A Visit to Wacker!

Wacker Peregrine Falcon (adult female)Today, Mary and I had an appointment to visit the south Wacker pair, who we were both hoping would be the same pair from last year – Etienne and Rahn. We left the museum at 8:30am and arrived at the Wacker building at 9am.

By 9:15am, we were up on the top of the building and ready to open the door to the nest ledge. “Ready?” Mary asked.

She opened the door and looked first south, then north. Last year, the pair nested in the south nest box. This year, they have nested in the north nest box. One of the adults glared at us from the nest box. The other was nowhere to be found. As I snapped pictures, Mary considered the situation.

“See the way she’s sitting? Really low, her wings nice and flared out? That means she’s probably sitting on eggs, so her chicks haven’t hatched yet. She’d be sitting up higher and moving around a lot more if there were chicks under there.”

She did sit very, very still. In fact, as much as we wanted her to get up for a minute so we could get a look at her bands, she didn’t once oblige.

“Man,” I said. “She looks gorgeous. I hope it is Rahn, but I can’t tell. And where the heck is Etienne?”

Mary scanned the sky, but all was quiet.

“I don’t know,” she said. “But, why don’t you roll out a bit and try to get the camera at an angle where we can see a bit more of the floor of the nest.”

Respiration AdaptationI did so and was just setting up when I heard a soft *pffffffft* behind me.

“He’s here, isn’t he?” I asked, not moving.

“Yep! He’s right behind you. Go ahead and roll back in.”

I did so, real easy, and turned to get my first look at Etienne. He was sitting in the exact pose as last year with that same expression. What a stealthy little beauty.

I say ‘little’, because now that I’ve had some experience with peregrines, it’s pretty obvious that Etienne is a small guy, but perfectly proportioned. Mary said she thought he was the prettiest peregrine in the city and cooed over him appropriately.

I snapped a lot of pictures of handsome Etienne before we closed the door and meandered on to our next destination. In the picture above, you can get a really nice look at his nostril structure. On the Fresno Chaffee Zoo site, they have an interesting thing to say about that:

“The swept-back wings are the most striking feature of a flying falcon. Falcons are known for their high speed flight, and the Peregrine is thought to be the fastest bird, accurately clocked at 90 meters per second. A contender is the Prairie Falcon.”

“Incidentally, in the making of airplanes, especially jets, humans came onto a problem. As planes got faster and faster, the engines started choking out at a certain speed. It seems that the air, instead of going into the cowl of the engine, encountered a wall of still air and engine cowl and so split and went around the engine. Puzzled, the researchers wondered how the falcons could still breathe at such incredible speeds. Looking at the falcon’s nostrils, they found the answer. In the opening of the nostril is a small cone that protrudes a bit. Fashioning a similar cone in the opening of the jet engine, they discovered that the air could pass into the engine even at great speed. Once again a human invention is preceded by an animal adaptation.”

Peregrine Falcon Nictating MembraneIn the picture to the left, you can see another adaptation, the thick, clear nictating membrane, or third eyelid, on the falcon’s eye. See how the right picture’s eyes looks dull (this is easier to see in the large version, so click on the picture)? His nictating membrane is down in the right hand picture.

Crocodiles, lizards, birds, frogs, most species of sharks and some species of mammals have nictating membranes in the eyes. Even we humans have a nictating membrane, but like many things on our body, they are apparently useless and only remain as that pink lump in the inner corner of our eyes.

The peregrine’s nictating membrane is particularly thick and clear. This allows for maximum eye protection during the incredibly speedy dives without obstructing vision. As well, it holds moisture on the eye so the cornea doesn’t completely dry out. There is also a gland, called the Harderian gland, that works in conjunction by secreting a viscous solution behind the nictating membrane that further keeps the cornea nice and moist.

Peregrine Falcon ("Etienne")It’s so cool to get that close to a peregrine so that you can actually see these neat adaptations.

We had been scheduled to go check on the nest at the Uptown Theater, but we got a call from Matt (Shedd Aquarium) saying he was taking care of the Uptown and would meet us at our last destination – the Evanston Library.

We got to the Evanston Library ahead of Matt and went inside to look out the bank of windows that faces the nest. Last year, we ID’d the female from this vantage point as she was sitting up on a crossbeam above the nest. The nest itself isn’t visible from inside. This year, however, the female still had some time to go on the eggs, so she was sitting tight.

When Matt got there, we all decided to go have some nosh at the pub across the street. This is where Mary and I watched last year and it is the most perfect place I can think of to watch peregrines and drink a beer.

Matt informed us that the Uptown chicks had hatched and the adult pair was a aggressive as ever. For the next 40 minutes, I listened to Mary and Matt trade stories from their years in the program (18 for Matt, 20 for Mary). We really had a good time.

Finally, Matt spotted the male. He landed on an outcropping on the Marshall Field building to the west of us. Mary and Matt hadn’t finished their beers, so I volunteered to go put more money in the parking meter and then take my scope down the street to try to get the legband numbers on the male.

I sat down there for a half hour before Mary and Matt found me. I never did get a GREAT look at the male’s bands, but I got enough that I can say, tentatively, they read black 48 over green M. The only thing I can’t say for sure is whether the 48 is 48 or 49. 48/M belongs to a 2003 male named Squawker and 49/M belongs to his clutchbrother, Brass. The brothers were born on the WEPCO Pleasant Prairie Power Plant in Pleasant Prairie, WI.

Hopefully, I’ll get another try at his bands! We didn’t get them last year either.

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~ by Steph on May 4, 2007.