Key Findings 3

Climate change is emerging as the most far reaching and significant stressor on Arctic biodiversity. However, contaminants, habitat fragmentation, industrial development, and unsustainable harvest levels continue to have impacts. Complex interactions between climate change and other factors have the potential to magnify impacts on biodiversity.

The life cycles of many Arctic species are synchronized with the onset of spring and summer to take advantage of peaks in seasonal productivity. Earlier melting of ice and snow, flowering of plants, and emergence of invertebrates can cause a mismatch between the timing of reproduction and food availability. In addition, warming sea temperatures in some areas has led to a northward shift in the distribution of marine species, such as some fish species and their prey. These changes have been implicated in massive breeding failures for some seabirds, and subsequent population declines.

Arctic biodiversity is impacted by factors outside the Arctic, including the long-range transport of contaminants through air and water, habitat changes along migratory pathways, and invasive alien species. Increasing contaminant loads have been documented in some polar bear subpopulations, possibly as a result of dietary shifts due to declining sea ice. Red knots are highly dependent upon a limited number of key stopover and wintering sites making them vulnerable to habitat changes occurring outside of the Arctic.