One day a few years ago, my friends and I started looking up the names for groups of animals. Everyone knows the generic ones, like a "flock" of birds and a "herd" of cattle, but it turns out that if you dig deeper, there are some pretty awesome group names. Have you heard of a murder of crows, an unkindness of ravens, or a parliament of owls? How about a smack of jellyfish, an exaltation of larks, a romp of otters, or a pitying of turtle doves? If you're like me and you're fascinated by this, you can check out lots more animal group names here and here. One group of animals in particular has been on our minds lately here at Hawk Ridge: a kettle of Broad-winged Hawks. "Kettle" isn't a group name quite like the others; it doesn't refer to the species of birds involved, but to the form that they take as they fly. In this post, I explained a little bit about how thermals work, and for the sake of my typing fingers and the sanity of those of you reading this post whose job it is to explain thermals all day, every day, I'm not going to go over it again in detail. Visit the links above for an explanation, which can be as simple as "warm air rises!" or as complicated as specific heat capacity and pressure and inversions and cool stuff like that. In a nutshell: hawks have a long way to migrate, and they would rather not expend a lot of energy if they can help it. So they soar up on thermals, circling and circling and getting as high as they can before gliding down to the bottom of the next thermal, and the next, and the next, all the way down to South America. Here's a diagram I found on this website that explains the process pretty well. So what exactly is a "kettle" of hawks? Usually, birds riding thermals don't do it alone. When one bird finds a thermal, others fly in to join it, and pretty soon they make a swirling mass of hawks, called a kettle. It's pretty spectacular to watch, as more and more birds join the kettle and your binocular view fills with dozens or hundreds of birds. Above is an example of one of these kettles. It's really hard to take a decent picture of one, because they can get so high up. The birds in the picture above might look like specks to you, but most of the time we're lucky if we can get that good a view of them. Sometimes kettles can be so far away that they're barely visible in a spotting scope (with a maximum of around 60x magnification). And sometimes the kettles can be right overhead, so you have to crane your neck back to keep them in view and count the birds. Counting kettles of hawks is one thing I've been learning how to do in the past few weeks. With a few exceptions, it's not a good idea to try to count the birds in a kettle while they're still circling in the thermal. It's when they start "streaming" off the top of the kettle that they form a nice, countable line. In the flight diagram above, the middle bird is streaming: gliding from the top of one thermal to the bottom of the next. When hundreds of hawks do this at once, it's an incredible sight. In my first post about Hawk Ridge, I talked about our clickers, which we use to tally the different species of hawks we see. Most of the clickers are mounted on wooden boards, but we have a few loose, handheld clickers, which we use for kettle counting. On a big Broad-wing day, the count platform echoes with clicking as two or three counters at a time tally their kettles. I keep mentioning Broad-winged Hawks (or "Broad-wings" or "Broadies"). What are they, and what's the deal with Broad-wings and kettles? This is an adult Broad-winged Hawk. It has a reddish-brown head, black and white tail bands, and mostly whitish wings with a black outline on the trailing edge. (This particular bird is molting a few of its tail feathers and maybe one of the outer feathers on its left wing, which is why it looks a little ratty). But, as I quickly learned when I got to Hawk Ridge, the vast majority of hawks can't be identified by their color pattern or plumage characteristics. They're simply too far away. Instead, we focus on the bird's overall shape, general light and dark coloration on major regions of its body (for example, even from a distance, the pure white head and tail of an adult Bald Eagle stick out in contrast with its black body), and its flight pattern. So, let's take a more realistic view of things. Here's a highly cropped version of that first kettle photo. Aha! Now you can't see the reddish color or whitish underwing or tail bands, can you? Instead, let's look at the shape of these birds. As their name suggests, they have wide wings. They also have a pretty short tail, especially when it's fanned out. Their body is pretty stocky, and overall they have a compact appearance. These body proportions are common to most hawks of the genus Buteo, including Red-tailed Hawks and Rough-legged Hawks. Broad-wings are the most common hawk in these big kettles, and they are the hawk that most likes to soar on thermals. Often, of the hundreds of birds in a kettle, all but a few will be Broad-wings. But usually a few other raptors join the Broad-wing kettles, so counting the hawks isn't quite as easy as clicking a clicker. Before the raptors start streaming, you have to go through and pick out anything that might be different, like these: Counting kettles is fun, exciting, and exhausting. It makes us all want neck massages. It has brought me dangerously close to falling off the railing of the count platform several times. It can be immensely frustrating when the birds in a kettle fly higher and higher and just refuse to stream off and be counted. But kettles can also lead to some truly incredible hawk totals. Here's the count board at Hawk Ridge on Saturday afternoon. The left column is the past hour, the next column is the day totals, and the right-hand column has season totals written in blue. By the end of the day on Saturday, the counters had tallied 16,815 Broad-winged Hawks, along with 459 Sharp-shinned Hawks and 276 Bald Eagles. If you're interested in our season totals, check out the Hawk Ridge page on HawkCount. As of yesterday, our raptor total stands at 50,081. Our 50,000th bird was an adult Peregrine Falcon that appeared out of the fog that was beginning to move in on the ridge. We were all glad it was a bird we could point to, and not a distant milling speck in one of the kettles.
