At that distance, in that amount of light…

This morning, while I was off running in the dark, I became very glad that I take the same route almost every morning.  For some reason it seemed like a darker morning than normal.  That could have been because my eyes were less open than usual, but I’m not here to speculate on that difference just yet.  Either way, it was pretty dark.  Silhouettes were rather easy to make out, but not much else.

Anyway, I began running through Freedom Park.  I circled the lake, like normal and was about to cross the bridge into the parking lot to continue on towards East Blvd when a shape caught my eye.  It was about 50 meters away, sitting on the dirt path that runs along the creek.  The shape was definitely hunched over and I could make out black and white stripes on the head.  An Osprey?  At Freedom Park?  Unheard of!  Well, maybe someone has heard of it, but I haven’t.  I know there are fish in Little Sugar Creek and various fish in the lake there, but it doesn’t seem quite like the spot for an Osprey to thrive.  Kingfishers regularly patrol the creek and I’ve seen them hanging around the lake, but they require a lot less fish.

Suddenly, I became fascinated with how an Osprey could possibly use that particular habitat.  Are there enough fish in that lake to support a resident?  I don’t have answers to these questions.  I did, however, spend some fun time reading about Osprey energetics.  One study actually followed male Osprey around during the breeding season to find out how much time they spent hunting.  On average, the birds spent only about 1.5 hours a day in hunting flight.  This amount of time was even true when the male was providing food for the female and the chicks on the nest.

Green, D.J. and R.C. Ydenberg.  1994.  Energetic expenditure of male Ospreys provisioning natural and manipulated broods.  Ardea 82:  249-262

Using data that they collected on activity patterns, the energetic values of fish and how long it takes an Osprey to eat a fish, these authors estimated daily energy expenditures and intake rates for the birds in their study.  They found that these birds were certainly not stressing themselves out (energetically speaking) by foraging for that hour and a half a day.

The only factors that seem to increase the amount of time that an Osprey spends hunting is the amount of wind (and the subsequent change in the water surface).

Machmer, M.M. and R.C. Ydenberg.  1990.  Weather and Osprey foraging energetics.  Canadian Journal of Zoology 68:  40-43.  

But I still haven’t answered the question…could an Osprey really do well at Freedom Park.  All these thoughts ran through my head while I squinted to figure out what the Osprey was doing there this morning (and why it was on the ground).  I was already planning observation time to get down to the park to see if and how it was hunting and wondering how I could find out more information about the fish populations in the lake, when suddenly, it started to move.  I gasped a bit as it turned away from me and its long tail twisted around behind it.  At that distance, in that lighting, my spectacularly weird Osprey sighting turned out to be just a cat with a white stripe on its head.  Sigh.  All that excitement for naught.


About thomasbiology

I'm an Associate Professor of Biology at Queens University of Charlotte with a background in animal behavior with an emphasis in bird song. I've got two secret goals with this blog (well, since I'm sharing them, they're not so secret): 1. To encourage people to look at the natural world around them- not just as a hiking destination, but to notice all the little things moving around them all the time; and 2. To show some of the science that relates to these little things moving around. There's some really fascinating research out there that so few people get to see.
This entry was posted in birds, ecology, foraging, raptors. Bookmark the permalink.

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