MLMA Master Plan Appendix M. Bycatch Mitigation Measures and Considerations

This appendix provides an overview of considerations associated with a range of bycatch mitigation and discard mortality measures. As with the other appendices, it is anticipated this overview will continue to be expanded and refined as part of Master Plan implementation so it can serve as an effective resource to managers and stakeholders.


As discussed in Chapter 6, bycatch can increase the time, cost, and effort required to catch a desired amount of target species and can have adverse consequences for vulnerable stocks and ecosystems. As a result, fishermen, scientists, engineers, and resource managers have developed a wide array of strategies to reduce bycatch.

The MLMA requires that bycatch be limited to acceptable types and amounts. Where unacceptable bycatch occurs in a fishery, management measures that minimize bycatch and discard mortality should be implemented. This appendix provides a non-exclusive list of common bycatch mitigation measures that have been demonstrated to minimize bycatch and discard mortality when appropriately designed and implemented. It also provides associated considerations and existing California or West Coast examples of implementation where available.

Identifying appropriate methods for addressing bycatch concerns requires an intimate understanding of the fishery in question. This includes knowledge of the fishing gear and operational practices, distribution and behavior of bycatch species, spatial and temporal characteristics of fishing activity, and other variables. In most cases, some combination of bycatch mitigation measures may be necessary to effectively address unacceptable bycatch. For example, gear modifications are often paired with incentive programs for fishermen and supplemented by a time/area closure that prevents fishing when sensitive bycatch species are most likely to be present.

Electronic monitoring is one method for collecting bycatch data. Here a monitoring system’s cameras (top center) are attached to the vessel’s stabilizers. (NOAA photo)
The cameras record fishing activities on the vessel, and software can help identify and measure different fish species in the images. (NOAA photo)

Evaluating and monitoring bycatch

Information on the type and quantity of bycatch in an individual fishery is necessary to select appropriate bycatch mitigation measures. This information is not always available with sufficient certainty to identify mitigation strategies. In such cases, increased data collection may be the most appropriate short-term strategy. Data collection efforts using dockside monitoring, logbooks, observers, or fisheries-independent or -dependent studies can establish the information necessary to make informed decisions about bycatch mitigation strategies. Each of these data collection methods has its own set of considerations. For example, logbooks can be used to collect information at minimal cost to the Department, but fishermen may not have the knowledge or incentives to report completely and accurately. Dockside monitoring surveys or landing receipts can only collect data on retained species and thus will provide no information on discards. Observers are likely the most reliable and comprehensive data collection method, but costs can be prohibitive and observers may influence normal fishing activities.

No single data collection technique can effectively establish estimates of bycatch in the diverse range of state-managed fisheries. Different fishery-specific characteristics and factors must be considered when determining the appropriate methods of data collection and reporting. Standardized reporting methodologies can help ensure that effective bycatch data collection programs are developed for each fishery. See Appendix H for more details on data collection strategies.

A CDFW biologist sampling sublegal halibut bycatch aboard a California halibut trawl vessel. (CDFW photo by Kristine Lesynak)
Lingcod bycatch in an experimental box crab trap. (CDFW photo by Lindsay Orsini)

Categories of bycatch mitigation measures and associated considerations

The International Guidelines on Bycatch Management and Reduction of Discards, prepared by the Food and Agriculture Organization of the United Nations (FAO) and endorsed by the United Nation’s Committee on Fisheries, states that best practices for bycatch mitigation measures include ensuring that all measures are: “(i) binding; (ii) clear and direct; (iii) measurable; (iv) science-based; (v) ecosystem-based; (vi) ecologically efficient; (vii) practical and safe; (viii) socioeconomically efficient; (ix) enforceable; (x) collaboratively developed with industry and stakeholders; and (xi) fully implemented” (FAO 2011). In some circumstances, however, voluntary or experimental measures may be the most appropriate.

