Anthropogenic Sound and Under-Ice Soundscapes

The increase in anthropogenic sound in marine ecosystems is well-documented and is a growing concern; however, fewer studies have examined how man-made sound permeates under-ice environments. In polar regions, sea ice historically provided respite from anthropogenic activities as ice played havoc with submerged or above ice equipment, and subsequent seasonal curtailment of shipping, coastal construction, and natural resource extraction led to quieter winter soundscapes. Similar changes occurred in higher latitude freshwater lakes, as ice formation stopped recreational boating, the main source of anthropogenic sound. Larger lakes, such as the Laurentian Great Lakes, also underwent seasonal curtailment of shipping. However, climate change is impacting the extent and duration of ice, leading to longer shipping season and new routes through previously inaccessible seas. On freshwater lakes, tracked snow vehicles, ice roads, and ice fishing (i.e., motorized augers and icehouses) add new sources of anthropogenic sound to previously pristine winter soundscapes. Under-ice soundscapes, especially regarding anthropogenic activities, represent a tiny fraction of aquatic anthropogenic sound studies. This chapter will examine the geological, biological, and anthropogenic contributions to both polar and northern latitude freshwater lakes to better understand how anthropogenic sound is impacting these environments.