Pedaling Past the Bycatch Pitfall: Why Your Fishing Gear Might Be Catching the Ocean's Wrong Catch (and How to Shift Gears)

Every time a net is hauled or a line is set, there is a chance that something unintended comes along for the ride. That unintended catch—sea turtles, juvenile fish, seabirds, marine mammals—is what the industry calls bycatch. For many fishing operations, bycatch is more than an ecological concern; it represents lost time, damaged gear, regulatory fines, and a tarnished reputation. This guide is written for fishing crews, vessel owners, and fishery managers who want to understand why bycatch happens and how to reduce it without sacrificing target catch. We will walk through the mechanics of bycatch, compare proven reduction tools, and outline a step-by-step approach to shifting your gear setup. The goal is not to eliminate every unwanted organism—that is rarely possible—but to make your operation more selective and responsible.

Understanding the Bycatch Problem: Why Your Gear Catches More Than You Want

The root of bycatch lies in the mismatch between gear design and the behavior of non-target species. Most fishing gear is engineered to maximize catch of a target species—say, shrimp or tuna—but the ocean is a crowded place. A trawl net designed to scoop shrimp off the seafloor also scoops up whatever else is in its path: juvenile fish, crabs, and sometimes endangered sea turtles. Similarly, longlines baited for swordfish attract seabirds and sharks that dive for the bait before the hooks sink.

Bycatch is not random; it follows patterns based on depth, time of day, bait type, and gear configuration. For example, shrimp trawls in the Gulf of Mexico historically caught high numbers of sea turtles, leading to the development of Turtle Excluder Devices (TEDs). In Alaska, salmon fisheries have struggled with bycatch of halibut and crab, prompting the use of excluder grates and modified trawl designs. Understanding these patterns is the first step toward selecting the right reduction gear.

Many operators resist change because they fear losing target catch. This is a valid concern, but decades of field trials show that well-designed bycatch reduction gear can maintain or even improve target catch while dramatically reducing unwanted species. The key is to choose modifications that exploit behavioral differences between target and non-target species. For instance, fish tend to swim forward when encountering a net, while turtles and large debris tumble backward—a principle used in TEDs and fish excluders.

Common Bycatch Hotspots by Fishery

Different fisheries face different bycatch challenges. In bottom trawls, the main issues are sea turtles, sharks, and benthic invertebrates. In pelagic longlines, seabirds and sea turtles are primary concerns. Gillnets frequently entangle marine mammals and seabirds. Each scenario requires a tailored solution, not a one-size-fits-all device. Recognizing your specific bycatch composition is critical before investing in gear modifications.

Core Mechanisms: How Bycatch Reduction Gear Works

Bycatch reduction gear (BRG) operates on a few basic principles: physical exclusion, behavioral guidance, and escape. Physical exclusion uses rigid grids or mesh panels to block large animals from entering the codend. Behavioral guidance relies on light, sound, or water flow to steer non-target species toward an escape opening. Escape mechanisms include simple openings or chutes that allow animals to exit after entering the net.

The most common BRG is the Turtle Excluder Device (TED), which consists of a metal grid fitted inside the trawl neck. When turtles and other large objects hit the grid, they are guided upward and out through a flap, while shrimp and small fish pass through the bars. Similarly, fish excluder devices (FEDs) use a grid with wider bar spacing to allow juvenile fish to escape while retaining larger target species. In longline fisheries, circle hooks and bird-scaring lines reduce seabird bycatch by making bait less accessible during setting.

Each mechanism has trade-offs. Grids can clog with debris, requiring frequent cleaning. Escape openings can reduce target catch if not properly positioned. Behavioral devices like LED lights may attract or repel certain species unpredictably. The effectiveness of any BRG depends on correct installation, maintenance, and species-specific behavior. A device that works well for sea turtles may not help with sharks or seabirds.

Comparing BRG Approaches: Pros and Cons

Step-by-Step: Shifting Your Gear Setup

Transitioning to bycatch reduction gear does not happen overnight. It requires planning, testing, and adjustment. Below is a repeatable process that many operations have used successfully.

Step 1: Assess Your Bycatch Profile

Start by reviewing logbooks or observer data to identify which non-target species are most common in your catches. If data is limited, conduct a short monitoring period (e.g., 10–20 hauls) with a simple form recording species, size, and condition. Prioritize species that are endangered, regulated, or economically costly.

Step 2: Research Suitable BRG Options

Based on your bycatch profile, consult with gear specialists, extension agents, or fishery managers. Many regions have tested BRG designs specific to local fisheries. For example, the National Marine Fisheries Service (NMFS) in the U.S. provides approved TED designs for shrimp trawls. Look for designs that have been tested under conditions similar to yours.

Step 3: Procure and Install the Gear

Purchase BRG from reputable suppliers. Installation is critical—follow manufacturer instructions exactly. Common mistakes include incorrect grid angle, flap size, or mesh placement. If possible, have an experienced technician supervise the first installation.

Step 4: Conduct Comparative Trials

Run side-by-side tows with and without the BRG to measure changes in target catch and bycatch. Keep detailed records for at least 10 tows per condition. Calculate bycatch reduction percentage and target catch loss. If target catch loss exceeds 5–10%, consider adjusting the device or trying a different design.

