Week 2 - Nudibranchs, and Molluscs, and Crabs, Oh My!

Monday, April 8

We started this week off by going out to several spots on the mud flats around the HMSC campus and helping Dr. Sylvia Yamada collect and record captured Carcinus maenas, and five other species of crabs including Cancer magister, Cancer antennarius, Cancer productus, Hemigrapsus nudus, and Hemigrapsus oregonensis. We collected eight traps by the pump house docks that had been placed over the weekend. After taking record of the species we found there, any C. maenas were kept for Marine Science Day and all other species were released. We then headed to the exposed mudflats near the aquarium where we collected about 20 traps of three different types. A couple of the traps had fish in them, and some had as many as eight C. maenas. The exciting find was a Cancer magister that had molted in one of our traps. The size difference between the crab and its molted exoskeleton was significant. The reason for this change in size is a process known as ecdysis, during which they form a new exoskeleton beneath their old one, absorb nutrients and minerals from their old exoskeleton, then back out of their old shell and then swell with water while their bodies are soft. This leaves them vulnerable until their carapace hardens. Lucky for this little guy, we found him and meant him no harm.

Tuesday, April 9

Unfortunately, our hike to Cascade Head was cancelled after being postponed due to inclement weather. Instead of this trip, we decided to get through our last two lectures on the Phyla Echinodermata and Chordata. We were then given the rest of the day to study for the upcoming finals and work on our “favorite marine invertebrate” papers and presentations.

Wednesday, April 10

First thing in the morning we had donuts and coffee with the staff, where we were able to purchase some awesome HMSC Student Organization swag. The rest of the day was available for work on our presentations for the evening meeting and wrapping up our other assignments. The presentations went great! Everyone had a great time feasting on cheesecake, cookies, and mussels, while enjoying marine invertebrate game shows and presentations. Some crowd favorites included Geoduck Jeopardy, Gumboot Chiton Bingo, and Blue Ringed Octopus Family Feud, with the last of these pictured below.

Thursday, April 11

On Thursday, we had multiple study sessions for both the lecture final and the lab practicum. Everyone then spent the rest of the day studying as hard as they could for the next day. Some even pulled late hours at the library, trying learn as much of the material as possible. Here we found Emily, Ashley, Hannah, and Megan all working incredibly hard and filling whiteboards with knowledge.

Friday, April 12

Today was the day of the final exam and lab practicum. We had all studied hard and it was amazing to see how far we had come in the last week. We learned the natural history of the Oregon coast, discovered the defining traits and anatomy of the invertebrate phyla, and memorized the scientific names of ~55 organisms we collected throughout the previous week. The lecture final exam began at 1pm and was followed by the practicum, so we had all morning to cram those last few scientific names into our brains. The exams were over by 4pm and after we cleaned up the lab for the next session we were ready to enjoy our weekend of freedom. The sun was even shining after two straight weeks of rain!

Saturday, April 14

Saturday was Marine Science Day at Hatfield, and the campus was full of people excited to learn about the center, marine science, and the programs offered at Hatfield. All of the labs and classrooms had been transformed into demonstrations for visitors. About six of us came out to volunteer in the wetlab, and it was a fun and rewarding experience to be able to teach the public some of the things we had learned in class and in the field. We had consolidated the organisms we collected into four tanks and released organisms that we had multiples of. The visitors were very interested in what we had to show them, and there were some very curious kids who were eager to see the organisms. We were able to show visitors how to identify different crab species, particularly the invasive green crab species we learned about earlier in the week with Sylvia Yamada. Other big hits were the nudibranchs, echinoderms, and skeleton shrimp. It was a fantastic way to wrap up the invertebrate unit and demonstrate how much we had learned, by teaching it to the public.