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In the last few days, I've had the chance to visit the Hawk Ridge raptor banding station. While our job at the count platform is to tally every raptor that goes by, the folks at the banding station want to get up close and personal with just a few (but the more the better!). If we see birds from the count platform that are flying pretty low and seem to be heading in the direction of the banding station, we radio the station and they start "fishing" with their lures. When a raptor sees what it thinks is an injured bird on the ground, it often can't resist the possibility of an easy lunch. Frank Nicoletti, the banding director, traps the birds as they come in with one of three types of nets. Dho gazza nets collapse over a bird when it hits them. Bow nets can be sprung to swing over a bird on the ground. Then there are mist nets, similar to the kind used to catch songbirds. Mist nets are made of fine black cord, and they are almost invisible to a bird. (Judging from the number of times I have nearly walked into a mist net, they're almost invisible to humans, too.) When the bird flies into the net, it gets tangled in the loose, baggy netting and can't get out. Regardless of the type of net, banders know how to carefully and gently extract the bird so it doesn't get hurt, at which point they can weigh it, measure it, and put a band on it. The process is pretty much the same for songbirds and raptors, except that raptors are much bigger and have extremely sharp beaks and talons. If you get pecked by a songbird while taking it out of the net, there's usually no serious harm done. Getting pecked or "footed" by a raptor is a different story. The valiant banders and trainees at the banding station sport scratches all over their hands and an uncanny ability to ignore the blood dripping down various parts of their body. But I'm exaggerating things a bit. The banders know what they are doing, and Frank was kind enough to show me around the station the other day. Here I am holding an adult Sharp-shinned Hawk, which banding trainees Reed Turner and Alan Moss taught me how to handle safely, gripping it in just the right place to avoid getting footed. Here's Alan with the sharpie, showing off the bird's short, rounded wings, long tail, and the beautiful reddish barring on its chest. We can tell this bird is an adult because of that reddish color on its chest, and because of the red eye and the slate gray color on its back, as you can see here. The way that I'm holding the bird in the first picture is called the "popsicle hold" for obvious reasons. Alan is demonstrating the "three-quarters hold" which is used to show the bird's wing. These photos were taken during a slow period at the banding station. But for a while during my visit, it was pretty busy, and I'm not referring to humans. The banders sit in a blind (a small hut painted brown and green to at least sort of blend into the trees) with the nets in front of them in a field. Raptors come in from over the trees in front and stoop to catch the lures. Alan told me that's the coolest part of his job: while they don't see as many birds as we do at the count platform, the ones they do see are diving in close at amazing speeds. I got to watch at least three Sharp-shinned Hawks and one Northern Harrier come into the station and get banded. On Monday, the banding station caught a juvenile Northern Goshawk. A goshawk belongs to the same genus, Accipiter, as the little sharpie in the pictures above, but it's bigger, bulkier, and just plain scarier. (British author Helen Macdonald recently wrote a very good book about training a goshawk, which is packed with descriptions of the ferocity and beauty of this legendary bird. It's also well-written and filled with interesting history, and I'd recommend it to anyone, birder or otherwise) This goshawk was the first I had ever seen, and it hurtled low over our heads at the platform like a missile. We barely had time to reach for the radio and yell "Hawk watch to banding station: GOS!" before it went down below the trees and was caught in their nets. And since it was my first goshawk ever and only the second one caught at the banding station this year, I got to go down and see it. When I walked into the banding station, the bird was