Data from: Variation in age ratio of midcontinent greater white-fronted geese during fall migration

Annual productivity is an important parameter for the management of waterfowl populations. Fall age ratio (juveniles:total birds) is an index of productivity of the preceding breeding season. However, differences in the timing of migration between family groups and nonbreeding birds may bias age-rat...

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Bibliographic Details
Main Authors: Schock, Wade G., Fischer, Julian B., Ely, Craig R., Stehn, Robert A., Welker, Jeffrey M., Causey, Douglas
Format: Dataset
Language:unknown
Published: 2018
Subjects:
Online Access:https://zenodo.org/record/5015435
https://doi.org/10.5061/dryad.28660
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Summary:Annual productivity is an important parameter for the management of waterfowl populations. Fall age ratio (juveniles:total birds) is an index of productivity of the preceding breeding season. However, differences in the timing of migration between family groups and nonbreeding birds may bias age-ratio estimates. We examined temporal variation in age ratios of midcontinent greater white-fronted geese Anser albifrons frontalis from interior and northwestern Alaska at a northern autumn staging area near Delta Junction, Alaska. Photographic sampling conducted near Delta Junction resulted in an annual age ratio of 0.388 ± 0.004 (mean ± SE) in 2010 and 0.390 ± 0.001 in 2011. Our study demonstrated temporal variation in age ratios over the duration of the migration period during August and September. We recommend that sampling be conducted for 3-d periods at the beginning, middle, and end of the migration period to account for temporal variation in migration of family groups. Data A1Microsoft Excel file which contains raw survey data for midcontinent greater white-fronted geese (Anser albifrons frontalis) migrating near Delta Junction Alaska during 2010 and 2011, organized in a single tab, "Data A1 – 2010-2011 Raw Data." The "2010-2011 Raw Data" tab contains date, time, total adults, total juveniles, total not identified, total sample, proportion of juveniles, age ratio, percent of birds identified and location.Reference A1Bromley RG, Rothe TC. 2003. Conservation assessment for the dusky Canada goose (Branta canadensis occidentalis Baird). U.S. Department of Agriculture Forest Service, General Technical Report PNW-GTR-591, Pacific Northwest Research Station, Portland, Oregon, USA.Reference A2Kruse KL, compiler. 2014. Central flyway harvest and population survey data book. U.S. Fish and Wildlife Service, Lakewood CO.Reference A3Lynch JJ, Singleton JR. 1964. Winter appraisals of annual productivity in geese and other water birds. Waterfowl Trust Annual Report 15:114-126.Reference A4Marks D, Fischer JB. 2012. Alaska ...