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The Common Loon
Common Loon (Gavia immer)
Common Loon Characteristics
• Size = 28-36 inches
• Male/Female = Large,
checkerboard back
with white necklace,
black head, red eye,
long pointed black
bill.
• (gray in fall and
winter).
Common Loon Characteristics
• Eggs = 2 olive brown.
• Incubation = 26-31 days.
• Migration = complete, to
golf coast.
• Food = fish, aquatic insects.
Common Loon Territory
• Territory is needed for
mating, nesting, and
feeding.
• Summer Territory Size =
60-200 acres
• Winter Territory Size = 1020 acres
• Place on land, island,
peninsula- at water’s edge.
• Size = About 2 feet in
diameter.
• Materials = reeds, grasses,
water plants, moss.
A loon takes its newly hatched chick
for a ride on its back
• The chick shown here is only a
couple of days old and will ride
intermittently on the adult for
the first 10 days.
• They do this for two main
reasons:
1) to conserve energy for
growth, and
2) for protection from
predators, such as snapping
turtles and great black-backed
gulls.
• Adults will also hide their
young chicks under their wings
or in vegetation along the lake
shore.
A loon preparing for departure
• Unlike other aquatic birds loons
cannot "spring" from the water.
• As a matter of fact, they need a
large runway and a bit of wind,
just like an airplane!
• Loons are so heavy that they
need to attain a high speed
against the wind to get enough
lift to become airborne.
Adult incubating eggs
• Loons usually lay 2 eggs and
incubate them for 29 days.
• Unlike other waterfowl, loons
share incubation duties and the
male will sit on the nest just as
often as the female.
• Loons prefer to nest in quiet,
secluded areas protected from
wind. Most often they will
choose an island, which also
protects them from terrestrial
predators.
• Many different materials are
used in building a nest. Usually
it consists of items found in the
immediate vicinity of their
nesting site, such as grass,
sedge, moss and mud.
• Penguin Dance
• Loons often have to defend
their territories from intruders,
such as humans or other loons.
• Vocalizations are one way to
ward off intruders but often a
visual display is necessary.
• When loons "penguin dance"
they run on the water while
extending their breasts out to
make them seem much larger to
the unwelcome visitor.
• This is the most aggressive
display that loons make and can
be accompanied by a hostile
altercation between loons,
which occasionally results in
death from a bill stab.
Songs of the Loon
• Anyone who has spent time in the northern
woods has undoubtedly heard the haunting call
of the Common Loon.
• There are four basic calls, which are heard
mostly in the spring and summer.
• Each call has a different meaning.
Hoot
• The hoot call is not as intense or as loud as the
other calls.
• It is used to keep in contact with mates, chicks
and social groups residing or visiting the same
lake.
Tremolo
– The tremolo has been described as "insane laughter";
it is 8 to 10 notes voiced rapidly which vary in
frequency and intensity.
– This alarm call usually indicates agitation or fear,
often caused by disturbance from people, a predator
or even another loon.
– This is also the only call that loons make in flight.
Wail
• The wail is most frequently given in the evening
or at night, and can be heard for many miles.
• This haunting call is not an alarm call but is used
to keep in contact with other loons on the same
lake and surrounding lakes.
Yodel
• The yodel is only made by male loons.
• This call is used to advertise and defend their
territory, especially during incubation and early
chick-rearing.
• If you are watching loons and they make this call
or a tremolo, it usually means that you are too
close and are disturbing the loons. If that
happens, you should leave their territory and
give them their space.
• The common loon (Gavia immer) is anything but common. This redeyed black and white water-bird with a daggerlike beak is most closely
related to primitive birds and its soliloquy of cries can sound eerily
prehistoric.
• Loons are reclusive and solitary. Pairs prefer a secluded lake or estuary
that can support a diet of small fish and crustaceans.
• They are excellent swimmers and can dive for minutes. Larger than
most ducks, loons are awkward and most vulnerable on land.
• Their thrashing water take-offs are lengthy and far from graceful.
• Silent in winter, the loon repertoire of calls haunt the night with
strange laughter-like calls, falsetto wails and strange yodelling.
• Sighting and hearing a
loon is still considered a
treat to any bird lover.