COMMON LOON, Gavia immer

For inquiries contact Patricia Vittum

The silence of the predawn hours in the northern reaches of the Connecticut River Valley is occasionally shattered by an unearthly tremolo cry, difficult to describe and impossible to forget - almost like a demented person laughing. The caller is a common loon, one of the oldest ("most primitive") birds known.

There are five species of loon, but the one most common in New England is the common loon. This species spends the summers in the northern parts of New England, normally nesting along the shores of the many lakes and ponds of New Hampshire, Maine, and Vermont, as well as the eastern Canadian provinces. However, because there is competition for food, some loons can be seen diving for fish in the River. The birds then migrate to coastal waters (from the Chesapeake Bay to the Gulf of Mexico) for the winter.

Loons are large birds, with wing spans approaching four feet, but they are also relatively heavy birds so the large wings are essential. They are extremely efficient diving birds, and their legs are set well back on the body, which aids in propulsion in the water but makes navigating on land nearly impossible. A loon is vulnerable on land because it can only thrust its chest forward a few inches and drag the legs back underneath the body. As a result, loons leave the water only to nest (very close to the shoreline) and to defecate.

Loons feed on fish and other aquatic life. They overwinter in southern waters, primarily because they must have an expanse of open water (sometimes as much as 400 yards) to get airborne. They return to northern waters in the spring, where the longer days provide ample time for the biologically expensive activities of laying eggs and raising chicks. Loons typically produce two eggs each year. Incubation takes about 28 days, and the parents share the nest duty equally. The average loon pair in New Hampshire fledges one chick each year - heat stress during incubation and predation by large bass and raptorial birds shortly after a chick hatches take their toll.

When the chicks hatch (usually around July 4th in New England), they immediately make their way to the nearby water and leave it only to defecate. The adults now take on the substantial challenge of feeding the babies and themselves - diving for 30 to 50 seconds at a time, catching fish, and feeding them directly to the chicks. During the first week, a chick may crawl on to the back of a parent which is paddling along on the surface. Chicks stay very close to the parents for the first three weeks, and respond immediately to calls warning of birds (or airplanes) flying overhead by scrambling under an adult's wing. The chicks grow very rapidly and are nearly the size of the adults within four to six weeks. They also begin to demonstrate independence, seeking their own food, diving, and exercising their wing muscles. They retain their dull grey back plumage during that time, although the belly turns white.

As winter approaches, the adults congregate with other adults in the region and migrate to more southern waters. Although loons mate for life and normally return to the same territory they occupied the previous year, a pair does not necessarily migrate together, and may not be reunited until the following year. Similarly, juveniles congregate with others in autumn and travel together - leaving before the northern ponds and lakes are covered with ice.

General Reference:

Lan, A. and W. Lynch. Loons. Firefly Books Inc., P.O. Box 1338, Ellicot Station, Buffalo, NY 14205.

Here are some other loon links