Saturday, March 20, 2010

Mute Swans, Great Horned Owls, Squirrel Nabbing Red-tails and I Make a Nest

Photo by Paul Anderson
Mute Swans,
Cygnus olor
Actually they aren't mute they hiss and wheeze. They're the ornamental park variety, exotics which have become established in the wild. They eat aquatic plants and seeds, which one of them seems to be doing, with head and neck disappeared into the water. The other is keeping a close eye on the activities of the nearest duck.

Photo by Paul Anderson.
Exactly why the huge swans feel the need to keep such a sharp eye on the much littler ducks I don't know. Perhaps swans have a need for a particular allotment of personal space--or else.

Photo by Richard Fleisher

Photos of the Great Horned Owl 3/17 at the Botanical Garden.

Beginning to wonder, I am no expert on GHO but it seems to me that we are either approaching or past the normal gestation period for a GHO (average of 33 days).


Is it possible that there has been a hatch but we just haven't seen the owlets yet as they aren't old enough to peek out? Not much chance that the NYBG is open at night so you'd be able to see if both parents fly out to get food for the little guys. Though to tell the truth, I know that both Screech Owl parents will go out to forage for the young come evening but I don't know if that is the case with GHOs.

Photo by Richard Fleisher

Photo by Richard Fleisher

Photo by Richard Fleisher
Hmmm, looks kind of grumpy doesn't he?

Photo by Richard Fleisher

Photo by Richard Fleisher


I had another adventure today at the NYBG. I recently purchased a small HD camcorder and took it with me into the forest for the first time. Incredibly, while not too far from my previous encounters with Rose and Vince, I saw this beautiful raptor touchdown on the top of a tree. As I got closer, I noticed it was playing cat and mouse with a potential meal. A tough NYC squirrel. I got some video. The squirrel lived to run another day.

I'm not sure if this hawk was Vince, or the juvenile Red-tail I saw at the Twin lakes last time or perhaps another hawk.

Click this link for the video.

If this is Vince, Rose won't be eating many squirrels while sitting the nest. It is a very common sight to see a young Red-tail attempting to nab a squirrel that's in a tree. It just doesn't happen, not if the squirrel is healthy and smart enough to stay in the tree--and most all of them are once they know the hawk is there.

As anyone knows who as a child tried to get a close look at a squirrel hanging from the trunk of a tree, the minute you come closer they just head for the other side of the trunk--and they can do it all day. Even a Red-tail who has managed to herd a squirrel out on an isolated limb is still out of luck as squirrels can scoot round to the bottom of the limb and then back up again behind the hawk.

The secrets on the hawk's part to squirrel nabbing is stealth and patience.

First, the hawk must come in and perch without attracting any notice. If the hawk is noticed all the squirrels in the area will sit on limbs and whine at him, and whine, and whine until he gives up. And as we know a squirrel on a limb is not dinner.

Second, once perched without notice, the Red-tail must be patient and not give himself away by making a vain attempt at a squirrel in a tree. He must wait until a squirrel is on the ground and far enough from a tree for the hawk to make his move, grab the squirrel with a very firm grip, squirrels John Blakeman tells us have very tough skin, and then put it out of commission before the squirrel can damage the hawk. Squirrel grabbing is quite a dangerous business. Those teeth and an ensuing infection can mean a hawk's demise.

TANGENT: I had a cousin grab a squirrel by the tail who was used to being hand fed. The squirrel curled right back up to his tail and bit clean through her thumb. Obviously something to be avoided.

If you want to see the photo without the watermark, please go to my flickr page.
Once there, click the file marked red-tail hawks 2010. The two photos are called chase1 and chase2.


Photo by D. B.

What is this you ask? This is my experiment in hawk nest building. Okay, okay, it was an idea that, well, progressed.

You see, when I'd pick up fallen twigs before mowing, no don't get me started on mowing, for some time I'd piled them up against the house near the feeders to make a refuge for the smaller birds so they could whip into the pile and not be such easy prey for the Cooper's and Sharpies.

Yes, I know everyone has to eat but as the feeders are unnatural they also gave the Accipiter's an unnatural advantage. Just trying to even things out, folks.

Okay, back to the pile of twigs. The pile had grown taller than me and people began to tell me having them piled there wasn't good for the house. Plus it would draw mice, who eventually would want to take up residence in the house.

As the weather was good finally I began putting the twigs into a wheelbarrow. Now, I've always wondered if I actually knew with any specificity what was actually needed to make a nest hang together. I mean how many times had I watched Pale Male stand on the nest for many minutes on end staring at certain spots of the nest, making a decision, and then setting out to rectify whatever problem he was seeing.

By the time I'd trundled the barrow across the yard, wondering where I was going to put the refuge, I'd decided that if I put the many barrows full between the maple and the spruce I could experiment with "nest building". I admit I didn't put them on one twig at a time. I began by piling some up. The "wall" developed bulges that looked like it would give way.

Ah ha, that's where the vertical twigs would come in. I stuck some in. Jiggled them, and wiggled them. Firm? Stared. This helped the current problem but made others visible or created them. I stuck in some more. Stared. Suddenly I realized that Pale Male's staring was comparable to a beaver listening for the trickling of water. The danger signals for nest imperfection being visual after all.

I also had seen Pale Male attempt to put a twig into the nest in a variety of places and then lay it down as if he'd just lost interest in the process and go find another twig. I realized this wasn't Attention Deficit or lack of interest on his part, he'd just come up with a twig that wasn't workable for any of his known problems and therefore had gone off to find one that would work.

After using up my many barrows of twigs, I felt itchy for more. I noticed that the neighbors had been pruning their woody plants and had laid a whole new pile of small branches, potential twigs, out by the street for the city to pick up. I was having twig envy. I wanted those twigs.

You just can't go marching up and take the neighbor's pile of sticks even if they are throwing them away. I was going to have to 'fess up and ask them if I could have them. Boy is this going to sound really weird to regular non-hawkwatching people. It probably sounds pretty weird to even hawkwatchers but I needed those twigs.

So down the sidewalk I went, explained my purpose for wanting the twigs, "I'm experimenting with how hawks build nests..." a slight pause, a few good natured laughs on all our parts, and then they said sure, take 'em, and even helped me fill the wheelbarrow.

Thank goodness I already have an accepted reputation for eccentricity in the neighborhood otherwise....

Donegal Browne

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