The Birds of South Beach

Although large concentrations of birds occur on South Beach at all seasons, most birders are attracted by the exceptional numbers of shorebirds and terns that roost on the beach at high tide during the warmer months. Many birds fly over from North Monomoy to roost here, particularly during the higher lunar tides. From mid-July into the fall, the number of shorebirds present at high tide routinely exceeds 10,000 individuals, and during the peak of migration in late July and early August may approach 20,000 birds, with daily lists in excess of 15 species typical, and 25 or more species possible. (When a passing raptor or jaeger flushes these masses of birds, a mind-boggling display of avian mayhem often ensues!)

Short-billed Dowitcher (midwestern race hendersoni)

Black-bellied Plover, Semipalmated Plover, Red Knot, Sanderling, Semipalmated Sandpiper, Dunlin, and Short-billed Dowitcher are the most abundant species, each typically peaking at 2000+ individuals. Less numerous, but still common, are Piping Plover, American Oystercatcher, Greater Yellowlegs, Lesser Yellowlegs, Willet, Ruddy Turnstone, White-rumped Sandpiper, and Least Sandpiper. Hudsonian Godwits used to peak at a hundred or so individuals from mid-July through mid-August, though now rarely number more than 75 birds; this is one of the best locations in the country to see this scarce bird. At least 25 species of shorebirds occur annually, and rarities such as Red-necked Stint and Curlew Sandpiper have been found with some regularity in recent years. Piping Plovers nest commonly on the beach, and during August and September small groups of post-breeders/migrants, occasionally numbering 40–50+ birds, can be found (usually on the outer beach at the southern tip). 

American Oystercatcher

Several pairs of American  Oystercatchers also nest, and post-breeding flocks recently have numbered upwards of 200+ birds. Rounding out the nesting shorebirds, a few pairs of Willets recently have become established, primarily in the vicinity of the small patches of salt marsh, and by late July, augmented by migrants, can number over 200 individuals. Among these are typically 10-20+ of the western race, inornatus, considered by some to be a distinct species.

Small numbers of Least Terns often nest on the beach, though to date with minimal success. Although Common Terns have not yet nested, a huge colony (8,000+ pairs) has developed on the north end of South Monomoy just a few hundred yards to the west, and these birds are much in evidence from early May into the early fall. Flocks numbering hundreds to thousands of birds routinely loaf on South Beach, particularly when the tidal flats are exposed. A few Roseate Terns can often be found during the spring and early summer, and during the late summer many hundreds of this species may stage in the area prior to migrating south. Although Arctic Terns no longer nest in the area, an occasional adult drops in during spring migration, and during the summer one-year old birds (the so-called “portlandica” plumage) are usually present, their numbers ranging from a few individuals to several dozen in some years. Small numbers of Black Terns and Forster’s Terns also are regular from mid July into the fall, and Black Skimmers are seen with some regularity. Rarer species such as Royal, Sandwich, and Gull-billed Terns occasionally appear, and in 2002, New England’s first Elegant Tern spent most of August in the area.

Pelagic birds are another feature, the area being one of the better on the East Coast for land-based observations of these ocean wanderers. As is typical elsewhere, the presence of seabirds here is frustratingly unpredictable, as often as not the ocean being distressingly devoid of avian activity. At times, however, hundreds, occasionally even thousands, of storm-petrels and/or shearwaters are in evidence, some very close to shore. Wilson’s Storm-Petrels can be common from early June through the late summer. Sooty Shearwaters are most likely during the early summer (early June through early August), with Greater Shearwaters predominating during the late summer and fall (July into early November). Manx Shearwaters can occasionally be picked out among their larger congeners, and a few Cory’s Shearwaters show up in some years. Thousands of Northern Gannets transit the coast during their spring and (especially) fall migrations, occasionally coalescing into spectacular feeding frenzies. Black-legged Kittiwakes and Razorbills can also be numerous during the late fall and early winter.

Immature Parasitic Jaeger

The large concentration of terns in the area attracts jaegers, primarily Parasitic, from late July into the late fall, and these pelagic pirates occasionally put on spectacular displays of their aerial skills. They are not at all hesitant to cross directly over the beach in pursuit of an unfortunate victim, often providing birders with unsurpassed views; few places on the East Coast afford a better opportunity to study their myriad plumages or enjoy their rowdy behavior. Indeed, these tireless rogues can become a nuisance at times, constantly flushing not only the tern flocks, but the shorebirds as well, frustrating one’s efforts to find and study some calidrid waif among the roosting masses – more than one observer has watched helplessly as a stint or some other potential vagrant vanished into a swirling cloud of panicked birds!

From late fall through the winter, sea ducks are often impressively abundant. Common Eiders and Red-breasted Mergansers are typically most numerous, but all three scoters as well as Long-tailed Ducks can also be abundant. Both Common and Red-throated Loons are common migrants, the latter often passing by the hundreds on some days late in the fall.

Northern Harriers have nested on the beach, though not for several years, and regularly course the dunes at all seasons. From mid-September through November (less commonly in the spring), Peregrine Falcons and Merlins routinely wreak havoc among the lingering shorebirds, and during flight years a Snowy Owl or two may lord over the winter beach. Large flocks of Snow Buntings move through during November and early December, while small groups of Lapland Longspurs often consort with the Horned Larks in the fall. The “Ipswich” race of Savannah Sparrow is also a regular transient at this season. When northwest winds displace migrant songbirds to the coast in the fall, a few may seek temporary shelter in the sparse dune vegetation.

Although birds may be the visitor’s primary focus, it is impossible not to notice and delight in the hundreds of Gray Seals that spend the warmer months feeding in the adjacent waters. Coyotes also inhabit the beach (and have even been seen swimming between South Beach and Monomoy!), but usually manage to stay out of sight during daylight hours.