Scientists' goal: Make the rare American shad less rare

It is that time of year: time to count the fish.

The ones traveling hundreds of miles from far-flung ocean waters. The ones heading upstream in search of a suitable space of riverbed (the Black Rock Dam in Phoenixville is always nice this time of year) to meet that special someone and lay a couple of hundred thousand eggs before leaving town.

In these next few weeks, the height of the spawning migration season, the job of counting all the fish passing through town falls to Joe Perillo. He's an aquatic biologist for the Philadelphia Water Department who runs the Fairmount Fish Ladder. That's the series of rising concrete chutes and pools that sit on the banks opposite the Fairmount Water Works. It's how the fish make their passage over the Fairmount Dam.

These days (the spawning season runs from about April to July) Perillo can be found kneeling in front of a wall-sized window in a concrete bunker at the edge of the dam, watching fish dart past. Sometimes in ones and twos and sometimes in packs so thick (30,000 to 50,000 fish pass through the ladder each season) it looks as if they're squeezing through a turnstile. Thankfully, Perillo does not have to count the fish manually. That's how it was done until the 1970s, he said. Video cameras film the fish, and a team of assistants trained by Perillo ticks them off. It takes about a year to count them all.

Passing by Perillo's underwater window are fat striped bass and schools of alewives and blueback herring. There's flathead catfish lurking in the chutes to lazily feast on herring, and there are lumbering carp that push through pooling fish like barroom bullies.

There's the occasional northern snakehead ("a python with fins," Perillo said). And like an old returning friend, there's that butterfly koi, the one with the orange swirls and very human-looking nose that finds its way year after year. Perillo's 7-year-old son has named it "Creamsicle."


Read more at http://www.philly.com/philly/columnists/mike_newall/20160515_Scientists__goal__Make_the_rare_American_shad_less_rare.html#7rUwKfJmIHOeVhUh.99


A little good news for a change. The Schuykill River was a dead river until it was dredged in the 1950s. There was so much coal in the river that the mineral rights to the settling basins were bought so that the coal could be extracted. The river became the impetus of the Clean Water Act. It's made a remarkable comeback over the decades and has became a testament that clean water and a functioning economy are not mutually exclusive.