Step 5: Iterate and Optimize

No BRG is perfect out of the box. Tweak bar spacing, escape opening size, or light color based on trial results. Document changes and share findings with other operators. Over time, you can develop a configuration that balances conservation and profitability.

Tools, Economics, and Maintenance Realities

Investing in BRG involves upfront costs, but the long-term savings can be significant. Reduced bycatch means less time sorting catch, lower bait loss, fewer regulatory penalties, and improved access to eco-label markets. However, the economics vary by fishery.

A TED for a shrimp trawl might cost $200–$500 per net, plus installation. Circle hooks are comparable in price to standard J-hooks but may require more frequent replacement. Bird-scaring lines are cheap (under $100 per set). The real cost is often in lost fishing time during trials and maintenance. A grid that clogs every few tows can reduce fishing efficiency by 10–20% if not cleaned regularly.

Maintenance is a hidden factor. BRG components are subject to wear, corrosion, and fouling. Inspect grids and escape openings before each trip. Replace worn flaps and corroded fasteners. Keep spare parts onboard. In some fisheries, regulators require BRG to be installed and functional at all times; failure to maintain can result in citations.

Economic Trade-offs at a Glance

For many small-scale operators, the initial cost is a barrier. Grants and cost-share programs are available through government agencies and NGOs. For example, the U.S. National Fish and Wildlife Foundation offers funding for bycatch reduction projects. Checking with local fisheries extension offices can uncover similar opportunities.

Growth Mechanics: Positioning Your Operation for the Future

Adopting BRG is not just about compliance; it is a strategic move that can strengthen your market position. Consumers and retailers increasingly demand sustainably sourced seafood. Eco-labels like Marine Stewardship Council (MSC) or Friend of the Sea require demonstrable bycatch reduction. By investing in BRG, you can differentiate your product and potentially command premium prices.

Furthermore, regulatory trends are moving toward stricter bycatch limits. Early adopters will have a competitive advantage when new rules take effect. For instance, the U.S. West Coast groundfish fishery implemented catch shares with hard bycatch caps; vessels that had already reduced bycatch could fish longer without hitting limits.

Networking with other operators who have successfully implemented BRG can accelerate your learning curve. Many fishing communities have gear workshops or online forums where practical tips are shared. Participating in collaborative research—such as testing new designs with scientists—can also provide early access to innovative solutions and build goodwill with regulators.

Persistence is key. Some operators try a BRG once, see a slight drop in catch, and abandon it. But most devices require a break-in period and fine-tuning. The operators who succeed are those who treat BRG as an ongoing improvement process, not a one-time fix.

Risks, Pitfalls, and How to Avoid Them

Even well-intentioned BRG implementations can fail. The most common mistake is choosing the wrong device for the fishery. A TED designed for large sea turtles may be ineffective for small fish excluders. Always match the device to your specific bycatch species.

Another pitfall is improper installation. A grid angled too steeply may not guide turtles upward; an escape flap that is too small may not allow animals to exit. Always follow manufacturer specs and, if possible, have an experienced installer check your setup.

Maintenance neglect is widespread. A clogged grid or torn flap renders the device useless. Set a schedule: inspect after every tow, clean grids daily, and replace worn parts weekly. Train crew members on proper maintenance procedures.

Finally, do not expect 100% bycatch elimination. Some bycatch is inevitable, especially in mixed-species fisheries. Set realistic goals—say, a 50–70% reduction in the most problematic species—and celebrate progress. Overpromising leads to disappointment and abandonment of the technology.

Mistakes to Avoid: Quick Checklist

• Using a device not tested in your fishery
• Skipping comparative trials before full deployment
• Neglecting crew training on installation and maintenance
• Ignoring clogging or damage during trips
• Giving up after one poor trial without adjusting

Frequently Asked Questions About Bycatch Reduction Gear

Below are common questions we hear from operators considering BRG.

Will BRG reduce my target catch?

It can, but usually by less than 5–10% if properly tuned. Many operators find that any loss is offset by reduced sorting time and fewer regulatory issues. Some designs actually improve target catch by reducing net clogging.

How long does it take to see results?

Most operators see measurable changes within the first 10–20 tows. However, fine-tuning may take several weeks. Be patient and keep records.

Is BRG mandatory in my fishery?

In many regions, yes. For example, U.S. shrimp trawls must use TEDs, and some longline fisheries require circle hooks. Check with your local fisheries management authority for specific requirements.

Can I build my own BRG?

While possible, it is risky. Homemade devices may not meet regulatory standards and could be less effective. If you build your own, test it thoroughly and compare with approved designs.

What if I fish in multiple areas with different bycatch?

Consider using modular BRG that can be adjusted or swapped between trips. Some operators carry multiple grid sizes or escape opening configurations.

Synthesis and Next Actions

Reducing bycatch is a journey, not a destination. The most successful operators start with a clear understanding of their bycatch profile, select gear that targets their biggest problems, and commit to iterative testing and maintenance. The benefits—lower costs, better market access, regulatory peace of mind, and a healthier ocean—are well worth the effort.

If you are new to BRG, begin with one device and one species. Run trials, document results, and adjust. Share your findings with peers. Over time, you can expand to address other bycatch issues. Remember, every net you modify is a step toward more sustainable fishing.

For further guidance, consult your local fisheries extension service or gear specialist. Many resources are available online, including design specifications and trial protocols. The ocean is a shared resource; by reducing bycatch, you are investing in its future—and yours.