The bycatch mitigation measures outlined below fall under seven main categories, each with general considerations regarding implementation:

  1. Gear modifications: Modifying gear design, materials, and configuration has proven effective as a bycatch mitigation measure in many fisheries. Effective modifications are fishery-specific, depending on the type of gear used and the portfolio of bycatch species. As a result, fishery-specific studies may be necessary to establish the efficacy of particular gear configurations to mitigate bycatch. Gear modifications result in up-front and possible ongoing maintenance costs for fishermen, which can be defrayed by financial incentives. Dockside gear checks or patrols can ensure that fishing vessels are taking steps to comply with gear modification requirements, but on-board monitoring (human or electronic) is necessary to ensure full compliance.
  2. Bycatch catch limits: Placing limits on the number of individuals or weight of bycatch in a fishery is perhaps the most straightforward way to reduce bycatch. Catch limits can include zero quotas and required release, quotas that would require full retention and reporting of bycatch, or hard caps that would close a fishery once exceeded. Depending on the design of a bycatch quota program, monitoring may be a substantial cost that’s borne by participants, the Department, or both. Landing receipts or logbooks may provide some assurance of compliance, but on-board monitoring (human or electronic) is the only way to ensure full compliance. Catch limits may result in lost fishing opportunities if hard caps are imposed. To ensure that catch limits or hard caps are protective of the species without unjustifiably damaging economic opportunities, data on the abundance, productivity, and mortality of the bycatch species is required.
  3. Spatial and temporal measures: Spatial and temporal measures restrict fishing or use of certain gear types at a time of year and/or in a geographic location when bycatch is expected. Other measures that fall under this category may dictate the manner and timing of gear deployment, such as night setting or depth restrictions. Establishing spatial and temporal measures will require sufficient scientific information to demonstrate their efficacy. Enforcement can be accomplished by patrols, VMS, or on-board observers. These measures may result in lost fishing opportunities and may have direct costs to fishermen depending on how monitoring costs are assigned.
  4. Incentive/disincentive programs: Programs that provide incentives or disincentives related to bycatch can encourage fishermen to innovate their practices to avoid bycatch. Certain incentive programs can ease the burden of regulatory requirements on fishermen. For example, rebates, tax breaks, or other discounts/subsidies can facilitate the transition of a fishery to more selective gear. Likewise, establishing a system of performance standards (e.g., rewards and/or penalties based on bycatch rates) can spur innovation and encourage good practices. These programs will have some administrative costs but can ultimately be revenue-neutral or -positive if penalties are designed to equalize or exceed rewards. Purchasing incentive programs will have minimal enforcement needs, while performance standards may require significant monitoring to guarantee fairness.
  5. Strategies to minimize “ghost fishing”: The ongoing effects of abandoned or lost fishing gear can be mitigated by these strategies, including gear recovery programs and design standards. These programs will have some administrative costs, particularly gear recovery programs that require vessel trips to recover gear. These costs can be defrayed by mandatory or voluntary buyback of recovered gear that is marked with ownership identification. Gear design using degradable materials may have some up-front and ongoing costs to fishermen.
  6. Full retention programs: Full retention reduces discard mortality to zero. These programs may not improve bycatch outcomes on their own, but they can reduce waste, enable comprehensive monitoring of bycatch, and may incentivize fishermen to innovate gear or fishing practices to avoid low-value bycatch. Full retention programs may reduce overall profit from fishing due to low-value catch. These programs have minimal direct cost to the Department but may result in increased analysis and reporting needs if paired with requirements to report the type and amount of bycatch in the fishery.
  7. Other: Several other strategies have demonstrated success in reducing bycatch or discard mortality. These include descending devices, use of predictive mapping applications to avoid bycatch hotspots, education and training programs, and improved monitoring and enforcement. Burdens on the Department and fishermen vary depending on the strategy.

