So I’ve seen numerous loons over the years on Lake Vermilion in northern Minnesota–I just never had a good camera with a zoom to get a decent picture of them. Also, they’re wonderful divers (as they’re known in Eurasia), so once they go underwater you literally never know where they’re going to be popping up again.

I’ve managed to get a couple of pictures of a migrating loon on Boomer Lake over the past couple of years.

The common loon goes through two color phases during the year. During the summer the adults have a black-and-white pattern on their back, along with a white breast, and the head and bill are black. During the winter months, the feathers (other than the breast) appear to be more gray in color, and even the bill seems to dull to a gray color.

In terms of size–they’re somewhere between a crow and a goose. They have a long body and short tail, with their feet sticking out behind their tail in flight (which is the opposite of other water birds such as ducks or cormorants). Their legs are further back on the body, making them excellent swimmers and divers, but making it difficult for them to walk on land.

Depending on the season, the common loon can possibly be spotted on some large body of water somewhere within North America. Their breeding range is from Alaska through Canada and then parts of several northern states (such as Minnesota, Wisconsin, Michigan, Maine, and New Hampshire).

The best place to spot them is either on the water or in the air. Since they’re excellent divers, they will be further out on large, crystal clear lakes where they’re hunting small fish. If the water is murky, they may be closer to the shoreline where they’re hunting crustaceans and other shallow water insects.

In terms of migration: (1) loons that breed in western Canada and Alaska can be found migrating to the Pacific coast (anywhere between the Aleutian Islands down to the Baja peninsula of Mexico); (2) loons that breed in the Great Lakes region will migrate down to the Gulf of Mexico or Florida coasts; (3) and the loons that breed in eastern Canada will migrate to the Atlantic coast.

Since their diet consists mainly of fish, loons require basically crystal-clear lakes for hunting. During the summer months in the north they will hunt perch and sunfish, and then other small fish along the coasts in the winter.

If the water isn’t crystal-clear, they will then hunt crustaceans, snails, leeches, and other small insect larvae.

Here are some other facts about the common loon:

Since their bodies are built more for water than land, if a loon lands on a wet highway or parking lot (mistaking them for a river or lake), they can become stranded. Unlike other birds that can do a run to takeoff on land, loons need to be on the water to be able to launch into the air. Therefore they need to land on a large lake or river that gives them the adequate launch space.

Young loons will spend about two years on the coasts before returning to the northern lakes.

They are also ‘late’ breeders, where they don’t start breeding until they’re usually somewhere between four and six years old.

Once they reach their winter coastal grounds, they will molt their wing feathers midwinter, and become flightless until the new wing feathers grow in.

They’re listed as a species of moderate concern in terms of conservation. The main threats include pollution, poisonings (usually unintentional, they may ingest lead fishing sinkers along with gravel stones, and end up dying of lead poisoning), human disruptions near nests, and getting caught in fishing nets.

Reference: https://www.allaboutbirds.org/guide/common_loon