The Great Northern Loon is one of the five loon species. Its
closest relative is the other large black-headed species, the Yellow-billed
Loon or White-billed Diver.
Adults can range from 61 to 100 cm (24–40 inches) in length
with a 122–152 cm (4–5-foot) wingspan, slightly smaller than the similar Yellow-billed
Loon (or "White-billed Diver"). The weight can vary from 1.6 to 8 kg
(3.6 to 17.6 lbs). On average a Great Northern Loon is about 81 cm (32 inches)
long, has a wingspan of 136 cm (54 inches), and weighs about 4.1 kg (9 lbs).
Breeding adults have a black head, white underparts, and a
checkered black-and-white mantle. Non-breeding plumage is brownish, with the
chin and foreneck white. The bill is black-blue and held horizontally. The bill
colour and angle distinguish this species from the similar Yellow-billed Loon.
Bone structure contains a number of solid bones (unlike
normally hollow avian bones), which add weight but help in diving.
Distribution and habitat
The Great Northern Loon breeds in North America, Greenland , Iceland ,
and Great Britain .
This species winters on sea coasts or on large lakes of south Europe and the United States , and south to northwestern areas
of Africa .
Behaviour
Chicks will ride on their parents' backs
This species, like all divers, is a specialist fish-eater,
catching its prey underwater, diving as deep as 60 m (200 ft). Freshwater diets
consist of pike, perch, sunfish, trout, and bass; salt-water diets consist of rock
fish, flounder, sea trout, and herring.
The bird needs a long distance to gain momentum for
take-off, and is ungainly on landing. Its clumsiness on land is due to the legs
being positioned at the rear of the body: this is ideal for diving but not
well-suited for walking. When the birds land on water, they skim along on their
bellies to slow down, rather than on their feet, as these are set too far back.
The loon swims gracefully on the surface, dives as well as any flying bird, and
flies competently for hundreds of kilometers in migration. It flies with its
neck outstretched, usually calling a particular tremolo that can be used to
identify a flying loon. Its flying speed is about 120 km/h (75 mph) during
migration. Its call has been alternately called "haunting,"
"beautiful," "thrilling," "mystical", and
"enchanting."
Great Northern Loon nests are usually placed on islands,
where ground-based predators cannot normally access them. However, eggs and
nestlings have been taken by gulls, raccoons, skunks, minks, foxes, snapping
turtles, and large fish. Adults are not regularly preyed upon, but have been
taken by sea otters (when wintering) and Bald Eagles. Ospreys have been
observed harassing divers, more likely out of kleptoparasitism than predation.
When approached by a predator of either
its nest or itself, divers sometimes attack the predator by rushing at it and
attempting to impale it through the abdomen or the back of the head or neck.
Breeding
The female lays 1 to 3 eggs on a hollowed-out mound of dirt
and vegetation very close to water. Both parents build the nest, sit on the egg
or eggs, and feed the young.
Relationship with humans
These birds have disappeared from some lakes in eastern North America due to the effects of acid rain and pollution,
as well as lead poisoning from fishing sinkers and mercury contamination from
industrial waste. Artificial floating nesting platforms have been provided for
loons in some lakes to reduce the impact of changing water levels due to dams
and other human activities.
This diver is well known in Canada ,
appearing on the one-dollar "loonie" coin and the previous series of $20
bill, and is the provincial bird of Ontario .
Also, it is the state bird of Minnesota .
The voice and appearance of the Great Northern Loon has made
it prominent in several Native American tales. These include a story of a loon
which created the world in a Chippewa story; a Micmac saga describes Kwee-moo,
the loon who was a special messenger of Glooscap (Glu-skap), the tribal hero;
native tribes of British Columbia believed that an excess of calls from this bird
predicted rain, and even brought it; and the tale of the loon's necklace was
handed down in many versions among Pacific Coast peoples. Folk names include
big loon, black-billed loon, call-up-a-storm, ember-goose,
We often see Loons on our workshops and have experience anticipating
their movement to offer you the best opportunity to photograph them in the
environment.
Please check out our workshops and come photograph some
Loons. www.northof49photography.com
No comments:
Post a Comment