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Patuxent Science Meeting 2006 Poster Abstract

Comparing mallard population indexes in the Mississippi Alluvial Valley

between January 1988-1990 and 2005-2006

Reinecke KJ, Pearse A, Kaminski R

Since 1995, mallard populations have increased and harvest management has provided liberal

hunting opportunities. New refuges have been acquired in the Mississippi Alluvial Valley (MAV)

and private landowners have increased habitat management. Overall perceptions about mallard

populations should be positive. Nevertheless, controversy has increased regarding the

abundance and distribution of mallards in the MAV. Perceptions are that mallard winter

populations have decreased. We began addressing this issue by: (1) improving the design of a

sample-based mallard winter survey; (2) completing surveys of the MAV to estimate mallard

population indexes in January 2005 and 2006; and (3) comparing the January 2005-2006

indexes to estimates from similar surveys in the late 1980s. Mallard population indexes were

989,061 (SE = 72,316) during 3-25 January 2005 and 990,007 (97,271) during 2-20 January

2006, whereas the mean of indexes from 3 similar surveys in January 1988-1990 was

1,424,560. The mean of indexes from January 2005 and 2006 decreased 31% from the mean of

the late 1980s, although mid-continent fall flight indexes of mallards in autumns 2004 and 2005

were greater ( 9.3-9.4 million) than those during autumns 1987-1989 ( 7.1-8.0 million). January

2005 and 2006 population indexes decreased in Louisiana (-35%), Mississippi (-73%), and

Arkansas (-22%), but increased in Missouri (+168%). The percentages of mallards observed on

private lands ranged from 81% in January 2006 to 93% in January 2005. We concluded: (1)

January 2005-2006 mallard population indexes decreased compared to the late 1980s; (2)

mallards were not concentrated on public lands and unavailable to hunters in January 2005-

2006; and (3) USGS scientists should work with state waterfowl biologists to continue the

Friday, September 22, 2006

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