Longer days

Eastern Phoebe in the Spring --
photo by Cal Vornberger http://www.calvorn.com


The days are getting longer. At its earliest, sunset was at 4:28pm. That was on December 12th. Today the sun sets at 4:37pm. Those nine minutes make a difference. Of course sunrise is still getting later each day, and won't start receding until January 10th, when our star will rise at 7:19am, one minute earlier than the day before. Even though the Early birders are meeting a half hour later these days, it is still not full day in the park at 7:30am

Well, you can't have everything. The days are getting longer and the whole animal kingdom feels it. Even homo sapiens senses the change,[ and we are not the kingdom's most sensitive subjects, after all.] The red-tailed hawks will soon begin serious nest building and love making-- all because of the longer days. The squirrels and raccoons will be family minded. The grackles are already gathering in huge flocks. Within weeks we'll start hearing [on warmer days] the spring calls of the cardinals and titmice.

The arrival of the Eastern Phoebe, one of the earliest spring migrants, is less than three months away . I'll be in the park looking for it around March 12th.and then for the next few days. It's sure to arrive by March 17th. Maybe I'll see you there.

HAPPY NEW YEAR, website friends!

Bald Eagles nesting in Central Park? John Blakeman discusses

Adult Bald Eagle with Striped Bass flying by Pale Male at the Beresford
Photo by Lincoln Karim - 12/27/06



Marie,

Lincoln's remarkable photos of the adult bald eagle carrying a striped bass over Central Park prompts me to describe typical red-tailed hawk behaviors when our hawks encounter these giant eagles.

The bald eagle is generally presumed to be a fish-eater, confined to shorelines, rivers, and large wetlands, where fish are easily captured.

But in fact, the recent explosion in bald eagle numbers (from a dozen or so in 1979 to close to 600 today in Ohio) has revealed that this eagle can be as opportunistic and adaptable as is the red-tailed hawk. Back in the 70s, when DDT still suppressed bald eagle reproduction, it was hoped here that perhaps a dozen eagle nests would some day recur in the great marshes along Lake Erie's south shore.

In fact, over a dozen new nests appeared by the mid 80s, and bald eagle restoration was deemed a great success. But not by the eagles themselves. Instead of confining themselves to classic lake, marsh, and riverine nest sites, new eagle pairs went inland and built nests just like red-tails, out in isolated woodlots overlooking mere corn or soybean fields. No one ever thought they would or could do this. Today, bald eagles nest in most parts of Ohio, just as they now do in most parts of the Empire State. These inland birds still eat fish when they can, but a large portion of their diet is now mammals, either captured outright, or often from roadkill.

Last winter I watched an elegant adult bald eagle feed on a roadkill deer carcass for most of January.

Our red-tails perceive that bald eagles will kill and eat whatever is convenient, including red-tails. When I am hunting with my falconry red-tail, from time to time she will instantly take a compressed, diligent posture on my fist as we walk through the meadow searching for cottontail rabbits. Instead of standing erect and peeringforward with intense interest in any fleeing rabbit, Savanna turns her eyes to a distant bald eagle she has seen and remains fixed on it until it completely disappears.

She knows that if bald eagle sees her on the ground (or she thinks, on the fist), the eagle will think her to be injured or incapacitated and she will be attacked by the approaching eagle. When an eagle appears (rather frequently now, with over a dozen nests in my immediate area) Savanna and I just stand there and watch the giant raptor's passing. Savanna is in no actual danger because of my presence. But she has a decided fear of these big birds when they approach.

Pale Male almost surely had the same concerns when he saw the eagle passing through the lower altitudes of Central Park. But just as Savanna resumes her intense hunting, Pale Male resumed his normal activities when the eagle passed from view.

I don't think a bald eagle is likely to erect a nest in any Central Park tree any time soon, so Pale Male has little to worry about. But of course, back in the 90s I presumed that no red-tail would productively nest in Central Park either. Bald eagles are now adapting to modern American life as well as red-tails have, so I'd better not make any definitive pronouncements of where eagles might nest next.

--John Blakeman

Question & Response

The three intact eggs retrieved from the 2006 nest at 927 Fifth Avenue before being taken to Ward Stone in Albany for analysis.



