Pennsylvania Fish & Boat Commission Biologist Report

Conemaugh River Lake Indiana County

May 2013 Night Time Electrofishing and Trap Net Survey

Conemaugh River Lake is a 639-acre impoundment that is located about 7 miles east of Saltsburg, Pennsylvania on the boundary between Westmoreland and Indiana Counties. The dam is owned and operated by the U.S. Army Corps of Engineers (ACOE) and was constructed for flood control purposes on the Conemaugh River. The ACOE has published a feature page link about Conemaugh River Lake; detailing reservoir recreational amenities and other specifics.

Conemaugh River Lake has historically been polluted by acid mine drainage, sewage, and industrial waste. However, in recent years this pollution load has been reduced and anglers are catching more and more fish. This has occurred due to the water quality improvements in the watershed over the past twenty years. Area 8 Fish Management PA Fish and Boat and ACOE survey crews have been monitoring this resurgence since 1996.

Boating is permitted on the lake with electric or manually operated boats only. However, Conemaugh River Lake has no launch ramps, so boating is limited to mostly canoes and car-top boats.

Figure 1: Aerial Map of Conemaugh River Lake

Fish populations in the lake are managed under statewide regulations. It has not been stocked with any fish species except for sauger fingerlings in 1998 and 1999. Sauger were stocked in the lake with the intent of establishing the species both within the lake and the expectation of Sauger moving upriver to suitable habitat in the Conemaugh River. However, evidence of Sauger population establishment has not been documented in these waters to date.

The 2004 Biologist Report was the last survey on Conemaugh River Lake and was a joint effort between the ACOE and the PFBC. In this survey, the lake was divided into two separate areas, the main lake and the two bays. The bays consisted of Spruce Run Bay and Aultmans Run Bay (Figure 1). This division was made based on water quality differences between the two areas. Both Aultmans Run and Spruce Run have better water

Spruce Run Bay

Aultmans Run Bay

Main Lake

quality than the main lake, which historically has been impacted by acid mine drainage. Aultmans Run Bay is accessible from Clarksburg Road (State Route 3007) off of State Route 286 on the north side of the lake, is open to shore anglers, and has a car-top launch site. Spruce Run Bay is located on the south side and can be accessed from Livermore Road (Township Road 982).

The 2013 survey included two night time electrofishing runs and two trap net deployments in the main lake and one of each sampling technique in the two bays. During our trap net survey, sampling was not nearly as effective as it could have been due to rising waters from recent rain events. One trap net from the bay sampling rolled over at night and another from the main lake captured only a few fish due to a six foot rise in water level. Therefore, the total sampling effort in the current survey was lower than the sampling effort in 2004. That being said, the 2013 sampling yielded 14 species and 185 individuals in the main lake and 13 species with 196 individuals in the bays, resulting in the best sampling catch so far at Conemaugh River Lake. Table 1 below shows the 2013 sampling breakdown by sampling technique among the two lake areas.

Table 1: Results of NTEF and TN Sampling of Conemaugh River Lake

Main Lake Tributary Bays

Species NTEF TN Size Range

(inches) NTEF TN Size Range

(inches) Banded Killifish Present 0 NA 0 0 NA Black Crappie 0 6 10-12 4 6 6-11 Bluegill 98 23 1-8 50 21 2-8 Bluntnose Minnow Present 0 NA Present 0 NA Brook Silverside Present 0 NA Present 0 NA Brown Bullhead 0 11 12-15 1 7 11-15 Common Carp Present 0 NA Present 0 NA Emerald Shiner Present 0 NA 0 0 NA Golden Shiner 0 0 NA Present NA NA Green Sunfish Present 0 NA 0 0 NA Largemouth Bass 27 1 4-21 37 0 8-17 Northern Pike 0 0 0 3 0 21-24 Pumpkinseed 20 1 3-8 19 0 3-8 White Sucker 0 1 NA 0 8 NA Yellow Bullhead 0 1 9 3 0 6-10 Yellow Perch 6 0 4-10 26 11 4-13

Figure 2: Comparison NTEF Results of Largemouth Bass Populations

The population of largemouth bass in the main lake area has continued to rise over a 17 year period. In 2013 main lake Largemouth Bass catch rates reached Big Bass Guideline bench marks. There were a total of 27 largemouth captured in the main lake with 5 individuals over 15 inches. The tributary bay areas also showed a slight increase and continue to maintain a good bass fishery. In the bay areas, 37 largemouth were collected and 6 individuals were 15 inches or larger. It is interesting to note that the Largemouth Bass catch rate indices in Tributary Bay areas were comparable in 2004 and 2013, whereas the Main Lake area index in 2013 has improved to the level of Tributary Bay areas of 1996 (Figure 2).

