There are endless sources of academic documentation about Peregrine Falcons, but learning first-hand is far more exciting. This document outlines some interesting information learned from the Peregrines nesting at our location.

Thanks to the Canadian Peregrine Foundation who have opened my eyes with their wealth of knowledge. The goal of this article is to share this information so we can all better understand these amazing falcons.


Origin of our Peregrines

It took over 1800 photos before the band of the male falcon was finally captured. For the female only a partial band was captured, we still don't have any definitive confirmation on her identity.

Typically, monitored Peregine hatchlings in the USA and Canada are banded with both a silver "US Fish & Wildlife" band, as well as a two-tone band on the other foot (in the USA), or a solid black band (Canada). The female only has a single US F&W band, which leaves us fairly sure that she was born in Ontario. This is based on the fact that at a particular banding event, there was a shortage of two-tone bands and so a female ended up with only a silver band. We believe this is her.


In the case of the male, we know that he hatched on the Gulf Tower in Pittsburgh Pennsylvania in 2002. He spent at least one winter down south before he eventually called the GTA home. He previously nested, we believe, with this female at what was once the "four sisters", the now demolished Coal-based powerplant at the Lakeshore near Dixie Road.

These falcons arrived at our site in late March 2008, but it took a positive band ID to be sure of their identities and origin.



Metrics

Size:

Females are approximately 1/3 larger than males.


The average head-to-tail length of a Peregrine falcon is 15-18 inches for a male, 18-21 inches for a female. Wingspan for a male is 40 inches, and 45 inches (nearly 4 feet) for the female.


Weight:

Males usually weigh 20-25 ounces, females 32-40 ounces






Speed:

While Peregrine Falcons aren't as able at soaring on warm air thermals as hawk or eagle species, they are said to be the fastest flying animals on earth. In a dive, which is how they attack prey, they are known to reach speeds of over 300 kms/hour. (view National Geographic video here)



Diet:

Observing our falcons and what's left of their prey reveals a strong preference for Grackles. They have also been noted capturing Blue Jays and Starlings. Don't feel too bad, Blue Jays are predatory too - that's one less Blue Jay raiding Robin's nests. Once the task of feeding offspring is underway, undoubtedly, larger birds like pigeons and small ducks will be on the menu.

Peregrine Falcons feed almost entirely on birds. They generally capture prey in the air, by executing a steep dive from above, then "stooping" on their prey, knocking them with their talons in a way that instantly kills. They then proceed to catch the bird as it falls.




Threats:

The Peregrine's sworn enemy in nature is the Great Horned Owl. Able to hunt under the cover of darkness (when Peregrines are motionless and defenseless), Great Horned Owls are a Peregrine's natural predator.

Man is another well documented threat to the Peregrine. Poaching from nests, capturing of birds, and poisoning through such activities as pigeon and other pest control, have all had disastrous effects on Peregrine Falcon populations.

Of course the most significant threat to the Peregrine Falcon is the pesticide DDT, which nearly caused the extinction of the species. The banning of DDT use in North America since the early 80's has assisted in the Peregrine's recovery, but this pesticide is still used in Central and South America, and is therefore still a very real threat to Peregrine Falcons since many spend the winter down south.



Nesting:

In nature, Peregrine Falcons typically choose south-east facing cliffs for their nesting location, usually 100 feet or more from the ground. They have been observed in the wild nesting on cliff ledges as small as a football! In an urban environment such as ours, once again they prefer south-east exposure, and heights of over 100 feet.

While many bird species build nests with twigs and grass, the Peregrine Falcon is content to nest on gravel. In cases where the Canadian Peregrine Foundation knows where nesting is likely to take place, nest boxes containing round "pea" gravel are implemented in advance of breeding season to provide an optimal substrate that eggs can safely be laid and rolled around on during incubation.


Migration:

Historically, Peregrine Falcons, especially those located in more northerly locations, will summer north and migrate to Central or South America for the winter.

In an urban setting like Toronto, juvenile Peregrines will still migrate south for the winter, while their parents will often stay in the city where even in the coldest months they can find enough food (ie. pigeons) to survive.

Part 2 - Courtship & Mating...

Article & Photos - Mathew Rossi 2008