Boring Polychaeta—Indicators of Climate Change in the Late Holocene on Adak Island (Aleutian Islands)

Mussel valves of Mytilus trossulus Gould, 1850 with polychaete borings attributed to the ichnogenus Maeandropolydora Voigt, 1965 were found in a kitchen midden of an ancient Aleutian site on Adak Island (Aleutian Islands). For the first time, a pattern of changes in the degree of damage to mollusk valves by boring worms, depending on climate change, is revealed. An increase in the number of borings coincides with the expansion of warm-water boreal and low-boreal benthos species into the coastal ecosystems of the island, as was shown previously.