Urban Hawks

Tonight, Dr. Robert “Birding Bob” DeCandido, Ph.D. came close to causing real harm to this possibly nesting pair of Eastern Screech-Owls.  He brought a tour of owl watchers into The Loch and played Screech-Owl vocalizations for over thirty minutes.

Just by luck, he was far enough away from the cavity not to draw the female off the nest.  He did however disturb the male, who has been coming to the nest at dusk, hunts and returns within minutes to feed and copulate with the female, who leaves her cavity for only a few minutes.

Tonight, the male did not arrive at the nest until after Dr. DeCandido had left the area. The male owl was tracking Dr. DeCandido from good distance staying at the height of the tree canopy.  Only after he saw Dr. DeCandido leave the area, did he come to the nest over an hour late at 6:20.

It’s harder for the male to hunt this late.  At dusk, both mice and sparrows are more active.  When he arrived the female, joined him almost immediately, expecting a meal.  The pair copulated, then while he began to hunt, she called loudly, as to say “I’m hungry”.  He tried various places, including a wood chip pile but was unsuccessful.  He flew south to other hunting grounds.

The female returned to the cavity.  She then called softly for food for half an hour.  I wanted to wait until he returned to make sure everything was fine, but had to leave to meet a friend for dinner.

I really don’t understand why Dr. DeCandido would be still be leading tours this late in the year.  He’s familiar with this female’s history of nesting too early.  As a scientist he can clearly do the math and knows not to lead tours after January 1st. 

I’m not sure what to do about his tours. 

If I do nothing, there’s a good chance he won’t find the cavity. 

If I do something proactive, I’ll have to tip my hand that there’s a nesting owl pair.  This might lead to more intense and direct harassment.

Who thought owl watching would be so difficult?

Tonight, the male arrived, trilled a few times and then took off as normal to the south around 5:30 p.m.  The female only came out of the cavity for a few minutes
around 7 p.m.  (On the last few nights, the female has left the
nest when the male has arrived with food, the pair has copulated and she has quickly returned to the nest.)

One of the odd things about the reintroduced Central Park owls is how early they have nested.  We’ve had fledglings in mid-March in previous years.  (The early nests may be simply an issue with the reintroduced owls needing a few generations to get their timing right or some more serious environmental issue with the park.)

A female Eastern Screech-Owls typically spends about six days resting before laying eggs, three to six days laying eggs, thirty days after the first egg is laid to incubate, and their offspring take between twenty-four and thirty-two days to fledge.

So the previous early nesting history of this female and her current behavior I would bet she’s nesting now.

Tonight the male appeared, and called to the female.  She made a brief call, and he flew off into the triangle above the bypass road.  He returned with a sparrow, and she flew down to him.  They exchanged the sparrow, copulated, and he flew off south across the North Meadow.

She then ate the sparrow, giving us quite a show.

Although it was still below freezing, the winds had died down making this evening feel warmer.  The squirrels behaved tonight and the female came out before the male arrived.  When he arrived, he flew to the ground but didn’t appear to catch anything.

The couple copulated and the male left.  The female continued to call, and at some point the male returned.  After about an hour, we lost track of both of them.