With another spawning season about to begin, horseshoe crabs appear to be hanging on in Maryland's coastal bays, despite limited habitat for their annual reproductive reunion.
Volunteers tallied 23,105 crabs last year, roughly the same number counted in 2010, the Maryland Coastal Bays Program reports.
The annual horseshoe crab spawning congregation on the Delaware shore is closely watched, because the ancient sea animals' eggs provide food for shorebirds, particularly red knots, which stop over there to rest and refuel during an epic 9,000-mile migration north.
While the Delaware spawn peaks in May, horseshoe crabs crawl ashore in Maryland's coastal bays about a month later, the survey shows. And all but about 2,000 of them did so on Skimmer Island, just north of the Route 50 bridge.
The little island near Ocean City had been a prime breeding site for colonial nesting waterbirds, including Black Skimmer, Common Tern, and Royal Tern. But it's been eroding, and many birds have abandoned it. Last year, though, the state Department of Natural Resources managed to restore the island and its nesting habitat, using sand dredged from boating channels.
For more on the coastal bay horseshoe crab survey, go here.