How’s the Fishing? Tips for Managing Your Lake’s Fishery

The fishery of a lake is an intrinsic, incredibly dynamic element of a lake system, and managing a lake’s fishery can be a very complex endeavor. There is actually a lot more to it than simply stocking game fish. Although there is no “one way” in fisheries management, there are key guidelines that can be followed to maximize the recreational potential of your lake’s fishery and increase the success of your fishery management and stocking efforts. Over the past two decades, Princeton Hydro has been working with lake, pond, and reservoir managers to help them to align water quality, fishery, and ecological goals.

Princeton Hydro’s Founder, Dr. Steve Souza, recently gave a presentation on fisheries management at the Spring Meeting of the New Jersey Coalition of Lake Associations (NJCOLA). We’ve compiled a few essential elements from his presentation and have made the complete presentation available for free download.

Let’s dive in!

Benefits of a Healthy Fishery

Recreational fishing is an outdoor activity that can be enjoyed by people of all ages. When children are introduced to fishing, it helps cultivate a connection to the environment, thereby promoting outdoor activity and environmental stewardship among today’s youth.

Anglers have always served as important advocates for the conservation of natural resources. The sale of fishing licenses financially supports wildlife habitat conservation and enhancement as well as the protection and improvement of water quality. This increases the ecological services and functions of lakes and adds to their societal and recreational benefits.

A healthy fishery can have significant positive impacts on water quality. In a balanced, healthy fishery the ratio of forage and game fish affects the entire food web, helping to maintain the proper balance of zooplankton and phytoplankton. The “top down” ecological control associated with a balanced fishery minimizes algae blooms, sustains good water clarity and stable water quality. However, when the fishery is out of balance, the water quality and overall ecological health of the lake often suffers.

Before You Stock, Know Your Lake and Start with a Baseline

Before you do any fish stocking, it’s best to conduct a fishery survey. A fishery survey provides the vital data needed to design a stocking and management plan.

A balanced lake fishery is dependent on good water quality, ample habitat, and the correct ratio of predator and prey fish species. A properly designed and implemented fishery survey generates the data needed to quantify the overall composition of the existing fish community (predator vs. prey), the make-up of the forage (food) base, and the density and robustness of the lake’s top piscivores (prized game fish).

The resulting data helps identify if your fishery is balanced, which fish to stock, and how many of each species to introduce. It will also provide the benchmarks needed to solidify your management goals and, later on, help determine if the goals are being met. To stay on track, we recommend that a comprehensive fishery survey be conducted once every three years. Be sure to use the correct types and combination of “active” and “passive” sampling gear and thoroughly sample both the open water and nearshore areas of the lake.

The survey should include the collection and analysis of water quality data, and the mapping of available habitat. Water column water quality “profiles” provide vital information pertaining to the lake’s thermal and dissolved oxygen properties; key factors for a healthy, vibrant fishery. Here are some basic water quality guidelines:

  • Dissolved oxygen: ≥ 4 mg/L with 6-7 mg/L being ideal
  • For warm water fishery: Uniform temperatures at all depth (minimal or no thermal stratification)
  • For cold water fishery: Deep water temperature of 15 C, and dissolved oxygen ≥ 5 mg/L
  • pH: 6 to 8
  • Clarity: ≥ 3 feet (1 meter) Secchi disc transparency
  • Total Phosphorus: < 0.05 mg/L
  • Chlorophyll a: < 20 µg/L

Water quality sampling should also include an assessment of the lake’s zooplankton and phytoplankton communities, the base of your lake’s food web.

Floating Wetland Island

During the survey, take the time to quantify and map the distribution of existing forage, spawning, and refuge habitat. Lack of adequate habitat can significantly impede the fishery’s sustainability. This begins with the bathymetric mapping of the lake, which is basically an underwater survey of the bottom of the lake. This mapping shows where and how much shallow water versus open water habitat exists.  It can also help identify the location and distribution of important habitat types, such as shoals, rock piles, sandy open areas and natural structures (tree falls and snags). The data also helps determine where to create and introduce habitat, which can be in the form of brush piles, floating wetland islands, and other types of features that increase the spawning, recruitment, and foraging success of the fishery.

Stocking Your Lake

Once the fishery survey is completed, habitat is mapped and water quality analyzed, stocking can begin. In order to determine the specific stocking levels and rates that are right for your waterbody, here are some factors to consider:

  • Ensure your stocking efforts create or augment the correct ratio of predator (game) and prey (forage) fish.

