Horseshoe Crabs and Birds - Perfect Together
From the windy fringe of shoreline that stretches along the western edge of Cape May County into Cumberland County, the Delaware Bay sparkles like the fabled Cape May diamonds in the spring sunshine.
Acres of tidal wetlands, dotted by tiny communities named Reeds Beach, Pierce's Point, Port Norris and Shell Pile are home to migratory birds, horseshoe crabs, butterflies and other wildlife. Visitors here wear binoculars, not bikinis, and are more interested in sightings than suntans. Because of its configuration and location, the Cape May Peninsula is a major stop-over spot for migrating shorebirds and wading birds, second only to the Copper River Delta in Alaska.
The area hosts more than 20 species of birds, including red knots, ruddy turnstones, sanderlings and semipalmated sandpipers, whose arrival coincides with the horseshoe crab spawning season. During the full moon high tides in May and June, millions of female horseshoe crabs come ashore to lay more than 100 tons of eggs, re-enacting a ritual that has been taking place for hundreds of millions of years. Considered living fossils, horseshoe crabs existed about 500 million years ago. With their prehistoric features, these marine inhabitants are millions of years older than dinosaurs and, interestingly, are more closely related to spiders and scorpions than other members of the crab family.
Horseshoe crabs are found from Nova Scotia to Mexico but by far the largest population is along the Delaware Estuary. This same area is also a migratory corridor for shorebirds, some from as far away as Tierra Del Fuego at the very tip of Chile, who travel 10,000 miles to their breeding grounds in the Arctic. The birds arrive along the bay after a non-stop, 2,500-mile flight from South America, at the same time the female horseshoe crabs come ashore to spawn. The eggs of the horseshoe crab are a protein-rich food supply for these birds as they wing their way north from places in South and Central America. Amazing as it sounds, virtually the entire red knot population gathers on Delaware Bay beaches in May to gorge themselves on the eggs of the horseshoe crab before continuing their flight.
The celebrated concentrations of shorebirds and breeding horseshoe crabs can be seen along the bay from North Cape May to Fortescue, Maurice River and other points in Cumberland County. Many of the spots are accessible from Rt. 47, which winds from Middle Township in Cape May County into Cumberland County. There are plenty of resources available for the novice naturalist or for anyone who needs directions, suggestions and guidance.
For more information, refer to the Cape May Bird Observatory.