Pennsylvania Fish & Boat Commission Biologist Report

Conneaut Lake Crawford County

Spring 2012 Trap Net and Electrofishing Survey

Conneaut Lake is the largest of eight natural, inland lakes formed over 10,000 years ago during the last glacial episode. Located in Crawford County, and only seven miles west of the City of Meadville, Conneaut Lake covers about 930 acres and is nearly two miles wide. Anglers who frequent the lake particularly enjoy the abundant panfish population and trophy bass fishery. The Pennsylvania Fish and Boat Commission (PFBC) stocks Conneaut Lake annually with walleye and muskellunge fingerlings. All of Conneaut Lake’s warmwater sport fish species are managed under Statewide Regulations for Commonwealth Inland Waters. Shoreline fishing opportunities on Conneaut Lake are limited due to the number of private residences, boat docks, and businesses located along its shoreline. For that reason, Conneaut Lake fishing opportunities are best enjoyed by boat. Conneaut Lake is popular among recreational boaters and jet skiers who take advantage of the lake’s unlimited horsepower regulations. The lake features three boat launches – two public and one private. The PFBC maintains one of the public launches on the northern end of the lake. The other public launch – Fireman’s Beach (launch fee required), is maintained by the Borough of Conneaut Lake. The Borough’s access area features amenities that include a shoreline fishing area, beach, playground, picnic tables, and restrooms. The private launch – Nye’s Marina, is located at the southern end of the lake. This facility features 190 dock slips that anglers can rent for the summer. Nye’s Marina also provides fuel, dockside parking, picnic area and shelter, and restrooms. For more information on these and other recreational opportunities around Conneaut Lake please visit http://www.conneautlake.com/html/attractions.html Fisheries Biologists from the Area 2 office in Tionesta set five Pennsylvania-style trap nets which were deployed and retrieved throughout the week of April 16th. The purpose of our trap net survey was to evaluate the status of the lake’s muskellunge and panfish populations and to determine the success of our stocking programs. Our sampling effort consisted of 20 overnight sets (24 hour period intervals) encompassing a total 456.55 hours of effort yielding a catch of 1,285 fish representing 22 species (Tables 1 and 2).

The predominant panfish species collected in our trap nets was bluegill. Of the 663 bluegills sampled by our nets, 38% were ≥ than 7 inches. Good numbers of black crappie (141) were also sampled with 93% ≥ 7 inches and of these 16 fish were greater than 10 inches. Decent numbers of pumpkinseed (12) and rock bass (20) made up the rest of the panfish sampled. Several yellow perch were also caught but were not of quality size (< 7 inches).

Representative sized bluegill (left) and black crappie (right) collected from Conneaut Lake. Another popular sport fish among anglers in Conneaut Lake is the northern pike. This naturally reproducing population continues to thrive within the lake. Our northern pike catch was the second highest on record with a total of 21 fish. Size of individuals was equally impressive with fish ranging from 13 - 36 inches and 33% of them were of legal size (>24 inches). Most of the northern pike collected were primarily males although we also captured a handful of spent females (spawned out), signaling that the northern pike spawning was all but complete. Northern pike typically spawn at water temperatures between 46 – 53° F shortly after ice out conditions.

Fisheries Biologist Brian Ensign with a 36 inch northern pike caught in our trap nets.

Overall catches for muskellunge appear to be down at the present time. In efforts to enhance the population to previous levels, the PFBC has increased its stocking efforts over the past several years. These efforts include stocking of: larger sized fingerlings, supplemental fingerlings (when available) and in some years yearlings. Although our nets yielded only two total fish (a male and female), their size was impressive particularly the female measuring at 47 inches. Historically, based on angler reports, when muskellunge are caught in Conneaut Lake they typically are of trophy status which may explain why this lake continues to hold the state record at just over 54 lbs.

The larger of two muskellunge caught in our trap nets, a gravid female which was released to spawn.

