Apr. 20, 12:48 EDT
Peregrines flock to Burlington lift bridge
Sighting of second nesting pair in area signals recovery of the 'kings of the sky' in southern Ontario
SUSAN LAMEY
Special to The Hamilton Spectator
A peregrine falcon sits on a high ledge of the Burlington lift bridge
Picture below.
Photos by John Rennison, the Hamilton Spectator
A peregrine falcon sits on a high ledge of the Burlington lift bridge near its nest, circled above. There are three or four eggs in the nest, which is protected under the Endangered Species Protection Act.
A second pair of peregrine falcons seen soaring through the skies over Hamilton and Burlington for the past 26 months has chosen the Burlington lift bridge as its nesting site.
"It's all about location," says Mark Nash, executive director of the Canadian Peregrine Foundation who has been monitoring these very visible "kings of the sky."
Nash isn't certain the pair nesting on the bridge is the same that has been been sighted in the area, but it is very unusual to have a brand new pair show up.
The Burlington birds are one of only eight nesting pairs in southern Ontario. Others are in Ottawa, London, Mississauga, Toronto and St. Catharines, plus the pair that have nested at Hamilton's downtown Sheraton since 1995.
"It is very, very good news for the recovery of the peregrines in southern Ontario," said Nash.
Nash says he has been trying to identify the birds since October and has been successful with the male. The leg band says the bird's name is Surge. He comes from a 2002 nest in Etobicoke. The female has a black over green band on one leg and a purple band on the other. The band colours suggest she comes from either Pennsylvania or Ohio. But an official identification is impossible until the numbers on her leg band can been seen.
An excited Nash says Surge is one of only two Canadian falcons in southern Ontario. Very few Ontario birds tend to return to Ontario to nest, with most of the southern Ontario falcons ending up in Pennsylvania, Ohio, New York or Wisconsin. The peregrines in Canada normally come from the United States.
Peregrine falcons are cliff dwellers and the bridge is a perfect spot for a nest.
The birds choose high ledges with good sight lines for prey and to keep an eye on predators. The peregrines will scratch out a nest bowl on ledges that have a gravelly consistency to allow water to drain away from the eggs. Embryos can drown if there is too much water, and heat loss caused by the eggs sitting in water can't be compensated by the parents roosting on them.
The height of the nests allows the falcons to use the winds and thermals to reach altitudes that allow them to dive at speeds of 300 kilometres per hour, catching and killing their prey in the air.
"Peregrines dine exclusively on birds and the nearby wetlands provide an abundance of birds."
The nest material atop the bridge isn't ideal, but Nash says the nest is contained which will allow the eggs to incubate properly.
Nash would have liked to line the nest with pea gravel which doesn't damage or crack the eggs when the birds turn them during incubation. His plan to put a nesting tray on the bridge will have to wait for the fall.
There are three or four eggs in the nest which have made it off limits and protected under the Endangered Species Protection Act.
Peregrines are creatures of habit and very territorial and the "Burlington pair" should return to the bridge next year even if this year's hatch is unsuccessful.
"It is normal for the first hatch to fail."
The sighting of this second nesting pair has demonstrated these birds are adapting in cities and are slowly recovering from the toxic effects of DDT, the main cause of the peregrines decline in North America.
Nash says he will be speaking with the bridge authorities to work with them to help them protect the site.
Transport Canada, Public Works, and Government Services are responsible for the Burlington lift bridge.
Spokesman Sandra Young says the office will be contacting the appropriate wildlife and environmental agencies to find out what they should be doing or not doing to ensure the safety of the peregrines.
"I can tell you, the operation of the bridge won't hurt the nest."
"Reprinted with full permission from the Hamilton Spectator"