ABSTRACT Uncertainty exists as to how duck harvest regulations influence waterfowl hunter behavio... more ABSTRACT Uncertainty exists as to how duck harvest regulations influence waterfowl hunter behavior. We used the U.S. Fish and Wildlife Service’s Parts Collection Survey to examine how harvest regulations affected behaviors of Central Flyway duck hunters. We stratified hunters into ranked groups based on seasonal harvest and identified three periods (1975–1984, 1988–1993, 2002–2011) that represented different harvest regulations (moderate, restrictive, and liberal, respectively; season length and daily bag limits smallest in restrictive seasons and largest in liberal seasons). We examined variability of seven measures of duck hunter behaviors across the periods: days harvesting ducks, daily harvest, hunter mobility, mallard (Anas platyrhynchos) selectivity, gender selectivity, daily female mallard harvest, and timing of harvest. Hunters reported harvesting ducks on more days, at a higher efficiency, and in slightly more counties during liberal seasons relative to restrictive and moderate seasons. We provide evidence to suggest that future regulation change will affect hunter behaviors.
We analyzed 155,535 samples collected for surveillance of avian influenza viruses (AIVs), in the ... more We analyzed 155,535 samples collected for surveillance of avian influenza viruses (AIVs), in the United States from 2007 to 2009, from migratory waterfowl (ducks, geese, and swans). The goal was to elucidate patterns of prevalence by flyway and functional groups to determine targets for future surveillance. Apparent prevalence of AIV was highest in the Pacific Flyway in 2007-2008 (14.2% and 14.1%, respectively), in the Mississippi Flyway in 2009 (16.8%), and lowest each year in the Atlantic Flyway (range, 7.3%-8.9%). Dabbling ducks had higher apparent prevalence of AIV (12.8%-18.8%) than diving ducks (3.9%-6.0%) or geese and swans (3.6%-3.9%). We observed highest apparent prevalence in hatch-year waterfowl (15.6%-18.9%). We further analyzed 117,738 of the 155,535 samples to test the hypothesis mallard (Anasplatyrhynchos) had highest prevalence of AIV. We compared apparent prevalence and odds ratios for seven species of ducks and one species of goose commonly collected across the Uni...
We analyzed banding and recovery data for Canada geese (Branta canadensis) banded in Nebraska dur... more We analyzed banding and recovery data for Canada geese (Branta canadensis) banded in Nebraska during 1990-2000. Survival rates were lower during 1996-2000 (adult: 0.688, SE = 0.016; juvenile: 0.611, SE = 0.029), than 1990-1995 (adult: 0.727, SE = 0.011; juvenile: 0.639, SE = 0.024). Average juvenile-to-adult ratio from banding data was 0.834 (SD = 0.485), resulting in an annual population growth rate (λ) estimate for 1990-1995 of 0.995 (95% CI = 0.021), and 0.922 (0.018) for 1996-2000. Our recovery analysis suggests that 67% of geese banded in Nebraska are shot in Nebraska. Over 30% of both juvenile and adult recoveries are obtained in December, and geese banded in Lancaster County are recovered in higher numbers during October than geese banded in the Panhandle and Sandhills regions. Sixty to 70% of geese banded in Lan- caster County and the Panhandle region are recovered in their respective region, while less than 20% of geese banded in the Sandhills are recovered in the Sandhills...
... Figure 1. Rainwater Basin sample wetlands located in south-central Nebraska, USA, whereinflue... more ... Figure 1. Rainwater Basin sample wetlands located in south-central Nebraska, USA, whereinfluences of local and landscape level wetland ... Local wetland characteristics.We measured 15 local variables at each wetland to quantify wetland habitat characteristics. ...
ABSTRACT Uncertainty exists as to how duck harvest regulations influence waterfowl hunter behavio... more ABSTRACT Uncertainty exists as to how duck harvest regulations influence waterfowl hunter behavior. We used the U.S. Fish and Wildlife Service’s Parts Collection Survey to examine how harvest regulations affected behaviors of Central Flyway duck hunters. We stratified hunters into ranked groups based on seasonal harvest and identified three periods (1975–1984, 1988–1993, 2002–2011) that represented different harvest regulations (moderate, restrictive, and liberal, respectively; season length and daily bag limits smallest in restrictive seasons and largest in liberal seasons). We examined variability of seven measures of duck hunter behaviors across the periods: days harvesting ducks, daily harvest, hunter mobility, mallard (Anas platyrhynchos) selectivity, gender selectivity, daily female mallard harvest, and timing of harvest. Hunters reported harvesting ducks on more days, at a higher efficiency, and in slightly more counties during liberal seasons relative to restrictive and moderate seasons. We provide evidence to suggest that future regulation change will affect hunter behaviors.
We analyzed 155,535 samples collected for surveillance of avian influenza viruses (AIVs), in the ... more We analyzed 155,535 samples collected for surveillance of avian influenza viruses (AIVs), in the United States from 2007 to 2009, from migratory waterfowl (ducks, geese, and swans). The goal was to elucidate patterns of prevalence by flyway and functional groups to determine targets for future surveillance. Apparent prevalence of AIV was highest in the Pacific Flyway in 2007-2008 (14.2% and 14.1%, respectively), in the Mississippi Flyway in 2009 (16.8%), and lowest each year in the Atlantic Flyway (range, 7.3%-8.9%). Dabbling ducks had higher apparent prevalence of AIV (12.8%-18.8%) than diving ducks (3.9%-6.0%) or geese and swans (3.6%-3.9%). We observed highest apparent prevalence in hatch-year waterfowl (15.6%-18.9%). We further analyzed 117,738 of the 155,535 samples to test the hypothesis mallard (Anasplatyrhynchos) had highest prevalence of AIV. We compared apparent prevalence and odds ratios for seven species of ducks and one species of goose commonly collected across the Uni...
We analyzed banding and recovery data for Canada geese (Branta canadensis) banded in Nebraska dur... more We analyzed banding and recovery data for Canada geese (Branta canadensis) banded in Nebraska during 1990-2000. Survival rates were lower during 1996-2000 (adult: 0.688, SE = 0.016; juvenile: 0.611, SE = 0.029), than 1990-1995 (adult: 0.727, SE = 0.011; juvenile: 0.639, SE = 0.024). Average juvenile-to-adult ratio from banding data was 0.834 (SD = 0.485), resulting in an annual population growth rate (λ) estimate for 1990-1995 of 0.995 (95% CI = 0.021), and 0.922 (0.018) for 1996-2000. Our recovery analysis suggests that 67% of geese banded in Nebraska are shot in Nebraska. Over 30% of both juvenile and adult recoveries are obtained in December, and geese banded in Lancaster County are recovered in higher numbers during October than geese banded in the Panhandle and Sandhills regions. Sixty to 70% of geese banded in Lan- caster County and the Panhandle region are recovered in their respective region, while less than 20% of geese banded in the Sandhills are recovered in the Sandhills...
... Figure 1. Rainwater Basin sample wetlands located in south-central Nebraska, USA, whereinflue... more ... Figure 1. Rainwater Basin sample wetlands located in south-central Nebraska, USA, whereinfluences of local and landscape level wetland ... Local wetland characteristics.We measured 15 local variables at each wetland to quantify wetland habitat characteristics. ...
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