Wednesday, February 4, 2015

PA: Eagle-Oh-Palooza on Superb Owl Sunday - Bear Islands

It's Superb Owl Sunday and the only competition I'm interested in is Eagle-Oh-Palooza over on the river. Winter is my favorite season for a ton of reasons, but top among them is the raw drama of survival on a wintery riverscape. The Susquehanna River, just ten minutes from home in Pennsylvania, provides the backdrop of an ancient landscape for some of the best wildlife viewing in the region. Even though Conowingo Dam is just ten miles south of here, the public viewing area is often crowded with people (to the exclusion of everything else it seems). I prefer the much less crowded area in and around the Bear Islands. You just have to know your back roads.

Little Chestnut and Piney Island almost touch.

My first adventure was to walk out on the very high Norman Wood Bridge. The absolutely best time to venture out there is early on a Sunday morning when the only traffic is the parade of Amish buggies heading to morning services. Be VERY careful and park well off the road on the Lancaster County side where the ice climbers pull their vehicles over by the icewall. A narrow walkway, not really meant to be a sidewalk for hikers and pedestrians makes crossing to connector trails on each side a harrowing ordeal for some.  I always wear blaze orange so drivers (of both horses and cars)  can see me.

Bear Island Complex, Susquehanna River, PA

The river has carved some of the deepest canyons in the East, impressive - except that they are all underwater! The flooded gorge below me is over 250 feet deep - and even deeper  upriver. Depths of up to 400 feet deep exist in an old canyon at the narrows below Turkey Hill. The Susquehanna has been flowing since long before the last Ice Age (out of eleven) and carried the gritty, roaring meltwater from receding glaciers to the Atlantic for thousands of years after each glacial period. Estimated to be over 250 million years old, this river carved it's valley down through the rising Appalachians, cutting flood plains and isolating islands across its mile wide breadth here at the Bear Island Complex. If you are afraid of heights or easily get dizzy DO NOT attempt to walk out here. But if you do, be prepared to watch for a while - and bundle up. It's frigid but so worth it!

Adult Bald Eagle below a fourth year Bald Eagle.

Since the ban on DDT in the 1970s Bald Eagles have made a tremendous comeback along the east coast from Maine to Florida and beyond. The Susquehanna provides  ideal ice-free fishing locations below its many dams. It's a great opportunity to study the different phases of coloration from juvenile first year birds through adult.On a really cold day you can expect to see large congregations.

Third year bird cowers at the approach of a bigger first year bird.

Third year bald eagles have an almost osprey-like look, complete with an eyestripe. By their fourth year the eyestripe disappears and they appear to a dirty-looking white head. Younger birds are darker and mottled underwing and across their backs. They appear larger than the older birds because of slightly longer feathers and thicker insulating down. A first year bird perched near an adult bird looks noticeably larger. Similar to hawks, eagle also display sexual dimorphism - the female is larger than the male.

Wildcat Island on the Susquehanna.

The first national eagle sanctuary was established here under Teddy Roosevelt, centered on distant (and thus inaccessible) Johnson Island. But not until federal protections under the Migratory Bird Act of 1918 were raptors afforded any legal protection at all, and not very effective protection at that as conservation officers were few and far between.

More eagles than I could accurately count today - everywhere I looked!

By 1940 the first of a series of protective laws was passed specifically for bald and golden eagles. The Bald Eagle Protection Act has since been amended ten times to increase penalties, fines, and even mandatory jail time for commerce in eagle parts, killing, and harassment. Then came DDT and a suite of chemicals developed during war time unleashed on the domestic environment as pest control in water and soil. Rachel Carson noticed the sharp decline of eagles, ospreys, and hawks in the 1950s - and the rest is history. The ban went into effect in the early 1970s and now - it's Eagle-Oh-Palooza!

A first year eagle is harassed into dropping the fish he finally caught.

The dramatic return of our national symbol to the Susquehanna Valley has been nothing short of spectacular, just in my lifetime! To celebrate I love coming out on really cold mornings (Sundays for this location on and near the bridge) when pools of open water are at a premium and eagles gather by the tens of dozens around prime fishing waters. The fishing was on! Today I stopped counting at 50 juvenile eagles and 8 adults! I wonder how many of these young birds were born on these islands? From my perch on the bridge looking down at the forest below I counted six eagle nests as well as a blue heron rookery.

First year juvenile Bald Eagle.

