Horned Grebes

December 2015

As I scan the open waters of Lake Champlain with a pair of binoculars near Button Bay in Ferrisburgh, I think I spy a thin, long-necked, duck-like silhouette far from shore, rocking on the waves. I barely register the white neck with dark head and body before it is gone beneath the water. Careful observation reveals that a few of them are out there, constantly appearing and disappearing. These are horned grebes, common winter visitors on lay-over en route to the Atlantic Ocean.

Every winter horned grebes appear on our lake. Bird populations are recorded during annual Christmas Bird Counts, one-day attempts by volunteers to count all the birds in a pre-defined circle of 15-miles diameter at some point between late December and early January. There are four regular Christmas Bird Counts that include extensive areas of open water on Lake Champlain. They are centered on Ferrisburgh, Burlington, Plattsburgh, and Knight Island in the Inland Sea. In 17 of the last 25 years there have been more than 100 horned grebes reported during the four counts. The lowest total during that period was 14 in 2008 and the highest total was 404 in 1988. Numbers will be influenced by weather on the day of the count, the extent of ice coverage, and when in the migration period the count happens to fall.

In breeding plumage, male horned grebes sport yellow tufts of feathers extending back from their red eyes which they spread in courtship. Their body is russet brown. However, breeding plumage is reserved for their nesting grounds in the western Canadian Provinces north to Alaska. On Lake Champlain we only catch the black and white winter plumage.

Grebes are members of the family Podicipedidae, which roughly means “rump footed” in Latin, an allusion to the location of the feet near the rear of the body. The family contains 22 species. Grebes are excellent divers, staying underwater for up to three minutes at a time. Walking on land is much more difficult than swimming for them because their feet are in such a posterior position. If a grebe accidentally mistakes a road for a river or a parking lot for a lake, they are unable to take off, as they cannot generate sufficient forward momentum.

Grebe feet are distinctive apart from their location on the body, as they act like wings once the bird dives. The large feet have broad lobes on their toes and small webs connecting the front three toes. When grebes dive the feet arc perpendicular to the plane of motion, like a boat propeller. The propeller-like motion generates lift and is thought to increase swimming speed and energy efficiency compared to the swimming motion of ducks. Ducks moves their feet parallel to the line of motion, like a canoe paddle. Energetically, the grebe’s style is more similar to that of puffins or penguins which use their actual wings to fly under water with their feet acting as rudders.

Loons also use their feet to propel themselves when diving. For this reason, they were once classified in the same family as grebes. Molecular studies however suggest that foot-propelled diving is an example of convergent evolution, when similar features evolve in different lineages like the wings of bats and birds.

The feathers of grebes start out at right angles from skin. By pressing their feathers against the skin, grebes can increase or decrease the amount of air they trap, and adjust their buoyancy. Sometimes they will appear to be swimming very low in the water with only head and neck exposed.

While horned grebes are by far the most common representatives of their family on Lake Champlain during the winter, two other species are found with some regularity. Red-necked grebes, like the horned grebe stop by on their way to the ocean from breeding grounds they share with horned grebes. Pied-billed grebes breed in small numbers around Lake Champlain and occasionally linger into the winter.

Red-necked grebes are larger with longer bills and more gray in the cheek and neck compared to horned grebes. The most red-necked grebes ever observed on the Champlain Christmas Bird Counts was 11 in 1999 when six were found in Burlington and five in Ferrisburgh. There are numerous years when none are located.

Pied-billed grebes are much smaller and thicker with stubby bills. Their body is dark overall. Pied means having two colors and for this species refers to the dark strip that separates their otherwise silvery bill. The stubby bill reflects that they feed more on crustaceans and insects than the fish that sustain horned and red-necked grebes. Pied-billed grebes have only put in an appearance in about half of the last twenty-five years of Champlain Christmas Counts, with a maximum of five birds in 2006, three in Plattsburgh and two in the Knight Island circle.

Grebes are not birds that a casual lake user will stumble upon. They are usually far from shore and require a search with binoculars or spotting scope. Horned grebes, the most numerous, are only here during the colder months of the year, and they will move to the ocean once the ice sheet grows. However, they are not particularly hard to find if one is willing to put in the effort. 

Lake Look is a monthly natural history column produced by the Lake Champlain Committee (LCC). Formed in 1963, LCC is the only bi-state organization solely dedicated to protecting Lake Champlain’s health and accessibility. LCC uses science-based advocacy, education, and collaborative action to protect and restore water quality, safeguard natural habitats, foster stewardship, and ensure recreational access.

Get involved by joining LCC using our website secure form (at www.lakechamplaincommittee.org), or mail your contribution (Lake Champlain Committee, 208 Flynn Avenue - BLDG 3 - STUDIO 3-F, Burlington, VT 05401), or contact us at (802) 658-1414, or lcc@ lakechamplaincommittee.org for more information.