Breeding season survival and breeding incidence of female Mottled Ducks on the upper Texas gulf coast

Waterbirds
By:  and 

Links

Abstract

Previous Mottled Duck (Anas fulvigula) studies suggested that high female breeding season survival may be caused by low nesting effort, but few breeding season estimates of survival associated with nesting effort exist on the western Gulf Coast. Here, breeding season survival (N = 40) and breeding incidence (N = 39) were estimated for female Mottled Ducks on the upper Texas coast, 2006–2008. Females were fitted with backpack radio transmitters and visually relocated every 3–4 days. Weekly survival was estimated using the Known Fate procedure of program MARK with breeding incidence estimated as the annual proportion of females observed nesting or with broods. The top-ranked survival model included a body mass covariate and held weekly female survival constant across weeks and years (SW = 0.986, SE = 0.006). When compared to survival across the entire year estimated from previous band recovery and age ratio analysis, survival rate during the breeding season did not differ. Breeding incidence was well below 100% in all years and highly variable among years (15%–63%). Breeding season survival and breeding incidence were similar to estimates obtained with implant transmitters from the mid-coast of Texas. The greatest breeding incidence for both studies occurred when drought indices indicated average environmental moisture during the breeding season. The observed combination of low breeding incidence and high breeding season survival support the hypothesis of a trade-off between the ecological cost of nesting effort and survival for Mottled Duck females. Habitat cues that trigger nesting are unknown and should be investigated.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Breeding season survival and breeding incidence of female Mottled Ducks on the upper Texas gulf coast
Series title Waterbirds
DOI 10.1675/063.035.0208
Volume 35
Issue 2
Year Published 2012
Language English
Publisher The Waterbird Society
Contributing office(s) Coop Res Unit Atlanta
Description 10 p.
First page 260
Last page 269
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page