Monday, Oct. 5, 2009
A day on the cruise with Laurel Hiebert (Bunker Hill, Blossom Gulch and Madison schools)
Sea floor at Vioska Knoll
Today was the last day of the cruise – the end of a great adventure. I was really fortunate today since I got to go on a second dive – to a place called Vioska Knoll, which was truly the most beautiful place that I have ever been. At the bottom, we landed in a vast field of white anemones and stalked white sponges, waving peacefully in the gentle current. We headed up a large hill (or knoll), towards towering coral colonies. Amongst colonies of white corals, we found stalked barnacles that resembled gooseneck barnacles, but were light brown and almost translucent. Besides the white corals, we also found black corals, which grow like trees underwater and can grow for thousands of years. The oldest black coral ever recorded was 4,265 years old! Because black coral is harvested and sold to make jewelry and it takes so long to re-grow, many black corals all over the world are being destroyed. We did our best not to disrupt this ancient undersea coral forest.
After the dive, students presented on projects that they had been working on over the last few weeks. I will tell you a little about one project that I was working on:
Deep Sea Clams Living on Tubeworms
We were interested in knowing whether larvae from deep sea animals can make their way from the deep cold water to the warm shallow water to feed. One way to find out is to see if they have enough energy to swim up thousands of feet. We measured the amount of oxygen that larvae use as they swim to help us figure out how much energy the larvae use each day. In tiny glass bottles, we put larvae from sea stars and tube worms that we raised from animals we collected in the sub. We recorded the amount of oxygen in the bottles using a sensor connected to a computer. Every few hours, we checked the oxygen level in the bottles to see how much energy the larvae had used. We ran the experiment at two temperatures: at deep sea temperature and at warm shallow water temperature, since larvae will use up more oxygen in warmer water. We’re working up the data now.
It was really exciting to hear about the projects of all of the other students onboard. We brought up many tubeworms from the bottom, and some of them have clams living on top of them. Recently, it was discovered that these clams feed on the eggs of the tube worms as they are released. Some students in the class found out that tube worms with clams have more eggs than tube worms without clams. We don’t know if the clams can choose a good worm to live on (one that would make lots of food) or if the tubeworm is trying to get the clams full so that the rest of the eggs can be released into the water.
In the evening, we had to pack many of the animals and larvae to take back to Oregon. Into eight large coolers, we packed up all sorts of animals, our treasures from the deep:
- bushes of tube worms
- a number of large crabs
-“snot worms”, which are pink segmented worms that live in mussel beds
-stalked barnacles from today’s dive
-white corals
-snails that were found living on the corals
-white egg masses from snails that are attached to tube worm tubes by thin stalks
-ribbon worms that are found living in crab egg masses
-egg masses from crabs, to feed the ribbon worms
-larvae from sea stars, tubeworms, ice worms and mussels
Back in Oregon, many of us plan to continue our studies of the deep sea with the animals that we bring back. They will live in a cold room at the temperature of the deep sea (8 to 12 degrees Celsius). We have lots more to learn about how they behave, reproduce, and survive at the bottom of the ocean.