Goldens at My Wing tips
Soaring high above a Pennsylvania ridge
DAVID BRANDES
Bald Eagle Mountain is the western-most ridge of the ridge-and-valley geographic area of central Pennsylvania. This long, linear ridge (approximately 90 miles from Williamsport to Altoona) is well known by glider pilots for providing superb conditions for ridge soaring. On a windy spring or fall day, the local glider port is busy towing glider up by prop plane to 2,000 feet, just above the ridge, where they can easily spend the day skimming the ridge or soaring in thermals thousands of feet over the valley.
But they are not alone - a semi-annual migration of raptors occurs here, as happens on many or perhaps all of the parallel ridges of central Pennsylvania. The late-fall golden eagle migration in particular excellent along this ridge far west of the famous Kittatinny.
After several years of watching the procession of hawks, eagles, and gliders along the mountain from the ground, I was wondering what the view might be like from one of those gliders. Lucky for me, during these years I had developed a friendship with Karl Striedieck, a legendary glider pilot who held a one-day gliding record for many years of 1,000 miles, from Lock Haven, Pennsylvania, to Oak Ridge, Tennessee, and back (see National Geographic, March 1978). Karl is also a raptor and golden eagle enthusiast and had offered to take me up for a hawk's eye view of the king of North American birds.
The weather forecast sounded right for a golden eagle flight (that is, strong northwest winds, partly cloudy skies, and occasional flurries) one Saturday in mid-November last fall, and we agreed to meet the next day to give it a try.
I got to the hawk watch early that morning, on the hunch that we were due for a good flight. Sure enough, the first golden flew by at 8:00 a.m., just as I got there. By the time we headed out to the glider port at 11: 30, I had already counted 11 goldens and one adult bald eagle, with a smattering of redtails. What was already a great day was about to get better. We were in the air just after noon, getting the short tow from the valley floor to the top of the ridge. With a pop of the tow chain, we were free to float the ridge with the eagles. I was fortunate enough to be sitting in the front seat of the cockpit where I could spot birds as we approached. Almost immediately upon climbing the updraft, we passed some redtails, and then I noticed our first big bird, high and straight ahead - an adult golden eagle facing out over the valley into the strong northwest gale.
Now, the trick to a close encounter is to get above and behind the bird and then glide up alongside as slowly as possible. Unfortunately, a Grob two-seater glider does not have quite the aerodynamic performance of a golden eagle, and so this can take several turns, especially since the typical flight speed of the eagles (approximately 20-50 mph) is much less than that of the glider. We never did get very close to that first eagle but did notice some interesting behavior - the bird seemed to head out into the wind over the valley below cloud streets to gain altitude, and then to turn and glide off to the south toward the ridge. Cloud streets are often present on windy fall days after the passage of a strong cold front, and are a very reliable source of lift for glider pilots (and apparently, eagles).
We headed off to the southwest to just the sound of the whistling wind, buzzed past my friend at the hawk watch, and continued down the ridge. A few miles farther we found another adult golden riding the ridge updraft. After several excruciating (for me) banked turns we were in position for a close pass. It is an exhilarating and mind-numbing experience, cruising past a gliding golden eagle at less than 30 feet. It was interesting that the eagle seemed completely unconcerned about the big stiff white "bird" alongside - must have something to do with being the boss of the airways. When a glider does get too close, eagles either bank off and flap away, or just drop and steer out over the valley. After a couple circles to regain altitude, we realized that we were unable to get enough lift to get above the eagle again, as that section of ridge has a rather gentle slope and the updraft was not very strong.
We then decided to head back upridge, with the idea that we would intercept more birds coming toward us down the ridge. By the time we got back to the hawk watch, we had passed two more goldens and a good number of redtails. We pressed on to the northeast along the smooth northwest flank of the ridge, and then, crossing the Interstate-80 gap, I noticed a juvenile golden eagle circling below. We tried briefly to circle with it, but with our much larger turning radius it was difficult to keep track of the bird. As we pulled out to head upridge, another eagle cruised by just overhead, this time an immature bald. Soon Bald Eagle Lake was stretched out below us, and I realized what a convenient fast-food stop it must be for the eagles migrating along the ridge.
While gliding on to the north at 80 knots, we spotted another adult golden zipping by below. Then we flew what seemed like a long empty stretch of ridge, seeing only the occasional redtail; however, I noticed that any birds low along the brown oak treetops of late fall would be effectively invisible from above. I continued to enjoy the new perspective and feel from above the ridge as the strong current of air pressed up from below. It was now past 1:00, and the snow showers were building, so we turned back south at Lock Haven toward home.
Before long we saw a pair of goldens below us and out over the valley to the right. Two adults, male and female, were gliding within 30 yards of each other, perhaps a mated pair. This time we already were in perfect position for another close pass, and we sneaked up behind. Going as slowly as possible, we slid past the pair of unconcerned birds at pointblank range. The sight of a wild golden eagle staring back at me from just outside the glider was as close to raptor heaven as I've ever been. Soon, however, the eagles shook us off by flapping southward toward the ridge. Unable to resist, we circled back for a second pass. Again we got so close to the unwary pair that I briefly contemplated that checking out at 30 years old with a golden eagle in my lap wouldn't be such a bad way to go!
After that, the rest of the flight back to home base was anticlimactic, but we did notice a handsome dark-morph roughleg below us just upridge from the hawk watch and calculated it should be there in about 10-15 minutes. Upon returning to solid ground and straightening my stiff back, it was back to the hawk watch, where we were enveloped in a snow squall; I learned that a dark roughie went past right on cue, and nine more goldens had been sighted. The day's final tally included 22 golden eagles and two balds, but it is not these numbers I will always remember. Rather, it is the privilege of gliding the ridge with those magnificent golden eagles.
David Brandes is an assistant professor of civil and environmental engineering at Lafayette College, Easton, Pennsylvania.
Since his teens, he has been an avid student of raptor migration. His most recent raptor project involves documentation of the spring migration of golden eagles through Pennsylvania.