Friday, April 27, 2012

Field Trip to South Cove

The Pacific Northwest is a particularly rich location to experience the biodiversity of marine life.  Spring is when many species reproduce making it an excellent time of the year to study embryonic and larval development of marine invertebrates. A point of interest is the South Cove of the Cape Arago headland as it offers students here at the OIMB an opporunity to observe and study a diverse array of organisms.  On April 24 at 8:30 a.m., with our gear in tow, we left for the South Cove to catch the -0.3 foot low tide at 9 a.m.  By van we made our way six miles south of the OIMB campus down Cape Arago highway to look for particular species of brooding bryozoans. 

Sticking close to more experienced students and our instructor Svetlana, I saw many interesting species including this morning sunstar, Solaster dawsoni, being held up by my classmate Ashley (left). Other common species of the South Cove intertidal zone we observed include the worlds largest chiton, Cryptochiton stelleri, commonly known as the gumboot chiton, the worlds largest sea star, Pycnopodia helianthoides, commonly known as the sunflower seastar, and a model organism for developmental biologists, Strongylocentrotus purpuratus, commonly known as the purple sea urchin, to name a few. After two hours in the intertidal, we headed back to the lab to study our specimens. In addition to finding the brooding bryozoans we were looking for, we found many other interesting species that we will study in class. 

A rather noteworthy member of this menagerie pictured in the center of the glass dish is the veiled chiton, Placiphorella velata. It is a rare find because this species typically occures in the very low intertidal or subtidal. Unlike most chitons which graze on algae, this predatory chiton waits for small crustaceans and worms to wander under its veil and rapidly (less than a second) lowers the hood to trap its prey. It then swallows the smaller bits whole or uses its radula to scrape and break apart parts of larger prey.

1 comment:

  1. Matthew,
    This was a excellent blog on the class search of the tidal pool. The specimens that the group collected were unique. All the years that I have search at low tide along the coast of Maine I have never come across any of these samples. Great and informative blog.