Description:
Dramatic changes, such as sea ice loss, are projected to occur in Arctic ecosystems over the next century. Understanding how the Arctic’s living resources, including its vertebrate species, are responding to these changes is essential in order to develop effective conservation and adaptation strategies. Arctic species that are adapted to these extreme environments are expected to be displaced, in part, by the encroachment of more southerly species and ecosystems. A total of 965 populations of 306 species (representing 35% of all known Arctic vertebrate species) were used to generate the Arctic Species Trend Index (ASTI). For the first time, an index that provides a pan-Arctic perspective on trends in Arctic vertebrates is available. The Arctic Species Trend Index (ASTI), like the global Living Planet Index (LPI), illustrates overall vertebrate population trends by integrating vertebrate population trend data of an appropriate standard from across the Arctic and over the last 34 years (with 1970 as the baseline). This index not only gives a composite measure of the overall trend of Arctic vertebrate populations, but can also be disaggregated to display and investigate trends based on taxonomy, biome, region, period, and other categories. These disaggregations will ease the identification of potential drivers of these trends. Over time, tracking this index will help reveal patterns in the response of Arctic wildlife to growing pressures, thereby facilitating the prediction of trends in Arctic species.