Overall, the largemouth bass population at Lake Somerset in 2005 was better than it was during five previous surveys since 1978 (see Table 1). The total bass catch rate of 45 bass per hour of night electrofishing in 2005 was the second highest of the Lake Somerset surveys. The catch of bass 12 inches or greater was 17 per hour in 2005, which was the highest of the survey years. The catch of bass 15 inches or greater was 6 per hour in 2005, which was the second highest recorded. The Big Bass Regulations seem to have increased the number of quality-sized bass at Lake Somerset. The biggest largemouth bass that we collected was 22 inches, 7.8 pounds.

Fisheries Technician Gary Smith with a 22-inch, 7.8-pound largemouth bass

Table 1. Catch of largemouth bass per hour of night electrofishing at Lake Somerset. Big Bass Regulations were implemented at the lake in 1998.

Eighty-one walleye were captured with trap nets and night electrofishing in 2005. The majority of the fish were legal size (15 inches or greater). The walleye catch in 2005 was lower than in 1995; however, water temperatures during the time of the survey were more favorable to capturing walleye in 1995 than in 2005. Walleye anglers were very successful at Lake Somerset in 2004 and quality-sized fish are still available in 2005. Eight of the 81 walleyes were between 24 and 29 inches.

Area Fisheries Manager Rick Lorson with a nice walleye

The muskellunge and tiger muskellunge populations at Lake Somerset were good. Eleven muskies and nine tiger muskies were collected in 2005, which was slightly lower than the catch of 17 muskies and 11 tiger muskies in 1995. Seven of the 11 muskies in 2005 were 40 inches or greater including a 46-inch, 31.4-pound fish. All of the muskies and tiger muskies in 1995 were less than 40 inches. Lake Somerset would be an excellent lake in southwestern PA to target musky and tiger musky.

Fisheries Technician Gary Smith with a 46-inch, 31.4-pound muskellunge

Only one northern pike was captured in 2005. The northern pike population in Lake Somerset has declined dramatically in the last 15 years due to winter drawdowns. The pike population at Lake Somerset in the 1970s and 1980s consisted of an abundance of sub-legal pike (less than 24 inches). The PFBC has used winter drawdowns to control aquatic vegetation in the lake. Winter drawdowns at Lake Somerset began in the late 1980s, at first every other year and now every third year. The drawdowns reduced the pike population by decreasing the amount of vegetation that the pike use for spawning. Abundant sub-legal pike have been replaced by musky and tiger musky of legal size (over 30 inches).

Bluegills, pumpkinseeds, yellow perch, and black crappies were collected in good numbers in 2005. Some quality sized panfish were present with 20% of the bluegills over 7 inches, 14% of the yellow perch and 16% of the black crappies over 9 inches. The panfish populations have improved since the 1990s, particularly black crappies. Anglers have also reported similar improvements. Gizzard shad are abundant in Lake Somerset with 1,642 fish collected with trap nets. This shad population is an excellent forage base for the larger predators. However, they also can be detrimental to the panfish by out-competing them for food. Fortunately, Lake Somerset has a relatively balanced gamefish to panfish mix.

Fishing and Boating Maintainer Dave Charlton with a Lake Somerset crappie

Several factors have led to the improvement of the panfish populations in the lake: 1) An increase in the number of predators by protecting more bass (Big Bass Regulations) and increasing the stocking rate of walleye, channel catfish, musky, and tiger musky to reduce the number of small panfish and gizzard shad and 2) A reduction in aquatic vegetation through winter drawdowns to decrease the “weedy” habitat that small panfish hide in to avoid predators.

Redear sunfish, which were stocked from 1996 to 2004, were not collected during our survey, nor have we heard of angler catches of redear sunfish. We will discontinue stocking these fish in Lake Somerset. Our catfish catch with trap nets was low, but nice bullheads and channel catfish were present.

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