Hawkwatch Update Archive - 2011

Below are the weekly Riding the Winds updates from the 2010 Hawk Watch season on Cadillac Mountain, written by Delora Hilleary, the 2010 Raptor Intern. Earliest reports are at the bottom and later reports are at the top.


Tuesday October 11, 2011. The end of this season has come, and even as I sat on top of Cadillac with my binoculars one final time, it didn't feel as though it should be my last day. Alas, I became far too aware that my time as the raptor intern at Acadia National Park was limited, and soon I must travel further down my path towards a future of bird research.

However, just because the rangers and I are packing up Hawk Watch for the season, it doesn't mean that the grand flurry of migration is over. A few raptors don't feel the push to migrate until October, or even November, as these are the raptors that do not need to travel as far as many of their cousins. Indeed, many interesting sightings and trends have been documented by local volunteers who continue to collect Hawk Watch data after the end of our official program. Though most of the common raptors we spot over the season are already well on their way out, three notable species make the journey later, the golden eagle, peregrine falcon, and northern goshawk.

The golden eagle and northern goshawk are larger birds that can tolerate mild winter conditions, and therefore only travel as far as the winter dictates. Peregrine falcons are truly wanderers and travel to the beat of their own personal tune.

As all of the raptors that migrate through Acadia are weather dependent, in a world of changing conditions, keep an eye out around you - you never know who will be travelling far and wide in the sky, on a grand mission of survival. Come next fall, Hawk Watch will once again continue on Cadillac observing and counting, with the help of any and all visitors and locals at Acadia National Park. Hawk Watch is a strong citizen science project that I am proud to have been a part of, and I suspect my own hawk watching days are far from over. I hope to see you up there again someday!!

-Delora Hilleary


American Kestrels sketched by Delora Hilleary

NPS/Delora Hilleary

Monday October 3, 2011. With several years of birding under my belt, I definitely can say that sightings of raptors are often my most satisfying. I tend to feel a little rush of elation watching them, no matter which species it is. Despite my attempts to treat all of my raptor observations as equal, it is inevitable that a couple of favorites worm their way into my heart. The falcon family was one that did just that, as I love watching them slice through the skies with seemingly little effort and much grace.

One colorful falcon tends to treat us with close looks as they pass by on the way down to the Gulf of Mexico. Many times I can clearly see their distinct facial striping or intricate patterns through my binoculars as they pass by our heads. Their coloration along with their pointed wings makes them unmistakable, so it is usually a matter of waiting for them to get close to determine if the small raptor coming our way is an American kestrel. Occasionally a merlin can trip up my identification too, but luckily a merlin's dark coloration tips me off as soon as I can get a true look at it.

The Hawk Watch continues only through October 11. We are only 200 yards down the North Ridge Trail on Cadillac Mountain from 9 am to 2 pm weather permitting. Be sure to dress warmly, as it is finally beginning to feel like fall up here!

-Delora Hilleary

Northern Harrier

Sketch of details of a Northern Harrier

NPS/Delora Hilleary

Thursday, September 29, 2011. Around the age of fifteen, before I could drive but after I began setting up bird feeders myself, I started to get more serious about birding. My parents recognized a growing passion, and so they took me out for a special treat. A grand journey was taking place in the fall in Alamosa, Colorado, where thousands upon thousands of sand hill cranes, snow geese, and other migratory birds gathered at the wetlands on their way to Texas and Arizona. Indeed, as we got out of the car and ventured into the wetlands, my parents and I stood in awe at the sight of thousands of wings fluttering around us. These migrants weren't alone though - many other birds skulked around the gathering, including some opportunists of the raptor family. It was here that I got my first look at an unusual raptor stalking the grasses at the edge of the migratory gathering.

Though it flew close to the ground, it was easy to pick this bird out as a raptor. Its long wings and tail form its distinctive shape, and that handy white rump patch allows this bird to be identified readily as the northern harrier. Here in Acadia, harriers are often spotted on their migratory coastal path, flying much higher than they usually would be if they were foraging.

Many call this raptor by another name - the marsh hawk - which can present a little confusion amongst fledgling birders. The alternate name aptly describes the habitat that it prefers - marshes, wetlands, and grassy fields - anywhere where it can course low to the ground, listening for prey. Its distinctive facial disk also aids its hearing, since it focuses even the tiniest of sounds into its highly developed ears. This makes the harrier unique in terms of hunting techniques, for no other raptor sports a facial disk and keen ears like the harrier does.

The northern harrier does not pass through in enormous numbers (only 3.5% of total birds counted), but we get steady sightings of them on Cadillac Mountain throughout the season. After the anomaly of thousands of broad-winged hawks, we have counted over 4,717 migrants so far this season, and October is still to come! We are anticipating a rush of American kestrels sometime soon, as those numbers are still well below seasonal average. To get a good look yourself, please come and join us anytime from 9-2 weather permitting, and borrow some binoculars if you like. Walk about 200 yards down the North Ridge Trail and experience the fun and adventure of an incredible year!

