Saturday, July 14, 2007

Pale Male is fine

I hadn't seen Lincoln's posting today until I started getting frantic e-mail. As far as I know everything is fine. I hope Lincoln posts another report soon.

Friday, July 13, 2007

Birds don't dig Golden Oldies

Song Sparrow []Melospiza melodia]

Chris Karatnytsky sent in this fascinating study about birds' song. The journalist is obviously not a birdwatcher since she or he doesn't mention what species of sparrow is involved in this study. But I'm assuming it's the Song Sparrow, the prettiest singer of the lot, in my opinion.:

NEW SONGS ARE FOR THE BIRDS
Sparrows Don't Dig Oldies, Research Shows

Birds, new research has found, aren't sentimental when it comes to music. Songs from just 30 years ago are received with equanimity, while newer tunes make the males aggressive and the females randy.

The Who. The Police. The Spice Girls. This year, it seems the only band not embarking on a reunion tour is the Byrds. According to new research written up in the journal Evolution, that's no accident. Turns out, an evening of oldies wouldn't go down nearly so well among our feathered friends.

Elizabeth Derryberry, a biologist at Duke University in North Carolina, compared recordings of sparrow hits from 1979 to those of 2003 and found that the newer songs have a much slower rhythm and dip further down into the lower registers. And upon playing the different versions to hip, modern-day sparrows in a variety of areas, she found that today's birds are much more into current chart hits than those of 30 years ago.

The 20 males that heard Derryberry's two recordings reacted much more aggressively to the new tunes, ready to defend their territory against the crooning interloper. And the chicks? They responded by becoming more open to sexual advances when the new music was played. The oldies didn't turn them on at all.

"I'm not saying a female bird won't respond to an old song, but not as much as she would to the newer version," Derryberry told the newspaper the Daily Telegraph. "They regard the old songs as not as interesting, not as good as the new ones."

The scientist, who carried out her experiment near Yosemite National Park in California, has been studying bird song recordings made over the last three decades to determine how tunes evolve and whether the changes have to do with mate selection or habitat. The results of her test, she says, show that stylistic differences develop rather quickly, affecting mating and the passing on of genetic information. It could even provide clues to how new species develop.

Regional dialects among songbirds have long been recognized, as has the fact that birds -- like humans -- respond more strongly to local songs than to those from abroad. However scientists were previously less knowledgeable about changes over time.

Thursday, July 12, 2007

Manhattanhenge addendum --from Neil deGrasse Tyson

Neil deGrasse Tyson of the Department of Astrophysics & Director, Hayden Planetarium at the American Museum of Natural History sends this communication:

As you may know from my previous correspondence, Manhattanhenge occurs twice per year: The first near the Memorial Day Holiday. And the second near Baseball's All Star break.

My calculations show that second one occurs tomorrow, Friday, July 13, 2007. Event begins: 8:20PM. Sunset 8:27. At a cross-street near you.

See details here, which includes the content of my previous correspondence:
http://haydenplanetarium.org/resources/starstruck/manhattanhenge/

Note that, in principle, any city with a grid can identify days where the setting Sun aligns with their streets. But a closer look at such cities shows them to be less than ideal for this purpose. Beyond the grid you need a clear view to the horizon, as we have over New Jersey. And tall buildings that line the streets create a kind of brick and steel canyon to frame the setting Sun, creating a striking photographic opportunity.

True, some municipalities have named streets after the Sun, like Sunrise Highway on Long Island and the Sunset Strip in Los Angeles. But these roads are not perfectly straight. And the few times per year when the Sun aligns with one of their stretches of road, all you get is stalled traffic as drivers are temporarily blinded by the glare.

So I am almost inclined to declare that Manhattanhenge is a unique urban phenomenon in the world, if not the universe. But I still have a few more cities to check on.

As always, keep looking up -- except in this case, when you will be looking to the horizon.

Wednesday, July 11, 2007

Nope,not too cute--just cute enough


Bob Levy sent in the photo above on 7/9/07 and wrote:

I feel it’s my responsibility to warn you that this photo may produce a cuteness overload in your sensory system. View it (or the real thing at Turtle Pond) at your own risk.

