India, Oct. 6 -- A tiny fish in Tasmania might be in trouble. These tiny fish, swan galaxias, can grow to a maximum length of about 5 inches. The Threatened Species Scientific Committee, an advisory body to the Australian government, states that the primary threat to this fish is competition and predation from alien fish. The introduction of brown trout to the island more than 160 years ago is a major culprit.

Settlers made early, scattered attempts to introduce trout and salmon to the territory starting around 1841, but the breakthrough came in 1864, when trout eggs brought across the ocean from England were successfully hatched at Plenty, Tasmania. Eventually, trout became widespread around the island's rivers and lakes. But now there ...