One of the wonders of the world happens each spring on our beaches. With an act of timing that only Nature can provide, horseshoe crabs climb up the beach to spawn and shorebirds pause in their migration to feast on the horseshoe crab eggs. A good place to start in your search for more information about this phenomenon is http://www.virtualbirder.com/vbirder/realbirds/dbhsc/index.html. 

Here is a simplified explanation of the event. At high tide, especially at the spring tides following the full and new moons, male and female horseshoe crabs form "trains" with a female in the lead and one or more smaller males attached behind. These crab groups then come up onto the beach, the female lays and buries the eggs and the male(s) fertilizes them. Gulls and the higher waves uncover many of the eggs which get into the water and are deposited on the wrack line on the beach (see the report of May 9, 1999 for a picture). Birds of many varieties, including millions of migrant shorebirds, spend their spring days feasting on the eggs.

Lower Township has placed signs along the beach to explain the phenomenon. Our top left and middle pictures show those signs in Town Bank. The top right picture shows an undulating group of sanderlings feasting on horseshoe crab eggs on a May morning. At the lower left we see a female horseshoe crab helpless on her back. Females are larger and their front legs terminate in a "scissors" type of claw. In the lower middle picture we see a smaller male. The males have a "grabber" type of claw at the end of their front pair of legs. At bottom right is an upended couple. The male is tenaciously hanging onto the "pegs" at the back of the female's shell. Males also have the "pegs" which allows for longer "trains" of crabs.