-wren (Malurus cyaneus). The study species is sexually dimorphic: males have iridescent blue plumage while females have brown plumage. The results
showed that nest predation was predicted by male time seen at the nest (but not visitation rate), but not female time seen
at the nest (or visitation rate). Contrary to our expectation that males would have lower visitation rates than females, our
analysis of video images showed that male and female visitation was comparable but that males consistently brought smaller
prey items to the nest than females. These findings are discussed in the light of morphological differences between male and
female beak size. We conclude that sexual selection has favoured conspicuous male signalling in this system, and that natural
selection should select for reduced parental care for the conspicuous sex. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|