It's a whopping 175' to the river below.  Ice jams are common down there and what looks like shards of puddle ice stacked on the leading edge of a rocky shore, are actually as thick as fat books, clinking and crashing together as the moving water carries floes downstream. Upstream at Harrisburg the ice jams are locked in place - they won't begin to move until it warms up. When ice-out happens there, the flooding starts here. Another impressive sight from the bridge!

A hundred feet up looking down at a very cold river and its colder, deeper channel bank.

My face was pretty much frozen after an hour on the bridge, and traffic was starting to pick up so I moved down river to the Muddy Run Generating Plant. There is a fenced river walk, a little battered from flooding and lack of maintenance, but great for setting up a tripod for a scope or long lens. Gangs of young eagles argued over everything - fish, rocky perches, open water. They wheeled and chased, locks talons, stole scraps, and generally acted like adolescents.

A gang of juvenile eagles congregates near Upper Bear Island over a carcass.

I watched a long while as a third year bird tried over and over again to take a fish. On the fifth dive she grabbed it and held tight. She had a little trouble navigating the talon-filled gauntlet to find her place along a long outcrop. She tried to quickly eat her meal, but was harassed by nearby young-uns to give up her scraps. On the distant shore of an island, a deer carcass was alive with fussing eagles and she flew over to join them. Great fishers they are, but even better scavengers!

The Peavine Island Gang.

Just downstream from my river walk, a family of humans was enjoying a cold morning's fishing foray. They lined the banks with rods in hand, two big guys, two moms, and a group of kids who were more interested in exploring the ice stacks than watching their lines. I heard a shout go up and looked quickly to my left just in time to see a juvenile eagle make off with a fish one of the men had been reeling in. There was a lot of cussing coming from that group! They left after a short while, fishless, and got the family van hopelessly stuck in mud. A power plant security truck went screeching down the road, lights flashing, to go to their rescue. A little too dramatic, but I guess with the water really flowing now it was important to get them unstuck quickly. The eagle sat on a nearby rock and finished off the fish.

Battling over a fish - already dropped and back in the river!

The juvenile eagles that gather here are from all over. Wandering young eagles may spend their winters hundreds of miles from their nest homes. I suppose some of the juveniles I was watching today had come from the Canadian Maritime Provinces and New England. A friend of mine, Mike, a natural resources officer, was recently given a banded eagle that had been found dead on a highway an hour or so west of here. The band number indicated that it had been caught as a first year bird near here in 1986 - an old bird! I wonder how many young it helped raise in these parts over its nearly 30 year lifespan?

Channel edge -from a few inches deep to over two hundred feet down.

Resting Canada Geese in the middle of the torrent.

Although there are very deep channels, most of the river below the bridge is shallow and dangerously rapid, covered in thick ice floes. And eagles aren't the only birds out here resting or feeding in, on, and around the ice. Diving ducks, geese, mergansers, a loon, and dabblers rode the currents around the rocky ledges, eddying out to catch a fish or snag a freshwater clam.

Cabin on Snake Island, Norman Wood Bridge upstream.

Looking upstream from my scoping spot I could see beyond the Norman Wood Bridge three eagle nests within plain view. One very large nest was built  atop a power line tower and eagles were flying back and forth from it with nesting materials. Soon eggs will be laid and a new generation of bald eagles will be raised in the river valley. 

Black Ducks dabbling for freshwater clams.

Blacks ducks are everywhere, and if they don't pay attention, an experienced eagle will easily take one. I could see black duck feathers on a rocky ledge below the river walk and a collection of duck bones compressed into a large pellet cast by an eagle that had perched on the hand rail where I stood. A few half-hearted passes by a third year bird barely caused a flinch in a black duck flock, but the sight of a mature eagle overhead sent them skittering for the shelter of a wooded shore.

Common Mergansers among the ice floes.

Riding ice chunks, this pair was very entertaining!

It was almost 11am when the sirens at the Holtwood Dam sounded. The current quickened and with it came large ice floes dislodged from their traps along the rocky shores. The noise of crashing, grinding ice drowned out all other sounds on the river: the chortling eagles, ha-wonking of Canada geese, and the cries of gulls. To my astonishment along with floating ice came floating eagles! A playful pair of juveniles rode chunks for a few minutes until they crashed into a larger floe, then they alighted and flew upstream to another few chunks and road them down to the same place. They were clearly eagles at play and they made a fitting celebration to end my Eagle-Oh-Palooza Day!

Almost full grown and ready to find a mate!

We're waiting for eggs! Check out the Pennsylvania Game Commission's Eagle Cam live and daily time lapse as we watch the action happening at Codorus State Park thirty miles west:

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