joe reynoldsSanderlings (Calidris alba) are small sandpipers, about seven inches tall and weighing in at just two to three ounces.  These plump little shorebirds are often seen around New York Harbor from late summer through late spring skittering up and down a beach like a quick moving wind-up toy being chased by endless waves. Along the way the birds will stick their beaks into the sand to probe for food within the wet sand, mostly sand crabs, young razor clams, marine worms, and other small invertebrates.

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Sanderlings are one of the most common shorebirds in both New York and New Jersey. Yet, seeing one with a tag or a band on its leg is a sporadic and interesting sight, especially during the summer.

As first reported in my blog, New York Harbor Nature, I spotted a single sandpiper foraging for food near the tip of the Sandy Hook peninsula, close to the entrance of New York Harbor. It was an adult Sanderling in breeding plumage with two noticeable bands on its pure black legs – a lime green tag on one leg and a small silver band on another. Where did those unique leg bands come from?

To find out I immediately reported my sight at, a website run by the USGS Patuxent Wildlife Research Center. Scientists here provide numbered leg bands to bird banders and help manage vast databases of bandings and recoveries in both the United States and in partnership with the Canadian Wildlife Service of many different species of birds.

It took several weeks, but the other day I received an email from the USGS with information about where the shorebird was banded. Similar to what the Birding Dude reported in his blog about the sight of a banded Sanderling at Breezy Point, NY in 2016, my Sandy Hook, NJ bird was banded as well around Bowers Beach, Delaware Bay.

​To be specific, the Sanderling was banded last year, on May 23, 2016 near South Bowers Beach, in Kent County, Delaware, located right along Delaware Bay, and south of Bombay Hook National Wildlife Refuge. The bird hatched in 2014 or earlier. Unfortunately, it’s sex or where it hatched is unknown.

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Like many other shorebirds of New York Harbor, Sanderlings do not nest or breed here. They make long winged journeys to breed in the High Arctic, far above the Arctic Circle on remote rocky, treeless islands, often near lakes or ponds. Sanderlings will make pit stops around New York Harbor to feed and rest as they migrate in-between breeding sites and over-wintering areas.  

Few species equal their worldwide wanderings. Sanderlings are long distance migrants and are found around the world on sandy coastal beaches. They often make long nonstop flights between important stopover sites, and frequently return year and year to the same wintering, breeding, and stopover sites. Flying from southernmost limits of South America to nest in the High Arctic can be a journey of over 8,000 miles.

According to a 1990 ornithological study written in The Auk about the migration routes of Sanderlings in the Americas by J. P. Myers and others, they found that Sanderlings migrating north from wintering sites along the coast of southern Brazil and occasionally the Pacific coast of South America often travel along the Atlantic coast of the United States. Southbound migrants from breeding sites in the High Arctic often make stopovers on the Atlantic coast on their way to coastal wintering sites in South America. Yet, the migration pattern for Sanderlings is complex and repeatedly widespread.

It seems safe to say the tagged Sanderling I spotted in July winters somewhere down south on a temperate or tropical sandy beach from the Carolinas, Cuba, Caribbean islands, or along the coast of South America, such as in Brazil, Chile or Peru. In the spring, it migrates in a large flock with other Sanderlings northward. They will make a stop-over somewhere along Delaware Bay to rest and re-fuel before making another long winged flight to nest in the High Arctic. Once the breeding season has ended sometime between mid-July to mid-August, the bird will move southward, making a stop someplace around New York Harbor to rest and re-fuel here too, before reaching its wintering area sometime in October or November.

It’s a crazy whirlwind, cosmopolitan life for a little shorebird. Yet it's not easy being a world traveler. Sanderlings are experiencing serious declines since the 1970s, as much as 80% of the population. Sanderlings rely heavily on a small number of re-fueling areas during migration, and destruction of these areas can seriously affect the population.

Wildlife scientists are now trying to link migratory rest sites with wintering and breeding areas into one system towards protecting these critical re-fueling areas throughout the Americas. Success, in part, hinges on people reporting the sight of tagged or banded birds.  If you find a banded bird please go to to report your finding with the band number, or numbers if the bird has more than one band.

Banding birds provides a good deal of information about the migratory movements and lives of birds. We know from banding birds, for example, the oldest living Sanderling on record was at least 13 years and 5 months old. It was found in 2016 at the Wetlands Institute in Cape May County, NJ.

To view more pictures, video, or stories of wildlife around Sandy Hook Bay, Raritan Bay, and Lower New York Bay, please visit my nature blog, NY Harbor Nature at