AUGUSTA, Maine – Each winter, ducks, geese and swans are counted annually along Maine's coast during the Midwinter Waterfowl Survey. U.S. Fish and Wildlife Service pilot John Bidwell, accompanied by Michael Schummer, wildlife biologist with the Maine Department of Inland Fisheries and Wildlife, flew the survey and counted waterfowl from January 3- 17 of this past year. In 2007, a total of 68,860 birds was a substantial decrease from last year's count of 82,365.
The Midwinter Waterfowl Survey is conducted at the same time each winter in each state in the Atlantic Flyway, from Maine to Florida. Overall status of wintering waterfowl populations are determined when Maine's count is pooled with other states' numbers. Therefore, high numbers for some species counted in Maine this January may be offset by lower counts in states farther south, or vice versa. Based on these assumptions and imprecision of the survey, Midwinter Waterfowl Survey data are best used to assess longer trends (5 to 10-year count averages) rather than to determine actual year-to-year changes in waterfowl abundance.
Most notable was a decrease in the number of Common Eiders (18,041), down 16,000 from 2006 (34,041) and only 801 greater than the last low count in 2004 (17,240). Black duck numbers were greater during 2007 (20,303) than in 2006 (16,631), slightly higher than the 10-year average of 18,419. Buffleheads (8,629) posted the largest number counted since 1998 (9,270) and were substantially above the 10-year average of 5,447. The number of Canada geese counted this year (3,961) was comparable to the 2006 (3,338) and 2005 counts (3,489).
An increase in the number black ducks and buffleheads this year was likely a result of a relatively mild fall and winter. Mild conditions can also mean that birds more adapted to cold environments, such as goldeneyes, are able to winter farther north than Maine. This year, during the count period, mallards and goldeneyes seemed abnormally abundant on inland lakes and rivers that continued to remain unseasonably ice-free. As the Maine Midwinter Waterfowl Survey only covers marine waters, it is likely that lower count numbers were a result of birds remaining in open freshwater lakes and rivers that normally are iced over. Weather was not extreme enough to cause birds to move farther down the Atlantic Coast. In a normal year it takes 30 hours of flying to count waterfowl on the coast of Maine. Reduced ice coverage equates to more areas that waterfowl can disperse, and this year 42.5 hours was required to cover the same survey area. For example, in 2006 Merrymeeting Bay was nearly entirely frozen. This year, it took an hour to survey this area that was nearly entirely ice-free. We counted nearly 1,500 ducks and geese where in 2006 we only saw ice.
Waterfowl counted this year (2006 numbers in parentheses) include: black ducks 20,303 (16,631), mallards 2,960 (4,025), scaup, 72 (73), goldeneyes 4,408 (5,982), buffleheads 8,629 (6,770), mergansers 5,238 (4,114), long-tailed ducks 3,272 (2,865), scoters 1,809 (4,480), eiders 18,041 (34,041), and Canada geese 3,961 (3,338). Other species observed but found in relatively low numbers include: ruddy duck 134, northern pintail 1, and ring-necked ducks 1.