-Delora Hilleary  

Broadwinged hawk kettle

Sketch of kettles of broadwinged hawks

NPS/Delora Hilleary

Thursday, September 21, 2011. In the early morning of the 17th of September, I hurried my way up to the top of Cadillac to work, aiming to get up there earlier than usual. The day before had bitterly cold, howling winds, but this day was forecast to be clear and breezy Northwest winds - perfect for hawk migration. Since we have had so few North wind days so far, I anticipated a good number of raptors to be added to our count.

Pleasantly, several park volunteers, local birders, and visitors were already there, and had a tally of early morning raptors already spotted. On north wind days, I'm grateful for their presence, since it means more help to count and identify the birds. I quickly whipped up a new data sheet and set up, ready to settle in for a big count. When 10am rolled around, a few large kettles of broad-winged hawks appeared to rise right out of Bar Harbor. We counted at least 100 birds in that hour alone. Thus we got excited - we started tossing around predictions of how many raptors we'd see that day. Some said 300, others tossed out a risky estimate of 600. Indeed, we had no idea about the phenomenon that was about to occur.  

As I filled out another weather measurement for 11am, we were caught by surprise as broad-winged hawks filled the sky out of nowhere, appearing in kettles of 200, 300, and then more, until they looked like swarms of giant insects circling the sky. Chaos ensued as we scrambled to keep a count of these kettles, and I quickly ran out of room on my count sheet. Only by the combined powers of true citizen science from professionals, amateurs and visitors did we manage to count 3,200 raptors by the end of the day, with 3014 broad-wings alone. Indeed, this single day smashed our normal seasonal count, and left a trail of shattered records in their wake all the way down the coast.

Will we ever see such numbers again? We'll never know unless we look! I invite all of you to come up with some warm clothes and help us out, because you truly never know what will happen next. Keep an eye out on the forecast for North wind days, as those tend to be our best days. We are watching every day (weather permitting) from 9am to 2pm just 200 yards down the North Ridge Trail. I hope to watch with you!

-Delora Hilleary

Drawing of raptors by Delora Hilleary

Raptor drawings by Delora Hilleary

Delora Hilleary

September 15, 2011. As I went out daily to feed my horses or wander in the fields through my childhood in Colorado, I often remember a "screeeeeeeeeee" echoing against the mountains. When I heard this cry I could often look up towards the sound and see a very familiar silhouette against the sky. Though this raptor seemed to have many different color patterns and markings, I would always recognize its species for what it was.

The overall powerful build, the broad wings, stocky chest - indeed the red-tailed hawk is perhaps the most seen and commonly known hawk in many parts of the United States. In part this is due to its prominence - as a buteo, it prefers soaring over wide-open spaces or road corridors. It also chooses perches where it can take stock of all of its surroundings, making it easy to spot from the road. Having taken part in many road trips across the Western USA, recognizing this bird in its many color forms has become a matter of instinct instead of scrutiny for me.

This familiarity has allowed me to use the red-tailed hawk as a comparison to other raptors. It is indeed how I initially realized I was looking at a broad-winged hawk the first time one flew over my head - I knew I was looking at a buteo, but it surely was not a red-tailed hawk. The shape and girth of the bird was different. Thus, my logical conclusion fell to identify the raptor as a broad-winged hawk. Using the red-tail as a comparison is a technique I still employ now; especially since similar Eastern raptors are new to me.

Of course, nature likes to toss curve-balls at all of us. Earlier this week I saw a raptor who seemed to have some rufous on its tail, and since it was flying directly towards me it was difficult to pick out anything beyond that. I immediately assumed it was a red-tailed hawk based on the reddish-like color, but when the raptor passed overhead and looked at from a different perspective...it was a juvenile peregrine falcon! There is always room for more practice, even for those who are trained!

Right now, the migration season is at its prime, and we've recently reached the 800 birds mark. Indeed, we knew that peak season was approaching when the first true North wind blew all day last week, bringing 313 raptors over our heads in one day! I am obsessively checking the wind forecasts these coming weeks, for any North wind day is going to be a great raptor migration day!

The more eyes on the sky, the easier it is to find a bird and the fewer birds we'll miss! So I invite everyone to join us 200 yards down the North Ridge Trail on Cadillac Mountain to join us and help us out! We are there from 9am to 2pm every day, as long as it is not too foggy or rainy. I hope to see you up there!

