Migrant birds fly north in the spring and south for the winter, right? You might be surprised to learn that the southbound fall migration for some birds actually begins in July, in the heart of what we in North America call “summer.” Most of these July migrants are of the shorebird family of birds. These earliest migrants are actually the adult shorebirds that migrated north in the spring to Canada or the Arctic to breed. Almost immediately after their young fledge, these same adults abandon them and begin their southward migrations. The young birds are left behind to fend for themselves for a few weeks and figure out for themselves how to survive and how and where to migrate! Most of the shorebirds we see after mid-August are these hatch-year birds, riding the second “wave” of migration after their parents. How they know where to go and how to get there is one of those profound miracles of nature.
The shorebird family is a very diverse one that includes species that range from the 4-5” sandpipers (also known affectionately by birders as “peeps”) to the 26” Long-billed Curlew. The Long-billed Curlew is a western species that we do not see here on the east coast; the largest shorebird that we’re likely to see here is the 19" Marbled Godwit. The photograph at the beginning of this blog entry is a Marbled Godwit; contrast this bird with the tiny Semipalmated Sandpipers, below.
Also conspicuous on the Virginia beaches in August is the tern migration. Terns are in the same family of birds as gulls, but are generally more sleek and streamlined than gulls are. Many species sport a black cap or crest in breeding plumage that fades away as fall approaches; they are much less striking in their winter plumage. Terns are the white birds that you see flying over bodies of water with their heads down looking for small fish, then diving straight down, bill first, to catch that meal. Terns come in all sizes too, from the 9” Least Tern to the 21” Caspian Tern.
From left to right: Sandwich tern (with the yellow bill tip), Forster’s Tern, and the orange-billed Royal Tern, which is almost as big as the Caspian.
I went to Bethel Beach on August 18 in hopes of finding some of these early fall migrants, and I was not disappointed. Bethel Beach is near the town of Matthews, on the Middle Neck of Virginia, on the west side of the Chesapeake Bay. Once you get to Bethel Beach you can walk southbound along the beach until you reach a sandy "hook" where the beach ends. At the end of this hook I found five different species of terns, and several species of shorebirds. I took all the photos in this blog entry on that day; here are some more:
The shorebirds above and below are Short-billed Dowitchers, migrants along our waterways. There is a Long-billed Dowitcher too, very similar in appearance to the Short-billed and it's often impossible to tell the two apart; contrary to the implication in their names, the bill sizes overlap and cannot usually be relied upon as the only identifier. You'll find dowitchers probing the mudflats and shallow waters with their long bills, looking for food.
One of the subfamilies of shorebirds is the Plovers. They are usually easy to tell apart from other shorebirds by their smallish size, very rounded appearance and very short bills among other things. They hunt by sight, rather than by feel, as longer-billed shorebirds like dowitchers do. Below is a common migrant along our coast, the Semipalmated Plover. A plover that you might be more familiar with is its "cousin" the Killdeer, which is a permanent resident throughout North America. Killdeers are larger than semipalmated Plovers and have two dark chest stripes instead of one; they are also famous for their "broken wing" display, which they perform as a distraction if they believe their chicks are threatened.
Semipalmated Plover at Bethel Beach
Killdeer for comparison with the Semipalmated Plover.
Here are two Least Terns; as mentioned above, they are our smallest Tern, measuring about 9" from tail tip to bill tip. They are a threatened species, mostly due to loss of habitat. They nest on open beaches and sandy places, where they have to compete with humans in a mostly losing battle for habitat. Fortunately there are some nature preserves that block human access during their breeding season, which allows the terns to successfully reproduce.
The medium-sized Sandwich Terns, below, also migrate down the Atlantic coast in August. These two at Bethel Beach are mostly in their winter plumage. Note their yellow bill tips; if you can get close enough to them to see this field mark, you can make a positive identification of this species.
The Seaside Dragonlet (below) is our only saltwater species of dragonfly, and at this time of year they are abundant along the beaches. The individual below is a female; note the numerous tiny stripes on her thorax. The adult male is entirely dark blue, almost blackish in appearance.
Bethel Beach was also a fantastic spot to see Ospreys and Bald Eagles, roosting in the nearby scrub and trees or soaring as they hunted for prey.
Osprey
This bird is not yet a fully-grown adult Bald Eagle; it takes eagles four years to acquire the all-white head and tail for which they are well known.
As we move into September, the numbers of shorebirds and terns will decrease as they continue south to their wintering grounds, but numbers of other kinds of birds will increase. One of the most anticipated times of year on the Virginia birder's calendar is September, when the bulk of songbirds migrate along our Atlantic Flyway. We will soon see orioles, tanagers, flycatchers, warblers, vireos and many others moving through, and one of the best places to witness this migration is along the southern tip of Virginia's Eastern Shore. Places like the Eastern Shore National Wildlife Refuge and Kiptopeke State Park are traditional hotspots where birders gather in the morning and hope for a "fallout" of these birds. By mid-September and well into October and even November, the hawk and eagle migrations will be at their peak. I will be out there for the next couple of months as often as my work schedule and my pocketbook allow, and I hope I will find a lot of good things to share with you. Until next time, take a little time to enjoy the bountiful nature and wildlife that we are so fortunate to have here, in and near Chesapeake.
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