Saturday, May 06, 2006

From Donna's website

Photo by Eleanor Tauber

The charismatic Raccoon who lives just north of the Model Boat Pond first charmed the Hawk Watchers while they waited for Pale Male and Lola. She's now begun to draw crowds of passers-by everytime so much as her nose appears in the opening of her cavity.

Grackle Update

Common Grackle--May, 2005
Photo by Lloyd Spitalnik

Remember Veronica, the Personal Shopper at the Bergdorf Goodman Department Store whose dressing room for clients looks out on the Grand Army Plaza,? She has sent in several reports about the huge flocks of grackles that roost every night in the trees surrounding the fountain there. She has just sent in the following news.:


As we have experienced the realities of nature this chilly spring , I should also tell you that the "ballet of the grackles" no longer performs outside my window at Bergdorfs. Alas, they have all moved on to find their own new nesting sites. It was wonderful while it lasted. Sorry about all this grim news. [about the hawk nests failing] .Good news is that the pair of falcons at 55 water street did get an egg to hatch...........


Friday, May 05, 2006

Do Redtails form a bond to their young? John Blakeman answers

Pale Male & Lola, still attending nest, May 4, 2006
Photo by Lincoln Karim

Today a letter arrived from a website reader; I promptly forwarded it to John Blakeman.

The recent letter from John Blakeman was very interesting and brings to mind a question.

On the one hand Mr. Blakeman has observed a wide variety of emotion from Red Tails and on the other no emotional attachment to eggs or eyass's. What I'm wondering is if the parent RedTails ever develop any kind of bond to their young, perhaps shown during times of first flight or later on as the grow, or do they always act like its a job and things get easier for the parents on the young grow up and eventually leave the area. It seems from a strictly survival point of view such an approach would be best for the species.


Karl Nicholas

John sent the following informative, hard-hitting response :

Karl's question is a good one. If red-tails can get rather animated, even downright "emotional" in their hunting, how is it that they don't express much emotion toward their young? I've said that adults' behaviors toward their eggs and young are rather mechanistic and not thoughtful in any mammalian sense.

Let me try to explain in more detail. We falconers are always amazed at the behaviors of nesting raptors. They are so different, even aberrant, from what these predators do for a living. All of the behaviors associated with red-tail nesting, from copulation, to nest building, to incubating, to feeding eyasses, and lastly, to tending newly-fledged eyasses, are all in conflict with red-tails' normal, day to day behaviors and views on life. Let's be clear. These birds are predators, profound killers. They make their living by successfully and repeatedly killing other animals. Any red-tail that fails to learn how to kill soon dies. Forty to sixty percent (or higher) of fledged red-tail eyasses never attain adulthood. Most die in their first summer. They fail to learn how to hunt and kill.

A red-tail's life is not dependent on mating, copulating, nest building, incubating, or tending eyasses. The hawk's life depends on its ability, throughout the year, almost every day, to find and kill other animals. That's what every red-tail is programed to do. Just as a four-year old boy is programed to throw things, in order to make the baseball team, the little tike will have to grow up a bit and practice, learning how to accurately throw and catch a ball. The young red-tail, in a few weeks in summer, must learn how to hone her instinctive hunting desires into refined killing techniques. A few red-tails learn these skills every year and later become adults. Most fledged eyasses, however, fail to learn the killing lessons and don't get a contract for living after August or September. They just starve.

Can you see that the behaviors of daily survival -- hunting stealth and killing -- are completely at odds with nesting, incubating, and eyass feeding ones? If I were to toss a young chicken hatchling beneath my falconry red-tail, she would kill and eat it in a second. But on the nest, a sitting adult does not consume the new little eyass. But it's no different from a wondering duckling that has just hatched. The hawk will kill a young duck instantly. Location is everything.

It's interesting to watch how red-tails change -- by instinct -- their behaviors around and on the nest. Other raptors do this too. Within a few hundred meters or so of the nest, red-tails' hunting desires are somehow turned off. By instinct, they are prohibited from killing anything near the nest. This keeps them from grabbing one of their own eyasses for a quick snack. While on the nest, they often fold under their sharp talons so as not to puncture the egg.

We falconers are always astonished to watch a red-tail (or peregrine, or any other raptor) feed their eyasses. It's against their everyday common behaviors, and it's all controlled by sex hormones. In the spring and summer, with expanding day lengths, the birds' aggressive behaviors at the nest are turned off. If a red-tail could think while tending a cute little eyass (she can't), I think she would be asking, "Why am I doing this? This little thing moves around and is really a nice meal. Why can't I just reach out and kill the thing and eat it?"

