Habitat 2000 / Learning About Wildlife
The return of the osprey to Canada's rivers and lakes is
as remarkable as the rebirth of the mythical phoenix from
its own ashes. Once threatened with extinction due to the
harmful effects of pesticides on its eggs, the osprey has
made a phenomenal comeback since DDT was banned in North America
in the early 1970s. But now this magnificent fish-hawk faces
another challenge: the loss of nesting sites in tall trees
and snags along shallow bodies of water because of human development.
To compensate for this habitat shortage, schools, Scouts,
and community groups from coast to coast are providing artificial
nesting platforms -- with remarkable success. There are various
ways to erect nesting structures, depending on the terrain.
On hard terrain, for example, platforms are usually mounted
on single poles, which are bolted to rock. Quadrupods -- four
poles lashed together -- are used to support platforms in
wetlands with muddy bottoms.
The scale of these projects requires that you tap into the
resources of your community. Here's how to erect a single-pole
structure on soft terrain:
- Remember, location is everything. Since ospreys feed almost
exclusively on fish, nesting sites should be no more that
3 km from shallow wetlands; 50 m is ideal. Choose open areas,
at least 300 m apart and 100 m away from human activity.
- Before you begin, contact your ministry of natural resources
to see if you need a permit to build platforms along rivers
or lakes in your region.
- Find a solid utility pole, 7 to 9 m long and 15 or 20
cm in diameter. Your local hydro or telephone company may
give away used poles.
- Secure a sturdy 1.2 m x 1.2 m shipping pallet (preferably
with a 25-cm-high fence attached) to one end of the pole,
using lag bolts and metal braces. Wire a few sticks to the
platform to make it more appealing.
- Drill a hole, 1.5 to 2 m deep, in the earth with a power
auger. Set the pole in the hole, then secure it with cement.
- Attach guy wires to the pole if necessary to make it more
stable.
- Nail a sheet-metal predator guard around the base of the
pole to protect osprey nestlings from raccoons.
- Inspect the structure at lease once a year. Remove a layer
of sticks if nesting material gets deeper that 50 cm.
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