In addition to the bycatch mitigation strategies outlined above, many management measures focused on target species have incidental benefits for bycatch. For example, where a target stock is overfished, a reduction in overall effort may be necessary. Such effort reductions will often also reduce total mortality of bycatch species. See Appendix K for more information.

Table M1 below provides a range of common bycatch mitigation strategies and identifies considerations and examples associated with each. Considerations include evidence for the efficacy of the mitigation measure under different circumstances, the potential economic effect on fishing communities, and implementation and enforcement needs.

Table M1. Common bycatch mitigation strategies, and associated considerations and examples.
Efficacy in mitigating bycatch Economic effects on fishermen Enforcement requirements
Gear modifications Acoustic devices (e.g., pingers) Alert animals to presence of fishing gear. Effective for sound-sensitive species (e.g., marine mammals). Several trials of pingers on fishing nets resulted in 70-90% reduction in cetacean bycatch (Cox et al. 2007). Pingers recommended by the International Whaling Commission in 2001 (IWC 2001). Cost of individual pingers is low. Longer nets will require more pingers at increased cost. These costs may be offset by reductions in net damage or loss from interactions with marine mammals (NMFS 1997). Dockside gear checks or patrols can ensure presence of pingers. As part of the Pacific Offshore Cetacean Take Reduction Plan, all drift gillnets must have acoustic deterrent devices (50 Code of Federal Regulations §229.31(c)). Studies show a 75% reduction in cetacean entanglement (NMFS 1997).
Visual devices (e.g., Light Emitting Devices, bait dyes, colored gear) Alert animals to presence of fishing gear. Effective for light/color-sensitive species. The use of LED lights along the fishing line dramatically reduces bycatch of threatened and depressed fishes in Pink Shrimp trawl nets with no effect on target catch (Hannah et al. 2015). Cost of bait dye and lights of LED systems is relatively low. Dockside gear checks or patrols can ensure use. LED lights are suggested for Pink Shrimp trawl nets to reduce bycatch of Eulachon Smelt and other sensitive species, although no regulations are currently in place. Studies show a 70-90% reduction in bycatch (Hannah et al. 2015).
Mesh size optimization Alterations to mesh size in nets. The use of larger mesh sizes results in a reduction of smaller and sub-legal sized bycatch (Alverson et al. 1994). Changes to mesh size requirement may require production or purchase of all new netting, or alterations to existing netting. Cost and time required will vary. Dockside gear checks or patrols can ensure appropriate mesh sizes. Trawl vessels targeting California Halibut in California Halibut Trawl Grounds must use a minimum cod end mesh size of 7.5 inches (§ 8496(g–h)). Studies show a reduction in bycatch of sub-legal halibut (Schott 1975).
Bycatch Reduction Devices (BRDs) in trawl nets A hard grid, large-hole mesh, and/or escape hatch designed to allow escape or exclude catch of turtles, debris, large animals, free swimming fish in trawl nets. BRDs are recognized as effective in reducing bycatch. The efficacy of specific BRDs depends on their design, the fishery in which they are used, and the profile of bycatch species (Eayrs 2007; Alverson et al. 1994). Cost of BRDs varies considerably. Small mesh windows may cost a few dollars, while large steel grates may cost up to $1,000 (Eayrs 2007). Dockside gear checks or patrols can ensure presence of BRDs. Pink Shrimp trawl nets must have BRDs to reduce bycatch of groundfish (e.g., Pacific Hake, Sablefish, Yellowtail Rockfish; §8841; California Code of Regulations Title 14 §120.1(c)). Studies show a 66-88% reduction of bycatch (Hannah and Jones 2007).
Escape ports in traps Allow bycatch species to escape traps. Escape ports reduce sub-legal sized individuals in traps (Stewart 1974). The use of escape ports in pots and traps is common practice. Any increases in the minimum port size would require alterations to existing traps. minimum port size would require alterations to existing traps. Dockside gear checks or patrols can ensure presence of escape ports. Lobster and crab traps must have escape openings of varying number and size (§ 9010–9011).
