April 15, 2014
Delawareans know all too well what happens when non-native species take hold.
Consider the invasions of brown marmorated stink bugs; Asian lady beetles or an oldie but biggie: the giant marsh reed Phragmites australis. They pretty much take over home, yard and marsh.
So it's no wonder that scientists thought the worst when the Asian shore crab – a penny-sized creature with distinctively striped legs – showed up on the rocks at Townsends Inlet near Cape May, N.J., in 1988.
But it turns out, at least in the limited, rocky habitat along the Delaware and Maryland coast, these shore crabs – which were once so abundant here – haven't outpaced the natives, after all. In fact, what Charles Epifanio, the University of Delaware Harrington Professor of Marine Science, and a graduate researcher found was that the tables turned on the populations of the native versus the non-native crabs in the decade after shore crabs dramatically outnumbered native mud crabs.