About the MBTA

Just in case some of you are unclear about the Migratory Bird Treaty Act, [which played an important role in the Pale Male story, as readers of my book may remember] website reader Liz Pomper sends in the following clarification:

Hi Marie,

You may want to clarify John Blakeman's recent letter, which implies that only raptors have federal protection. In fact, ALL migratory birds are protected under the Migratory Bird Treaty Act, which prohibits one "to pursue, hunt, take, capture, kill, attempt to take, capture or kill, possess, offer for sale, sell, offer to purchase, purchase, deliver for shipment, ship, cause to be shipped, deliver for transportation, transport, cause to be transported, carry, or cause to be carried by any means whatever, receive for shipment, transportation or carriage, or export, at any time, or in any manner, any migratory bird, included in the terms of this Convention . . . for the protection of migratory birds . . . or any part, nest, or egg of any such bird." (http://www.fws.gov/laws/laws_digest//migtrea.html)

That means that it is ILLEGAL under U.S. law to even possess a feather of any migratory bird, although clearly this provision isn't enforced too heavily. I would suspect someone using feathers in artwork, though, would run into some trouble.

A list of protected species can be found here: http://www.fws.gov/migratorybirds/intrnltr/mbta/mbtintro.html

Successfully advocating for the passage of the Migratory Bird Treaty Act was one of the earliest accomplishments of the National Audubon Society (then the National Association of Audubon Societies).

Liz

Tuesday, July 10, 2007

.TOMORROW

Website reader Mitchell Nusbaum writes in to remind New Yorkers that if you missed Manhattanhenge last month you'll have another chance to see this phenomenon at sunset on July 11. That's tomorrow

Hawks vs Bluebirds: a different point of view

the European Starling --an ever-present argument against laissez-faire

Chris Lyons, who last wrote on this page about the orange chest color of redtail fledglings, has a different and compelling point to make about interfering with nature

Marie,

I read your response to the person who is upset over 'his' bluebirds and squirrels being captured and eaten, allegedly by a Red-Tailed Hawk. I agree with the general spirit of your response, but not with the specific advice you give. Human beings interfere with nature simply by existing in the manner we currently do, and in the numbers we currently do.

To name one specific example: by reducing the amount of suitable nesting habitat for the Eastern Bluebird, and also introducing hole-nesting exotics like the House Sparrow and Eurasian Starling to North America, we have made it extremely difficult for Bluebirds to successfully reproduce, regardless of hawk predation (which I do not believe is considered a major threat to Bluebird populations overall). Bluebirds have dealt with native predators long before we arrived, but without the carefully maintained 'Bluebird Trails', maintained by groups like the North American Bluebird Society, http://www.nabluebirdsociety.org/ their numbers could never have rebounded, and their beauty and music would be lost to us, by our own doing. Ironically, we first increased their numbers, by planting orchards that served as ideal habitat for them. We grew accustomed to having them in our gardens and backyards, came to love their beauty--then became increasingly disturbed as we saw them usurped.

The principle is very simple--we have reduced the number of natural tree cavities, and increased the number of competitors for those cavities.. Bluebird boxes even the odds a bit, by reducing the number of potential nest competitors, and placing the Bluebirds near people who will monitor them, and in some cases, intervene on their behalf. This is unquestionably a form of interfering with nature--but only in response to much more severe disruptions to the natural order, created by the workings of our civilization. It may be a doomed effort, but it is no more 'unnatural' than putting up boxes for urban-nesting Peregrine falcons, who are rarely able to successfully nest on human structures without our assistance. Red-Tails, of course, are quite able to nest successfully without our help--but we still give our help, now that we have decided they are majestic examplars of freedom, instead of heartless chicken killers, and exterminators of friendly songbirds. But they are what they always have been, regardless of the emotional filters we place around them.

In a sense, people angry about hawks preying on animals they feed and house in their backyards, purely for the joy of seeing those animals, are the successors to the small poultry farmers who shot any hawk they saw, in order to prevent their barnyards from being raided. In so doing, they often did more harm than good, even in relation to their own endeavours. But really, what bothered them was that they felt their property was being destroyed--they were so angry over the 'murder' of birds they fully intended to kill themselves anytime they wanted a chicken dinner. It was simply assumed that man had dominion over all of nature, and that we had both the right and the duty to manipulate it to our liking. We haven't really surrendered that notion, when you get right down to it.