Streamers A line runs from a high point of a vessel to a drag buoy towed behind. Streamers are attached to the line and scare birds away from surface lines, bait, and hooks. Streamers reduce seabird interactions with longline gear (Melvin et al. 2004). This measure does not require significant changes to the fishing gear or vessel and has minimal costs (Sato et al. 2012). Dockside gear checks or patrols can ensure presence of streamer lines. Groundfish longline vessels in Alaska state and federal waters must have streamers (50 Code of Federal Regulations §679.24(e)(3–4); Alaska Administrative Code Title 5 §28.055). Streamers are most necessary for use with pelagic longlines, which are not currently used in California.
Hook selection Some hooks types, such as circle hooks, may result in reduction in bycatch and/or increase in post-release survival of bycatch. Circle hooks can reduce rates of bycatch and post-release mortality in longline fisheries or hook-and-release fishing (NMFS 2008; PFMC 2000). Hook size also influences bycatch mitigation. Transitioning hook type or size will have relatively low cost to fishermen. May impact catch rates of target species. Dockside gear checks or patrols can ensure presence of appropriate hook type and size. Use of circle hooks required for some salmon fishing (California Code of Regulations Title 14 §27.80(a) and §182(c).
Bait selection Use of different baits can increase selectivity. The use of fish instead of squid as bait reduces bycatch of turtles and sharks in longline fisheries (NMFS 2008). Transitioning bait type will usually have minimal cost to fishermen but may impact fishing efficacy. Dockside gear checks or patrols can ensure presence of appropriate bait. No existing regulatory examples in California.
Marine mammal entanglement gear modifications Several modifications to the material or configuration of gear have been proposed to reduce marine mammal entanglements in lines (CDFW and OPC 2017; PSMFC 2017). Suggested gear modifications include reducing length of vertical and trailer lines to minimize slack and changing rope color and material. Preliminary evidence suggests reducing slack and accessory lines may have the greatest positive effect (CDFW and OPC 2017). Adjusting length of lines may take some time when changing set location across depths. Breakaway lines may have more materials cost and potential for lost gear. Straightforward gear modifications are likely less costly than a Take Reduction Team (PSMFC 2017). Dockside gear checks or patrols can ensure appropriate gear configuration. Updated best practices guide for crab fishing strongly recommends reducing slack in vertical lines and the number of accessory lines and trailer buoys (CDFW and OPC 2017). Measures are not mandatory at this time.
Bycatch catch limits Quotas/catch limits/hard caps /triggers Reduce absolute numbers of bycatch. May have no/minimal effect on post-release mortality. Can be vessel- or fishery- specific and transferable or nontransferable. Catch limits reduce landings of bycatch. Defensible quotas or hard caps should be based on the abundance, productivity, mortality, and ecosystem role of species and subject to effective monitoring. Quotas can function as incentive to change fishing gear or practices to avoid bycatch (Alverson et al. 1994). Quotas can exacerbate discard mortality and derby fishing unless paired with comprehensive tracking of catch and consequences for quota exceedance (Marine Fish Conservation Network 2004). Costs to fishermen may include monitoring costs and any lost fishing opportunities (O’Keefe et al. 2012; Patrick and Benaka 2013). For example, hard cap limits lead to fishery closures when exceeded. Requires significant monitoring and reporting to achieve compliance. High monitoring needs. Hard caps typically require 100% monitoring (NMFS 1997). Bycatch of sturgeon, halibut, salmon, Steelhead and Striped Bass may not be taken by or possessed on any herring fishing vessel (California Code of Regulations Title 14 §163(e)).

Federal groundfish management on the west coast allows for and utilizes sector- and vessel-specific total catch limits for some bycatch species and prohibits retention of others (50 Code of Federal Regulations §660.55(m)). These bycatch limits have led to early season closures several times (e.g., 73 Federal Register §53,763.

