September 15, 2012 Russian benthic team
With a busy day ahead of us today, I wrote this journal last night just before our last station.
Dr. Stanislav Denisenko, Vladimir Skvortsov, Mikhail Zhukov and Aleksey Merkulyev are all from the Zoological Institute, St. Petersburg, and Stanislav and Vladimir also work with the State Polar Academy in St. Petersburg where Mikhail is a student. Together they make up the Russian benthic team. Even though they usually take their own sediment samples at different stations, they are always there to help when Jackie, Monika and I are doing grabs and cores. When they do their own sampling, they take three grabs at each station and sieve the mud to get the benthic invertebrates. Although we do the same, their methods are a bit different. While we sieve through a one-millimeter screen, their final sieve is through a silk mesh, allowing them to protect the whole animal as much as possible. After identifying the dominant species in each sample, they preserve the entire sample for analysis and identification at the Zoological Institute once they return home. Stanislav and Vladimir are looking at abundance, biomass, and diversity of species, particularly the dominant species, because it is known that nearly 50% of the total zoobenthos biomass (the mass of all animals living on the bottom) of the Chukchi Sea is from only 7-10 species, and the majority of those are mollusks. They'll compare growth rates of common mollusks from different years to possibly correlate with a changing climate. They can see a chronological record in the shells of the mollusks. By combining data from this cruise with data from other cruises and from colleagues in the US, Stanislav hopes to continue to build a model of the bottom ecosystems of the Chukchi Sea.
While on the cruise, Mikhail is also looking at sipunculids (see 9/14) for distribution and abundance. If you read yesterday's journal, you'll know that Monika Kedra who works with us, is also a sipunculid specialist. With Monika and Mikhail on board, we have nearly 20% of the world's sipunculid specialists on the cruise. Aleksey is also working on an individual project. He collects gastropods from each of the trawls and is sorting them for taxonomy and systematics.