Perhaps this man who wrote you hasn't done a good enough job following the guidelines set by the groups seeking to encourage Bluebird nesting. My father has Bluebird boxes on his property in South Carolina, which he maintains according to those guidelines. He also has plenty of hawks around. He hasn't noticed any particular problem with raptor predation--the main problem is that a lot of other birds like to use these boxes, such as Carolina Chickadees and House Wrens. Tree Swallows quickly find them in our area, though they are also quite capable of finding natural nest cavities.

I dislike the notion that it's possible for us to never interfere with nature, and the lives of animals. This is one of our most arrogant illusions, based on our image of ourselves as benevolent creatures. We can only pick and choose how we interfere, try to limit the amount of damage we do, and compensate for it in some instances--in so doing, we are inevitably going to make mistakes.

In a truly wild setting, where the old system of checks and balances is intact, we can usually sit back and let nature take its course, but there are increasingly few places where this holds true, and even in the deepest of wilderness areas, we are often intervening on behalf of one endangered species or another--all of which are endangered because of the way we have irreparably changed the world we live in, and not usually for the better. We intervene every time we try to put out a forest fire. We intervene every time we preserve an old growth forest. And we intervene if we do none of those things. We do not live in harmony with nature. If we wish to do so, we will have to give up all our modern conveniences, and go back to living the way we did in the stone age--and even then, there's some evidence we hastened the end of many species. As we may hasten our own end, if we don't watch out.

It would be nice if there was some immaculately cut-and-dried formula of moral righteousness we could follow here, but it simply doesn't exist. We have to make it up as we go along. With regards to our fellow creatures (and ourselves), we are never impartial--we always play favorites. We can and should try to allow for that, but I don't believe it's a trait we'll ever rid ourselves of. Anymore than we can rid ourselves of the tendency to accuse others of the same things we are guilty of ourselves.


Monday, July 09, 2007

Blakeman responds and so do many others, with a small sampling included

John Blakeman sent in a quick response to my recent question:

Marie,
I'm sorry for somehow conveying the thought that marauding Cooper's hawks (or any others) should be killed. I didn't intend any such thoughts.
Let's make this very clear. All raptor species are strictly protected by both state and federal laws. No one is permitted to trap or kill a wild hawk, period.
In fact, it's illegal to even pick up a hawk feather found on the ground. That's an illegal possession of a protected bird part. Let's get this straight. Hawks and all raptors are thoroughly protected by state and federal laws. The days when citizens could arbitrarily shoot a hawk out of the sky, or put up a pole trap and snap a pair of metal jaws on a hawk's feet are ancient matters from the last century.
Yes, the matter involves the "control" of nature. The feeding of birds at feeding stations is about as unnatural as can be. But that's a personal matter, and it's not illegal. There is evidence that mourning doves and cardinals have proliferated in northern states because of bird feeding. In Ohio, cardinals were seldom if ever seen here in the winters of the 19th century. Bird feeding may have changed that.
Rather frequently I get a phone call from some local resident asking if I'm the "hawk man." The person wants to know what can be done about a Cooper's hawk that is killing birds around the caller's feeding station. I courteously reply that nothing can be done other than to stop feeding the birds, allowing them to disperse. But I always thank the caller for feeding all of the birds, including the local Cooper's hawk.
It's curious how Cooper's hawks were once a universally admired species, back 30 years ago when they were only rural and infrequent. Today, a great number of urban bird feeders, who have personally witnessed the hawk's depredations, no longer admire the species.
Nevertheless, the hawk is totally protected, as it should be.

John A. Blakeman

And here are two of the many responses [all of the same persuasion as the ones below] that came in about the "I want to kill that redtail" person:

Bill Trankle of Indianapolis, IN writes:
The Coopers hawk(s) who patrol my yard keep things interesting to be sure, and while I have noted a drastically decreased utilization of my feeders (especially in the afternoons) I cannot say I hate them. It's all part of a balance out of which humans long ago fell, leading to our distaste for that which we cannot dictate.