Proposed hard caps for marine mammal and sea turtle interactions in California drift gillnet fishery were withdrawn in 2017 due to potential economic impacts (82 Federal Register §26,902).
Spatial and temporal measures Closures with temporal (time) and/or spatial (area) dimensions Restrict fishing or use of certain gear types at a time of year and/or in a geographic location when bycatch is expected. Time/area closures can reduce bycatch when target and bycatch species segregate spatially or temporally (Alverson et al. 1994). The occurrence of bycatch species can be gleaned from behaviors and physiological traits of the species (Dunn et al. 2011). Depending on the size and complexity of time/area closures, they could be either an inconvenience for or adversely affect fishermen (Erickson and Berkeley 2008). Closed areas must be monitored and enforced. Patrols or VMS (see below) are likely necessary to ensure compliance. Depth and season restrictions apply in Cowcod Conservation Areas to protect several rockfish species (California Code of Regulations Title 14 §27.50).

Certain areas of the California Habitat Trawl Grounds are closed to fishing to protect bycatch, as well as habitat and ecosystems. These closures have spatial but no temporal dimension (§8495(c)). CDFW data show a range of bycatch and discard percentages for each of the closed areas that are now avoided (CDFG 2008).

Spatial restrictions can also be voluntary. The California Groundfish Collective and The Nature Conservancy work together to develop fishing plans to manage bycatch risk in the Pacific groundfish fishery (see:
Dynamic ocean management Adaptive closures or avoidance schemes based on real-time information sharing between government, scientists, and fishermen. May be mandatory or voluntary. Implementation of dynamic ocean management can both reduce overall restrictions on fishing communities and mitigate bycatch concerns (Dunn et al. 2016). Complexity of the program and possible information reporting may present some cost or inconvenience to fishermen. Possible benefits by replacing large static closures with smaller dynamic closures. Closed areas must be monitored and enforced. Patrols or VMS (see below) are likely necessary to ensure compliance with mandatory closures. Proposed use of the “EcoCast” model to avoid areas of predicted bycatch in California drift gillnet fishery Exempted Fishing Permit (NMFS 2016).

University of Massachusetts Dartmouth School for Marine Science & Technology Bycatch Avoidance Program collects the geographic location of yellowtail bycatch from scallop fishermen in New England. Each day, the data are compiled in an email notice describing spatial areas to avoid based on bycatch of yellowtail from the previous day (O’Keefe and DeCelles 2013).

