Osprey
Pandion haliaetus
While many of Colorado’s bald eagles are flying back to
their summer locations, a summer resident of Colorado is making their reappearance. The ospreys are back!!
This awesome bird of prey is a fish eating hawk, and
seeing one dive into a body of water to catch its prey is a spectacular sight!
Ospreys are a kind of hawk, and have dark wings and tails
with white heads, legs and underbelly. They also have unusual feet for hawks, with
a toe that can rotate to be opposable so that they can get a better grip on
their wiggly prey; fish!
Osprey is the only hawk that’s diet consists of 99% fish,
and will rarely eat anything else. They have sharp spines on their feet to help them
keep hold of their prey, and have a very high success
LIFE CYCLE
Osprey will build their nests wherever they can, and have to
qualms with building their nests on manmade structures. Manmade nesting
platforms have been a huge aid in osprey recovery since DDT had drastically
reduced their numbers in the 1950’s.
Osprey build large stick and sod nests lined with grasses
and bark. The male is often the one who collects the nest material, while the
female puts the nest together. Nests in the ospreys first season start out
relatively small, around 2.5 feet in diameter, and as they add on each year nests
can become as large as 3-6 feet in diameter and 10-13 feet deep!
Osprey typically mate for life. When a male osprey reaches
the age of three, he will return to the summer breeding area that he was born
in, and he will find a nesting site of his own.
In the mating season, usually around May, the male will
preform a “Sky-dance” for the female, usually carrying fish or nesting
material. He will hover and swoop as high as 600 feet or more over the nesting
site.
The female responds to the male’s dance by landing at the
nesting site and eating the fish that the male supplied her with. Once they are
bonded, they will return to the same nesting site together for the rest of
their lives.
Osprey usually lay three eggs, which do not all hatch at
once. Hatching is staggered, with the older chicks getting most of the food. If
there is enough food to go around, all the chicks are fed. If there is not
enough food, the youngest usually starve.
The female stays with the young to incubate the eggs and
feed the chicks, while the male hunts and provides the female and chicks with
food.
FUN FACTS
- Osprey can migrate great distances in search of prey. In its lifetime, an osprey may travel as far as 1600,000 miles!
- Osprey can completely submerge themselves when diving for prey and still fly afterwards! This is unlike other fish eating birds of prey, which can only pluck fish from the surface.
- Osprey are very well adapted for fishing. They have a third eyelid which they can use like goggles when diving for fish, and they can even close their nares, or nostrils, to prevent water from getting up their nose!
- Osprey are smart..when flying with fish, they will line up the fish head first to reduce wind resistance!
- The osprey is one of the most widespread birds of prey! They can be found in every continent except for Antarctica.
- Canada is home to one third of the world’s osprey population
- Osprey have a wingspan of 1.6 meters
- An osprey’s main predators are raccoons (they eat the eggs) and great horned owls, which will eat both the chicks and sometimes even the adults.
- Osprey can live up to 30 years on average!
- Fossils found in Southern California suggests that osprey have been around since the mid-Miocene Era, around 15 to 11 million years ago!
INDICATOR SPECIES
Osprey are at the top of their food chain, and because of
this can indicate the overall health of an ecosystem. If there are chemicals polluting an
ecosystem, animals that are lower in the food chain can digest small amounts,
and this amount will accumulate the higher we go on the food chain, so that
animals on the top will feel the greatest effect. A healthy osprey population means a healthy ecosystem!
Boulder County Osprey Cam:
Cornell Lab of Ornithology Osprey cam:
SOURCES:
Cornell Lab of Ornithology
Friends of the Osprey
http://www.friendsoftheosprey.org/osprey.html
National Geographic
Smithsonian
The Peregrine Fund
