Seamounts 2007, Day 2-3

Our second day at sea was brought to close on much calmer seas. We again dove on Pioneer
Seamount, the northernmost station during our cruise and approximately parallel with San
Fran Cheezy. We continued to explore the volcanic cones. In contrast to the deeper
habitats on day 1 where corals dominated, the shallower regions we visited today were
characterized by dense sponge meadows. What corals did appear, they were stunted in
growth possibly related to the rather fragile volcanic substrate. We found more of the
new nudibranch, Tritonia sp., and addittionaly collected a Neptunea.

Today, Day 3, we moved on to Davidson Seamount further south, approximately parallel with
the Big Sur coast. Davidson Seamount will likely soon be added to the Monterey Bay
Marine Sanctuary and has received an increased amount of attention both by scientists and
the public. This is my second time to visit Davidson and I was no less in awe this time
around. Previously, my work focused on the southern most region of Davidson. Today we
dropped down on the northern end, a potentially younger volcanic region. Lava pillows,
tubes, and domes dominated the flanks. We eventually transversed the flank and explored
around an extinct lava pond. Most of the pond and flanks were either void of life or
possessed very low densities of organisms. Although speculative, its is likely that
these regions experience little current and thus settling larvae rarely make it to this
area. Alternatively, low current speeds may prevent many organisms that survive on
filtering the water for food to flourish here. The highlights of today’s dive were
capturing length video of both a chimera and a blob sculpin swimming above the seafloor.
From here we moved onto the southern most cone at Davidson and explored the coral gardens
and sponge meadows that Davidison is known for. I lucked out again today capturing
another of the, apparently not so rare, nudibranch. Tomorrow, we steam south to the
Patton Escarpment, our deepest dives during the expedition.

Great photos from the ROV dives can be seen at Seamount 2007 website previously mentioned.