Use of Sea State in the Pacific Whiting fishery cooperative to avoid bycatch.
Altering the time or depth of gear setting Can influence bycatch by avoiding parts of water column or times of day in which bycatch is most active. The time or depth of setting can reduce certain types of bycatch in certain fisheries. For example, setting drift gillnets lower in the water column reduces cetacean and sea turtle bycatch (NMFS 1997). Likewise, night setting can reduce seabird bycatch in longline fisheries (Petersen 2008). Minimal direct cost. Possible lost opportunity costs, but study on depth setting requirements for the California drift gillnet fishery show minimal effect on target catch rates. Potential loss of catch may be offset by reductions in net damage or loss (NMFS 1997). Human or EM and/or patrols required to effectively enforce. As part of the Pacific Offshore Cetacean Take Reduction Plan, all drift gillnets must have extenders, which ensure nets are a minimum of 36 feet below the surface of the water (50 Code of Federal Regulations §229.31(b)). Studies show a 25% reduction in marine mammal bycatch (NMFS 1997).
Limit soak time Reducing the amount of time gear is in the water can reduce bycatch and improve survival of discards. Mortality of catch increases with increased soak time in pelagic longlines (Erickson and Berkeley 2008). Appropriate soak time will vary by fishery. Minimal direct cost. Possible lost opportunity cost, but studies show that limiting soak time has no effect on target catch of some species (Erickson and Berkeley 2008). Human or EM and/or patrols required to effectively enforce. All traps have maximum soak times of 96 hours (§9003).
Incentive/ disincentive programs Performance standards penalize fishermen based on conformity with pre-determined bycatch or bycatch mortality performance standards. Reward (e.g., increase quota, longer season, monetary reward) orand innovations in fishing practice (PFMC 2007). Rewards and/or penalties can incentivize compliance This program could provide rewards for voluntary reductions in bycatch. May provide for penalties as well. May require 100% monitoring. NA
Permit attrition programs or buybacks Buying out capacity of certain permit types or allowing transition to other permit types. Selectively-targeted buybacks can facilitate transition to more selective gear or reduce overcapacity (Squires et al. 2007). Possible costs to outgoing fishermen, depending on administration of the program. May result in increased revenues if overcapacity is addressed (Squires et al. 2007). Dockside gear checks and/or patrols needed to ensure phased-out gear types are not in use. A buyback was conducted in the Pacific groundfish fishery in 2005, however, the motivation was primarily related to target stock sustainability.
Gear recovery programs Government program or incentive for fishermen. Focused on recovering lost gear. Gear recovery programs are an established method to reduce ghost fishing (Macfadyen et al. 2009). No cost to fishermen, unless recovery costs must be reimbursed by identified gear owners. Possible compensation for fishermen that participate in recovery. No enforcement needs. California Lost Fishing Gear Recovery Project has removed more than 60 tons of fishing gear from California waters since 2006 (Seadoc 2009). Also see Senate Bill 1287 (McGuire).
Strategies to avoid/reduce ghost fishing by lost or derelict gear. Lost gear is known to continue catching target and non-target species (Macfadyen et al. 2009). Use of degradable materials or destruct devices in gear design Use of materials in gear design that will destruct over time and allow trapped catch to escape. Use of biodegradable materials in nets and pots reduces ghost fishing (Macfadyen et al. 2009). Use of biodegradable gear is likely to have upfront and ongoing maintenance costs for fishermen. Dockside gear checks or patrols can ensure appropriate gear configuration. Full observer coverage necessary to ensure 100% proper use. All traps must have one destruction device (§ 9003). Approved destruction devices are outlined in regulation (California Code of Regulations Title 14 §180.2).
Ownership identification on gear Establishes accountability and places more responsibility on the owner to track and recover their lost gear. Required marking of gear facilitates gear recovery programs and encourages responsible fishing (Macfadyen et al. 2009). Minimal costs to fishermen. Fishermen incentivized to do this already to indicate gear ownership. Enforcement efforts not likely necessary, as this is common practice with non-regulatory incentives. All traps must be marked with a buoy that identifies the operator (§9006).