Kathy Guchone wrote:

Hi Marie ,

Happy Holidays to you and to all the NYC watchers.

I have a question regarding the spikes in the new nest cradle. Does anyone know if the new spikes are the same length as the spikes in the old, removed nest. If the new ones are longer maybe this was done on purpose to discourage the hawks from producing babies and perhaps eventually moving on. Maybe this sounds paranoid on my part but couldn't this have been a more subtle way the the coop people could have gotten their way after all. As you can tell I think very little of these coop people.

Thank you for your time

Kathy Guchone

Dear Kathy,

And a very Happy New Year to you!

As for your question: There are no new spikes. When the nest was taken down the super, for some unaccountable reason, saved the wooden strip with the spikes. Later, after the building relented, this same strip was attached to the new "cradle" that was put up on the ledge for the hawks, .
The coop was terrible to take the nest down in the first place, but I don't see how they could have done anything to hurt the hawks' chances for success once the crisis was resolved.
Of course it IS possible that the subsequent nest failures had something to do with the "cradle". But that can't be seen as a deliberate thing on the part of the coop. In any event, the spikes are not to blame. Pale Male had ten successful years with those same spikes at the base of his nest.

PS A clincher: When the eggs were removed for analyses last spring all three were intact. If the spikes had damaged the eggs then the eggs would have been...well, damaged.

PS: Location of Red-headed Woodpecker

PS- For those wanting clear directions on how to find the Riverside Park Red-headed Woodpecker's roost tree, Ben Cacace's blog includes a Google Map of it. Here's a link:
http://novahunter.blogspot.com/2006/12/
riverside-park-red-headed-woodpecker.html

Blakeman: Is the nest bigger?

The nest --Photo taken on December 9, 2006 [two weeks ago]

The nest -- May 2005 [more than 18 months earlier]


I sent a note to John Blakeman asking him to comment, based on photographs available on Lincoln's PaleMale.com website, whether the nest looks noticeably more substantial this year than last. After all there was a big flurry of nest-building activity in December and January 2006. Here is his answer:


About the depth of the nest.

From the photo, it just doesn't look like the nest itself is much thicker or deeper than before -- which is your concern, too.


As I mentioned at the very beginning, it appears that red-tails bring sticks to the nest and tuck them in only as long as the entire mass of twigs and sticks are loose. Once they consolidate into a larger, cohesive mass, the birds stop concerning themselves with the nest's size. When it feels solid, they perceive the main nest structure to be complete. After that, they tend to proper lining of the nest, bringing in leaves, grass, and other loose materials to form the egg-supporting bowl.


If the nest feels solid, there is no impelling need for the 5th Ave pair to do much nest tending. As either of the birds walk around or sit in the nest, everything feels solid and secure. The pigeon prongs artificially knit the whole mass of sticks together.


But you've seen them bringing sticks to the site, so how does that fit in with my contention that they aren't really concerned about making the nest deeper? The important factor is what do they do here in December and January with the brought-in sticks before nest refurbishing becomes a powerful behavior just before eggs are laid in March. Bringing sticks to the nest can be either useful, or merely incidental to the birds' experiences and presently minor breeding behaviors. To be of any effect, the sticks have to be not only brought to the nest area, but they must be deliberately tucked into the central nest structure (not the metal support).


The birds can incidentally bring sticks to the nest and more or less leave them perched loosely on the top or edges of the nest proper. A good winter wind will blow these off and be of no use. Useful sticks are carefully tucked in sideways between other sticks and locked into the structure. Those sticks won't be lost to a wind gust up there. But they will contribute to a deeper nest.


So nest watchers need to see what the hawks are doing with the sticks once they are brought to the nest. Are they being ritually dropped and allowed to lay free (and useless) along the edges, or are they being taken into the bill and tucked sideways down into the existing central pile of sticks?


That will tell if the nest is going get thicker this season. If it does, we will have the best chance of resumed reproduction. If not, things may continue as they have for two consecutive seasons.