screeching its head off, and the intimidation factor was high. I have frequently heard the calls of kestrels, Merlins, and Sharp-shinned Hawks, and most birds will vocalize when they're caught, out of alarm and in attempts to scare whoever's holding them into letting them go. But this goshawk was something else. It's a very large bird and has a voice to match its size, and within the confines of the small banding blind, it was deafening. While she measured and banded the goshawk, Karen Stubenvoll (Hawk Ridge board chair and volunteer raptor bander) explained how dangerous goshawks can be, and how she has learned to be cautious and extremely respectful of the bird's size, power, and sharp talons while she handles it. I listened in fascination from a safe distance, until she asked if I wanted to hold the bird. I did. Oh, yes, yes, yes, I did. Those talons looked very, very sharp, and the bird was very, very big, and I couldn't have been more excited. Karen held it first. She looks so calm. I held it next. I look calm, too, but I assure you I was feeling like doing a little screaming of my own. The bird was warm and solid in my hands, and strong. As it called, its whole body shook, and I felt my hands slipping lower down the sleek feathers. As you can see from the picture, my two hands together barely fit around the bird's body. Eventually, the bird worked a wing free, and I let go, because I could tell that trying to readjust my grip would only result in pain, blood, and screaming. (This is why Karen held the bird first.) The goshawk took off into the forest and perched on a tree, shaking its feathers.
The first time doing anything is special, and holding this bird was no exception. It's not every day that you get to hold your lifer (in birder slang, a "lifer" or "life bird" is a new bird species for you; one you've never seen before). It was awesome to have felt this bird's heart beating and to have watched it fly free, knowing that I may be one of the few humans who will ever touch it. But if doing something for the first time is special, then doing it over and over again diminishes how intensely we experience it. I'm glad I got to hold this goshawk, but I'm equally glad that I don't hold goshawks every day. Already, up at the hawk watch, I catch myself zoning out as the hawks stream by, ticking off a sharpie on the ridge, two sharpies on the lake, a kettle of fifty broad-wings, no big deal. The sheer number of birds makes us forget that each one of them has a bill and talons and powerful wings, each one has a voice to fill a banding blind or strike terror into the heart of a flock of crows, and each one has a heartbeat.
Hey look, it's a Bald Eagle!
Maybe you weren't going to read this post. It has a boring title, and it's obviously going to be about birds again. But I hope this photo changed your mind, because this is going to be a quick one, and it's going to be photo-heavy, and it's going to feature some cool birds. The handsome dude in the photo above is a sub-adult Bald Eagle that was caught and banded at Hawk Ridge last week. This was the second eagle caught this year at Hawk ridge, and the second eagle caught by bander Miranda Durbin in one week, and also the second eagle Miranda had ever caught. The other banders are getting pretty jealous of Miranda at this point. Bald Eagles take five years to develop full adult plumage, with that famous pure white head and tail. This bird is a sub-adult, meaning it didn't hatch this year, but it's not five years old yet. It's probably a pretty advanced sub-adult (third or fourth year) because, as you can see, its head is really mostly white. But there are a few brown feathers in there. The bird also has some white on its wing feathers...
...and on the feathers at the base of its tail.
Here's counter Alex Lamoreaux holding the eagle.
Miranda and Alex and the other banders are brave souls. Let's take another look at that beak and those talons.
The bird could do some serious damage if it tried. Luckily, though, no one got hurt (birds or humans) and Alex got to set the eagle free.
So, getting to see that eagle banded was really cool. But up at the count platform, we see eagles flying by every day, sometimes as many as ten or fifteen per hour. So what really got us excited was a visit from some Sandhill Cranes.
