On a chilly December Sunday, volunteers for the Lloyd Center counted 8,494 birds for the Center’s annual Winter Waterfowl Survey.

“People often think in winter not a whole lot’s going on,” Lloyd Center Research Associate Jamie Bogart said. “Well, if you look at the coast, there’s all kinds of waterfowl.”

The Lloyd Center began the survey in 1988 with a focus on the American black duck and a goal of determining how important the habitats were to the species. From there, the survey expanded to 21 locations in Dartmouth, Westport, Tiverton, and Little Compton. Locations include marshes, salt ponds, rivers, and freshwater ponds.

The survey takes place over two Sundays, usually the first Sunday in December and the last Sunday in January. This gives researchers data from the late fall and mid-winter. Researchers also record how much ice is covering bodies of water.

Estuaries — places where rivers and streams meet the sea — are a vital habitat for freshwater ducks and geese during the winter when many freshwater areas freeze over. Salt water and areas where water is in motion, like rivers and streams, freeze at lower temperatures than freshwater ponds, which provides a perfect place for fowl to spend the winter.

The survey provides researchers not only with information about the diversity and population size of waterfowl, but also about the health of the estuaries themselves. Unhealthy bodies of water provide less nutrition for fowl, and will therefore have fewer birds.

This year, the most dominant species by far were Canada geese, who composed 88 percent of all the birds counted.

“Right now, as development of the landscape, like human use and building along the coastline have increased, Canada geese have skyrocketed,” Bogart said. “They are the most abundant waterfowl species we see.”

Bogart said that the geese are a species that has benefited greatly from human activity because they like to feed in fields, like those used for agriculture. People also like to feed them in local parks, which can harm the birds because foods like white bread are bad for them.

Mallards, the ducks with the green heads, have also expanded in population and have outcompeted the American Black Duck because the mallards are able to survive in environments that are affected by human use.

The five most common species counted, called the dominant species, were the Canadian goose, American black duck, bufflehead duck, mallard, and red-breasted merganser.

The next five most common species, called sub-dominant, were the scaup, mute swan, ruddy duck, common goldeneye duck, and canvasback duck.

In December, the count had to be delayed by a week due to bad weather, so there was more ice coverage at the time of the survey, and more birds. This year’s survey counted 2,589 more birds than last year’s survey.

The second count will take place on January 27. For more information about the Lloyd Center’s research on winter waterfowl and other subjects, go to www.lloydcenter.org.