Just curious....how do other falcons know to stop at the Radisson? The hotel is not the tallest building down town. there is food flying around all over the city? Just want to know how they know??
The falcons are looking for spots to roost (at this time of the year) and places to nest (in the spring). It might seem simple to think that any roof will do, but its not that easy I'm afraid, they aren't looking for flat tops, but rather cliff ledges - small horizontal space, inaccessible to predators, good nearby vantage points beside the nest and nearby from which to watch the nest, spots to roost, spots to preen, spots to eat, spots to court/pair bond, spots to defend the nest from. And many of these spots are mutually exclusive. They use the Hotel's antennae, the window ledges (chicks mostly) both signs and the nest ledge. They also use other signs - Hydro, Rogers, Royal Bank, Canada Post, City Place and the Richardson sign. Haven't seen them use the Canwest sign, might be too exposed to the wind. They use other buildings too - Kensington, Paris, Sterling, Royal Bank, Canada Post and the dome at the corner of Garry & Portage. Most of those buildings are lower and have architectural features that make them different from the steel and glass around them. Kensington is a steel-and-glass, but its right across the street and its really only Ivy who has used it.
The Radisson downtown is unique in that hit has a nestledge on every single window ledge or in the cast of the east-side nest ledge, on a small roof. We improved the appeal of the nestsite by installing nesting boxes that had more protection, had pea gravel (a requirement and not common on rooftops anymore) and was where the birds were going anywhere. The Radisson is only one of 5 buildings downtown that had nestboxes on them - it is the only building they chose to nest on despite about 10 years of releases at these other sites. The features they like on the Radisson can be found at every other site they nest or where there is a history of roosting on migration or where non-breeding juvenile birds hang out.
Does that help ?