Think Globally, Hawk Locally(from Audubon Magazine, September 2002)
At Militia Hill, migrating broad-wings remind neighbors to see the beauty in their Philadelphia state park –
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Not far from Militia Hill is a riffle in the Schuylkill River. This marks the fall line: to the east the land is flat; to the west are the hills of the piedmont plateau. The line marks the border between the hard continental landmass and the erosive, formerly submarine coastal plain. People settled along the fall line – in Richmond, Washington, DC, Baltimore, and Philadelphia – because the falls marked the limit of river navigation and provided a good source of energy for water-powered mills. Hawks, too, follow this edge, bringing one of nature’s most dramatic migrations past one of the country’s most populous regions. On a single memorable September day back in 1995, more than 13,000 broad-winged hawks flew past Militia Hill.
The trio of broad-wings glides off to the southwest. Although the wind is blowing gently from the south, everyone is full of expectation. Many hope that, as on each of the past five days, a bald eagle will appear. Before long Bill Murphy, a Militia Hill regular, pipes up, “We’ve got a small group streaming out there. They’re gonna kettle.” In the northeastern sky, broad-winged hawks are soaring effortlessly, looking all wing and tail. It’s a kettle, a tornado of hawks ascending a thermal. “They’re still coming in,” he says. “I’ve got 34 now.”
Among the broad-wings is a little sharp-shinned hawk. A black vulture cruises low over Wissahickon Creek in the foreground. Meanwhile, just below the observation deck, hummingbirds buzz the feeder, an immature towhee darts to the birdbath, and monarchs are busy in the butterfly garden.
This scene is pretty typical of September at Militia Hill in Fort Washington State Park, where volunteers have been keeping tabs on migrating raptors each fall since 1988.
Two decades ago the 493 acre park was a place where people went not to bird but to cause trouble. “There were some drinking problems, there were some drug problems. A lot of people did not feel safe walking alone here,” says hawk-watch organizer Marylea Klauder, a park volunteer who lives nearby. Twenty years ago, when Klauder was putting up 35 bluebird boxes as part of a state-organized Bluebird Trail, she noticed kettles of hawks from time to time. To get more people involved with the park, the energetic Klauder organized a hawk watch. Volunteers drew up plans for an observation deck, raised the $8,000 needed to build it, then sawed the planks and pounded the nails to make it a reality. The deck comfortably handles a large crew, and wheelchairs can roll on easily.
“Marylea is the heart and soul of the Militia Hill watch,” says Janet Starwood, a Pennsylvania Audubon board member and vice-president of the nearby Wyncote Audubon Society. “She connects people, from novices to expert birders and educators. She has a pile of binoculars – a whole bagful of them – for children coming by with parents. Everyone is welcome. It’s like going to Cheers, but it’s Marylea who knows your name.”
Soon Bob Puksta, another hawk watcher, spots a “loner”, a single, immature broad-wing, looking like a child’s paper cutout of a chunky hawk outlined in pencil. It’s en route, perhaps, from the spruce-moose woods of New Brunswick to the Andean foothills of Bolivia, via Philadelphia. Puksta, who lives near Militia Hill, first visited the site with his toddlers two decades ago. “It’s funny how these things develop,” he says. “You stop by once to polish the car and years later you’re involved in so much more.” Like many of the park’s 35 active volunteers, most of them recruited through the hawk watch, Puksta has put in hundreds of hours building picnic tables, doing whatever needs to be done. His children, grown-up now, have volunteered as well.
Gesturing beyond the trees toward Philadelphia to the southeast, and to the suburbs and strip malls in every direction, Puksta wonders that such a tranquil spot has survived. “It really is a green jewel,” he says.
Geography favors hawk watching here in the mid-Atlantic. This area is at the confluence of many flight paths, like tributaries feeding a river of raptors. From the lands to the north and east – Newfoundland through England and New York – migrating hawks flow through the region buy the thousands. Many of them follow the coastline, while others fly along the easternmost ridges of the Appalachians or, when the wind is right, over Militia Hill, which lies halfway between the beaches and the mountains. As they continue south, the hawks spread out like the river’s delta, many angling southwest through Texas and Mexico, others moving through Florida and then on to the Caribbean, and many others settling out to winter in southern U.S. states.
Noon comes, and several hawk watchers on their lunch hours show up with bag lunches. The birds keep coming. A Cooper’s hawk flap-flap-flap glides above a large chestnut oak; an egret flies past a gnarled tulip poplar. After a brief lull, a red-tailed hawk appears; it’s a resident, not a traveling bird, and so doesn’t get tallied.