And it's appropriate that you've mentioned this just at the winter solstice period. By mid January, the birds will notice that the sun is rising earlier, and setting later. More importantly, there will be a few more minutes of daylight each day, as the winter progresses. We groundling mammals concern ourselves mostly with winter temperatures. Red-tails have remarkably insulating feathers. (Do we realize how cold we'd be drifting through 0-degree F winds at 40+ mph?) For the hawks, it's not the temperatures that control much of anything. For them, it's lengthening daylight periods, which initiates a cascade of hormones that prompt all of the breeding behaviors.


It's understood that even the loss of daylength (reduced "photoperiod") which happens in autumn, especially in November and December, can prompt a modicum of breeding or nesting behavior. That's what's been prompting the sticks retrievals to the nest so far. As the photoperiod begins to lengthen in January, the hormone prompts will be increase significantly and by early March will be the overwhelming behavioral drivers for both birds.


So the 2007 breeding season has actually begun, albeit so modestly or ritualistically just yet. Nest watchers should be attentive in recording what happens to the brought-in sticks. Are they dropped onto the nest (not effective), or are they actually tucked into its structure?


--John A. Blakeman

---

A heartwarming incident for Christmas reading

Adult Red-headed Woodpecker

How many times have we seen starlings oust weaker birds from their hard-earned roost-holes and nest holes in Central Park. I'd never heard of a starling on the losing end of a battle until this report from Ben Cacace's blog: Http://novahunter.blogspot.com He is referring to the uncommon Red-headed Woodpecker that has been roosting in Riverside Park, just outside the building I live in at Riverside Drive and 92 Street, for the last week. It may stay until spring.

Woodpecker vs. Starling

There was an incident between a starling and the woodpecker. Around 4:10pm a starling was perched near the freshly made roost hole created by the woodpecker. When the woodpecker flew a short distance away from the hole the starling beelined it to the hole and made itself at home.

Almost immediately the Red-headed Woodpecker flew to the edge of the hole, peered in a few times and then entered it and somehow came up with a starling. When the intruder was brought to the edge of the hole both birds started to fall and just before hitting the ground they separated. The starling flew back up to a perch near the hole.

The woodpecker returned and perched at the hole's edge. The woodpecker peered in it a few times and then entered but left a few moments later. The starling was still in the same location above the hole. At this point the woodpecker decided to fly at the starling a few times which eventually drove it off towards the north. The starling never returned to bother the woodpecker.

Roost Hole

I went to the site tonight [December 24] to see if it was possible to find out where the woodpecker would roost for the night. I've followed the roosting activities of wintering Red-headed Woodpeckers in Central Park and found this a rewarding activity.

Tonight the event took longer than I thought it would. In the past, I recalled the Red-heads would go to roost well before sunset. In those days I would watch a Red-headed go to roost and then would have plenty of time to arrive at the Long-eared Owl roost to watch them fly out.

Tonight at 4:38pm, 5 minutes after sunset, the Red-headed Woodpecker entered the hole the starling attempted to take and after dipping its head in and out roughly 30 times it entered for the evening. The woodpecker was visible for a short time afterwards since it poked its head out a few times giving three by-standers great looks in the waning light. Also at the post fly-in were Mike Alcamo and Marie Winn.

Postscript from Marie

It seems to be December 25th. Have a merry day.

Red-headed Woodpecker and 2 corrections

Oops --holiday chaos created warbler chaos and I posted the wrong warbler in the report below. [I wrote Golden-crowned Warbler] It's now corrected.Thanks to several correspondents who sent in gentle reminders of the mistaken identity.

PS The woodpecker is correct., but I reported the wrong discoverer in my posting of 12/21. Lenore Swenson discovered the bird while scouting Riverside Park for the Christmas Count.

The Riverside Park Red-headed Woodpecker
Photo by Cal Vornberger
[Imagine that brownish head bright bright crimson and you'll have an idea of what this bird will look like next spring.]

The unusual woodpecker is still hanging around the same roost hole at 92nd Street and Riverside Park. And now another bird is putting Riverside Park on the map: a Cape May warbler has been seen for several days at 115th Street, near the park wall, feasting on sap that a Yellow-bellied Sapsucker has obligingly made available by drilling multiple holes in trees.