We could see them coming from a ways away. Sandhill Cranes are huge and lanky, with long wings, necks, and legs. They formed beautiful shapes in the sky as they flew out of the clouds over Lake Superior.
Here's a (heavily cropped) picture of the cranes closer up. As if their huge size and crazy crane proportions weren't enough, they have these funky little bright red caps, too.
Here's a video from the Cornell Lab of Ornithology's Macaulay Library of Sandhill Cranes coming in for a landing. Along their migration route, they rest and feed in large groups, like the one shown here, and the sight of the cranes coming in to roost for the night or taking off in the morning is said to be spectacular.
The birds migrating over our heads at Hawk Ridge are pretty spectacular. But I have been enjoying the birds right here in the neighborhood, too. The part of Duluth where I'm staying is more rural than Newton: there are frequently bears, deer, and foxes in the neighborhood, and all the houses are surrounded by trees. The streets are wide and shady, and little footpaths cut between the blocks every so often; you can take a bike through or pass on foot through the trees without having to watch for cars.
All this is great for the birds, like this male Scarlet Tanager I found by my door last week.
There are also flickers everywhere. A flicker is a colorful woodpecker that can often be found poking around on the ground, acting like a robin. When they fly, they flash yellow feathers in their wings (or red, on the West Coast). This guy was sitting in a tree along the road, looking very handsome.
That's all for the photos! Coming soon: Broad-winged Hawks are starting to migrate in huge groups, called "kettles." I'm hoping to have some pictures soon! Stay tuned.
Thursday, September 3rd, was a momentous day. I turned 18. And it's about time! Now I can sign forms for myself, vote, get called in for jury duty, get married without my parents' consent, and do lots of other fun things! In the past, my birthday has been a funny combination of happiness and worry, as it usually falls in the week before the first day of school. In sixth grade, the first day of school was September 3rd, and my birthday gift was meeting a whole bunch of new people, none of whom knew or cared much that it was my birthday. In any case, I usually celebrate my birthday at home, or on Cape Cod, with my family and friends. When I wake up in the morning and come downstairs, my mom has made brightly colored "Happy Birthday Kaija!" signs and hung them from the light fixture above the table. Sometimes there are presents. Every year, we eat angel food cake and strawberries after dinner. This year was a little different. School isn't looming. I'm in a new place with new people, but they aren't twelve and awkward and covered with zits. I'm not with my family––we had our angel food cake in late August, before I left for Duluth. And I'm on the cusp of my first real "grown up" year to match my "grown up" age. We're not in Kansas anymore. But despite all these differences (and because of them), I had a really great birthday. Here's how it went. I woke up at what felt like a much too early hour. It had rained most of the previous morning, and we hadn't gone to Hawk Ridge until noon (the hawks won't fly in a hard rain, so there's no point in getting wet and miserable. This is a nice aspect of hawkwatching.) The air felt damp and heavy when I woke up, and I opened my blinds, thinking that maybe today would be another rainy morning. And maybe I would get to sleep a little longer. I looked out the window and saw... very little. It wasn't raining, but a dense fog had settled over Duluth. Visibility was poor, and the trees looked eerie. Despite the fog, we headed up to the ridge, driving with headlights and windshield wipers and peering anxiously around corners before making frantic left turns, hoping that no cars would materialize and hit us. We made it up to the ridge in one piece, set up the merchandise trailer, put down our bags and... waited. The fog was dense enough to block all views of the sky or the city below. If any hawks were flying in this weather, the only way we would be able to count them is if they flew out of the fog and directly at our faces. There seemed to be no point in setting up a spotting scope, and Alex and Karl hadn't arrived yet, so I poked around the top of the ridge for a while. I went a little ways on a few of the trails around the Hawk Ridge Nature Reserve. I found a lovely spiderweb covered in fog droplets. But the wet plants whacked my bare legs and the ground was slippery, so I turned back. Just when I seemed to be looking at spending my birthday morning, and maybe the whole day, on top of a foggy hill with no birds, without a sweatshirt (the weather report had said it was going to be hot!), Alex arrived. Good, at least I would have someone to commiserate with about the lack of hawks. But Alex walked to the count platform, took one look around, and informed me