She can't because her reproductive hormones have kicked in a whole new set of restrictive behaviors, none of which result from thoughtful decision making or other cerebral activity. The hawk is just going through the motions. Don't even think about killing anything within a few hundred meters of the nest. Don't grab anything that moves. Drop little pieces of meat down the open throat of the bobbing eyass. Sit on it and keep it warm.
In summary, the otherwise "emotional" behaviors or thoughts of the adults are really mechanistic, instinctive behaviors. If there is a round white object there, sit on it and roll it around a few times every day. The 927 pair are still following these hormonally-driven behavioral prompts. Not until they get tired of it, only when it gets very old, will they stop. They are clueless about what they are doing. They are not waiting for the eggs to hatch. They are merely sitting on them because they are programed to do so, period. There is neither joy or lament, just instinctive behaviors that are so contrary to what they do "normally."

Normally, red-tails sit around and think about how they can easily capture another animal. Here, they calculate and plot. They learn what hunting methods work and don't work, which is one of the great stories about red-tails in Central Park. No falconer or raptor biologist would have predicted that red-tails could have so successfully inhabited Central Park because the hunting techniques they learn and use in the wild shouldn't (and wouldn't) work in the city. But these birds have thoughtfully learned to successfully hunt and kill, and we therefore get to experience them in the heart of one of the world's great cities.

Red-tails are thoughtful and emotional in hunting and killing -- in daily life. They are not so in nesting. To be successful nesters, they must turn off their normal emotions and go into a behaviorally restrained, leave-it-live mode of life. It's the lack of "emotion" that allows the species to breed each year.

--John A. Blakeman

Thursday, May 04, 2006

Donna has a blog

We've been enjoying Donna Browne's reports for more than a year. Now she has a blog of her own. Here's the address:

Wednesday, May 03, 2006

They're here at last

Hooded Warbler - 4/29/04
Photo by Cal Vornberger
Monday was the absolutely the worst first of May any of us can remember. There wasn't a bird in sight, not a warbler, not a vireo, not a flycatcher...nothing. All right, maybe there were a few robins.

Everybody knew why there were no birds. The migrants wait for southwest winds to speed them on their way. On Monday, and for many days before, the winds were from the northeast. So the northward-bound birds waited where they were, North Carolina or Maryland or New Jersey, for the winds to change.

Tuesday was a bit better, but nothing to write home about. Today the bottleneck unclogged. . Of the following list, from the New York City Bird Report, the Early Birders saw quite a few, notably, the Vesper Sparrow [a rare CP visitor] and the stunning little Hooded Warbler.

Best of all, the park was alive with the sound of ... thrushes, thrashers, catbirds and lots of others, all singing. Including the Hooded Warbler. It was singing persistantly as it made its way around the Ramble: Wee-o-wee-o-wee-tee-o.

Central Park Bird Report for May 3, 2006

Double-crested Cormorant*
Great Egret*
Green Heron
Black-crowned Night-Heron
Canada Goose
Red-tailed Hawk
American Kestrel
Spotted Sandpiper
Ring-billed Gull
Herring Gull
Great Black-backed Gull
Rock Pigeon
Mourning Dove
Black-billed Cuckoo* (YD)
Chimney Swift
Red-bellied Woodpecker*
Downy Woodpecker*
Northern Flicker*
Eastern Kingbird
White-eyed Vireo*
Blue-headed Vireo*
Warbling Vireo*
Red-eyed Vireo*
Blue Jay
American Crow
Tree Swallow
Northern Rough-winged Swallow
Barn Swallow
Tufted Titmouse*
Red-breasted Nuthatch* (D)
White-breasted Nuthatch
House Wren*
Ruby-crowned Kinglet
Blue-gray Gnatcatcher
Hermit Thrush*
Wood Thrush*
American Robin
Gray Catbird*
Northern Mockingbird
Brown Thrasher*
European Starling
Cedar Waxwing
Blue-winged Warbler*
Nashville Warbler*
Northern Parula*
Yellow Warbler*
Magnolia Warbler* (YD)
Black-throated Blue Warbler*
Yellow-rumped Warbler*
Black-throated Green Warbler*
Pine Warbler* (D)
Prairie Warbler*
Palm Warbler*
Black-and-white Warbler*
American Redstart*
Northern Waterthrush*
Louisiana Waterthrush* (D)
Common Yellowthroat*
Hooded Warbler* (YD)
Wilson's Warbler* (YD)
Scarlet Tanager*
Eastern Towhee*
Chipping Sparrow*
Field Sparrow* (D)
Vesper Sparrow* (D)
Savannah Sparrow* (D)
Song Sparrow*
Swamp Sparrow*
White-throated Sparrow*
White-crowned Sparrow*
Northern Cardinal
Rose-breasted Grosbeak*
Indigo Bunting*
Red-winged Blackbird
Common Grackle
Brown-headed Cowbird
Orchard Oriole
Baltimore Oriole*
House Finch
American Goldfinch*
House Sparrow

