Hi Bivalve Aficionados,
Hi Bivalve Aficionados,
This article comes from “Tide Bites”, the monthly newsletter of UW Friday Harbor Laboratories. “Red rock crabs: the Dungeness’ grouchy cousins” by Sylvia Yamada and Scott Groth: read the full article at the FHL website.
Native red rock crabs (Cancer productus) are important predators on protected rocky nearshore communities from Alaska to Baja California. While they are harvested recreationally, they have not been as well studied as their commercially-valuable cousin, the Dungeness crab. Red rock crabs are abundant on semi-protected rock and boulder beaches where the substrate is composed of sand and shell gravel and where the salinity remains high. They have voracious appetites, feeding on a wide variety of species including barnacles, mussels, clams, oysters, snails, worms and sea cucumbers. Adults are highly mobile and are known to move into the high intertidal during flood tides to forage. We decided to piece together the life cycle of the red rock crab by compiling what was learned through various studies carried out on different life stages at Friday Harbor Laboratories.
from UW Today, January 12
The acidification of the ocean expected as seawater absorbs increasing amounts of carbon dioxide from the atmosphere will reverberate through the West Coast’s marine food web, but not necessarily in the ways you might expect, new research shows.
Dungeness crabs, for example, will likely suffer as their food sources decline. Dungeness crab fisheries valued at about $220 million annually may face a strong downturn over the next 50 years, according to the research published Jan. 12 in the journal Global Change Biology. But pteropods and copepods, tiny marine organisms with shells that are vulnerable to acidification, will likely experience only a slight overall decline because they are prolific enough to offset much of the impact, the study found.
“What stands out is that some groups you’d expect to do poorly don’t necessarily do so badly – that’s probably the most important takeaway here,” said Kristin Marshall, lead author of the study who pursued the research as a postdoctoral researcher at the University of Washington and NOAA Fisheries’ Northwest Fisheries Science Center. “This is a testament in part to the system’s resilience to these projected impacts. That’s sort of the silver lining of what we found.”Marine mammals and seabirds are less likely to be affected by ocean acidification, the study found.