Saturday, January 06, 2007

Osage Oranges: Blakeman comments

Blakeman elaborates on the Osage Orange. In Central Park a fine specimen, often with the bizarre fruit scattered at its base, may be seen at Tanner's Spring. I find it interesting that while the Ohio legend has it that Osage oranges repel spiders, the Big Apple version has them fending off cockroaches.

Osage oranges are the fruits of the Maclura pomifera tree.. Here in the Ohio, they were planted in the 1920s and 30s as hedgerows, where they were planted so close as to turn cattle (not hogs). These short trees have thorns. They were also supposed to stop wind erosion (which actually isn't much of a problem here).
Another advantage of the tree was the wood, which is extremely hard and long-lasting. It was supposed to provide durable wooden fence posts, before metal ones became common. But it was discovered that cutting of the large limbs to make fence posts was extremely difficult. The wood is very, very hard. After slicing off one or two 4-inch thick side branches, the saw had to be re-sharpened.
Consequently, there are a few old, neglected osage orange hedgerows left bordering Ohio farmlands. But the species is not native to Ohio (or Central Park). The tree originates in the Ozarks and the surrounding region. It survives winters easily in the upper Midwest and the East.
It is an otherwise useless tree, having no real purpose outside of its native range. Here in Ohio, the big fruits are claimed to repel spiders. Many farm houses used to have fresh osage oranges placed in the basement each fall. But I'm not certain that the spiders were really repelled. Popular mythology often overrides reality (red-tailed hawks eat lots of chickens and game, it was thought).
--John Blakeman

Friday, January 05, 2007

What are these?

Eleanor Tauber, one of the Early Birders, sent a photo she took of the two strange objects [above] she encountered in Central Park day before yesterday. She wondered what they were. In case you too have encountered something of the like, about the size of a large orange or a small grapefruit and looking like a yellow-green brain, here is my answer:

Those are the non-edible fruit of the Osage Orange tree. I once saw them on sale at a Green Market somewhere as an anti-cockroach remedy. [Don't think it works.]

Thursday, January 04, 2007

Attention Central Park Hawkwatchers

Bringing a stick to the nest - December 2006
Photo by Lincoln Karim

Bill Trankle asks: Any info from the eagle-eyed hawk watchers?

The Indianapolis correspondent sends an appeal:

As per John Blakeman's recent post on the nest, I was wondering if any of you keen observers had noticed what PM and Lola are doing with the twigs they're occasionally bringing to the nest? I see by Lincoln's photos that they are doing so now and then, but don't know if you guys have been around when they have to see the disposition of the sticks. I'm quite concerned that the spikes might make the nest seem tight enough that PM and Lola don't add much to it this year, possibly leading to another failed clutch. Still, I'm heartened by PM's stick-gathering behaviors, and I'm hoping he's tucking rather than dropping them!

Bill Trankle

Wednesday, January 03, 2007

Blakeman clarifies: Eagle vs. Redtails

Bald Eagle with Striped Bass over Central Park - 12/27/06
Photo by Lincoln Karim


Let me clarify.

Red-tails definitely will fly up and confront a bald eagle (or any other raptor) that ventures into the hawk's defended territory. I wasn't so clear in my earlier posting that my hawk was cowering in retreat when a local bald eagle ventured into the hawk's remote hunting territory, not its nesting territory.

It works like this. If the hawk finds itself out in the field, away from the nesting area and has the perception that it might be in the eagle's nesting or hunting area, the smaller hawk will make every attempt to retreat or hide, not wishing to be confronted by the big eagle which has territorial dominance. That's the case when a bald eagle flies into our cottontail rabbit hunting area. When hunting, Savanna, my six-year old falconry red-tail, decidedly wishes to retreat or hide from an eagle passing nearby. Savanna perceives -- accurately -- that in her hunting she has ventured out into "eagle space" and could be lethally attacked.

But things are different when an eagle ventures into "hawk space," into the region around a nest, as much as a mile's radius or more out in rural areas. In this case, the hawk will boldly fly out to let an approaching eagle know that it's intruding and ought to high-tail itself out of the space. The smaller hawk is actually more maneuverable than the giant eagle, so when motivated, it can fly circles around the big bird (just as blackbirds and crows can do with red-tails).

If the resident hawk perceives that a passing eagle is entirely in transit, just passing through, as was the case with the Central Park eagle with the fish, it will often stay perched and allow the eagle to pass on through the hawk's territory unchallenged. But, if the eagle were to wheel around and claim some local air space, or take a nearby perch, it would be directly challenged in winter and spring, when nesting territories are more firmly defended.

If the hawk sees the eagle passing well over head, it will never be challenged. Red-tails defend a wide (but variable) radius of territory extending out from the nest, but only a few hundred feet of elevation. Intruders passing high enough over head almost always to unchallenged. The resident hawks know that other elevated hawks or eagles pose no territorial threat.

I hope that clears up the "Hawk Challenges an Eagle" question.

--John Blakeman

Tuesday, January 02, 2007

Redtails and Bald Eagles

Bald Eagle with fish over Central Park - 12/27/06
Photo by Lincoln Karim
[Click on the photo to enlarge!]

A few days ago I posted Lincoln Karim's remarkable photo of a Bald Eagle doing a fly-by of Pale Male who was perched at that moment on a tower of the Beresford [Central Park West and 81st Street.]. The eagle was carrying a fish that John Blakeman identified as a striped bass.

The posting about the eagle fly-by elicited some interesting comments from John Blakeman. He noted that red-tails usually prefer to stay put, rather than confront a bird so much bigger than they are .

Here is a link to Ben Cacace's blog, where you can read his comments about Bald Eagles over Central Park, and also see a photo that seems to contradict Blakeman's idea that red-tails will not challenge Bald Eagles.

Monday, January 01, 2007

"My" rare woodpecker

Red-headed Woodpecker -- December 31, 2006
Photo by Barrie Raik

It's wonderful to have a special bird right across the street from home. Not only can I stand at my livingroom window with binoculars and easily see the woodpecker flying around its area, or perched in the vicinity of its roost hole, but I can stand in the same place and see a variety of Central Park birders arriving to pay their respects to this unusual visitor.

Yesterday as I was standing in front of the bird's tree on my second visit of the morning before beginning work--[yes, what I was doing is known as procrastination] there was Barrie Raik, a Central Park birder. I spend many Tuesday mornings during the spring migration walking around Central Park with Barrie [and about 20 other birders] as part of Steve Quinn's Museum of Natural History 7 a.m. bird walk.

Barrie was testing out a new camera lens yesterday. The result was the stunning photo above. I think that lens was a keeper, don't you?

PS If you look very hard you'll see the first red feathers coming in at the lower part of the woodpecker's head. If he or she stays all winter we'll have lots of fun watching the head redden as the bird begins to fulfill its name.