Ocean Sentry
(From thedailygreen.com)- The report resulted from a collaboration among scientists in the U.S., Canada and Mexico.The declines aren”t restricted to fish (crayfishes, snails and mussels are showing similar signs of stress) and the list of threats is familiar. “Freshwater fish have continued to decline since the late 1970s, with the primary causes being habitat loss, dwindling range and introduction of non-native species,” said Mark Myers, director of the USGS.
“In addition, climate change may further affect these fish.” The USGS press release did not mention the threats, but overfishing is also a problem for some fish, particularly diadromous fish like American shad and Atlantic sturgeon.
Habitat loss can come in many forms, including dams — both active hydropower projects and derelict dams with no modern use — and development that destroys stream-bank habitat or wetlands. Power plants that use water to cool condensers may also play a role in declines of some species.
“Nearly half of the carp and minnow family and the Percidae (family of darters, perches and their relatives) are in jeopardy. Fish families important for sport or commercial fisheries also had many populations at risk. More than 60 percent of the salmon and trout had at least one population or subspecies in trouble, while 22 percent of sunfishes — which includes the well-known species such as black bass, bluegill and rock bass — were listed. Even one of the most popular game species in the United States, striped bass, has populations on the list.”
(By Dan Shapley)
