Winter Waterfowl

Since December 1988, the Lloyd Center has surveyed wintering waterfowl in estuaries from the Sakonnet River in Rhode Island to Apponagansett Bay in Dartmouth, Massachusetts.

In what started as an effort to determine the importance of Allens Pond Estuary to the American black duck, a migratory dabbling duck relying exclusively on estuaries for its intertidal food source, the waterfowl survey has become both an enjoyable opportunity for long-time volunteers, and a crucial inventory of a premier bird assemblage in southeastern New England. Once bodies of freshwater freeze further north, many duck species breeding in forested freshwater wetlands depart south to our estuaries which rarely ice over. But estuaries do partially freeze, and tide and weather conditions can influence survey outcomes, so both an early December and a late January or early February survey are conducted.  On the two Sundays, volunteers venture out to survey, then stop by the Lloyd Center for Mark Mello’s famous linguica stew, and provide us with their count results.

A large diversity of wintering ducks features divers such as bufflehead, and red-breasted and hooded merganser, each of which enjoy more secluded portions of estuaries. Closer to the sea at the mouths of systems one commonly finds sea ducks such as scoters , scaup,  eiders, goldeneye, and long-tailed duck. When large salt ponds aren’t frozen, ruddy ducks are yet another of many species one may see in addition to the abundant black duck, gadwall, American widgeon, green-winged teal, increasing numbers of migratory Canada geese, and congregations of the resident mute swan. Loons and grebes also mix amongst the ducks, geese, and swans, adding to the diversity.  

Winter Waterfowl Update - February 2008

On Sunday February 3, 2008, Lloyd Center staff scientists and volunteer surveyors completed the 2nd count for this season’s annual winter waterfowl survey, from the Sakonnet River in Rhode Island to Apponagansett Bay in Dartmouth.

This year’s total of 7,073 birds in our estuaries and coastal ponds surpasses the December total of 6,208. This is the usual trend, with some interesting contrasts in migratory behavior between more common species that results in the higher mid-winter numbers.

Common goldeneye and Canada goose both tend to increase in numbers as winter progresses, but their breeding ranges correspond to differing migration schedules and routes. Goldeneye start migrating later and fly in from wetlands as far as Alaska, such that arrival to our estuaries occurs later in the season. For Canada geese, many late autumn birds are resident year-round and have simply ‘dispersed’ from nearby inland areas to our estuaries when ice forms. From that time onward, numbers increase gradually as true migrants from the north add to our in-state population.

When we compare this latest survey (7,073 birds) to last year’s same mid-winter count held on January 28, 2007 (5,048 birds) in terms of overall numbers, we saw significantly less ice cover this year, which helped boost total numbers.

Regarding changes in species abundance, more than half of the 21 species showed at least a slight surge from a year ago. The always common bufflehead showed the highest increase of all waterfowl. Hooded mergansers, a less abundant diving duck, had higher numbers than usual. The area with highest concentration was the east branch of the Westport River below Hix Bridge (738 birds), where Canada geese and bufflehead were most numerous. While no rare birds were seen, the pair of white winged scoters (the largest member of the scoter family) on the Slocums River is notable, since only 22 records of the species exist for this survey. Surf scoters are the most commonly seen member of the family, and often visible in high numbers in Padanaram Harbor.

In progress is a summation of all winter waterfowl data from 1988-2007; this more detailed report to be completed in the coming months.