84 species (excluding hybrids and reported with full confidence)

[YD means the first sighting for the year.. D = a notable bird, though not the first sighting. An asterisk means that if you go to the website, click on Central Park, and click onToday, you'll get additional information about who saw the bird and where.]

Leave the nest alone

Eastern Screech Owl at the Point, yawning 4/29/06 [Could be the female from the West Drive cavity]
Photo by Cal Vornberger

A last word about PM and Lola's nest failure from Marilyn Konefal [a visitor to NYC but she didn't say where she's from] :

Hi Marie.

I've read the correspondence on your web site and I'd like to
add a few words.

I visited NYC on Saturday with my husband. We were disappointed along with all the others looking to see feeding behaviors by this time. But we did see something wonderful - Pale Male and Lola.

I believe, like others, that we should look to learn from the past - because if we don't, history will repeat itself.

It certainly looks like the eggs are not going to hatch. Past experience shows 2 seasons went by before there was a successful nesting season. This is the 2nd year. So there should not be too much cause for alarm. There is talk about obtaining the eggs to see if what happened can be deduced through examination. You know that the temptation to mess around with the nest itself will be very great (human nature) to see how thick the nest is, what kind of lining there is, if the spikes pierced the inner bowl, etc. Each time the nest is disturbed it sets the whole process back. Who knows if this activity will push a successful year back yet another 2 years?!

Leave the nest alone. Sure, if another 2 years goes by without any fledglings, then perhaps that would be the proper time to research what's going on. But not now.

Tuesday, May 02, 2006

Blakeman's response

Yesterday I posted Steve Watson's letter responding to John Blakeman's previous posting. Blakeman's has written a response to the response which follows an item I find relevant to the discussion, though it is about a mammal, not a bird. It is from Cal Vornberger's blog for 4/24/06 on his website

Mother Squirrel Tries to Revive Baby

I went to the park yesterday after the rain had stopped. While walking in the Ravine I noticed a squirrel running across the path with a baby in its mouth.

It wasn't until I got to the Meer and took a series of photos of this mother squirrel trying to revive her baby that I realized what happened. The heavy rains must have flooded squirrel nests and washed some of the babies out of the nest.

The poor mother squirrel tried everything to revive her baby: she licked and pulled at its paws; she lifted it up and shook it; she rolled it over on its back and nuzzled its belly. Finally she ran off with it across the park drive. I didn't see any movement in the baby squirrel but looking back over my photos I did notice its eyes open in some photos and closed in others. There may have been some faint spark of life left in this baby and the mother squirrel was doing everything she could to bring her baby back to life.

Here is John Blakeman's response to Steve Watson's letter:

