So a guy in North Carolina reels in his line, thinking maybe a crappie or a bass or a catfish was wriggling on the other end – I don’t know what they expect to pull out of North Carolina rivers, but I’d bet serious dough he wasn’t expecting to yank a piranha from the water. Yet, that’s what came ashore, with its little razor-point teeth snapping at whatever was handy, in this case the angler’s knifeblade and not his fingers or toes. Years ago I encountered piranhas, at a safe distance, in the Amazon. That is where piranhas belong, in distant jungle rivers, where National Geographic or the Discovery Channel can film them stripping the steak off a hapless cow. Let us hope that the piranha that was caught in North Carolina was a solitary fish, tossed there by some misguided soul who had been keeping the piranha as a “pet.” Let us hope the piranha was not the advance scout for some vast school of piranhas following the warming ocean currents north. Let us hope our misguided soul, if there was one, didn’t dump a breeding pair of piranhas into that river, or a pregnant female that had already laid her eggs, sowing a piranha population in that river. Let us hope -- fervently, now -- that we never catch a piranha at Upper Dam. Say "Amen."

And yesterday my pal Trout Boy sent me the following Associated Press dispatch dated July 12:

Alarmed by reports about an invasive algae found in the Connecticut River, biologists from Vermont and New Hampshire will meet tomorrow with representatives of the U.S. Fish and Wildlife Service and river groups to make plans for combating it, authorities said yesterday. At issue is the spread of Didymosphenia geminata, also known as didymo and "rock snot," which has been found in two locations of the White River and in northern reaches of the Connecticut River, which separates Vermont and New Hampshire. The microscopic algae result in thick mats on river and stream bottoms in infested waters. The algae can stick to fishing gear, boats and boots and can live in car trunks for weeks.

There is no known treatment.

Invasive species. From milfoil in Maine ponds, to piranhas in North Carolina, to "rock snot" in the White River, to smallmouth bass in the Rapid River, invasive species are changing our world, and not for the better.

My friend TWBII e-mailed to tell me that he had taken his young son, TWBIII, fishing in the Wild River the other day and that they had caught several smallmouth bass. Smallmouth bass!? Out of the Wild River, a beautiful coldwater trout stream that comes tumbling out of the White Mountains and joins the Andro at Gilead!? I thought, “No! No! Say it isn’t so!” Then I opened the accompanying digital photo and breathed a huge sigh of relief. What they had caught were suckers. TWBII is a Land Cruiser guy, not a fish guy, thank goodness.