that we were going to go look for warblers. As long as there were no raptors, Hawk Ridge could do without its counters. We headed down to Park Point, a long, narrow spit of land into Lake Superior. On my first day, Karl told me it was "the longest strip of land in the world. Or something." It's actually the largest freshwater sand spit in the world, but hey, close enough, Karl. At the end of the point is a park, and the various stands of trees were fairly dripping with warblers (for you non-birders: warblers are small, colorful songbirds, known for their beautiful colors and songs, and also for being really hard to identify correctly because there are so many of them and they change plumages with age and throughout the year). The warblers, having started their own fall migration, weren't eager to fly in the heavy fog, so they had stopped at the park to forage for insects among the leaves. At Park Point we were below the fog, so visibility was slightly better, although we still couldn't see out onto the lake or up to the ridge. The birding was amazing. Often there were several species of warblers clustered in the same tree, or flitting from shrub to shrub as we eagerly tried to pick them out from the leaves. We saw beautiful Cape May and Magnolia Warblers, several tiny Least Flycatchers, striking black and white Caspian Terns, and many gray-brown Swainson's Thrushes hopping on the ground under the trees. We even got a glimpse of a Mourning Warbler, an elusive and uncommon bird that was a first for me. Those of you who are interested can find my full eBird checklist here. Around 1pm, we got a call that the fog was lifting over the ridge, so we made our way back to the car as quickly as we could. For birders, that means stopping only for some birds, like for a Least Sandpiper that flew circles over a flock of Ring-billed Gulls, or for a Savannah sparrow that flew so close by Alex's face that it almost hit him. Eventually we were in the car, headed to the ridge, and all was going well. Redstarts darted overhead and we tallied our first robin of the morning. And then we hit traffic. The Aerial Lift Bridge, which spans the channel between downtown Duluth and Park Point, was lifting up to let a ship go through. As someone put it to us gleefully later on, "you got bridged!" It was like one of those bad dreams where you desperately need to get somewhere or do something but your legs won't move. We could see the fog clearing and we knew the birds were flying, but we still had a ways to go. Then I saw the warbler. It was in the low branches of an evergreen tree just to our left, in someone's yard at the edge of the road. We grabbed our binoculars and found more birds: an American Redstart in the tree's upper branches, a Red-eyed Vireo in a bush just yards from the car door. We forgot all about the bridge, and before we knew it, the traffic cleared and we were whizzing towards the ridge. The fog was fast disappearing and soon the sky was clear. And the hawks were flying! We had 107 Sharp-shinned Hawks in the first hour after we arrived, and 134 the next hour. The clickers were going like mad. There was a steady stream of Bald Eagles, too, a mix of adults and immatures, and some came close over our heads. At the count platform, we have another responsibility besides identifying and counting birds. The Hawk Ridge raptor banding station is located just down the ridge from the count platform, and it's our job to radio over to the station if there's a good bird coming their way, so they know to be on the lookout. I enjoy playing with the radio. It makes me feel like I should be saying "Roger" all the time and using funky codes. Anyway, after we had been at the ridge for a couple hours, I spotted a bird out in front of us, flying fast, with pointed wings and a long, narrow silhouette. I could tell from its shape that it was a falcon, but I'm still working on my raptor ID skills. I needed to wait for the bird to get closer before I could tell whether it was an American Kestrel, a Merlin, or a Peregrine Falcon. But Karl and Alex didn't need to wait. They spotted the bird and jumped up, cameras at the ready. A few seconds later, an immature Peregrine Falcon zoomed over our heads, wings locked in a glide, headed directly for the banding station. It was amazing how quickly they caught the bird. Frank, the banding director, told us later that the falcon dove in after the lure at 80 or 90 miles per hour (well shy of that species's record speeds of nearly 200 mph, but still.) Best of all, we were invited down to the station to see it. I couldn't have asked for a better birthday present. After a long day of exciting hawkwatching, we headed home, where I finished up a great birthday with some strawberry ice cream and mini M&M's. And I received one more birthday present: chocolate owls from Karl's girlfriend, Jane. They were delicious! More news of birds and life coming soon! Thanks to Becca Webster and Janelle Long for inspiring the title of this post.
