Sunday, January 15, 2006

Blakeman: more on GHO's --Marie responds--


GHO just before fly-out
Photo by Bruce Yolton

A note from John Blakeman -- 1/14/06

Marie,
A nice posting on the owl, by de la Torre. Absolutely accurate on every account.
One additional note on great horned owls. Their numbers are reduced in many areas of the East and Midwest from the West Nile Virus wildlife pandemic that recently shot across the continent. Owls apparently got pretty zapped by this virus. Large numbers of great-horneds were brought to raptor rehabilitation centers. The big owls appeared to be particularly vulnerable, and there was some evidence that they poorly acquired post-infection immunity. The birds weren't wiped out, but their numbers were significantly reduced in many broad areas.
Great horned owl numbers have probably not recovered to those of pre West Nile Virus days. Consequently, there are fewer "floaters," unmated young adults looking for mates and territories. This reduces the chance of the Central Park owl finding a mate this year or next.
Have I noticed in the owl postings that the bird has been observed flying off at night toward a Central Park lake or two? It's not going over there to hunt for fish. To me, this indicates that the bird has noticed the waterfowl sleeping in the area. We'll see what happens, if anything.
Sincerely,
--John A. Blakeman

Response from Marie

1. I agree that the owl is not at the lakeside to fish, though I have heard of GHO's standing in shallow water and catching fish.

2. There are always many rats at the lakeshore areas to which the CP horned owl has consistently flown after fly-out. Not sure why -- perhaps people leave food remnants there, people always being attracted to water edges. That in turn would attract rodents. Or perhaps the emergent vegetation at the shores have seeds that bring in rodents. I would guess that these rats are what the owl is hunting.

There are, indeed, many mallards and other waterfowl in the lake during the GHO's hunting period. They don't seem to be sleeping. I see them in the lake right near the tree where the owl is perching, dark shapes gliding in the water quite near the shore.. I've watched the bird in the tree for long minutes, trying to see if there's any sign that he is paying attention to these ducks swimming right past him. No head movements indicating this. As the owl perches, ducks all over the lake are quacking every few minutes - to the left near the Lower Lobe, to the right near the Ladies' Pavillion: Quack, quack-quack, quaaack. Again, no sign by head movement that our owl with his/her phenomenal hearing is paying attention. When he's not doing his pussy-cat preening-- from our vantage point below the owl SO resembles a large cat doing a thorough fur-lick -- he seems to be looking intently down at the ground.