Domoic Acid and Long-Headed Polar Bears: Using Archaeological Sites to Study Marine Species and Ecosystems over Time

Abstract

A recent analysis of gastrointestinal content from a mummified ring seal recovered in 2016 at the Walakpa archaeological site (Jensen et al. 2017) has yielded evidence of domoic acid. The seal is known to have been taken in the mid-1940s, thereby demonstrating that it is not a new phenomenon in the Chukchi Sea. Histopathology provided no evidence of parasites, including metazoan and protozoa. Three other seals recovered in 2017 are also being studied.

The same site was also the source of a very large morphologically distinct polar bear skull, which raised questions of a possible subspecies (Stimmelmayr et al. 2017). Ongoing DNA analysis has ruled out brown bear admixture. Another morphologically similar cranium was recovered from Walakpa during the 2017 field season.

The Arctic is changing rapidly, and there is much concern over the effects of those changes a number of Arctic marine species, and on Arctic marine ecosystems in general. Scientific observations span a very limited period in the Arctic, less than 40 years in some cases. One way to address this would be to extend the period of observation, but the situation is urgent.

The two cases highlighted above illustrate one solution. Archaeological sites with good organic preservation are valuable resources for paleoecological reconstruction, with potential similar to other paleoenvironmental proxy records. The sites often are located at or near places that are occupied today, thus providing locally relevant long-term data. They usually incorporate the same species that are important for subsistence and food security today, so that management-relevant information on how changes affected those species can easily be gathered. New advances in radiocarbon dating, in chemical and isotopic techniques, as well as in DNA studies (e.g. aDNA and sedaDNA) make the range of information that can be recovered and questions that can be addressed ever larger.