On the morning of September 1st, I arrived at Hawk Ridge at 8:30. Counters Alex Lamoreaux and Karl Bardon had been hard at work since dawn. Since I'm focusing on hawks, I come a little later in the day, because the hawk migration tends to start in the mid morning. But I arrived in time to witness the middle and tail end of what turned out to be a historically huge migration of nighthawks and passerines. The word "passerine" refers to a bird of the order Passeriformes. Birds in this order are often referred to as "perching birds" or "songbirds." They include finches, robins, chickadees, thrushes, crows, jays, sparrows, warblers, vireos, cardinals, swallows, orioles, and mockingbirds. Like raptors, many species of passerines migrate. Unlike raptors, they're small and wickedly difficult to identify in flight. When you see a soaring hawk as a black speck against the sky, it's hard to tell what kind it is. Now imagine trying to identify a much smaller black speck, only instead of soaring by above your head, it's zipping past your face, taking only seconds to pass out of sight. Remarkably, Alex and Karl were able to identify by sight most of the passerines that passed close by, and they identified other, farther birds by their size, flight style, or flock formation. Colorful warblers flashed by, Cedar Waxwings whizzed across the ridge in their tight flocks, and once in a while a woodpecker flew overhead with its uneven, undulating flight. I did my best to be useful, pointing out passerines and doing my best to count the easier birds, like Blue Jays and waxwings, which are relatively easy to identify in flight. Then Alex put me to work counting Common Nighthawks. This is a Common Nighthawk. (Photo by Eric Heisey, one of my friends from the Cornell YBE. You can see more of Eric's awesome photos here!). Common Nighthawks are not passerines; they're in the order Caprimulgiformes, and they're pretty funky-looking. They're related to owls, not hawks, despite their name, and they are mostly crepuscular (meaning they're active at dawn and dusk). Nighthawks are very distinctive in flight: they have long, narrow wings, and they sort of flutter, flying around in circles and dodging back and forth. They do this because they are aerial insectivores, which means they eat insects in the air. In fact, a Common Nighthawk needs to eat insects in the air. Its beak is practically useless, and its throat muscles are weak. Instead of picking up bugs and swallowing them, it simply flies around with its mouth open and lets the bugs go down its throat, where they are zapped by its digestive juices. Until I got to Duluth, I had never seen a Common Nighthawk. That changed abruptly yesterday morning. Nighthawks migrate en masse from their breeding grounds across the United States and Canada to their wintering grounds in South America. When I arrived at Hawk Ridge, hundreds of birds were streaming past on all sides of us. Often, they were far enough away that I could barely pick them out with the naked eye. But when I raised my binoculars... WOW. The birds wheeled through the air, rising on thermals and forming massive flocks in the sky. This behavior is called "kettling" and it's most obvious in the first photo, where you can see the birds in the center of the flock forming a spiral shape. Broad-winged Hawks are another species that forms "kettles" as massive numbers of birds ride thermals up into the sky, so you'll probably be seeing more kettling hawks on this blog when the Broad-wings start moving through, in mid-September. Here's a closer view of one of the flocks of nighthawks, where you can see their narrow silhouette and flapping flight: And here you can see the birds' telltale white wing patches and blunted heads: Everyone was impressed with the numbers of nighthawks and songbirds that we saw yesterday. All together, the counters tallied over 28,000 Common Nighthawks, the third highest count ever recorded in MN, and over 33,000 warblers. These are near-record numbers. You can read Karl Bardon's detailed summary here, and Alex's morning eBird checklist here. I want to emphasize that my own checklist is greatly reduced in species and numbers; I didn't identify nearly the number of species that Alex and Karl saw, nor was I able to count all the birds. But I'm glad to have made some sort of contribution, however small, to recording this incredible flight. And it sure was amazing to watch!
Stay tuned for more updates! I'll try to fit in some non-bird stuff at some point, too, but the hawks are starting to come in full force, so it might be all I can do to keep up. 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
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