  • Stock cautiously, focusing on a simple composition of predator and prey species. For most warm water lakes, largemouth bass should serve as the top predator and fathead minnow should be the primary prey.

  • Avoid problem fish, such as golden shiner, alewife and brown/black bullhead. Although these fish are often promoted as suitable forage species, they can be easily get overstocked and cause major disruptions of the fishery and to the degradation of water quality.

Go here for a more in-depth look at how to properly stock your fishery.

In Summary

A healthy sustainable fishery isn’t only a function of the types and amounts of fish stocked in a lake; it is directly a function of water quality, the availability and quality of spawning, foraging and refuge habitat, the ratio of forage to predator fish, and the overall composition and balance of the food web.

Begin with a fishery survey; the resulting data enables a correctly planned and implemented stocking program. Conduct routine surveys to assess the status of the fishery and the success of the program. Also, annual water quality testing provides the information needed to make wise pro-active fishery management decisions. It will also provide insights into the lake’s environmental conditions to ensure they are supportive of a healthy, productive and sustainable recreational fishery.

Learn More

If you’re interested in learning more about Princeton Hydro’s fisheries management or lake management services, please contact us.

Click here to download a full copy of Dr. Souza’s presentation, titled “How’s the Fishing? Maximizing the Recreational Potential of Your Lake’s Fishery,” which he recently presented at the NJCOLA Spring Meeting. The presentation provides an in-depth set of guidelines for fishery management, covering topics like data collection methods, habitat creation and enhancement, maximizing habitat quality, and details on various stocking species to consider for your lake.

NJCOLA unites lake communities throughout New Jersey through education and by formulating legislation favorable to the protection and enhancement of the State’s lake resources. NJCOLA meetings, held on a regular basis in the spring and fall, educate members on various topics and issues affecting lake communities ranging from legal to environmental.

The Spring NJCOLA meeting was well attended with over 60 participants representing lakes throughout New Jersey, including a number of lakes that are managed by Princeton Hydro – Lake Mohawk, Lake Hopatcong, White Meadow Lake, Lake Swanannona, Kehmah Lake, Culver Lake and Swartswood Lake.

To learn more about Princeton Hydro’s Pond and Lake services, including water quality sampling, bathymetric surveying, floating wetland islands, and fisheries, visit: http://bit.ly/pondlake 

 

Improving Water Quality & Reducing Habitat Loss with Floating Wetland Islands

Floating Wetland Islands (FWI), also known as floating treatment wetlands, are an effective alternative to large, watershed-based, natural wetlands. Often described as self-sustaining, FWIs provide numerous ecological benefits. They assimilate and remove excess nutrients that could fuel algae growth; provide habitat for fish and other aquatic organisms; help mitigate wave and wind erosion impacts; provide an aesthetic element; and can be part of a holistic lake/pond management strategy. FWIs are also highly adaptable and can be sized, configured and planted to fit the needs of nearly any lakepond or reservoir.

Princeton Hydro Senior Scientist Katie Walston recently completed the Floating Island International (FII) Floating Wetland Master Seminar. The seminar provided participants with an in-depth look at the various technologies and products FII offers. Through hands-on examples, course participants learned how to utilize wetland islands for fisheries enhancement, stormwater management, shoreline preservation, wastewater treatment and more.

“The Master Seminar was truly valuable both personally and professionally,” said Katie. “I learned a tremendous amount and thoroughly enjoyed the experience. It’s very fulfilling knowing that I can take the knowledge I’ve learned back to Princeton Hydro and make positive impacts for our clients.”

FII was launched by inventor and outdoorsman Bruce Kania who was driven by the desire to reverse the decline of wetland habitats by developing a new and natural stewardship tool that could clean water and, in the process, improve life for all living creatures. He found that the answer lies in Biomimicry: duplicating nature’s processes in a sustainable, efficient and powerful way to achieve impeccable environmental stewardship for the benefit of all life.

Bruce brought together a team of engineers and plant specialists and created BioHaven® floating islands. These islands biomimic natural floating islands to create a “concentrated” wetland effect. Independent laboratory tests show removal rates far in excess of previously published data: 20 times more nitrate, 10 times more phosphate and 11 times more ammonia, using unplanted islands. They are also extremely effective at reducing total suspended solids and dissolved organic carbon in waterways.

