First day of diving
September 28, 2012
It was a chilly, grey morning as we left Moss Landing Harbor for six days on the R/V Western Flyer investigating deep-sea gelatinous animals out in Monterey Bay with Steven Haddock. A two-hour steam took us out 20.5 nautical miles to our first dive site of 2,100 meters depth.
Early in the dive we thought we saw a fangtooth, Anoplogaster! Unfortunately, it swam away as soon as the ROV slowed down to take a closer look. But fortunately, we record video of our entire dive mission, so I will be able to go back and review it later to see if it really was this rarely seen deep-sea fish.
It takes the remotely operated vehicle (ROV) Doc Ricketts about an hour to descend 1,000 meters, so in just over two hours we reached the seafloor. Due to schedule restraints we only had time for a very brief look around the bottom and one benthic animal collection. Then we began to slowly ascend back up to the surface, collecting on the way, over the next seven hours. Steve and his research collaborators are primarily interested in animals that live in the midwater, so this is when the dive really started getting interesting for them.
Several of the animals we saw during today’s dive:
One of the scientists onboard, Stefan Siebert a postdoctoral fellow working with Casey Dunn at Brown University, was very excited at the number and variety of siphonophores we encountered today. This is a group of very poorly known colonial jellies that Steve and the Dunn lab are currently collaborating on, along with Philip R. Pugh at the National Oceanography Center (United Kingdom). Pooling resources with MBARI enables Stefan to collect these fragile gelatinous animals alive and relatively unharmed using our advanced ROV technology. In the past, deep-sea organisms were typically brought up in net trawls and these fragile animals did not fare well. The scientists are trying to understand how these creatures are organized by looking at colony formation on the morphological and the molecular level. These details are difficult or impossible to get from trawl-caught animals that have been preserved in jars.
During this cruise Stefan is looking at Apolemiid siphonophores which have been reported to grow more then 20 meters in length and happen to be quite common in Monterey Bay. Currently, there are only three species described in this group worldwide, but data from the team’s recent research efforts estimate there are at least eight undescribed species in Monterey Bay alone! Stefan’s preliminary data indicate a deep evolutionary split within the group and two distinct types of colony organization.
Today’s dive went smoothly and we collected many interesting animals for the scientists to observe in the lab back up on the ship, in an effort to further understand the amazing biodiversity in the deep ocean.