Tuesday, August 18, 2009


I’ve been involved with WSM since 1989, getting more active in the past few years, after dropping out for a while. I work out of my home in Fairbanks, Alaska. The middle of Alaska seems a strange place for a marine invertebrate specialist to live, but Fairbanks was historically the science research center in Alaska. This relative isolation from others in the field of malacology- though not from other marine biologists-makes it important and rewarding to connect through professional memberships and annual meetings.

A self-employed zoologist, specializing in marine mollusks, I offer identification and analysis for environmental assessments, biodiversity surveys, and zooarchaeology. I have over thirty years experience identifying marine mollusks and other invertebrates from the north Pacific and Arctic.

For the past 10 years I have extended my projects to include identifying freshwater macrofauna for environmental monitoring and biodiversity surveys. It is a typical boreal/arctic adaptation to be a generalist and opportunist.

It is interdisciplinary projects those that involve collaboration, that are the most rewarding. One collaborative project has been describing the Late Pleistocene/early Holocene fossils associated with the landscape south of the Bering Glacier. I was fortunate to be invited by Anne Pasch, an emerita professor of Geology from the University of Alaska Anchorage first to help identify the fossils and fragments, then to participate in two field seasons at the Bering Glacier camp. Gail Irvine, a USGS scientist has also joined us as co-author.

Located east of Cordova, Alaska, Bering Glacier and its surroundings has been the site for extensive research. The glacier is several miles inland from the Gulf of Alaska. A large proglacial lake is situated between the glacier and the low forelands between it and the Gulf of Alaska.

The rapid retreat of the 1994-95 glacier surge margin provided unusual conditions in which invertebrate skeletons were deposited on outwash surfaces as entire valves or as fragments of delicate parts.

Our work during several field seasons resulted in an extensive collection of mollusk and other invertebrate shells from Holocene deposits adjacent to the ice margin of the Bering Glacier. Four localities provided the largest number of shells, and we chose those for analysis. We considered the preferences for depth, habitat and feeding class and found consistent differences among them.

Benthic infaunal organisms dominate one site, whereas the other three are dominated by intertidal or shallow subtidal species characteristic of mixed substrates.

What we are showing through this ancient fauna is that an irregular shoreline with a variety of substrates, depths, existed north of the current terminus of the Bering Glacier. The organisms clearly had to be transported south from points of origin to the north. Therefore, the Bering Glacier must have been in a retracted position 13,000 to 7,000 years ago and marine conditions prevailed 30 or more kilometers north of the present coastline. Our report will be included in a monograph on the Bering Glacier and its environment, which we hope will be published early next year.

Nora Foster

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