Due to population growth, industrialization and climate change, wetlands are at risk of rapidly declining in quantity and quality due. However, every floating wetland island launched by FII provides an effective strategy for mitigating and adapting to the impacts of over development and climate change.

The unique design of BioHaven® floating islands means that 250 square feet of island translates to an acre’s worth of wetland surface area. These versatile floating islands can be launched in either shallow or deep water, and can be securely anchored or tethered to ensure that they remain in a specific location. They are almost infinitely customizable, and can be configured in a variety of ways.

In addition to ongoing prototype development, FII offers licensing opportunities to businesses and production facilities worldwide. FII continues to research and develop collaborative pilot projects to quantify BioHaven® floating islands’ efficacy.

Many thanks to Bruce and Anne Kania for hosting the Floating Wetland Master Seminar and inspiring action through their knowledge, passion and ongoing endeavors.

 

Pesticide-Free Lake Management Solutions

Blue Water Solutions for Green Water Problems

Managing your lakes and ponds without the use of pesticides

 

Proper lake and pond restoration is contingent with having a well prepared management plan. If you don’t start there, you’re just guessing as to which solutions will solve your problem. Successful, sustainable lake and pond management requires identifying and correcting the cause of eutrophication as opposed to simply reacting to the symptoms (algae and weed growth) of eutrophication. As such, Princeton Hydro collects and analyzes data to identify the problem causers and uses these scientific findings to develop a customized management plan for your specific lake or pond. A successful management plan should include a combination of biological, mechanical and source control solutions.  Here are some examples:


Biological Control:

Floating Wetland Islands (FWIs) are a great example of an effective biological control solution. They have the potential to provide multiple ecological benefits. Highly adaptable, FWIs can be sized, configured and planted to fit the needs of nearly any lake, pond or reservoir.

BROOKS LAKE FWI

Often described as self-sustaining, Floating Wetland Islands:

  • Help assimilate and remove excess nutrients that could fuel algae growth
  • Provide habitat for fish and other aquatic organisms
  • Help mitigate wave and wind erosion impacts
  • Provide an aesthetic element
  • Can be part of a holistic lake/pond management strategy

Read an article on Floating Wetland Islands written by our Aquatics Director Fred Lubnow.

Mechanical Control:

Another way to combat algae and invasive weed growth is via mechanical removal. One of the mechanical controls Princeton Hydro employs is the TruxorDM5000, an eco-friendly, multi-purpose amphibious machine that provides an effective, non-pesticide approach to controlling invasive weeds and problematic algae growth.

The TruxorDM5000: TRUXOR

  • Is capable of operating in shallow ponds and lakes where the access and/or operation of conventional harvesting or hydroraking equipment is limited
  • Is highly portable and maneuverable, yet very powerful
  • Can cut and harvest weeds and collect mat algae in near-shore areas with water depths less than three feet
  • Includes various attachments that allow the machine to easily collect and remove a variety of debris
  • Can be outfitted for sediment removal/dredging

Check out the Truxor in action here! 

Source Control:

Because phosphorus is typically the nutrient that fuels algae and weed growth, excessive phosphorus loading leads to problematic algal blooms and can stimulate excessive weed growth. One of the most sustainable means of controlling nuisance weed and algae proliferation is to control phosphorus inputs or reduce the availability of phosphorus for biological uptake and assimilation. The measures that decrease the amount or availability of phosphorus in a lake or pond are defined as “source control” strategies.

Deerfield Lake, PA – PhosLockTM treatment Through data collection and analysis, we can properly identify the primary sources of phosphorus loading to a lake and pond, whether those sources are internal or external.  Our team of lake managers, aquatic ecologists and water resource engineers use those data to develop a management plan that quantifies, prioritizes and correctly addresses problem sources of phosphorus.

PhosLockTM and alum are often utilized as environmentally-safe and controlled means to limit phosphorus availably. Although PhosLockTM works similar to alum, it does not have some of the inherent secondary environmental limitations associated with alum. PhosLockTM is a patented product that has a high affinity to bind to and permanently remove from the water column both soluble reactive and particulate forms of phosphorus. This makes it a very effective pond and lake management tool.

Read more about controlling harmful algae blooms.

These are just a few of the examples of non-pesticide lake and pond management strategies that Princeton Hydro regularly utilizes. Properly managing your lakes and ponds starts with developing the right plan and involves a holistic approach to ensure continued success. For more ideas or for help putting together a customized, comprehensive management plan, please contact us!