May 10 2013
Matthew Richardson had a visitor on his balcony at Point Park University yesterday.
Who is that bird perched on the railing? Certainly not a robin!
The peregrine preened his back feathers and looked headless for a moment.
Then he stretched…
…and looked at Matthew.
Louie was taking a good long look.
Did you know that when peregrines look at you from a 40 degree angle they’re seeing you with their very best vision?
On Monday I met Chris Saladin who monitors peregrine falcons in Ohio. Chris and I have corresponded in email for years — and you see her photos on this blog — but we had never met. It was great to get to know her!
Chris and I stopped beneath the Ohio Turnpike bridge in Cuyahoga Valley National Park where Rocky and Lara nest. We chatted about peregrines while Rocky flew around and checked his cache zones. Then he perched up high and looked at us obliquely. I knew he was watching us but Chris said, “He’s seeing us really well right now.” From an angle? Here’s why.
Everyone’s eyes have their highest visual acuity at the fovea, the small depression on the retina that holds the highest concentration of receptors and nerves. In humans this is 4-8 degrees off center but in peregrines, it’s at a 40 degree angle from their straight-ahead vision. When they dive on prey they circle downward on a logarithmic path that keeps their highest vision on the prey below.
Chris told me that when a peregrine merely wants to look at you he doesn’t have to face you. When he looks straight on, watch out! Chris had just experienced this with Stammy (Dorothy’s son) in Youngstown after she visited his nest to check on his nestlings. Click here to see Stammy coming straight at Chris.
(photos by Matthew Richardson)