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Beringian Canyon Quest Update

Dec 8, 2009
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Here's a brief, semi-annual update! Research in the Bering Sea Canyons, especially Pribilof and Zhemchug Canyon, is ongoing and underway now! These are only two of several canyons cut into the North American Continental Margin, aka the Beringian Margin. Zhemchug is the largest undersea canyon in the world, and Pribilof Canyon is an interconnected component of the Pribilof Domain -- an oceanic province, or system, that supports an extraordinary diversity of marine life in the Pribilof Island vicinity.

The multbeam survey of Pribilof Canyon was completed in June by Terrasond-Mt.Mitchell, using NOAA funds. The survey covered depths from about 200 to about 2,200 meters. Immediately following the canyon survey, we headed north and spent two long days surveying areas within king crab essential fish habitat (EFH). Both areas covered also had documented seabed features important for larval king crab -- the feature is called "Shellhash", and is basically piles of bivalve and gastropod shells. The multibeam system onboard the Mt. Mitchell for covering this depth range was the Kongsberg EM 710. We collected and archived both bathymetric and "backscatter" components of the acoustical data. Awesome seafloor maps and other results of these surveys will be posted online soon.

More results from the 2007 submarine expedition are also forthcoming, and will be online here and elsewhere very soon. Specimens were sent to labs globally, and some were worked on in Alaska. The extended "team" has identified species in the canyons -- some of which are new to science, and many are range extensions -- species found in places never reported previously. I have been working on various aspects of the canyon project, including examining stable carbon and nitrogen isotopes of selected species to explore foodwebs of the benthos, species identifications, biogeographical mapping of specimens within the canyon geological setting, and examining microfossils to explore paleoecology of this portion of the Bering Sea shelf edge, also known as the Beringian Margin.

Much more is ongoing, and I shall endeavour to post results from various investigators in the near future. Meanwhile, I have been sharing highlights of some of our work through dozens of presentations at Alaskan schools from Barrow to Juneau, as well as public presentations from Point Barrow to Boston Aquarium. Discussions with students on St. Paul Island, in Seward, Anchorage, Juneau, and elsewhere have been inspirational, and generated new ideas on how to examine these canyons from a scientific and technological perspective.

To those of you that have been emailing me, apologies for slogging on the blogging. Will post more here and on www.alaskadeepocean.org very soon.

The University of Alaska posted an evening presentation I gave on the canyons last year on utube: http://www.youtube.com/watch?v=CvEGfVtZleE

Some links to other media write ups on the canyons are here and elsewhere on this blog.

http://www.gi.alaska.edu/ScienceForum/ASF18/1880.html

http://www.juneauempire.com/stories/091607/loc_20070916020.shtml, http://www.sciencemetropolis.com/category/lecture-notes/

Return to the Beringian Canyons!

Jun 7, 2009
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01 June 2009 Anchorage to Dutch Harbor, Unalaska Island, Alaska

PRIBILOF CANYON SEAFLOOR MAPPING EXPEDITION 2009

During our submarine expedition to the Bering Sea Caynons in 2007, we conducted 14 dives in Pribilof Canyon and 4 ROV surveys. We distributed our dive effort around the canyons at roughly equidistant intervals, to cover the depth ranges reachable in the deepworker submarines -- a maximum of 630 meters. The ROV could reach 1,100 meters. At that time, we navigated using the best available bathymetric (seafloor depth) information available.

Most of that data was based on relatively crude surveys from the 1960's, making it difficult to plan dives to precisely hit our depth and seafloor feature targets. OK, we were essentially "flying blind"! Our current mission is to map the canyons for purposes of future submarine research navigation and for many other purposes.

Pribilof Canyon and the connected Pribilof Domain waters surrounding the Pribilof Island Archipelago are recognized for their unique, highly productive characteristics by scientists in many disciplines --- geologists, fisheries biologists, oceanographers, benthic ecologists, foodweb specialists -- concur that the region's physical and biotic attributes are outstanding relative to the shelf break and shelf regions nearby. How unique and quantifying facets of the canyon geo-bio setting are challenges we continue to address.

Since so many marine scientific disciplines rely intimately upon modelling, and modelling requires a fundamental understanding of the geomorphology of the canyons, Dr. Dave Scholl and I underscored the importance of obtaining fine scale bathymetric data for the canyon system during our address at the Marine Science Symposium (Anchorage, January 2008). Dave, who first mapped the canyons with Dave Hopkins in the late 1950s, was startled to find that very little mapping effort has been conducted in that area in nearly 50 years!

Finally, a team with the right stuff has been assembled to map

the canyon.

St. Paul Islander, Candace Stepetin and I are focusing on biogeographical exploration of Pribilof Canyon. We will be examining areas already surveyed visually by submarine and ROV in previous years to observe the depth profiles, geomorphology of the area, and to ascertain whether the backscatter component of the sonar returns being used on this survey are capable of detecting seafloor features documented by sub.

The team is gathered in Anchorage on weather hold ... awaiting our flight to Cold Bay and westward to Dutch Harbor this afternoon.

I'm Back!

Dec 16, 2007

Many weeks have passed since I returned from the Bering Sea Canyon Expedition, but not one day has gone by that I haven't dealt with some facet of the cruise observations, data, or sharing information through discussions and presentations. As promised, I will provide initial findings of the research on as information from our international team of ecologists, biologists, geologists, biogeographers and taxonomists becomes available.

Here are a few links to articles and radio pieces about the expedition.

Anchorage Daily News September 2007

http://www.adn.com/news/environment/story/9283284p-9197791c.html

Juneau Empire September 2007

http://www.juneauempire.com/stories/091607/loc_20070916020.shtml

Anchorage Daily News: Relevations from the Deep

http://www.adn.com/life/alaskana/story/9463582p-9374837c.html

SCIENCE magazine October 2007

http://www.sciencemag.org/cgi/content/full/318/5848/181a#AFF1

http://www.sciencemag.org/cgi/content/full/318/5848/181a/F1

University of Alaska Geophysical Institute Science Forum

Revelations from a deep sea canyon, by Ned Rozell Fairbanks, Alaska