Migrating Ducks Find Emergency Refuge on the Susquehanna

As anticipated, lakes and ponds throughout the lower Susquehanna basin are beginning to freeze.  Fortunately for the waterfowl thereon, particularly diving ducks, the rain-swollen river is slowly receding and water clarity is improving to provide a suitable alternative to life on the man-made impoundments.

Ice-free Susquehanna at Harrisburg, Pennsylvania
The Susquehanna, ice-free and receding from near flood stage levels last week, can presently provide suitable habitat for diving ducks and other wintering waterfowl.
A Common Merganser on the Susquehanna in Dauphin County, Pennsylvania.
A feeding Common Merganser takes a breather between dives on the Susquehanna in Dauphin County, Pennsylvania.

The deep freeze is not only impacting ponds and lakes in the lower Susquehanna valley, but is evidently affecting the larger bodies of water to our north and northwest.  During Tuesday’s snow event, thousands of diving ducks arrived on the main stem of the river—apparently forced down by the inclement weather while en route to the Atlantic Coast from the Great Lakes and its connected waterways, which are currently beginning to freeze.

Ice-free Susquehanna
Tuesday’s snowfall not only blanketed the landscape with a coating of white,…
Bay Ducks on the Susquehanna
…it prompted thousands of migrating “bay ducks” including Canvasbacks, Redheads, scaup, and other diving species to seek open water and make a forced landing.
Scaup on the Susquehanna
Scaup were by far the most numerous of the birds in the grounded flight.  The majority appeared to be Lesser Scaup.
Scaup in flight.
Scaup in flight on the Susquehanna.
Scaup, Buffleheads, and Long-tailed Duck
A mixed raft of scaup and Buffleheads seen one day after a snowstorm-related fallout of late-season migrants.  A single Long-tailed Duck, a species formerly known as Oldsquaw, can be seen to the lower left.
Scaup, Bufflehead, and Long-tailed Duck
Scaup and a Bufflehead (center) fly past a Long-tailed Duck.  Because they winter primarily in coastal waters, both of the latter species are sometimes categorized as “sea ducks”.
Ruddy Ducks
A small flock of Ruddy Ducks.
Common Mergansers
While Common Mergansers on the Susquehanna are fish eaters (piscivores), other diving ducks observed during this fallout event are primarily benthic feeders, eating plant matter and invertebrate animals collected from the river bottom.
Common Goldeneyes
A small flock of Common Goldeneyes. They, like the Long-tailed Duck and Bufflehead, are sometimes known as a species of “sea duck”.
Scaup and Buffleheads
Another mixed raft of scaup and Buffleheads loafing on the Susquehanna.
Bald Eagle
Large numbers of waterfowl attract the attention of the river’s ever-vigilant Bald Eagles.
Adult Bald Eagle
An adult Bald Eagle patrolling the area of a fallout in search of dead, sick, or injured ducks.  In addition to the victims of naturally occurring ailments, eagles find birds and mammals wounded or killed by hunters to be particularly attractive sources of food.   They can, therefore, quite easily ingest pieces of shot.  Because eagles in the lower Susquehanna valley feed as frequently in upland habitats as they do in riverine environs, use of alternatives to toxic lead shot is prudent practice in all habitat types.
Fourth-year Bald Eagle
A Bald Eagle in the first month of its fourth calendar year.   Though not yet matured to breeding age, this bird is nevertheless smart enough to be on the lookout for vulnerable or deceased waterfowl during a post-storm fallout.
Seeing Some Waterfowl
A fallout of some migrating waterfowl seldom escapes notice by members of the gasoline and gunpowder gang…
Taking Aim at Some Waterfowl
…who find their very presence an irresistible temptation to arouse their adolescent urges…
Harrassing Some Waterfowl
…to get an adrenaline junkie’s fix.

With more snow on the way for tomorrow, you may be wondering if another fallout like this could be in the works.  The only way to find out is to get out there and have a look.  Good luck!  And be good!

Common Goldeneyes, Buffleheads, and Migrating Canada Geese

Spring migration is underway and waterfowl are on the move along the lower Susquehanna River.  Here is a sample of sightings collected during a walk across the Veteran’s Memorial Bridge at Columbia-Wrightsville this morning.

At the Veteran’s Memorial Bridge, the Susquehanna was cresting this morning after recent rains and accompanying snow melt.
An overnight breeze from the southwest and calm winds during the morning hours created ideal conditions for flocks of Canada Geese to begin migrating north from Chesapeake Bay through the lower Susquehanna valley.
These three Common Mergansers and a Common Goldeneye (right) are some of the hundreds of diving ducks presently gathered on the river in the vicinity of the Veteran’s Memorial Bridge.
Common Goldeneyes and a first-winter male Bufflehead (upper right).  All of the ducks seen today in the waters surrounding the bridge are benthic feeders, diving to the river bottom to pluck invertebrates from the substrate.
A male Common Goldeneye (Bucephala clangula).
A female Common Goldeneye.
A pair of Common Goldeneyes in flight.
A pair of Buffleheads in flight.
Common Goldeneyes repositioning for another series of feeding dives.
During the morning flight, thousands of Canada Geese were seen moving north in flocks numbering about 50 to 100 birds each.  The bird in the lower right was one of thousands of Ring-billed Gulls seen headed upriver as well.
As they pass over the lower Susquehanna region, migrating Canada Geese are typically observed flying much higher than flocks from the local resident populations, often reaching the cruising altitudes of aircraft.  Aviators are always alert for flights of resident geese around airfields.  But to prevent bird strikes during days like today when thousands of migratory geese traverse the airspace, air traffic controllers can become extra busy relaying the location and altitude of potential targets to pilots flying aircraft entering areas where birds have been reported.

This is, of course, just the beginning of the great spring migration.  Do make a point of getting out to observe the spectacle.  And remember, keep looking up—you wouldn’t want to miss anything.