Arctic Biodiversity Trends 2010

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Indicators at a glance

Arctic Biodiversity Trends 2010

Indicator #07 PAGE 45

Across the globe, invasive species have caused extensive economic and ecological damage and are a significant factor in the endangerment and extinction of native species. As native species are lost so too are the potential cultural, subsistence, and other human uses of that biodiversity. Although biological invasions are less studied in the Arctic, invasive species have been reported in both aquatic and terrestrial environments. Arctic lands and waters have thus far remained largely intact and less invaded than more temperate environs, but are increasingly at risk of invasion. In terrestrial ecosystems, many invasive plants have been recorded along limited road systems and other altered habitats. There is less information on marine ecosystems but they are believed to be at increasing risk from shipping and offshore development activity. As climate change alters Arctic ecosystems and allows more human access and activity, the number of invasive species and the extent of their impacts in this region are likely to increase. Invasive species (human-induced)

Indicator #08 PAGE 49

The Arctic Species Trend Index

The Arctic Species Trend Index (ASTI) was developed to provide a pan-Arctic perspective on trends in Arctic vertebrates. Tracking this index will help reveal patterns in the response of Arctic wildlife to growing pressures and thereby facilitate the prediction of trends in Arctic ecosystems. A total of 965 populations of 306 species were used to generate the ASTI. Overall, the average population of Arctic species rose by 16%between 1970 and 2004, although this trend is not consistent across biomes, regions, or groups of species. The terrestrial index shows an overall decline of 10%, largely a reflection of declines (-28%) in terrestrial high Arctic populations such are caribou, lemmings, and the high Arctic brent goose. Declines in terrestrial high Arctic populations may be partly due to the northward movement of southern species in combination with increasing severe weather events in the high Arctic and changing tundra vegetation. Although both freshwater and marine indices show increases, the data behind the freshwater index is currently too sparse in terms of species and populations, while the marine index is not spatially robust.

Indicator #09 PAGE 53

Arctic genetic diversity

Understanding genetic variation in Arctic species is critical to their conservation and effective management in this time of rapid environmental change. Genetic analyses can be used for a variety of purposes, from determining the history of species dispersal and diversification to evaluating the conservation status of a species of concern. As the range and abundance of species declines, the genetic variability needed to respond to novel challenges will also be reduced. A significant increase in our efforts to build temporally-deep and spatially-extensive specimen archives is needed. These specimens will provide a baseline of environmental conditions and, when combined with mapping of genetic structure, will be crucial for both effective recovery efforts for declining species and for predicting species response in the face of climate change and other human impacts in the Arctic.