Susquehanna now THE flathead river
Harrisburg — Pennsylvania’s got a new catfish king, like it or not.
Now the question is what to do about it.
Flathead catfish, the largest species found within Pennsylvania, are native to the Ohio River drainage. They showed up in the Susquehanna River in 2002, though.
Pennsylvania Fish & Boat Commission biologists labeled them an “invasive species” in the river system then.
Now? They’re booming in the Susquehanna, and biologists are looking at them in a new way.
“Once they’re well established like they are, they’re probably going to be resident in the system,” said Geoff Smith, the commission’s Susquehanna River biologist. “We’ve come full circle in house. We’ve kind of accepted that they’re here now, and we’re determining how to address them as a species to manage.”
Evidence of how well the fish are doing in the Susquehanna can be seen in the agency’s list of the “biggest fish of 2013.” The list – which relies on fish reported to the agency through its Angler Awards program – ranks the top five fish, by weight, for more than 30 species.
In 2006, the list’s top four flatheads all came from rivers in western Pennsylvania. That was the case with the top five fish in 2007, the top five in 2008, and three of the top five in 2009.
That same year, a Susquehanna flathead showed up on the list for the first time ever, though. The river put one more on the list in 2010 and 2011, too.
In 2013, though, the Susquehanna accounted for four of the five biggest flatheads. The smallest of the four weighed 41 pounds, 2 ounces, while the largest – and the largest reported anywhere last year – weighed 47 pounds, 1 ounce.
By comparison, just one of the four biggest fish last year came from the species’ native range in western Pennsylvania, that being a fish pulled from the Beaver River.
That’s likely the trend of the future, said Bob Ventorini, the commission’s biologist for the “three rivers” around Pittsburgh.
Western Pennsylvania was home to the state flathead record until 2006, when a bigger fish was pulled from Blue March Spillway in Berks County in 2006. Three rivers anglers have been trying to “bring it back home” ever since, he said.
He’s not optimistic they’ll succeed.
The three rivers are home to old flatheads. Biologists pulled a 33-year-old fish from the Allegheny near Highland Park, and a 32-year-old fish from the Monongahela.
The oldest on record anywhere in the country was 34 years old, and Ventorini thinks the Pittsburgh area might give up a fish that tops that.
“I think, with our continued sampling, we’re going to continue to find old fish, and maybe one older than that,” he said.
But a fish bigger than might come from the Susquehanna? That’s a different story, he said.
“It might happen. I don’t know, it might,” Ventorini said. “But I’m not too sure.”
That’s because when a non-native species first enters a new system – as with flatheads in the Susquehanna – they tend to “go gangbusters,” he said. Populations explode and fish grow faster than they do otherwise, he said.
“When a species like that moves into a system, and they don’t have any natural predators or diseases or parasites to keep them in check, they tend to population-wise and in terms of individuals get very large very quickly,” Smith agreed. “We’ve seen that documented all up and down the East Coast.”
In the Susquehanna, the fish seem to be feasting primarily on gizzard shad, but they’ll eat anything they can get their mouths around, he added.
“And they have a big mouth,” Smith said.
Anglers seem pleased with the flathead surge. Smith said a popular fishery has sprung up on the Susquehanna.
Biologists aren’t sure about the long-term implications of the fish being in the river, however.
“It’s really hard to say what the end point is going to be for big flatheads in the Susquehanna. It’s going to be evolving as we go. We’re not sure how it’s going to turn out,” he said.
One thing he does expect is that big flatheads will continue to come from the river.
“I’m pretty sure that the next [state] record is going to come from the Susquehanna,” Smith said.