0

10

20

30

40

50

60

Main Lake Trib Bays Main Lake Trib Bays Main Lake Trib Bays

1996 2004 2013

LMB

CPU

E (#

fish/

hr)

Total CPUE≥ 12 in. CPUE ≥ 15 in. CPUE Big Bass Guidelines (Total CPUE)Big Bass Guidelines ( ≥ 12in CPUE) Big Bass Guidelines ( ≥ 15in CPUE)

Area 8 Fisheries Manager Rick Lorson with two largemouth bass from Conemaugh River Lake

Trap net sampling is used to assess panfish populations of most lakes. The trend for crappie is similar to Largemouth Bass. Over 17 years the population has steadily increased in both the main lake area and the bay areas. Each sample area yielded six individuals and all the main lake individuals were over 9 inches and averaged 11 inches. The majority of crappie collected in bay areas were of good size, measuring over 9 inches. Although, neither the main lake nor the bays achieved a quality crappie catch rate benchmark, the CPUE for individuals over 9 inches were relatively close to benchmark levels, with the main lake scoring 0.18 fish/hr and the bays 0.21 fish/hr (Figure 3).

Figure 3: Comparison of Trap Net Results of Black Crappie Population

Two black crappies from tap netting at Conemaugh River Lake

The trap net survey yielded positive results for the sunfish population of the lake. The total number of individuals and number of individuals over 7 inches increased from 2004 in both the main lake and the tributary bay areas. Past survey data has never met the panfish enhancement guideline benchmarks for sunfish (0.51 CPUE individuals ≥ 7inches; Figure 4). However, in 2013 the tributary bay catch rate for sunfish, including both bluegill and pumpkinseed, exceeded the benchmark for a quality sunfish fishery. The general increase in abundance has become a trend for all fish species at Conemaugh River Lake.

0

0.05

0.1

0.15

0.2

0.25

0.3

Main Lake Trib Bay Main Lake Trib Bay Main Lake Trib Bay

1996 2004 2013

BC

CPU

E (#

fish/

hr)

Total CPUE

≥ 9 in CPUE

Panfish Enhancement Guideline (≥ 9 in)

Figure 4: Comparison of Trap Net Results of Sunfish Population

The population of yellow perch has yet to make a comeback in the main lake area. Over the years only a couple yellow perch have been collected and in 2013 no yellow perch were found in the trap nets and only six individuals were captured during the night time electrofishing survey. However, the tributary bays of the lake have excellent populations of yellow perch. The trap net results from the past two surveys on the bays show a quality yellow perch fishery, since both samplings have CPUEs over 0.19 individuals over 9 inches per hour. The catch rate of nice size perch increased from 2004 to 2013.

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

Main Lake Trib Bay Main Lake Trib Bay Main Lake Trib Bay

1996 2004 2013

Sunfish (BG & PPS)

CPU

E (#

fish/

hr)

Total CPUE≥ 7 in CPUE Panfish Enhancement Guidelines (≥ 7 in)

Figure 5: Comparison of Trap Net Results of Yellow Perch Population

The Conemaugh River Lake is a direct example of how improving water quality will improve a fishery. The lake has been recovering from years of degradation from abandoned mine drainage. The 2013 results show that it may be time to switch over to a full lake sampling instead of a two site comparison sampling. Our fish management approach will now switch from a “recovering fishery” to a “managed fishery”. The main lake and tributary bays have a good density of largemouth bass and sunfish. The black crappie population is rebounding in both the main and bay areas, while the yellow perch population remains low in the main lake and relatively abundant in the bay areas.

~Prepared by Area 8 Fisheries Biologist Aide Nate Reinhart and Fisheries Biologist Mike Depew

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Main Lake Trib Bay Main Lake Trib Bay Main Lake Trib Bay

1996 2004 2013

Yellow Perch

CPU

E (#

fish/

hr)

Total CPUE≥ 9 in CPUE Panfish Enhancement Guidelines (≥ 9in)