LOONS: GaviiformesRED-THROATED LOON (Gavia stellata): SPECIES ACCOUNTS
COMMON LOON (Gavia immer): SPECIES ACCOUNTS
The anatomy of the loon is specifically geared toward its need to capture fish. Its body is torpedo-shaped, and its neck is thick but longer than the average water bird. There are three toes on each of the two webbed feet, and the legs are toward the back of the body. Though the loons' underparts are totally white, the upperparts are dark gray or black, and the wings have a black-and-white checked pattern on them. All loons have red eyes and long beaks.
Adults range from 2.2 to 13.8 pounds (1 to 6.3 kilograms) and measure about 3 feet (almost 1 meter) long. Males are slightly larger than females.
All species migrate (move region to region, seasonally) to warmer temperatures around the Gulf of Mexico and to the east and west coasts of North America during nonbreeding season. They also migrate to the Mediterranean Sea and coastal China. Alaska is the only region in which all five species can be found.
Loons can be found in inland lakes and tundra ponds. Less often they are seen in large freshwater lakes and rivers during the winter months.
Loons eat mostly medium-sized fish (7 to 8 inches, or 18 to 20 centimeters). Young loons are fed worms, mollusks, and crustaceans such as freshwater shrimp and crayfish.
Loons peer into the water, often with their bills submerged, and dive. Most food is eaten underwater, as loons can remain below the surface for more than a minute. Though most food is caught close to the surface, they may dive as deep as 230 feet (70 meters) if the water is clear enough. Loons eat a lot; a pair can consume 2,000 pounds (910 kilograms) of fish in one breeding season.
BEHAVIOR AND REPRODUCTION
The loon is famous for its vocalizations, which have been described as eerie and haunting. The type of sound—a cry, wail, cackle, or laugh—depends on the species. Vocalizing is usually done on the breeding ground.
Loons are awkward on land because their feet are set so far back on their bodies. In order to fly, they need a good deal of land from which to take off; larger loons need as much as a quarter-mile (400 meters) to get a good start. They are powerful flyers, though, and have been clocked at 60 miles per hour (97 kilometers per hour).
Loons are monogamous (having just one mate) and mate for life, but are quick to replace that mate should it get lost. Both sexes build the nest, and they often return to that same nest every year. Nests are made of wet vegetation on land, or as a floating mat. Usually two eggs are laid, and parents work together to incubate them, or keep them warm. Incubation lasts twenty-four to thirty days. Chicks depend on parents for food but start diving on their own at three days old. In six to eight weeks, they can fly. Adult loons have few predators, but chicks make a fine meal for snapping turtles, eagles, gulls, and crows.
LOONS AND PEOPLE
People are attracted to loons because of the birds' vocalizations. Thousands of tourists flock to the northwoods each year to hear the loons. In this way, loons are beneficial to the tourist industry of these regions. On the flip side, the other human activities involved in these vacations, such as canoeing, are threatening to the birds. When canoes hit the waters of Lake Superior, for example, the loons panic and over-react by abandoning their nests and any eggs in them. Often, they do not return, so the eggs die.
No species of loon is threatened.
Physical characteristics: These loons measure anywhere from 20.8 to 27 inches (53 to 69 centimeters) in length and are the smallest of the loon family. In summer, the red-throated loon's head is gray, the neck is striped, and there is a bright red patch at the front of its neck. In winter, the head and neck are gray on top with a white underside. The bill is black, and the belly is white. The loon's back is always black.
Geographic range: Red-throated loons summer in the tundra and along arctic coastlines. Winters are spent in the Great Lakes region and along the northern coasts of the Atlantic and Pacific Oceans. The birds are also found in the Caspian, Black, and Mediterranean Seas.
Habitat: The red-throated loon is seldom seen far from saltwater. It can be found in estuary (combination of salt water and fresh water) waters at the mouths of rivers. Breeding takes place in freshwater lakes and ponds.
Diet: These birds eat medium-sized fish, preferring marine (salt water) fish to freshwater food.
Behavior and reproduction: This is the only loon that can take off for flight from land because it doesn't require a running start from water. It is also the only loon species to vocalize in pairs, as mated couples do on breeding ponds. The call is a long, low-pitched whistle with individual notes interspersed, and both mates call at the same time.
