Eclectic Echoes

Deep Sea News and Seamounts in PLoS

Dr. McClain over at Deep Sea News recently published a very readable open access paper at PLoS ONE about the potential connectedness of seamounts and nearby habitats. I love that the paper was highly accessible, both in the writing and the fact that anyone can download it from PLoS One and read it for free, especially since, in the case of Davidson Seamount and Monterey Canyon, there are significant implications on management policies, if the goal is to protect and preserve the diversity within the canyon.

A Little Closer to Home

Tim Shank and his lab have been doing a lot of work on connectivity, including genetic analysis, among and between the seamounts of the North Atlantic, especially the New England Seamounts and the Corner Rise Seamounts. Though I haven’t seen any papers yet (I believe Walter Cho is working on this for his Ph.D.) what I have been exposed to is that they are finding connectivity between seamounts and seamount areas, but it is a complex situation with very different connectivity from one species to the next, one depth to the next and one region to the next. Connectivity factors likely include reproduction and recruitment strategies, bathymetry, depth, habitat availability, and hydrodynamics (regional and local).

So Why Should We Care?

Ultimately understanding how these deep sea ecosystems are interconnected is critical for conservation and management of marine resources, including potentially many commercially important species (and the deep sea cephalopods who lay egg capsules on the deep corals, thank you very much!). It needs to be studied further to understand the extent of the connectivity. Connectivity studies have a significant number of challenges though, not the least of which is the seemingly simple task of identifying the interaction time and space scales of the relevant processes. In part these define the boundaries of populations. Identifying all the species using traditional morphological taxonomy and molecular techniques, can be a herculean task as well.

Unfortunately, the seamounts are also being impacted by deep sea fishing. Trawling across the mounts can remove entire communities of slow growing deep sea corals and the complex communities they support, potentially causing a significant effect on the deep sea coral community connectivity as well.

My Tiny Personal Connection

This last year I have been working part time with video captured on several deep sea cruises to the New England Seamount Chain and the Corner Rise Seamounts. Much of the work has been producing support video and a DVD for a variety of presentations, which I can’t present here. I can, however, finally show one piece of the package I put together, which was the last piece we did to give to the funding partners.

Your Seamounts on Fishing

The Future?

While I loved deep sea biology and invert communities before, spending many hours scouring HD video of these invert communities helped really hook me on the idea of studying them long term. As I watched the communities of inverts on the screen I had so many questions about their distribution, their physiological adaptations, limitations on growth and distribution, recruitment triggers, etc… etc… etc. I would love to be able to study these communities, the larval distribution, development and recruitment for the communities and individual species, and the ecological and anthropogenic pressures on these communities.

(Yes, I would still also love to study cephalopods and larval development and ecology within the mangroves, still lot’s of wake-me-up-in-the-middle-of-the-night questions there too!)

Notes

All footage in the piece was taken on the 2005 Deep Atlantic Stepping Stones mission, but not necessarily from the same dive or on the same seamount. The final sequence is the result of an otter door impacting and dragging across a part of the Kükenthal Seamount. An otter-door is a large metal rudder that holds the trawl nets wide open.

There is more impact footage from the mission, including trash and meters upon meters of clean parallel lines cut through communities of coral and sponges where the rollers on the bottom of the net rolled through. The otter door impact zone, however, was the starkest example of clearing the communities from the seamount in the video I surveyed, devastating damage.

Sources and Further Reading

Peter J. Auster, Jon Moore, Kari B. Heinonen, Les Watling (2005). A habitat classification scheme for seamount landscapes: assessing the functional role of deep-water corals as fish habitat. Cold-Water Corals and Ecosystems, 761-769 DOI: 10.1007/3-540-27673-4_40

Craig R. McClain, Lonny Lundsten, Micki Ream, James Barry, Andrew DeVogelaere (2009). Endemicity, Biogeography, Composition, and Community Structure On a Northeast Pacific Seamount PLoS ONE, 4 (1) DOI: 10.1371/journal.pone.0004141

Rhian Waller, Les Watling, Peter Auster, Timothy Shank (2007). Anthropogenic impacts on the Corner Rise seamounts, north-west Atlantic Ocean Journal of the Marine Biological Association of the UK, 87 (05) DOI: 10.1017/S0025315407057785