Dams and pollution are destroying precious life forms – forever. We can all work locally to undo the damage and restore the life we can still save in our rivers, creeks and streams.
San Marcus gambusia
Clearly, the world’s biodiversity crisis is most acute in freshwater ecosystems, and all of us need to look around us for actions we can take locally. Along the Hudson River, we have an enormous opportunity we’re just beginning to seize. We can remove obsolete, forgotten dams, numbering more than 1,700, that were built along streams feeding the Hudson centuries ago that are fragmenting habitat, inhibiting genetic diversity, and quietly stifling life in the water every single day.
As we take stock of our achievements, we need to understand the scale of loss.
The number of freshwater organisms that have gone extinct in the past 100 years in the United States is now approximately 150 species. Millions of years of evolutionary adaptations made these creatures finely tuned for very particular habitats – but did not prepare them to withstand human destruction of their waterways. In my opinion, the total destruction of the Louvre and all its contents would not compare to the loss of these species and their alleles that are permanently lost from the gene pool.
Below are the 11 freshwater species listed by USFWS that will never ever be seen alive again:
Fish
Maryland darter / Dave Neely
• San Marcos gambusia (fish) – Range: Texas. Reason: dewatering of rivers.
• Scioto madtom catfish – Range: Ohio. Reason: agricultural runoff.
Mussels
• Yellow-blossom pearly mussel – Range: Tennessee & Alabama. Reason: dams and pollution.
• Upland combshell mussel – Range: Georgia, Alabama & Tennessee. Reason: dams and pollution.
Tubercled-blossom pearly mussel / Cincinnati Museum of Natural History
• Tubercled-blossom pearly mussel – Range: Ontario south in 7 states. Reason: dams, pollution from coal mining, logging, and agriculture.
• Turgid-blossom pearly mussel – Range: Alabama, Tennessee, and Arkansas, Reason: dams
• Stirrupshell mussel – Range Alabama & Mississippi, Reason: dams, river channelization, and sedimentation.
• Southern acornshell mussel – Range: Georgia, Alabama, & Tennessee, Reason: dams.
• Green-blossom pearly mussel – Range: Tennessee and Virginia, Reason: dams.
• Flat pigtoe mussel – Range: Mississippi and Alabama, Reason: dams, canals and locks.
It’s difficult to overstate the damage caused by dams. The Chinese paddlefish, up to 21 feet long, was officially declared extinct in 2020, and its loss can be attributed to a single hydroelectric dam, the Three Gorges Dam on the Yangtze River. The Three Gorges Dam also caused the extinction of the Baiji, one of only four species of freshwater dolphins. All other freshwater dolphins species are now critically endangered and threatened with extinction, mostly due to hydroelectric dams. The American paddlefish is also threatened throughout its range, due to overexploitation and damming.
All freshwater megafauna (weighing more than 66 pounds) have declined by 94 percent in the last 50 years. Migratory fishes have declined by 76 percent in the same time period.
Let’s face up to the damage done, and prioritize the life we still can save.