“Bird Migration is the world’s only true unifying natural phenomenon, stitching the continents together in a way
that even the great weather systems fail to do.”
~Scott Weidensaul, Author & Naturalist
A man stands alone on a mountain in a remote part of Pennsylvania, binoculars trained to the sky on a gliding stream of Red-tailed Hawks. His lips move as he counts each bird. During a brief break in the stream, he bends down to pump a handheld counter and tallies “107” in the 11:00 am time slot. Biting November winds sting his eyes and chafe his skin, but they don’t weaken his resolve. This mountain is his to count from. This hawkwatching post is a piece in the puzzle of raptor migration and others are counting on him.
The red-tails continue their journey, over dense forests, open farmlands, and patchwork towns criss-crossed with lines of asphalt. They travel hundreds of miles along this ridge to a famous lookout further south, where they are counted by two more on-duty hawkwatchers and admired by dozens of school children brought here to learn about raptor ecology.
The kids are taken to an Internet kiosk and shown a map of all the hawkwatch sites in North America. They click on Pennsylvania and a chart of 35 sites appears. “Why are there so many sites?” a girl asks.
“Great question!” says the education specialist. “Because the mountains in Pennsylvania form long, narrow corridors called ridges. The wind whips along these ridges and create perfect conditions for raptors to migrate.”
She spreads her arms like wings. “Raptors fly these super-fast highways in spring so they can get to their northern breeding grounds safe and sound. And they use them again in fall so they can migrate south for winter. Each season, people — that’s men, women and kids just like you and me – station themselves at lookout points up and down these highways and spend days counting every single bird that passes overhead. That could be THOUSANDS in a single day! At the end of the day, these hawkwatchers turn in their hawk counts here, at the HMANA hawkcount website.”
The above scenarios play out at lookout points all across the country, at places with lovely names such as: Cadillac Mountain, Quaker Ridge, Goshute Mountain, Hawk Mountain, and Veracruz River of Raptors. And the organization that connects the dots between them all is HMANA, or the Hawk Migration Association of North America.
The information collected by HMANA teaches us things we’ve never considered before about how and when raptors migrate. Many of these findings are published in regional “flyway” reports from the Eastern, Western, Gulf Coast-Caribbean, Central, and Pacific flyways. Others are shared at the annual conference, where hawkwatchers convene – make a pilgrimage, if you will – from distant outposts to share data and techniques that help spread their mission to advance the scientific knowledge and promote conservation of raptor populations through study, enjoyment, and appreciation of raptor migration.
And so it came to be that these hawkwatchers convened two weekends ago on the southern shore of Lake Ontario, at the Braddock Bay hawkwatch, near Rochester, NY. Braddock Bay sits underneath one of the busiest highways in the sky for hawks during spring migration. And because this was the celebratory 40th Anniversary Conference for HMANA, and the intensity and excitement among the participants was palpable.
I was a newcomer to the raptor scene, and as I sat through the presentations I gained an appreciation for HMANA and for the individual and collective work done by hawkwatchers over the years.
In a historical tribute made by Paul Roberts, an original HMANA member who fondly recalls the use of carbon-copy data sheets, participants were reminded about the contributions made by early luminaries such as Maurice Broun, the founding father of hawkwatching, and Chandler Robbins, who has banded more than 190,000 birds in his lifetime and whose numerous accomplishments to field ornithology include setting the tone and goals for making hawk counts statistically meaningful.
Other program presentations examined how the science of hawk monitoring has grown in the 40 years since it began and introduced new and surprising data derived from modern collection methods, such as satellite tracking and blood analysis.
Take Rob Domenech, president of the Raptor View Research Institute, for instance. He’s spent much of the last ten years collecting data from a lonely but enviable location in western Montana called Roger’s Pass, where Golden Eagles are so abundant that they are practically ‘in your face.’ Up to 200 eagles can be seen in a single fall day. Rob has employed satellite-tracking devices on Golden Eagles to track their migration patterns in the west. His tracking data shows that the birds over-winter in Colorado, New Mexico, and Texas, and return to breed anywhere from the Canadian Rockies to the Brooks Range of Alaska.