With respect to the walleye population, since the timing of our sampling was a little late, we plan to conduct a future survey in the early spring when water temperatures are more amenable to capture. In early spring walleye, staging for spawning, move to near shore areas. This in-shore movement makes them more vulnerable to our trap nets and allows us to more reliably quantify their abundance.

PFBC WCO Deputy Dave Wetsell with a 25 inch adult walleye caught during our trap net

survey.

Conneaut Lake continues to maintain an abundant bowfin population. We captured 38 bowfin in our trapnets and several more were observed during our night electrofishing survey. Many of these fish were fairly large (over 20 inches). These prehistoric fish are native to Pennsylvania and are quite unique compared to other lake dwellers. One unique characteristic of bowfin includes this species having a swim bladder that functions much like our lungs, allowing them to obtain oxygen by gulping air. This is especially helpful during the hot summer periods when dissolved oxygen levels can be low particularly in the shallow backwater areas, often where bowfins reside. Bowfin are also an important part of the balance of fish communities, helping control the numbers of prey fish capable of overpopulating our waters, and they rarely consume other sport fish or act as a serious competitor with them for food. Anglers should not overlook this bowfin species since most are aggressive feeders, can obtain even larger sizes (up to 30 inches) and put up a spirited fight when hooked.

Fisheries Biologist Brian Ensign with a typical size bowfin caught in our trap nets at Conneaut

Lake.

Fisheries Management Area 2 staff returned to Conneaut Lake on May 22nd, to conduct a nighttime boat electrofishing survey to assess the largemouth and smallmouth bass populations. Three historical sites were sampled totaling 2 hours of electrofishing time. Historical index sites along near shore areas were targeted where a total of 68 black bass were netted. Largemouth bass were the predominate species and outnumbered the smallmouth by a 4:1 ratio. Both species produced quality sized fish, largemouth bass up to 20 inches (500mm) were collected (see Figure 1). Catch rates for largemouth bass were similar to historical averages (Figure 2) with the exception of bass greater than 12 inches (~300mm), which was the highest on record. Although smallmouth bass occur at a lower density than largemouth, their overall catch rate was also the second highest on record. In summary, the combined black bass (largemouth and smallmouth) population indicates that Conneaut Lake continues to provide a trophy bass fishery for anglers to catch presently and should remain good for the foreseeable future.

Other species sampled during our surveys consisted of silver redhorse, golden redhorse, golden shiner, and white sucker. Offspring from these are providing an abundant forage base for the larger predatory fish that inhabit the lake.

Fisheries Biologist Brian Ensign with a pair of trophy sized largemouth bass (left)

and smallmouth bass (right).

One disappointing observation regarding our Conneaut Lake survey has been a previous invasion of zebra mussels. Zebra mussels first appeared in Conneaut Lake in June 2011. Zebra mussels are detrimental to aquatic ecosystems and are therefore considered an aquatic invasive species (AIS). They are known to disrupt food chains by outcompeting native mussels and fish for food, including phytoplankton. In large enough abundances, zebra mussels can even attach themselves to the shells of native mussels, preventing opening and resulting in suffocation. Zebra mussels are generally small in size and can be distinguished from native mussels by their zebra-like shell pattern.

Zebra mussels, when prevalent, can attach to native mussels (photo courtesy of USFWS).

Unfortunately, once zebra mussels begin to reproduce and populate a waterway, it is nearly impossible to eradicate them. Other Pennsylvania waters that are infested with zebra mussels include Edinboro Lake, Sandy Lake, Conneauttee Creek (in Crawford County), Conewango Creek (in Warren County), and most notoriously, Lake Erie. It is likely that zebra mussels were spread by infected boats or bait buckets, anglers and boaters are encouraged to take every precaution to prevent additional introductions of this AIS to other Pennsylvania inland waterways. A detailed description of how anglers can clean boats, boat trailers, and other gear that retain lake water, and thus potentially harbor larval life-stages of this mussel can be found on our website at http://fishandboat.com/cleanyourgear.htm Thank you for doing your part.

Brian A. Ensign, Fisheries Biologist - Area 2