SAULT STE. MARIE, Mich. — The International Bridge linking Sault Ste. Marie to Canada is more than just a vital link for cross-border freight and travel — it’s also “home sweet home” for one of Michigan’s endangered species.
Several years ago, a pair of peregrine falcons nested on the bridge, and they have returned each year. These resident raptors have had a productive summer this year, successfully raising two chicks. A third egg did not hatch.
Michigan lost its peregrine falcons in the 1960s and 1970s because of the usage of DDT and other environmental contaminants. Since conservation efforts started in the mid-1980s, the number of peregrines has fluctuated, but has generally increased since the 1990s, according to the Michigan Department of Natural Resources (MDNR).
The peregrine falcon has been removed from the federal endangered species list but is still listed as an endangered species in Michigan, protected by state and federal law. Peregrines have adapted to city habitats, nesting on tall buildings, smokestacks and bridges around the world.
Karl Hansen, bridge engineer for the International Bridge Administration (IBA), reported on the pair of peregrine falcons that nested on the bridge between the U.S. and Canada. Nest boxes for the peregrines have been installed on the bridge since 2010 on the International Bridge.
Last year, the same pair of peregrine falcons hatched one chick. Over the years, the site has been a great success, hatching 32 falcon chicks since IBA staff started counting the birds, Hansen said. Several chicks have been banded for tracking.
An interesting illustration of how far the birds can range: one of the birds hatched and banded at the International Bridge was spotted and photographed in the Dominican Republic back in November 2020.
This year’s chicks, a male and a female, were banded by a team from MDNR team in June. Color-coded bands were attached to the legs of the young birds to allow scientists to track the movements, reproductive behavior and population growth of the falcons.
“The mother bird refused to leave the nest this year,” Hansen said. “That was a first. The MDNR staff had to gently remove her to access the young birds.”
In addition to colorful leg bands, the peregrine chicks received names from the IBA staff — the male is Tony, and the female is Franny.
High-speed hunters capable of flying at 200 miles per hour, the peregrines may help keep populations of nuisance pigeons under control. While researchers have found pigeons make up a relatively small portion of the falcon diet, the feathered predators may play a role in frightening them away from bridges. Keeping pigeons away is seen as potentially saving the IBA’s maintenance money down the line, as pigeon droppings can damage paint on metal bridge surfaces.
Several years ago, the IBA added a video camera trained on the nest box, the “FalCam.” The live video stream is available at www.saultbridge.com/falcam. The best time to view the birds is in the spring, when they’re nesting.