Herring gillnets must be marked with a buoy that identifies the vessel number (California Code of Regulations Title 14 §163(f)(2)(F)).
Require full retention of all or a portion of a vessel’s catch Reduce discards and increase utilization of species that would otherwise be dead discards. Useful when retained catch cannot be released alive. Must consider the status and productivity of bycatch species. Thisdoes not necessarily minimize mortality. Full retention programs can be effective when tailored to avoid increases in total mortality of overfished species. Retention programs enable more comprehensive enumeration of bycatch and encourage fishermen to alter their activities so they are less likely to encounter non-target species (PFMC 2007). Possible costs to fishermen if required to land species with lower economic values (PFMC 2007). Must be accompanied by an appropriate monitoring and enforcement strategy. Full monitoring coverage only way to ensure 100% compliance. Participants in EM Exempted Fishing Permits in the Pacific groundfish fishery are required to operate under full retention rules with limited exceptions for some species (see:
Full retention programs Restrictions on offal discharge Require offal discharge away from lines to distract seabirds, or prohibit discharge. Discharging offal on the opposite side of the vessel from gear deployment minimizes seabird bycatch (Cox et al. 2007). Minimal costs to fishermen. Full monitoring coverage only way to ensure 100% compliance. Groundfish longline vessels in Alaska state and federal waters must discharge offal in a manner that distracts seabirds from baiter hooks (50 Code of Federal Regulations §679.24(e)(2)(v); Alaska Administrative Code Title 5 §28.055).
Other bycatch mitigation, accountability, and data collection strategies Training Share fishing methods or proper handling and release techniques to minimize bycatch and maximize post-release survival. Education and training programs are a recognized method to mitigate bycatch concerns (PFMC 2007). Government funded trainings may have some attendance cost to fishermen. Costs can be defrayed by travel reimbursements or stipends. Minimal enforcement costs. Administration of training program will have monetary costs that depend on the length and complexity of trainings. As part of the Pacific Offshore Cetacean Take Reduction Plan, all drift gillnet vessel operators must attend skipper education workshops after notification from NMFS (50 Code of Federal Regulations § 229.31(d)). This program is expected to facilitate successful implementation of the take reduction plan and accompanying regulations (NMFS 1997).
Descending and de-hooking devices Increase post-release survival of bycatch Appropriate use reduces post-release mortality (Hannah and Matteson 2007). Cost of devices vary from homemade to commercial devices (CDFW 2014). Dockside monitoring to ensure all vessels are equipped. The Department currently encourages the use of a variety of descending devices for rockfish (CDFW 2014). When descending devices are utilized, survival rates increase.
Observers and Electronic Monitoring Observers and EM can collect data on bycatch and fishing operations. Observers can function as a spotter for protected species and/or report violations. Observer and EM programs can ensure compliance with many regulations and support management decisions through data collection. Possibility of inaccurate data due to the presence of observers or EM influencing fishing behavior (Alverson et al. 1994; NMFS 2013). Observers may be most useful for emerging or experimental fisheries with no data on their effect (Commission 2005) Costs to fishermen will depend on the cost-sharing arrangement between government and fishermen for observers (NMFS 2013). Observers can have significant logistical costs to fishermen. In some fisheries, observers report violations themselves, while in others law enforcement officers can use the data. Observer programs are some of the most expensive and funding is a primary concern (Department of Commerce 2003; NMFS 2013). EM can reduce these costs, but typically collect more limited information focused on accountability. Tanner Crab permittees must have observers on board who collect a variety of information including bycatch, incidental take, and discards (California Code of Regulations Title 14 §126(a)(8)). This observer program was vital for understanding the effects of this relatively new fishery and establishing its management approach (Commission 2005).
Vessel monitoring systems VMS allows monitoring of the location of vessels. VMS is a more cost-effective method to ensure compliance with area closures (Department of Commerce 2003). Equipment and communication costs are estimated at $3,250–$6,750 up front and $1,750 annually per boat. Costs to fishermen will depend on the cost-sharing arrangement between government and fishermen (Department of Commerce 2003). Monitoring personnel required. High potential costs of implementation, but the VMS program costs are significantly less than traditional surveillance methods using ships and aircraft (Department of Commerce 2003). Certain vessels in the west coast groundfish fishery must carry and operate a VMS unit when at sea (50 Code of Federal Regulations §660.14). VMS data is communicated to NOAA’s office of law enforcement for use in focusing patrol efforts, preventing violations, and as evidence in prosecutions (see:
Avoiding protected species through operational techniques Using spotters or fleet communications to avoid bycatch hotspots; establishing procedures (e.g., back-down procedure for purse seines) to release protected species caught in gear. Changes in operational techniques and patterns can effectively avoid bycatch of large or easily identifiable protected species. Possible lost opportunity costs if large bycatch species impede fishing efforts. Patrols or observers may be necessary to ensure compliance with required procedures. Use of Sea State and operational and communication protocols in the Pacific Whiting Conservation Cooperative designed to avoid bycatch (see:


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Photo at top of page: Spiny lobster and round stingrays in a spiny lobster trap. (CDFW photo)