The time has come for mid-Atlantic fans of the red knot, a migratory shore bird that is proposed for endangered status under the federal Endangered Species Act, to head out to watch the birds feed on horseshoe crab eggs and the like at their favorite Delmarva and Delaware Bay spots. During the species' migration to and from the Arctic tundra and southern Chile and Argentina, many of them stop along the Atlantic coast to belly up to a feeding frenzy. Birdwatchers' online sightings reports announced the red knots' presence near Lewes, Del., on May 2 and 3, and yesterday on High's Beach near Cape May, NJ. According the interactive ebird.org map of red knot sightings since 1900, other than the world-famous hotspots around the Delaware Bay, red knots also can be found near Ocean City and on Assateague and Chincoteague islands, with a lighter prevalence along the Chesapeake Bay's shores – including around Baltimore region. The U.S. Fish and Wildlife Service's proposed listing of the red knot comes after a population crash in the 2000s alarmed birdwatchers and scientists. Commercial horseshoe-crab harvesting is now managed to help preserve the red knot's stop-over diet, and scientists have come to believe the greatest threat to the bird comes from climate-change effects, such as the loss of shoreline habitat due to sea-level rise and higher-intensity storms battering the coastlines on which they rely.