For more than a century, an introduced fish has been reshaping Tasmania’s freshwater ecosystems. Now, conservation teams are building artificial barriers, clearing waterways and creating isolated refuges in an effort to prevent one of the island’s native fish from disappearing completely.
The Swan galaxias, a small freshwater fish found only in eastern Tasmania, is estimated to number about 6,000 individuals. Much of its former habitat has been lost after introduced brown trout spread through the island’s river systems, leaving the native fish largely confined to small headwater streams that trout have difficulty reaching.
