Friday, February 08, 2008

John Blakeman Begins Eagle Nest Watch

Photograph and Graphics-John Blakeman
John Blakeman has been restoring a huge long grass prairie for NASA the past few years and today he mentioned an Eagle's nest on the site in an email. Needless to say, I jumped on it and said, "Give us more!"
Here's his return email and I'm hoping he'll keep us posted as things progress for the Plum Brook Bald Eagles!

Of curious interest to those who will begin 2008 observations of the 927 Red-tailed Hawk pair Pale Male and Lola, might be a somewhat parallel “watch” I’ll be doing from time to time here in northern Ohio.

Instead of watching a pair of Red-tails attempt to bring off a brood of new eyasses, I’ve got my eyes on a local Bald Eagle’s nest, which was blown out of the tree two weeks ago, but is now being re-built.

The nest is at NASA’s Plum Brook Station, a 6400-acre space science research facility just down the road from my residence. Plum Brook Station (PBS) in WWII was the Plum Brook Ordinance Works, where a billion pounds of TNT and other high-explosives were manufactured from 1941 through 1945. In the 1950s, NASA built one of the world’s largest nuclear research reactors, which made giant “fluxes” of neutrons, to test materials that then were to be used eventually in nuclear-powered spacecraft. The reactor was closed in 1973, and is now being decommissioned.

Also at PBS is the world’s largest space environment center, a giant dome 120 tall and 120 ft in diameter. Inside, all air can be pumped out, creating a vacuum equivalent to 90 miles up. The chamber can be cooled to space temperatures by circulating liquid nitrogen through heat-absorbing pipes on one wall of the chamber. On the opposite wall can be placed a giant mass of infra-red emitting light bulbs, which recreate the thermal effects of the intense sunlight in space. Except for the presence of gravity, a space environment can be accurately created in which to test, on earth, all sorts of spacecraft. Pretty awesome, actually. There are some other remarkable space engineering facilities at PBS, including a lab that produces the coldest, densest liquid hydrogen, the “K-Site Facility.”

And right behind the K-Site building is the PBS Bald Eagle nest.

I am an Environmental Specialist at PBS, responsible for planning and conducting massive landscape burns to restore up to 2500 acres of native tallgrass prairie. We are in the planning process for the 2008 prairie burns at PBS, and I therefore have the opportunity get some viewing time near the nest. For obvious safety and security reasons, the public is not allowed inside the Station. I have a rare opportunity this year to closely follow the nesting activities of this pair of eagles.

If you or your readers are interested, I’ll try to post periodic updates.

For now, here’s the background on the PBS eagles – which actually now typically represent a veritable multitude of new Bald Eagle nests and territories in Ohio. As elsewhere, Bald Eagles in Ohio have exploded in number in the last decade or so. In the early 80s, just three nests remained in all of Ohio, one of which happened to be a quarter mile behind my residence at the time, out in a big cottonwood tree in the East Bay of Sandusky Bay, off Lake Erie near Sandusky. At the time, it was presumed that in a year or so, Bald Eagles would be extirpated from the state.

But because DDT was made illegal in the mid-70s, eagle reproduction increased slightly in the mid-80s. By the 90s, the preferred Lake Erie shoreline was saturated with more than two dozen new nests. New, maturing adults had to move inland, which they did. The PBS pair is an example of that new population trend.

In January, the Ohio Division of Wildlife asks raptor afficionados to report every eagle they see for a period of time in January. This year, over 600 winter Bald Eagles were seen in Ohio, a remarkable record.

Just as Pale Male colonized and used a new, non-typical Red-tailed Hawk territory – Central Park – many of the Ohio Eagles have taken up residence in inland areas, such as Plum Brook Station. Typically, Bald Eagles build nests in trees over rivers and lake shores. Those habitats, at least in northern Ohio, are all filled. So in desperation, new nests have been built at non-watery inland sites. And remarkably, these nests have been generally as successful as the lakeside ones.

The inland eagles aren’t eating as many fish, which is their normal diet, because of their new locations. Just as Pale Male isn’t eating any voles, the food typical rural Red-tails thrive on. PM is eating rats and pigeons, which are seldom taken in the countryside. The PBS Bald Eagles are eating road kill deer and capturing young woodchucks and other mammals, things a real “fish eagle” wouldn’t be expected to hunt and consume. Surely, Bald Eagles and Red-tailed hawks are remarkably intelligent and adaptable species.

The PBS eagles have been here several years, producing eaglets. But last year, the pair simply failed to work on the nest or lay eggs. Bald Eagles are famous for this. After producing eaglets for a few years, a pair typically takes a year off, perhaps to physiologically rest. Everyone at PBS, from the rocket scientists to the maintenance technicians, were very glad to see the eagles back at the nest in January this year.

Then, 60 and 70 mph storm winds two weeks ago blew the old nest right out of the tree. Everyone was distraught, but I reassured them that the birds would get a nest back up in no time. And that they did, as the photo shows.

Today (Friday, 8 Feb) I was able to watch the nest activities for only about a half hour, late in the afternoon. In that time, five flights brought new sticks to the nest, four from the smaller male, and one from the giant female. Just as Pale Male and Lola insert their sticks into their nest, these eagles diligently thrust the sticks into the accumulated pile.

One notable thing. Pale Male and Lola actually bring twigs to the nest. Bald eagles bring real sticks. Most of these today were about 2-ft long, and as thick as my thumb.

It was a typical dark, cloudy, mid-winter day, with no wind. As I sat in my car about 200 yards from the nest, I heard for the first time the remarkable vocalizations of the eagles as they decidedly “talked” to each other while working on the nest. The sounds, at times, emulated the cry of the Red-tail, but with a slightly gutteral, even murmuring quality. In the winter quiet, it was a primal, even wilderness sound. I was honored to be able to hear them.

The usual territorial scream or cry of the Bald Eagle is disappointingly weak, high-pitched, even feeble. It does not match the bird’s size and majesty, unlike the piercing, quintessential, descending cry of the Red-tailed Hawk. I hope everyone in Central Park and along Fifth Ave gets to hear that iconic sound. It’s Pure Nature.

I had hoped to see the birds carrying new lining material to the nest. But they aren’t ready for that yet. The nest is only (yes, only) about five feet across the top. I gauged that by noting that when the female, who is about 3 ft from bill to tail in length, sat horizontally on the nest, a good foot remained on each end of her.

I’ll watch to see how this turns out. The nest may end up twice its present size. Fortunately, there appears to be a clear aspect to the nest from the road, through which we should be able to watch incubation and the young eaglets, un-obscured by leaves and twigs.

So, as everyone gets to resume watching PM and Lola from The Bench this year – now with the real prospect of new eyasses, sans the pigeon spikes – I’ll be doing the same thing at Plum Brook Station, watching for an eaglet or two. The regal nobility of both the NYC Red-tails and the Plum Brook Station Bald Eagles should provide some wonderful experiences, things so needed in our lives that are otherwise so muddied by the murk of normal day to day living.

John Blakeman
(To access the most recent posts, click on Palemaleirregulars at the top of the page.)

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