Arctic Biodiversity Trends 2010

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Species

Arctic Biodiversity Trends 2010

Population/ecosystem status and trends

Although studies of the status of char populations in Arctic regions are generally lacking, some assessments exist for non-Arctic nations and their findings may be applied to Arctic populations. Unlike their southern counterparts, char populations in the Arctic generally appear to be mostly healthy, although this in part may simply be due to greater numbers being present and/or inadequate information. For example, in the Arctic regions of nations with natural populations of Arctic char, it is likely that no populations have gone extinct (information interpolated from Table 1, p. 114 in [9]). However, significant extinctions have occurred in more southerly regions (e.g., 12 of 258 known populations in Scotland and 30% of the known populations

in Ireland have gone extinct [10]), despite these being in more remote areas of these countries. This is not to say that Arctic populations are unstressed. Rather, several examples of stressed char populations are known for the Arctic particularly near to communities (e.g., for the Canadian Arctic: Dolly Varden, Big Fish River [11]; Arctic char, Hornaday River [12]), especially where over-fishing perhaps combined with habitat changes has resulted in local population collapse. Assessments of trends for chars tend to be population specific, episodic, and of short duration. Widespread geographic comparisons and assessments of status are

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Figure 6.2: (A) Arctic char, Salvelinus alpinus (L.) (B) Dolly Varden, Salvelinus malma (Walbaum) (C) Lake Hazen dwarf benthic form Arctic char (D) Lake Hazen small form Arctic char (E) Lake Hazen large form Arctic char.