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The ospreys returned last month and are incubating three eggs! Assuming the eggs were laid sometime in April, by mid-May we should see the new chicks hatching within five days of each other. For the next 50 days after hatching and before they fledge, the chicks will be dependent on the parents for food. However, sibling rivalry may develop if food resources are limited, and this may result in nest peck order or even the death of one or more of the nest siblings. Last year the osprey pair did raise three young. So let us see how fishing goes this year for the ospreys
Osprey, Pandion haliaetus
also commonly called the fish hawk is
the only species in the family Pandionidae.
Identification
Body color is dark brown above and white below. Head,
white except for a brown stripe from the eye to the back
of the head. The tail has medium-sized, alternating, dark
brown and white bands. The female Osprey had a ring of
brown spots around her neck. The Osprey in flight could
be misidentified as a large gull or even a Bald Eagle.
The Osprey's wings are broader and the wing tips are not
as pointed as a gull's. The Bald Eagle has broader wings
and a larger wingspan. While in flight, large dark patches
at the birds' "wrist" and crooked wings help
distinguish this bird from other species.
Size
56-64 cm (22-25 in) length; 147-183 cm (58-72 in) wingspan.
Though there is overlap between the sexes, females on average
are slightly larger.
Range
The Osprey is one of the world's most widespread birds,
occurring on all continents except Antarctica and many islands.
Originally, it nested widely across North America, but contamination
with the pesticide DDT led to population decrease and range
reduction. The North American Osprey is a migratory bird.
Osprey winter primarily in Latin America and the Caribbean
basin, with concentrations in northern South America.
Reproduction
and nest
The large bulky nest is built by both the
male and female nest and may be reused for many years.
Branches, sticks, twigs, and many unusual materials such
as rope, bones, plastic bags, and other debris, are used
in the nest construction. The nest is built on the top
of large snags, conifers, cliffs, rocky outcrops, bridges,
power-poles and on artificial nesting platforms. New
materials are added each year; so older nests may weigh
hundreds of pounds and be several feet tall. Ospreys
often have back-up nests and may shift back and forth
from year to year. The female lays 3 eggs. The female
incubates the eggs for approximately 33 days. The male
bird may also assist with incubation. The male feeds
the female while she is on the nest. For approximately
40 days, the female remains on or near the nest, caring
for the young. The male brings food to the female during
this time as well, which she feeds to the young. The
adults care for the young for 48-59 days. Usually only
one or two young fledge successfully.
Natural
history
The Osprey is rarely seen far from water,
except during migration. It eats primarily fish but on
occasion has been known to eat snakes, amphibians, and
smaller vertebrates. It generally soars over the water
searching for prey. When the prey is located, it dives
and strikes it with its talons. Instances are known of
Ospreys diving on fish too large for them, getting their
talons stuck in the fish's flesh, and being dragged under
the water and drowned.
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