Shenango in trouble... good and bad

Is trouble brewing at Shenango River Lake?
Posted on: September 14, 2017 | Bob Frye | 0 Comments

The story of the fishery at Shenango River Lake is a good one, especially as relates to bass.

But ya might wanna get ‘em while you can.

Trouble’s brewing at the U.S. Army Corps impoundment.

Biologists from the Pennsylvania Fish and Boat Commission surveyed the Mercer County Lake earlier this summer, assessing its bass population. There was good news, different news and bad news.

The good news relates to bass. Things look pretty good where they’re concerned.

Crews electroshocked three areas. The total number of bass collected was 57.8 per hour, which is slightly above the long-term average, said Freeman Johns, a biologist in the commission’s area 1 office in Linesville.

“For a large reservoir, that’s a good number,” added Tim Wilson, another biologist there.

The catch rates per hour of fish exceeding 12 and 15 inches is also good, he added.

The fish seen included largemouths and an almost equal number of smallmouths. But the largemouths are typically larger.

Biologists handled one 20-inch largemouth, along with lots of fish between 13 and 18.

Shenango River Lake’s smallmouth population, by comparison, is dominated by fish that go 6 to 11 inches.

“We saw a few bigger smallmouths,” Wilson said, pointing to one that stretched nearly 18 inches. “But most of the trophy bass in Shenango are largemouths.”

As for the different news – neither good nor bad, necessarily – it’s about catfish.

Shenango has long had a nice population of channel catfish. That remains true, Wilson said.

It’s now also home to a growing population of flatheads.

“We got a few when we surveyed there in 2014. We got quite a few of them this year,” Wilson said. “And we saw some big ones. Giant, whopper flatheads.”

They’re an apex predator, Johns noted. But whether their presence will impact the channel cats or the lake’s panfish remains to be seen.

What is perhaps likely – and here’s where the bad news comes in – is that another fish that turned up in this year’s survey will spell problems.

Namely, alewives.

Alewife or alewives are now common in Shenango River Lake.
Alewives are a type of herring.

Alewives, sometimes called alewife, are a kind of herring. Originally a species that lived in salt water and migrated into tributaries along the East Coast to spawn, they’ve since spread into any number of freshwater lake and river systems.

Shenango is the latest water to get them.

“We’ve had them in Pymatuning Lake for quite a while. It seems like they finally made their way down the (Shenango) river and now there appears to be an established population at Shenango Lake,” Wilson said.

“I have no idea what that’s going to mean.”

There’s cause for concern, though.

For starters, once alewives get into a waterway, it’s impossible to get rid of them, Wilson said.

They can upset ecosystems, too. They often outcompete native panfish, leading to stunted populations of crappies and bluegills. That’s happened at Pymatuning and Lake Wilhelm, Wilson noted, and could prove troubling for Shenango’s popular crappie fishery.

Predatory fish can be impacted, too, though in a different way.

In the early 1990s at Pymatuning, for example, the walleyes caught averaged just 14 to 16 inches, Wilson said. But anglers got lots of them.

These days, there are still plenty of walleyes in the lake – the commission’s trap net catch this spring was its second highest ever – and they’re bigger, averaging 19 inches. But they’re also much harder to catch.

The lake’s gigantic population of alewives is the reason.

“The walleye population is actually showing signs of under-exploitation,” Wilson said. “But when they’re able to eat to their hearts content, they’re just not interested in a nightcrawler or a minnow.”

Lake Wilhelm’s bass were for a while hard to catch for the same reason.

Whether the bass fishing at Shenango River Lake is likewise headed for an era of plentiful and big but hard-to-catch fish isn’t certain.

A lot will depend on whether the alewife population explodes or merely survives at some low level, Wilson said. And there’s no telling which scenario might come true.

“There’s really no way to predict what might happen,” Wilson said. “We’ll just have to wait and see.”

Largemouth population strong at Lake Arthur
If you like catching good-sized largemouth bass, there’s another lake that it would be wise to target right now: Lake Arthur.

