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WESTERN GREBE (Aechmophorus occidentalis)
By Lewis Young
 The
Western Grebe is a striking black and white bird with a
long slim neck and a long bill. The largest of our
grebes with a length of 25 inches, a wingspan of 24
inches, and weighing just over 3 pounds, they have a
long greenish-yellow sharp-pointed bill, and black (or
dark gray) and white plumage. The dark plumage is found
on the top of the head, back of the neck, and the upper
body. The white is found on the chin, front of the neck
and the underside of the body. At close range, the red
eye may be seen. Their tail feathers are very small and
hidden among other body feathers. A gregarious, colonial
nesting species, they are infrequently seen on land or
in flight. Males and females are generally
indistinguishable.
The Western Grebe is one of seven species of grebes in
North America and easily separated from other grebes,
except the Clark’s Grebe, which is also occasionally
found in our area. Differences in bill color and the
pattern of white on the face allow the two species to be
differentiated. The Clark’s has a bright yellow or
orange bill and white surrounding the eye, while the
Western has a yellowish green bill and dark surrounding
the eye.
 Western
Grebes are famous for their elaborate courtship displays
with different phases at different stages of breeding.
Perhaps most recognized is the ballet-like rushing
display in which 2 birds in unison rear to an upright
posture with necks kinked and wings swept back, race
across the lake surface with a great pattering of feet,
then dive underwater. Their nest is a floating heap of
plant material anchored to standing vegetation in a
shallow water marsh. Their 2-4 bluish-white eggs become
brown-stained over time and both sexes incubate the eggs
for about 24 days. Hatching is not synchronized, so the
last egg may be abandoned in the nest. Chicks can swim
and dive from birth and often ride upon parents’ backs
for shelter, protection, and brooding. Adults may even
dive with chicks on their backs. Chicks have bare yellow
spots on their heads that become vivid red when begging
for food or alarmed. They take their first flight in
about 10 weeks.
The diet of the Western Grebe is mostly fish, although
they are also known to eat crustaceans, insects, worms,
and salamanders. Most foraging occurs at or near the
water’s surface, but they can dive to 90 feet. They also
eat large numbers of their own feathers, primarily from
their flanks and belly. This may protect their stomachs
from puncture by indigestible parts of the prey they eat
and the feathers also provide the base material for
regurgitated pellets of undigested items such as fish
bones.
 Western
Grebes summer mainly on freshwater lakes with large
areas of open water and marsh vegetation throughout much
of the western US and southern Canada. They winter on
sheltered bays or estuaries along the Pacific coast, and
inland on large freshwater lakes (rarely rivers)
primarily in the southwestern US and parts of Mexico.
Western Grebes may be found in the Flathead Valley and
surrounding area both summer and winter. Western Montana
hosts overwintering birds on large lakes like Flathead
Lake and Koocanusa Reservoir when they are ice free.
Flocks of over 50 birds have been observed on Koocanusa
Reservoir on the Eureka Christmas Bird Count and flocks
of over 200 birds during fall migration. Migration
between summer and winter ranges is believed to occur at
night in flocks.
 In
the early 1900’s, tens of thousands of Western Grebes
were killed for their “fur,” which was used to make hats
and coats. Natural predators include large fishes such
as bass and pike, turtles, herons, gulls, raccoons, and
mink. Western Grebes are susceptible to a variety of
toxins and human related influences. PCB’s and
organoclorine pesticides cause eggshell breakage and
nesting failure. Ingestion of lead fishing weights and
lures cause lead poisoning. Nesting and feeding habitat
is often altered by human activities such as development
on lakes, vegetation clearing, boating, and alteration
of water levels.
Western Grebes contribute to the wonderful birdlife
diversity on our lakes, and should you ever be fortunate
enough to observe their mating “dance,” you will be
enthralled and have a great memory to associate with
sightings at other times of the year.
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