On August 30th, I got on a plane to Minnesota. Here's me, having successfully checked one bag and hoping that the other one wouldn't be too big for the little carry-on boxy measuring thingy at the gate. Spoiler: it wasn't. Why Minnesota? The answer has to do with the magnificent creature below. For the next two months, I will be doing a traineeship at Hawk Ridge Bird Observatory here in Duluth, Minnesota. What do I do all day? I count hawks! Sometimes they're just black specks on the horizon. Other times they come close, like this Red-Tailed Hawk. I'm going to be learning how to identify them, both close up from their markings, and from far away, using subtle clues like their shape, how they hold their wings, their flight patterns, and how much they flap. It's no easy task, and before the hawks can be identified and counted, we have to find them. Luckily, Hawk Ridge Nature Reserve is located on a hill, looking out over Lake Superior. This is the view from the count station. The blue in the distance is water and the sky over the lake (it was a hazy day today). The hawks mostly come from the northeast (to the left, in this photo). They're on their way down from Canada to warmer wintering grounds farther south. Some of them won't go very far; others will travel all the way to Central and South America. The hawks don't like to fly over the vast expanse of water that is Lake Superior (would you?), but they would rather not stray from their migration route. So they turn southwest and fly right along the edge of Lake Superior. This route has another benefit for the hawks, too. As you may remember from chemistry class, water has a very high specific heat capacity; that means it takes a lot of energy to heat it up. Land heats up much more quickly. As the sun shines, the air over the land heats up more quickly than the air over Lake Superior, and it begins to rise, replaced by cooler air that flows off the lake. These rising air currents are known as "thermals," and many types of hawks use them to facilitate migration. It's much easier to glide in a spiral up a thermal, then spread your wings and glide down to the bottom of the next one, than it is to flap-flap-flap all the way from Canada to Mexico. The presence of a ridge at Hawk Ridge creates updrafts, which also help the migrating hawks stay aloft. All in all, it's a good place to migrate, if you're a hawk. Today, we scanned the skies for specks to identify. Sometimes we were rewarded with looks at birds like this sub-adult Bald Eagle. The black tips on this bird's tail feathers and the brownish markings on its white head mean that the bird isn't quite grown up yet––it's less than five years old, but it hasn't just hatched, either. A full adult Bald Eagle will show a pure white head and tail. This is our owl decoy. It's a stuffed Great Horned Owl, set up on a pole near the lookout point. It wobbles back and forth, looking quite realistic. Why put up an owl when you're watching hawks? Owls are nocturnal predators, and after dark, they may attack roosting diurnal raptors. Hawks are aggressive towards owls, and many will fly close to the decoy, swooping and dive-bombing and generally putting on a good show. We got some breathtaking looks at Sharp-shinned Hawks and Merlins as they swerved and dove at the owl, which ignored them entirely and kept wobbling in the wind. Here are our counters, or clickers, or tally devices, or whatever you want to call them. Attached to a board and bungeed to the railing of the count platform, they make a handy way to keep track of large numbers of the most common species. It's easier than writing numbers on data sheets, then erasing them, then re-writing them. From left to right, we have Bald Eagle (Adult), Bald Eagle (Sub-adult), Bald Eagle (Juvenile), Sharp-shinned Hawk, and Turkey Vulture. Then there are a few left over for other species that happen to be particularly common on a certain day. Or we can get all fancy and use adjacent counters for the tens and ones places, for easier data entry. In the middle of the afternoon, the count platform got a call, via walkie-talkie, from one of the banding stations: an adult Bald Eagle had been captured. We headed down to see the magnificent bird. It remained very calm the whole time we were there. After the bird had been banded and everyone got photos, it was time to let it go. The eagle gave a couple powerful wingbeats, and we could hear the feathers whooshing against the air. Then it banked slowly and headed towards a stand of aspen trees, where it perched just out of view. It was a wonderful end to my first day.
This morning (Tuesday) saw a huge migration of small songbirds and thousands of Common Nighthawks, though it was a slow afternoon as far as hawks were concerned. More details and posts to follow!
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Welcome! Language Learning Welcome to Hawk Ridge A Massive Migration A Happy Birdthday Photos from the Week Visiting the Banding Station A Watched Kettle Never Streams Food, Part 1 The Big Picture Last Weeks at the Ridge Belize, Part 1 How to Look at Birds, A Guide (or: Belize, Part 2) All Creatures Great and Small La France! Kids and Language, Again Musée Fenaille More Photos from France Food, Part 2 Building Nests in California Please Do Not Pet the Woodpecker Condors and Creatures in Big Sur A Day at Hastings AuthorI am a high school graduate taking a gap year before college. I’m interested in birds, biology, and the natural world, as well as history, foreign languages, writing, and reading. Archives
July 2016
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