Giant Isopod
Tiny crustaceans threaten coastal marshes needed for salmon. An army of tiny crustaceans in the tidal waters of Coos Bay is slowly chomping away at shorelines, exacerbating shoreline erosion and threatening marshes needed for salmon recovery. An Oregon Institute of Marine Biology graduate student, Tim Davidson, hopes his study of the isopod Sphaeroma quoianum, the marine equivalent of the wood louse, will help coastal areas combat the nibblers before they bore too many trenches. The isopod is a cousin of the pill bug, or “roly-poly,” found in basements and gardens throughout America. It has infested Coos Bay’s waters since the late 1980s, he said. They are native to Australia and New Zealand and have been in U.S. bays and salty rivers along the West Coast for the last 150 years. Davidson started studying the crustacean two years ago after he stumbled across an RV-size piece of insulating foam, presumably from a floating dock, bobbing in the bay. It was riddled with thousands of tiny tunnels.
It made him wonder: How many of these little nibblers were in the area?
Last week, he donned knee-high boots and plunged his fingers into the murky marsh cliff side near Haynes Inlet. “Here, here,” he said excitedly, “All of these little interconnected tunnels” … his voice trailing off. A few feet behind him rested two grassy islands, 2-by-3-feet, he believes broke away from the mainland due, in part, to the chomping isopods.
The critters measure about a centimeter and a half long, and Davidson refers to them as the “little guys,” but he said he wouldn’t mind seeing them exterminated.