Skyrise Nature--Birds on Buildings
Posted on March 28, 2010 at 10:29 AM
Wednesday, Oct 30 at 5:01 AM
The Red-tails nesting on the downtown fire escape are incredibly cool, but they are hardly unique in their ability to ultilize our urban structures for nesting. Birds have been nesting on manmade structures since time immemorial. There are records of Peregrines nesting on European cathedrals dating to the Middle Ages. The people of Strassburg thought it was good luck to have storks nesting on their chimney tops and that lightening would never strike a house so protected. They blew a horn to greet the stork's return each spring.
Habitat loss remains the number one cause of bird declines in North America and more than 25% of the birds that pass through Portland each year are experiencing significant long term declines. However, some birds have found that certain features of our built urban landscape mimic the natural features that they need to survive. The Raptor Cam Red-tails are one example but Portland has many other notable examples as well. Peregrine falcons which naturally nest on cliff ledges will also nest on buildings and bridges--in fact 5% of the know peregrine nests in Oregon occur on Portland area bridges. Vaux Swifts which historically roosted in hollow old growth trees, now use chimneys---that largest known Vaux Swift roost in the world is located at Chapman School in NW Portland. Barns swallows affix their mud nests to this sides of buildings and bridges just as they would do on cliffs. Barn owls, as their name implies utilize barns and other structures for nesting. Osprey can be seen throughout downtown Portland nesting on channel markers, electrical towers and light poles. This list goes on...
Peregrine falcon nesting in Interstate Bridge-By Bob Sallinger
Vaux Swifts at Chapman School
By Dick Forbes
Could our urban buildings do to support the birds passing through Portland? Could we restore nighthawks that once nested in gravel rooftops to our overhead skies by adding gravel to the roofs of riverside buildings on the Lower East Side? Could thousands of acres of grey industrial warehouse rooftops in the Columbia Corridor be converted to meadows for rapidly disappearing meadowlarks and streaked horned larks? Could the tops of our downtown skyscrapers provide a source for insect and a place to rest for migrating songbirds? What can we do on top of our own houses to support our the local wildlife?
If you are interested in learning more about how our buildings could be made more wildlife friendly, you might want to check out a lecture by international ecoroof expert Dusty Gedge this Tuesday at the Oregon Zoo---Go to the "Related Links" Area of the Raptor Cam homepage and click on Skyrise Nature for more information.
Portland Building Ecoroof by Bob Sallinger