Although the male chooses the nest site, both parents build the nest from plant matter. Nests are made close to the water's edge because loons have difficulty walking on land. Mating, however, takes place on land. Breeding occurs May through September, and incubation lasts twenty-four to twenty-seven days. Two eggs are usually laid and incubation begins immediately. This means that the first egg is larger, so the first chick is usually the healthier of the two. When food is scarce, the second-born chicks often starve to death.
Red-throated chicks are ready to breed between two and three years of age, and they have been known to live twenty-three years in the wild.
Red-throated loons and people: Inuit legally hunt around 4,600 loons of all species each year for food and skin. Red-throated loon skin is often used to make ceremonial dresses.
Conservation status: Though not threatened, these loons are vulnerable to oil spills and heavy metal pollution. The red-throated loon population is declining, though specific reasons are not known. ∎
Physical characteristics: The common loon stands about 26.0 to 35.8 inches (66 to 91 centimeters) and weighs 5.5 to 13.4 pounds (2.5 to 6.1 kilograms). Underparts are white, upperparts are black with white checks and spots. The head is black, and the neck is black with white striping.
Geographic range: This species breeds throughout Alaska, Canada, northern New England, northern Midwest, and parts of Greenland and Iceland. It winters in the Pacific and Atlantic Oceans.
Habitat: Common loons breed in clear lakes and tundra ponds. The common loon winters mostly on coastal waters within 62 miles (100 kilometers) of shore. It also occasionally winters on inland lakes and rivers.
Diet: These birds eat mainly fish such as perch and bullhead as well as invertebrates such as snails and crayfish. They will eat vegetation when other food is scarce.
Behavior and reproduction: During migration and winter, common loons are found in loose flocks or singly. They prefer large lakes because they require 100 to 650 feet (30 to 200 meters) for takeoff. Common loons are territorial on breeding grounds and will chase off intruders. Their call resembles a yodel, a series of repeated two-note phrases, and is used to defend territory.
Common loons nest farther south than other loons from May to October. They build their nests using vegetation at the edge of a lake. Two eggs are laid and incubated by both parents from twenty-seven to thirty days. Newborns can leave the nest at one day of age and are able to fly at eleven weeks. Chicks and eggs fall prey to gulls, crows, weasels, skunks, raccoons, and snapping turtles. Common loons live for up to thirty years in the wild.
Common loons and people: Human activity upsets the loon, and waterskiiers, boaters, and pets are taking their toll on the loon population. The increased number of houses being built along lakeshores is destroying loon habitat. Loons are also being found with alarmingly high mercury levels in their bodies. The mercury comes from lead fishing tackle as well as pollution.
Conservation status: The common loon is not threatened, though many conservation efforts are underway to keep populations stabilized. ∎
FOR MORE INFORMATION
Klein, Tom. Voice of the Waters: A Day in the Life of a Loon. Minocqua, WI: NorthWord Press, 1999.
Love, Donna. Loons: Diving Birds of the North. Missoula, MT: Mountain Press Publishing Company, 2003.
Silliker, Bill Jr. Just Loons: a Wildlife Watcher's Guide. Minocqua, WI: Willow Creek Press, 2003.
"All About Loons." Northern Wisconsin. http://www.northernwisconsin.com/loons.htm (accessed on May 13, 2004).
"Gavia stellata." Animal Diversity Web. http://animaldiversity.ummz.umich.edu/site/accounts/information/Gavia_stellata.html (accessed May 15, 2004).
Guynup, Sharon. "Loons Sound Alarm on Mercury Contamination." National Geographic. http://news.nationalgeographic.com/news/2003/05/0516_030516_tvloons.html (accessed on May 13, 2004).
Loon Preservation Committee. http://www.loon.org (accessed on July 14, 2004).
Loon Watch. http://www.northland.edu/soei/loonwatch.asp (accessed on July 14, 2004).
"Loons." Alaska Department of Fish and Game. http://www.adfg.state.ak.us/pubs/notebook/bird/loons.php (accessed on May 13, 2004).
Wildlife Conservation Society. http://wcs.org (accessed on July 14, 2004).