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USGS · 1002659

Survival of female northern pintails wintering in southwestern Louisiana

Robert R. Cox·Alan D. Afton·Richard M. Pace
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Abstract

The North American breeding population of northern pintails ( Anas acuta ) has reached previously unprecedented low numbers 4 times since 1983. Because pintails show high fidelity to wintering areas, regional survival estimates and identification of factors influencing survival are needed to guide management of wintering pintails. We used radiotelemetry to estimate survival rates of female pintails wintering in southwestern Louisiana. We tested for variation in survival and hunting mortality rates in relation to age (immature or adult), winter (1990-91, 1991-92, 1992-93), time period (prehunting season, first hunting season, time between split hunting seasons, second hunting season, posthunting season), body condition (body mass when released, adjusted for body size), and region (southwestern Louisiana or elsewhere on the Texas-Louisiana Gulf Coast or Mississippi Alluvial Valley). Within southwestern Louisiana, the 147-day (5 Oct-28 Feb) survival rate of adults (0.714 ± 0.045; x̅ ± SE) was greater ( P = 0.02) than that of immatures (0.550 ± 0.068), primarily because immatures had higher hunting mortality. Female survival was lower ( P s < 0.01) during hunting than during nonhunting seasons but did not differ between first and second hunting seasons ( P = 0.58) or among non-hunting seasons ( P s >0.25). Survival did not differ in relation to winter or condition ( P s > 0.12). Hunting mortality did not differ ( P s > 0.13) in relation to winter, condition, or region, but hunting mortality of immatures (0.287 ± 0.046) was greater ( P < 0.001) than that of adults (0.130 ± 0.025). Despite conservative hunting regulations (30-day seasons and 1 pintail daily), hunting mortality rates of pintails in southwestern Louisiana were high. Pintails in southwestern Louisiana rely on a small number of key refuges for protection but feed almost exclusively in privately owned agricultural fields. If increased winter survival of female pintails in southwestern Louisiana is desired, we recommend that managers increase food available.

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Journal of Wildlife ManagementArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 29.641129744623527° to 30.951638691147664° latitude; -93.69021130572173° to -92.03700568803214° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

Robert R. Cox, Alan D. Afton, Richard M. Pace. 1998. Survival of female northern pintails wintering in southwestern Louisiana. https://doi.org/10.2307/3802018

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