Tuesday, September 11, 2018

Clove Lake Survey

Bureau of Fisheries Technical Brief #2018008

Clove Lake is a narrow, shallow 10 acre lake located in Clove Lake Park in northern Richmond County (Staten Island), formed in the 19th century by damming a small brook. The largest of a chain of three connected lakes, Clove Lake is popular with anglers, but all the lakes have access. Largemouth bass, sunfish, and brown bullhead are the most common species in the lake, and are most often targeted by anglers. The lake was surveyed in Fall 2017 by boat electrofishing following the Bureau of Fisheries Black Bass and Sunfish Sampling Manual (Brooking et al. 2018) to assess bass, panfish, and bullhead populations. Due to shallow water, large sections of the shoreline were unreachable and total on-time during the survey was relatively short (36 min).
A pie chart representing the percentage of Catch by Species
A total of 704 fish from 5 species were captured (common carp were also observed). Nearly 80% of those were bluegill and pumpkinseeds. Only 6 largemouth bass were captured, less than 1 percent of the total (Figure 1). The total largemouth catch/hour (CPUE) of 9.89 (Table 1) is low for similar sized lakes in New York State. However, 5 out of 6 were quality size or larger resulting in a PSD of 83.3. Adult bass relative weight was a high 126, indicating that the few bass present were in good, even fat, condition. This is not surprising given the abundant forage in the lake. In contrast, panfish were generally small, with low PSDs of 1.1 for bluegill and 0 for pumpkinseed.
The presence of few but large bass combined with many small panfish, shiners, and bullheads suggests a prey overbalanced lake. The reason, however, is unclear. Bass exploitation is low thanks to the catch and release regulation, so apparently bass recruitment is being outpaced by sunfish recruitment. It's possible that anglers are pulling bass off beds, but shoreline access is not universal and there is plenty of space for nesting bass to remain unbothered. Water levels may fluctuate, and such changes might impact bass recruitment. Excess vegetation can also inflate small sunfish populations, but it can also aid young bass. Still, future management considerations should include nutrient control as a matter of general lake health. Another possibility is to include stocking smaller bass to aid recruitment, but without identifying the reason for low recruitment that might be wasteful. The last survey of this lake occurred in 2009 when bass PSD was much lower but overall numbers of all species were higher. Regular surveys may provide more insight into this system. For the moment, while the potential to catch a quality bass exists, a more balanced size profile is desirable for the angling population in this public park.
Table 1. CPUE per size categoryi for each species
TotalTime (h)CPUE(fish/h; Standard Error)
All sizesAge-1≥Stock≥QualityPreferred
Largemouth bass
Golden shiner700.61116(24)----
Brown bullhead680.61112(36)53(21.5)48(24)1.7 (1.5)-
Bluegill2840.61469(121)20(12)152(24)1.7 (1.5)-
(i) Length categories (inches) for size structure indices of largemouth bass, sunfish, and bullhead in Clove Lake
Brown Bullhead
Stock≥8 in≥3 in≥5 in
Quality≥12 in≥6 in≥8 in
Preferred≥15 in≥8 in≥11 in

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