Sunday, May 16, 2010

South Beach Marina Walkabout - May 2, 2010

Spending time walking the docks at the South Beach Marina situated below the Yaquina Bay Bridge yielded clear examples of an invasive bryozoan new to our surveys-Cryptosula pallasiana. Readily accessible on the bottom of floats, it competed for space with Botrylloides violaceus.

B. violaceus demonstrates remarkable resilience to adverse environmental conditions with mature colonies two feet up in the air at low tide here on pilings and on rocks at the first jetty finger west of the bridge. A later recreational dive much further west, beyond the turnaround along the south jetty, showed the botryllid to be common not only in the crevices subtidally but out on the rock faces as well, despite the swell and surge in this exposed location. Colonies could also be found on suitable substrate out on the river bottom.


No comments:

Post a Comment