Steve Watson would prefer to leave open the possibility that red-tails that have lost eggs or eyasses might have some sort of emotional response. In order to determine that they don’t, he states, “One would have [to] conduct some sort of controlled experiment (and be able to measure emotion somehow) in order to prove such a statement...and that would be a very difficult thing to do.”
He’s correct. To scientifically “prove” the emotional responses of red-tails with failed nests, extensive and replicated quantitative behavioral tests would have to be conducted. This has not been done, and because of the difficulties in arranging such a study, it’s not likely ever to happen.
On what basis, then do I so pedantically state that red-tails don’t have emotional feelings of loss? How can I know that Pale Male and the other Central Park red-tails aren’t lamenting the failure of their eggs to hatch?
I am thoroughly confident in my contentions, based upon 38 years of detailed and extensive work with Buteo jamaicensis, the red-tailed hawk. I have a collection of experiences with the species that very few others have. Like many, I’ve spent hundreds of hours in field studies. I know the bird from the viewpoint of binoculars and spotting scopes, from Alaska, through the West, and across the Midwest. While others search appropriately and rewardingly across the landscape to discover, see, and study as many bird species as possible, my studies and interests have been very narrow and concentrated almost exclusively on B. jamaicensis.
From my field studies, after observing hundreds of red-tail pairs, I’ve never seen any behavior that suggests sorrow, lamentation, or other typically mammalian or human feelings of loss.
But how might I (or any other researcher) even know what such a behavior might be? Discovery and description of such could only come from extensive contact with the species throughout its normal life span and behaviors. Since I have conducted red-tail breeding trials for several years, I’ve watched all red-tail breeding behaviors as closely as possible.
In these trials, I know exactly how adults react to egg laying, removal of an egg, loss of an egg, and as we’ve seen this year, how the birds react when the eggs don’t hatch. There is no emotion, just ritualistic, instinct-driven behaviors. Unlike us, the birds don’t have a calendar and have no idea when the eggs are to hatch. Yes, they get excited and begin to look into the nest bowl when they feel the eggs pipping and hear the first vocal utterances. But when none of this happens, the birds just continue to incubate.
How could I know the hawk’s “emotion?” How would an equestrian know a horse’s emotion. I believe the angle of the ears is extremely revelatory. People who train and ride horses would be expected to know a horse’s emotional state by merely looking at it. To me, it’s just a horse. I can’t “read” a horse. But I can read a red-tail. That derives from my extensive falconry experiences with the hawk. After spending hundreds of hours in training and hunting with a red-tail on my fist, I can read her at a glance. I know exactly when she’s angry, when she’s lazy, when she’s attentive, when she’s wary, when she’s afraid, and when she wants to attack. Unlike others, I have had the privilege to watch her in extreme ecstasy as she kills and eats a tasty rabbit. She has a behavioral aura and posture never seen at other times.
On the other hand, I’ve taken both eggs and an eyass from captive breeding pairs, and watched how they behaved after their “loss.” Nothing. The birds just sit around and go about their normal activities. They don’t go off food, they don’t sit and sulk, they don’t become aggressive or angry. Nothing. Once the egg or eyass is no longer seen, life resumes. From habit, the birds will come over to the nest and look into it with some food to feed the missing eyass. But in a moment or two, it is either left to dry on the nest, or the adults just eat it themselves.
Central Park hawkwatchers are encouraged to construct their own, personal explanations of what they see. These experiences have been the basis for mine.
--John A. Blakeman

All is not lost

Bill Trankle of Indianapolis, a frequent correspondent of this website, writes:

Just when I thought NYC had completely struck out I see on the falcon cam at 55 Water St. that the peregrines have finally hatched-- two chicks, so far. I'm a bit surprised that they did because they were incubating at the same time that our pair in Indy were, and our Indy falcons have had chicks for two weeks! I'd assumed the NYC eggs were dead, but fortunately not! It may not be Pale Male, but it's going to be entertaining anyway.

Monday, May 01, 2006

A different view on animals' emotions

Warbling Vireo on Saturday, 4/29/06
Photo by Bruce Yolton

Steve Watson, a scientist [though not a biologist,] and a long-time correspondent of this website, [remember Lili and Dash, his beautiful but ill-fated kestrels he was monitoring at his home in California?]writes in to respectfully disagree with John Blakeman's "Let's get real" letter. I posted it here two days ago. Here's what Steve has to say:

People may be doing a bit of anthropomorphizing (with which I disagree) and I'm certainly no biologist, but John Blakeman's statements like "that's the only way animals without complex cerebral cortices can act" are perhaps a bit too pat. I said it before, and I'll say it again...we can no more know if a bird feels loss or sorrow than we can another person, because we can't get into their brain. We can make knowledgeable assumptions, but to state unequivocally that they "can't cerebrally contemplate the loss", I think, goes too far. I think that most of the biologists I've met would say something like "we don't currently believe that [some species] have emotions such as loss or sorrow" and state why, but they would never state it in such absolute terms.

I'm not arguing that these birds DO feel a sense of loss, just that telling people to "get real" and that Pale Male and the others "can't emote like we do" came across as a bit pedantic...and I normally really *like* what John writes! :) I actually doubt that they *do* feel any sense of loss at a failed clutch, but who are we to say that they don't? One would have conduct some sort of controlled experiment (and be able to measure emotion somehow) in order to prove such a statement...and that would be a very difficult thing to do.

There are plenty of instances of animals exhibiting sorrow/loss/grief at the loss of an infant offspring, so it's not inconceivable to me that a bird wouldn't feel *some* sense of loss at a failed clutch. I think it would be interesting for your readers to discuss the harsh aspects of nature and perhaps the rates of clutch failure and infant mortality in wild raptors, as well as how one would test an hypothesis relating to whether they have such feelings as loss or sorrow.