-Delora Hilleary

Raptor sketch by Delora Hilleary

Drawings by Delora Hilleary

Delora Hilleary

September 1, 2011. As I bumbled my way through fifth grade, an interest in the feathered creatures of the sky began to embed itself into my very being. Yet, as I watched birds flit in and around the trees, I began to wonder if I bit off more than I could chew. Trying to figure out subtleties between bird species seemed like a daunting, impossible task. How does one tell one aerialist from another? Indeed, I started to drive myself nuts flipping through my bird book, attempting to figure out by myself what the mystery visitor over my head was. Thankfully, with practice, I've figured out a few techniques to help me learn our flying visitors. One such technique that works well for me is utilizing illustration. By drawing a new bird using photo references, I can get a "feel" for the bird, and figure out the best places to look in order to nail down an identity. The drawing to the left is an example of one such practice sketch

Since I'm a Coloradan interning here in the Northeast, there is a few new raptors that are unfamiliar to me. One of those is the broad-winged hawk, a primarily Eastern bird. Thus I drew the hawk from various angles, taking note of important characteristics. Of the raptors that pass overhead, the broad-winged is the one who has the farthest to go. It typically likes to winter in various parts of Central and South America, sometimes even going farther than Brazil.

The first thing I look at is the shape of the bird. The broad-winged is a buteo, so it is built for soaring. The broad wings, the short tail, and slower wing beats sets it apart from other types of raptors. I then try to get a look at the coloration - the broad-winged has a black "outline" on the trailing edge of its wings, and its back is a clean brown without any speckling. Adult birds also have a banded black-and-white tail. Those color differences set it apart from birds of a similar size, like the goshawk.

Broad-winged hawks are just starting to appear in numbers when we get that good north wind, and dry, sunny days. To get in some identification practice of your own and help us spot birds, Please join us at the top of Cadillac Mountain every day from 9am to 2pm (weather-permitting). We also are getting a real variety of birds migrating as well, so one can use comparisons to help learn the raptors through practice. We are perched about 200 yards down the North Ridge trail, and you can even borrow some binoculars from us if you do not have any of your own. See you up there!

-Delora Hilleary

Park ranger stands with other people on rocks.

Hawk Watch provides you with the chance to see migrating raptors up close.

NPS/Karen Lanier

August 11, 2011. Hello! I am Delora Hilleary, this year's raptor intern. Many of you may remember me from this year's "View from the Aerie," the weekly peregrine update. I enjoy drawing and biology, and I am working towards my goal to be an ornithologist. I have been enjoying my new experiences up here in Maine, as this place is much different from my mountainous Colorado home.

A touch of fall introduced itself to Acadia last week, as I had my first sighting of migrating shorebirds on the rocky coast. Some would greet this fall prelude with dismay, but my reaction to these sightings was sheer delight - the season of migration is upon us.

The word migration instills the feeling of a daunting journey, one that we humans can hardly imagine making without bikes, cars, or planes. Yet a vast number of species take on a grand journey, ranging from the tiny dragonflies to the massive whales. For each of these species, it is not a simple jaunt out into the world for pleasure or new experiences. Indeed, migration is all about survival. In Maine, these animals are on the move to escape the incoming harsh weather of winter and to find abundant food resources after the local ones are depleted.

Most raptor species are no different. As the apex predators, they must move along with their prey, and as such the falcons, hawks, and eagles of the north spread their wings to ride the river of winds to the warmer south. Researchers have an idea of where they go, and which migratory corridors they may use, but a haze of mystery still surrounds many aspects of raptor migration. How do they know when it is time to go? How do they navigate? Do genetics play a role, or could it be a learned behavior?

In order to discover the answers to these questions, observation and data collection needs to happen continually. Unfortunately, there never seem to be enough scientists who are able to watch the skies in all areas of the world, all the time. Thankfully, it's not just the professionals who are seeking to contribute to science anymore. In order to facilitate more data collection, and thus more thorough and accurate studies, scientists are turning to the general public for help. Many people observe the natural world and its phenomena as a hobby, such as amateur stargazers, insect collectors, teachers, and of course, birders. Sightings by non-professionals can add to scientific data, thus increasing our understanding of the world around us. With that knowledge there comes a better ability to protect our national resources, the primary goal of national parks.

Acadia National Park is seeking ways to promote such "citizen science," so that visitors can help acheive the park's mission by contributing to ongoing studies in the park. Hawk Watch is a very successful example of such a program, since anyone can come up and help us spot and count raptors in the sky. All the raptors we see during the program are entered into a national database, www.hawkcount.org, where researchers can use the data for efforts in conservation and population monitoring.

How would you like to participate in a real scientific study? I invite you to come join rangers, volunteers, and myself starting August 16 from 9am to 2pm every day, weather permitting, on top of Cadillac Mountain. You can find the Hawk Watch just 200 yards down the Cadillac North Ridge Trail, where you can help locate raptors and learn some raptor identification skills as these birds soar on their southbound journey. I hope to see you up there!

-Delora Hilleary

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