Robin (from cyberspace) writes:
I have my bird feeders hanging in a fully grown tree which helps to prevent a stoop and kill from above (even in seasons when the tree is bare) and the feeder birds are very aware of their surroundings and react in the blink of an eye to potential threats. 15 years ago I planted a dozen arbor vitae around my small yard. They are huge now. I have my birdbaths set right next to the dense big evergreens. I have dense ivy climbing up the supports to my patio and the songbirds build their nests deep in the ivy (usually ignoring the many bird houses I have hanging nearby, under the patio roof).

At the slightest disturbance - someone walking down the sidewalk, a crow overhead, a cell phone ringing - the birds flee instantly to the dense natural shelters.

I think the bluebird writer might look for ways to naturally protect the bluebirds instead of doing the typically human thing and killing things that get in the way of our intentions.

Sunday, July 08, 2007

Blakeman raises a question, I ask a question back, and Jan sticks up for me


In response to yesterday's letter by D.B. who wants to kill a redtail eating "his" bluebirds, John Blakeman, our Ohio hawk expert, writes:

Marie,
There is a very good possibility -- baring the discovery of a tail that is red on the bird -- that the villain in question was a Cooper’s hawk, a species much more capable (and likely) to capture bluebirds.
Bluebirds, especially those just fledged, are scrumptious, easy pluckings for a neighborhood Cooper’s hawk.
I just don't think a red-tailed hawk can take anything but an incidental bluebird, one that is somehow handicapped, or a still-flightless fledgling. A Cooper’s hawk, however, can take both fledgling and adult bluebirds with frightening ease.
And (if the Cooper’s is the real culprit) this raises a very interesting development. Here in Ohio, and elsewhere in the Midwest and East, where wooded habitat abounds, American kestrel populations have markedly declined in the last decade. The species is still not rare. But even casual kestrel watchers have noted their reduced numbers in recent years.
Here in my area, to reverse this decline, a Boy Scout, for his Eagle Scout Project, erected about 10 kestrel nest boxes, all on tall utility poles. I oversaw a similar project 30 years ago here, and within two years virtually every box had a nesting kestrel pair. This year, with the new boxes, in prime kestrel habitat, not a single one was occupied.
In fact, I see only a scattered, low number of perched kestrels hunting from roadside utility lines. The species is decidedly declining, while virtually all other raptors are stable or increasing. How so?
It’s becoming ever more obvious that as Cooper’s hawk numbers have increased, along with their recent invasion into small cities and suburbs, kestrel numbers have declined. An experienced adult kestrel can usually avoid a Cooper’s hawk attack. But kestrels right out of the nest cavity don't fly well for several weeks. As they flap around trying to learn how to fly with agility, they give themselves away to any marauding Cooper’s.
So, kestrel reproduction in areas with increased Cooper’s hawk has been greatly suppressed by these bird-eating accipiters.
Cooper’s hawks eat almost nothing but birds, and they've recently learned that large, vulnerable concentrations of small birds can be found and easily preyed upon in numerous backyards, at urban and suburban bird feeders.
Cooper’s hawks are proliferating so successfully that I believe that it’s only a matter of time before bird feeders begin to notice reduced populations of dickey birds at the feeders. It’s a glorious time for Cooper’s hawks, who have now learned to come into cities that have backyard bird feeders.
This may have been the case with the unfortunate bluebirds that prompted this note.

John Blakeman

My question in return:
Dear John, Does your letter mean that if the hawk eating R.B.'s bluebirds proves to be a Cooper's Hawk, then it would be OK for the guy to try to trap or kill it, because Cooper's Hawks are proliferating like mad, killing kestrels, etc.? Somehow you leave this question hanging. Though the question of the hawk's correct species is an interesting one, it obscures the larger question of whether R.B's desire to kill the marauding hawk, whether it's a redtail or a Cooper's, is justified.
I tend to agree with another correspondent, Jan Lipert, who writes:

You tell 'em, Marie! It drives me crazy when people want to isolate one particular element from nature and plop it into their yards -- and then get furious when nature takes its course. It amazes me that people try to orchestrate their back yards the way they do their own lives. Inside, humans may have their way, but outside, Nature Rules!
Jan Lipert