The 3,225-acre water that serves as the centerpiece of Moraine State Park in Butler County is home to a good number of quality bass.

Fish and Boat Commission biologists surveyed the lake earlier this summer. Final results of their work just became available.

They electroshocked three spots around the lake – by Nealy Point, the Route 582 bridge and by the dam — in an attempt to get a random sampling of fish.

They caught 301 bass, or 55.8 per hour, which is right about the long-term average, said biologist Tim Wilson.

“But where we saw a pretty big jump was in fish over 15 inches,” he said.

Crews handled 8.3 such fish per hour, “which is the highest it’s been in a while,” Wilson added.

Overall, fish 15 inches and bigger represented 15 percent of the total catch, Johns said.

The largest bass stretched a little more than 21.9 inches. Several others went 20.5.

“We did see some really nice bass at Lake Arthur. There were some really big fish, so that was a good thing,” said biologist Freeman Johns. “We just couldn’t break that 22-inch mark.”

Almost all of the bass – 296 of the 301 — were largemouths. The others were smallmouth bass. They were all small by comparison, too.

great info and article,,,, yes alewifes are kinda a double edged sword

Makes one think maybe the PennStateFishComm is hearing from some disgruntled anglers regarding the fishing at Pymie.

I remember the "baitfish" excuses for the sudden downturn of conditions at Wilhelm. However, the past few years the fishing has been on the upswing at the lake.

Mystery is, the baitfish still exist.

Only difference being, the biologist have all migrated to the SOS project. 😜

So I wonder if those huge clouds of bait fish that you'll see in Shenango suspended in 12 to 15 feet of water over a 24 foot bottom are all alewives or shad. All 3 times I've been there, there were bait balls everywhere over the channel, with some fairly good hooks below them just up off the bottom, but we couldn't buy a hit. I'm wonderin' if I should get #3 son to cast me up some rubber paddle tailed alewives in 4, 5, and 6" and see if I could score a walleye.

Shenango has been loaded with tons of Shad baitfish for years. Even with the huge appetite the Stripers have the Shad still thrive with heavy populations. Alewives are sort of new here can't say I've seen surface schools yet. It will be interesting as to what happens in the future.
 
As far as huge Flatheads they are in Shenango Lake , can't say I've caught any in the lake but I have seen photos of ones caught. 30-40 lbers seem to be around to those who know how to fish them. Would not surprise me if some 50 lbs plus Flatheads are cruising the Shenango depths.
 
Good luck Shenango is a tough lake to fish with baitfish explosions and no limit HP watercrafts. Early Spring and now ( Fall ) are your best bet.

I haven't seen a baitfish decline on Shenango in 10 years and it's loaded with Stripers and White Bass feeding on them. It's been heavy with schools of Shad almost every year I've fished it. Numerous pods of surface Shad are common sights every Spring. I'd expect Pymy won't change much either unless some disease wipes out tons of baitfish. Good numbers of baitfish are a plus for predatory fish but sure makes catching a lot harder!  Just strange to see such a quick drop in Walleye catch rates this year.   

I just passed over the reservoir not more then a hour ago. Surprised to see the water level looking like normal summer pool.

Couldn't see if the boat docks were pulled at the rec area. Vegetation on the rt18 causeway so overgrown. That use to be a pretty sight while crossing the lake.

Good question about that oder you find to be so strong Captain. As much as the sluices were used this summer, I'd have to wonder if the oder would be coming from them.

Don't know about Pymie Brock, haven't fished there since early May. In fact, haven't fished anywhere since May. Excuse me (self pity party(😟)) OK all better now.

I would liken that smell to the oder of a piece of old black pipe natural gas line. Not that I'm insinuating anyone (we know) goes around sniffing old gas pipe. But it ain't like smelling roses either.

With those thoughts fresh in mind I now have to wonder, how the hell do I come up with this stuff???

Stupid old gas pipes.

the odor is a natural action, result of geosmin blue green algae and bacteria.

Use Geomins in a sentence??

I can't even pronounce it!!!