There’s plenty of resident nature to get excited about here. Large snapping turtles and midland painted turtles prowl the creek, along with box turtles and six-foot rat snakes. The volunteers put up a nesting platform and great horned owls moved in. Recently 10 turkeys established themselves in the park. One volunteer had identified more than a dozen varieties of mushrooms in the picnic area alone. It’s been an important area in other ways, too. George Washington camped nearby, and faced off against the Redcoats at the Redoubt at Fort Hill (hence the name, Fort Washington). Militia Hill was so named because the Pennsylvania militia held positions along this ridge. Even earlier, Indians fished along Wissahickon Creek – “the stream of the yellow catfish.”
“It’s just such a wonderful piece of land,” says Klauder. “There’s lots for people to look at and enjoy besides hawk watching.” The park’s five miles of hiking trails wind along the creek, over the hills, and past a tulip poplar that measures 15 feet around. Hawk-watch volunteers planted a butterfly garden, and today it hosts monarchs, tiger swallowtails, and silver-spotted skippers, among others (60 butterfly species have been identified in the park). Songbirds appreciate the treed oasis as well. Bill Murphy once counted 3,000 warblers in two spring weekends; the bird checklist he has compiled for the park shows 198 species, including 36 kinds of warblers, and, of course, 16 kinds of raptors.
Before long, Puksta spots more hawks. “Okay, we’ve got a lot of birds here,” he says, peering through his binoculars. Light-colored and buoyant, the broad-wings climb, circling and soaring higher, then peel off in ones, twos, and threes, setting their wings and gliding off to the southwest. Flying an energy-efficient sawtooth pattern – thermal-glide, thermal-glide – some of these hawks will travel to Bolivia, some beyond.
Gathering momentum like snowballs rolling downhill, migrating broad-wing hawks pass through Central America by the hundreds of thousands. Robert Ridgely, the head of International Bird Conservation for Audubon, has lived near Militia Hill for 15 years and has written field guides to the birds of Panama and South America – wintering spots for broad-wings.
“The broad-wing is a fabulous bird,” he says. And a puzzling one. It seems that everything we learn about these hawks raises more questions we can’t answer. Why do some individuals settle in Mexico and other continue on to Ecuador, asks Ridgely, and how do the hawks elbow in among the resident hawks on their wintering grounds?
The hawk watch is more than a way to gather data, says Ridgely. “It’s a galvanized group,” he says. “They’ve become a real force for environmental action in the Militia Hill area. That’s a damn valuable cohort of people.”
Two red-tails begin playing above the trees at the edge of the clearing, barnstorming. They chase each other, then roll 180 degrees, talon-to-talon, diving and tumbling. A sharp-shinned hawk banks around a sassafras tree and flies in low and fast over the field. The feeder is suddenly vacant, and no twittering comes for the sparrows in the shrubs. At close range, the hawk looks much more substantial and predatory than its small size and light wing beats make it appear at a distance.
First-time visitor Robert Stahl, whose calf sports a colorful tattoo of a dagger sinking into a skull, looks around. Stahl, it turns out, is “way into birds,” and often watches hawks hunt rabbits along the creek below the wastewater-treatment plant where he works. “I live just five minutes away, and I didn’t know this was here,” he says. “This is nice.” Third grader Stephen Farrington arrives with his mom. It’s his third annual visit, and he wants to see “a bald eagle, or something really amazing.” Each year, in addition to drop-ins like Farrington, more than 200 students visit the hawk watch on field trips.
Far off in the distance, a kestrel flies by. The little falcon is really moving, making a low, flat beeline for the south, but Farrington is unimpressed.
Later someone spots a high-traveling bird: “Way up in the blue, above that gray cloud – an osprey.” As it flies effortlessly on gull-shaped wings, it’s hard not to envy the osprey’s mastery of air and water and its good taste in habitat and diet. Perhaps this bird summered on brook trout by a river in the north woods, or along a boreal bay, where it dined on small striped bass. Now, having cut loose, where will it winter? A sand flat in the Bahamas? A mangrove lagoon in the Everglades? Like so many hawks, it’s a bundle of contradictory forces, a graceful flyer with a quick, fatal strike.
Harvey Bass comes in later afternoon, wearing wraparound shades, a Philadelphia Eagles cap, and a shark-tooth necklace. An avid birder since his teens, he studied biology in college, then fought fires in Montana and counted warblers by ear in the Maine woods before returning to his Pennsylvania roots. Now he’s a Philadelphia police officer. He works the night shift, and hawks by day.
Bass says the hawk watch, with its naturalists of all stripes, has further opened his eyes to the mysteries of fall. “There are all types of migrations going on this time of year – dragonflies, monarch butterflies by the thousands. We had snow geese real early this month.” But he’s most amazed by the big broad-wing flights. “You can see them all over here,” he says looking out over the trees, “horizon to horizon.”