What’s a Wachapreague?

Heading north to Virginia (and our base of operations at the VIMS Eastern Shore Lab, ESL) was one of the easiest, in terms of travel and packing. Though maybe not the coolest ride around, a minivan doesn’t have 50 lb (23 kg) weight restrictions!

I got to bring along a different sidekick, our grad student, Ben, who had been busy helping keep the ship afloat in Charleston. Not sure four sites in four days, fast food and 4 am reveilles was a better alternative to a windowless lab!

The Delmarva Peninsula (composed of Delaware, Maryland, and Virginia) on the eastern side of the Chesapeake Bay, is an area rich in history and a culture built on the agricultural and seafood productivity of the region. The Virginia portion of the peninsula is a narrow strip of land that crests between the ocean and bay.

delmarva map

A tale of two seaweeds

A tale of two seaweeds

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4am wake up calls and sink mud are made a little easier with sunrises such as this

4am wake up calls and sink mud are made a little easier with sunrises such as this

While furiously sifting sediment, peeking at phenology and testing out Songza moods, I left Ben to manage while I took some time to talk to Dr. Richard Snyder, the new director of the ESL. Upon his arrival in June 2015, he set up a molecular facility at ESL enabling the processing of samples onsite.

At the same time, the Virginia Tech Agricultural Experiment Station in Painter, VA has developed a molecular biology program for food safety concerns under the direction of Laura Strawn. Previous to these recent efforts, molecular biology support was not available in this region. A molecular biology lab at ESL will enable resident research as well as provide support for visiting scientists. True to the region’s nature, the foci of this regional capacity for molecular biology will be seafood/marine and agriculture/terrestrial.

We also chatted about Dr. Snyder’s research. Not only is he maintaining his work on Gulf of Mexico microbes, he is also embarking on genetic analyses of Virginia bay scallops (Argopectin irradians).

Mapping the distribution of Archea, Bacteria, Ciliophora and Foraminifera in the Northern Gulf of Mexico following the BP oil well failure has used molecular methods to determine community structure. A recent publication from this work described the occurrence of multi-trophic level microbial communities at the sediment water interface on marine muds of the outer shelf and slope of the area.

A core taken by a multicoring device from 1500 m depth showing the intact sediment-water interface. © Joseph Moss, CEDB, University of West Florida

A core taken by a multicoring device from 1500 m depth showing the intact sediment-water interface.
© Joseph Moss, CEDB, University of West Florida

This fragile zone has been missed by benthic and plankton scientists. This omission has in part been the result of the difficulty of obtaining samples of deep water boundary layers, but also a bit of scientific myopia.

Dr. Snyder and his colleagues have now documented the active and very complex microbial communities which are likely found all over the deep sea benthos, countering an assumption that the deep sea sediments are relatively depauperate of eukaryotic microbes.

The team used primers targeting ciliate protists. Rather than sending only the unique cloned rRNA sequences, they chose random clones (95 per sample) to sequence. This approach enabled the team to preserve some indication of abundance for community structure analyses.

Seventy percent of the 215 unique OTUs at a 97% similarity threshold did not match known species at the family level or higher. Of those that did match, a majority were known benthic species, genera or families from shallow water. One of the efforts moving forward will address the 70% unknowns to improve the online databases by isolating single cells for morphological analyses coupled with single cell PCR for the 17s rRNA sequence.

Bay scallops, Argopectin irradians, were once common to the Atlantic coastal bays, supporting both recreational and commercial harvests, but are now closed in most areas for harvest due to low or missing populations.

© Rebecca Turner, VIMS-ESL

Bay scallops © Rebecca Turner, VIMS-ESL

The population in the Eastern Shore of Virginia coastal bays disappeared after loss of eelgrass, Zostera marina, in the 1930s. Bay scallops have been absent from this system for 70 years.

Efforts by VIMS have restored grassbeds and an effort to restore the scallops is underway, supported by the hatchery at ESL spawning and raising scallops for release.

Allan Curry, VIMS-ESL

17 day old scallops © Allan Curry, VIMS-ESL

An annual survey of the grass beds has shown an increase in the numbers of scallops surviving in the wild, now in the millions over 4,000 acres of grass.

The original broodstock for this effort came from two small batches of scallops imported from NC. Inbreeding depression and the overall genetic diversity of the population are of concern. Researchers are starting to compare the brood stock and the wild captured individuals with other populations along the Atlantic and Gulf of Mexico coasts.

Their genetic targets are a highly variable segment of the mitochondrial genome accompanied by 16 or more microsatellite loci for determining genetic diversity. The first successful PCR reactions for the scallop mitochondrial sequence this fall have certainly ushered in a new era for the ESL.

If you are interested in conducing field work at ESL or about the research efforts, please contact Dr. Richard Snyder (rsnyder@vims.edu).

Thanks, once again, to Dr. Snyder, Sean, Stephanie and all the other researchers and staff at ESL!

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About Stacy Krueger-Hadfield

I am a marine evolutionary ecologist interested in the impacts of seascapes and complex life cycles on marine population dynamics. I use natural history, manipulative field experiments and population genetic and genomic approaches with algal and invertebrate models in temperate rocky shores,estuaries and the open ocean.
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