Written by David Beasley, Director of Fisheries at SOLitude Lake Management
The Cohoke Fishing Club is a 47-member private sports club formed in 1900 in Central Virginia. The property is home to an 85-acre mill pond that was built in 1678. Throughout the club’s existence, quality Largemouth Bass catch rates have been inconsistent. In 2009 the fishery was at a low point; the bass were poor in quality, the catch rates were down and the pond was overrun with hydrilla. The club opted to work with a professional fisheries management company to achieve their goal of improving the bass population.
An initial assessment that included electrofishing and habitat surveys was conducted to identify limiting factors and formulate an effective fisheries management strategy. Following this step, meetings were held with club members to review the collected data, gather opinions, and design a comprehensive management plan based on goals and budget:
The first management step was to eradicate the invasive hydrilla present throughout the waterbody. Based on the budget and site conditions, the best long-term, budget-friendly control method available was to stock Triploid Grass Carp. This was done in the spring of 2010 in combination with a 10-acre herbicide treatment at the upper end of the pond to ensure anglers had access to the entire waterbody. With these combined approaches, the hydrilla was reduced by 100 percent within the first growing season.
Because members had elected to manage the fishery on a relatively low budget, it was important for the club to focus on improving the predator- to-prey ratio and fish habitat. Initial electrofishing results indicated that Gizzard Shad comprised the majority of the forage base. On the other hand, Bluegill and other sunfish were low in population due to decades of anglers harvesting all Bluegill and releasing all bass. This past approach played a role in the shad’s dominant position. To help rebuild the population while working with a small budget, 6,000 adult Bluegill were stocked and creel limits were altered to release all Bluegill while harvesting intermediate size Largemouth Bass.
Fish Cover and Nuisance Wildlife Removal
Club members added habitat strategically throughout open water to create cover for bass to ambush the shad. The fish cover installed also helped all species avoid predation from otters and cormorants during the cooler months, in particular, when water clarity improves and fish slow down due to cold water temperatures. In response to the large number of otters observed in the pond, an annual trapping program was implemented to reduce their population. Both of these strategies underscored the club’s goal of creating a self-sustaining, abundant forage base capable of supporting trophy bass.
Improving the fishery’s productivity was an important step in the process of boosting the forage fish population. In 2010, extensive water quality data was collected to better understand the limiting factors. The waterbody was then put on a fertilization program as well as a water quality monitoring program to help ensure success. In addition to fertilizing, multiple fish feeders were installed to boost Bluegill growth rates and rebuild their depleted population.
The final step in the process was education; if fishermen do not follow through with the management tasks required, then the fishery will not meet its potential. As is the case with many fishing clubs, the members had to overcome internal struggles in order to achieve the desired results. Members were instructed to no longer catch and release intermediate size bass. It is often very difficult to get anglers on board with doing the opposite of what their parents and grandparents had taught them, even when frustrated with the existing fishing conditions. The inherited resistance to harvesting bass was the primary hurdle preventing the pond from producing more consistent, high quality fishing.
2015 marked five years since the management strategy was set in motion. Over that time, the management tasks were carried out annually. Although all of the club members would not consistently conform to harvest recommendations, they did make strides in the right direction. Creel limits for Largemouth Bass were followed, but revised. Even though the club members failed to harvest the recommended number of bass within the first couple of years, over time they were able to get the member buy-in and make a significant impact. In the process of harvesting Largemouth Bass, efforts were also made to remove all other predators present in the pond, including black crappie, chain pickerel and white perch – and this proved to be a very effective strategy.
In line with the concern of some anglers, catch rates gradually decreased by around 20 percent over the years, but the quality of the bass increased significantly. The fishery transformed from anglers catching only one 15-inch bass for every five bass caught, to greater than 50 percent of the bass caught being greater than 15in. The 20 percent lower catch rate in exchange for a very positive shift in the quality and size of the fish has garnered enough support from the club’s members to start harvesting all bass less than 15in beginning in 2016.
The extensive historical fishing data from this pond illustrates that it has the potential to become great. In order for the club to continue with its success, it will need to stay focused on each of the following variables that impact bass growth: predator-to-prey ratios, water quality, plankton production, fish cover, otters, record keeping and harvesting.
David Beasley is the Director of Fisheries at SOLitude Lake Management, the nation’s leading environmental firm specializing is sustainable lake, stormwater pond, wetland and fisheries management solutions. To learn more about this topic, please visit www.solitudelakemanagement.com.