A Holocene Seabird Extinction in Maine: The Great Auk

Abstract

Seabirds are the most threatened of any living group of birds, continuing a larger pattern of elevated Holocene bird extinctions on islands and coastlines. The Great Auk (Charadriiformes: Pinguinus impennis) was found on both coasts of the Atlantic during the Holocene until its last sighting on Iceland in 1844. Far more is known about the population structure and genetic diversity of NE Atlantic populations, and the latest surviving populations were documented from the British Isles in 1834. While sightings from Canada suggest Great Auks disappeared by 1800, no systematic evaluation of extinction timing has been conducted for this coast. Determining extinction timing of the Great Auk in Maine allows a comparison to be made to populations in other areas of the Atlantic Ocean, and raises the question: was the Maine population’s fate different due to regional, cultural, or other factors? There is a single eye-witness record in the late 17th century at “Black Point”, now Scarborough, Maine. To address this gap, we compiled a radiocarbon dataset on associated material from Maine archaeological shell middens. These 91 dates from 13 sites situate the Great Auk in Maine from about 180 to 4,555 years before present. The majority of these dates are from charcoal samples, but also include shells, ceramics, and bone, and cultural contexts span the Middle and Late Ceramic Periods. To account for differences in stratigraphic control and sampling material, we assigned quality scores, and used these scores to run a sensitivity analysis in extinction timing with the GRIWM model. Disentangling the spatiotemporal dynamics of the Great Auk extinction in Maine is useful in determining how to conserve current species in decline and modern insular seabirds in Maine, such as the puffin. Future study will include new radiocarbon dating of bones as well as isotopic and morphometric analysis to unfold more chapters of the Maine Great Auk’s narrative.