All this where and when data satisfies scientific curiosity, but can lead to much more than that. First, the data allows scientists to determine population estimates. Rich Conroy from Militia Hill Hawkwatch feeds his data into the Raptor Population Index (RPI) database, which allows scientists to monitor continentwide fluctuations in species abundance and know when populations are in decline from one of numerous threats, such as lead poisoning, tower collisions, or habitat loss.
Data like this has the potential to contribute to the conservation of a species. Rob Domenech found, for example, that 60% of the birds he captured had detectible levels of lead, presumably from feeding on gut piles of deer and elk shot with lead bullets. This is a real conservation concern with a simple solution: convince hunters to use lead-free bullets. They are more expensive, but they deliver a clean shot. Now, conservation educators have hard data to fall back on when educating the public about this threat.
Raptor education is a critical component of Dr. Laurie Goodrich’s role as Senior Monitoring Biologist at Hawk Mountain Sanctuary. In the face of significant declines in farmland and field nesting raptors, such as Barn Owl, Short-eared Owl, Northern Harrier, and American Kestrel, she and her colleagues devised a program to enhance conservation attention on these species by educating farmers and the general public about breeding raptors and engaged building nest boxes and reporting and mapping sightings. Again, population and behavior data was crucial to making an informed case for this set of birds.
Worldwide raptor conservation is the primary focus for Dr. Keith Bildstein, Director of Conservation Science at Hawk Mountain. Keith travels the world studying the ecology of avian scavengers – most notably Turkey Vultures (TVs) and Striated Caracas. Birds continually surprise him, like when analyzing satellite tracking data showed that TVs traveled southward from North America over the Gulf of Mexico, instead of around it, as was previously assumed. This led to an understanding that the Gulf Stream has the strongest thermals on earth; these updrafts keep the birds aloft on a low-cost avian superhighway as they migrate south.
Keith’s studies also reveal that the world’s vultures are experiencing a disturbing decline. There are 22 vulture species on earth. In just the last 14 years, the number of these species that have declined to critically endangered levels has increased 59%, from just 5 to 13 of the 22 species. Why is this a crisis? Because data from Africa and Asia show that nature abhors a vacuum, so when you remove scavenging vultures from the ecosystem, they are replaced with other, less desirable scavengers, such as jackals and feral dogs. Some of these critters bring contagious diseases like rabies, which has spread to humans and caused economic losses ranging in the billions of dollars.
Despite dire numbers and significant threats to raptors, there is optimism, in large part due to the state of conservation science today – remote sensing and GPS has improved the volume and accuracy of data – but also due to the large number of volunteers – called citizen scientists – who suffer all kinds of weather and crippling levels of boredom (on slow days!) to monitor hawks, eagles, vultures, and falcons at hawkwatches every day during spring and fall.
There is no one more optimistic than Richard Crossley, author of the Crossley ID Guide to Raptors, about the future of birding (interview here). Richard believes we are standing at a critical time and place in the public’s awareness of birds and the environment, and that technology and the media can and should be used, with no modesty or apologies, to bring others into the fold of bird watching. When birds and celebrity birders become a household topic rather than an obtuse hobby of the few obsessed, the result will be greater environmental awareness, greater participation in citizen science, and ultimately, a greater interest in protecting what’s “ours” – the birds we share the globe with.
After spending last weekend with these raptor scientists and aficionados, I couldn’t help feeling thankful for the wonderful people who volunteer to count birds, day in and day out, so that the big picture of raptor migration can be developed. And I couldn’t help feeling a little guilty that I wasn’t at my local hawkwatch more often.
The big picture of raptor migration – and ultimately the conservation of the species – depends on folks like you and me. To find a hawkwatch near you, go to http://hmana.org.
For more information:
- A History Of North American Hawkwatching to 1974 compiled by Paul Roberts
- Interview with Brett Ewald, HMANA HawkCounter and Trip Leader
- Interview: Raptor Conservation with Keith Bildstein from Hawk Mountain
- Interview: Luke Tiller on Hawk Movements at Braddock Bay
- Interview: Richard Crossley Says Forget Bird ID! What?
- Spring Hawk Watching: Best of the U.S. by Luke Tiller