Technical Note On Developing A National Plan Of Action For Assessing And Reducing The Incidental Catch Of Cetaceans In Fisheries
This is not an exclusive or complete list but provides guidance for preparation of a national plan of action for reducing cetacean by-catch. This is a plan that a State designs, implements and monitors to assess and reduce the incidental catch of cetaceans in its fisheries.

The national plan of action should contain the following elements:

1. Formal plan of assessment
The purpose of the assessment is to determine the extent and nature of a State’s incidental catch of cetaceans in fisheries. The assessment should include, but is not limited to, the collection and analysis of data describing:

• Fishing fleets, including size of fleet (number of vessels), fishing methods, fishing areas and measures of fishing effort.

• Status of cetacean populations in the fishing areas, including estimates of abundance, population structure, trends and potential rates of increase, where known.

• Estimates of by-catch rate of cetaceans (e.g. per haul or per trip), derived from independent observer programs where possible.

• Estimates of the total annual incidental catch of cetaceans, combining measures of by-catch rate with appropriate estimates of fishing effort.

• Estimates of the sustainable level of incidental mortality for each cetacean population or stock, using empirical data or proxies from comparable species or populations.

• Existing mitigation measures in use and their effectiveness in reducing incidental catches.

• Statement of the decision logic used to develop and implement a national plan of action for reducing cetacean bycatch.

3. Research and development
The national plan of action should contain plans for research and development, including those aiming to develop the most practical and effective mitigation measures and to evaluate the effectiveness of various mitigation measures in use or being planned.

4. Monitoring and evaluation
The national plan of action should also include specific plans to monitor fisheries and cetacean populations after mitigation measures are implemented. These monitoring programs should allow determination of whether or not mitigation measures are achieving desired reductions in incidental mortality of cetaceans over a specific time frame. Reasonable milestones should be set to measure progress, and to trigger revisions when needed.

5. Education, training and outreach
The national plan of action should: prescribe means to raise awareness among fishers, fishing associations and other relevant groups about the need to reduce the incidental catch of cetaceans in fisheries; promote the implementation of the national plan of action among industry, the scientific community, government and the public; and provide information about technical or financial assistance for reducing the incidental catch of cetaceans.

Technical Note on Measures For Reducing The Incidental Catch Of Cetaceans In Fisheries
The most appropriate mitigation measures for each situation will depend on the nature and scope of the fishery, the species and behavior of the cetaceans involved and the financial resources available to address the problem. It is important to note that, unlike the situation with by-catches of many other taxa, the mechanisms responsible for incidental catches of cetaceans are poorly understood. It is unclear, for example, why dolphins and porpoises, equipped with a sophisticated echolocation system, do not detect and avoid fishing gear in which they become entangled.

For each of the general measures described below, the effectiveness and the cost involved for fishers are briefly presented. In this context, "effectiveness" is defined as to what extent the measure reduces incidental catch of cetaceans; "cost" is defined as the initial cost or investment and any ongoing operational costs, including foregone catches.

Other technical options are currently under development and fishers and researchers in the field may develop new mitigation measures, so the list of measures is likely to increase over time. Each State may find it advantageous to implement the measures most suitable for its conditions and that reflect the specific needs of their fisheries. The list below should be considered neither prescriptive nor exhaustive. The IWC, FAO or other organizations should maintain a data base of measures that are in use or under development.

To reduce the incidental mortality of cetaceans in fisheries, it is essential to reduce (1) the number of entanglements or entrapments of cetaceans in fishing gear and/or (2) the mortality of cetaceans after capture. In many cases, especially with static fishing gears (e.g. bottom-set gillnets), the latter approach will not be feasible.

Acoustic Alarms

Concept: Deterring cetaceans from fishing gear by producing acoustic signals that alert or displace animals.

Effectiveness: Demonstrated to be effective in reducing incidental catches of harbor porpoises in demersal gillnet fisheries in the North Atlantic and North Pacific, and common dolphins in a drift gillnet fishery in the North Pacific. Effectiveness is unproven with other species. A variety of alarms are available; not all have been proven to be effective in reducing cetacean by-catches. Acoustic alarms may not eliminate by-catch completely, thus their use is not recommended for use with highly endangered populations or species.

Cost: High initial investment and moderate maintenance costs.

Time and Area Closures

Concept: Separate fishing effort from high densities of cetaceans in time and/or space.

Effectiveness: Demonstrated to be effective in reducing the by-catch of Hector’s dolphins in New Zealand . In general, area and seasonal closures may be effective if incidental catches are clustered and predictable, although displacement of fishing effort to other areas needs to be considered. To be effective, this approach requires information on the temporal and spatial distribution of fishing effort, cetaceans and by-catches. Fishing effort will likely be displaced from such areas and management actions should consider this displacement in an explicit fashion.

Cost: Variable, depending on the overlap of fishing effort and cetaceans and the dispersion of fishing effort in time and space. Costs may be high if fishing is excluded from profitable, intensively used areas.

Modifying Fishing Gear or Practices

Concept: Change the physical structure of fishing gear (e.g. mesh size) or the way in which it used (e.g. soak time) to effect reductions in incidental catches of cetaceans. In some extreme cases, it may be preferable to switch fishing gears entirely, to reduce or eliminate cetacean by-catches.

Effectiveness: Demonstrated to be effective in reducing mortality of pelagic dolphins in the ETP purse seine fishery for yellowfin tuna (see below). General effectiveness will depend on the species and fishery. May conflict with other objectives of fisheries management.

Cost: Unknown.

Releasing Cetaceans Alive

Concept: If cetaceans are incidentally captured alive, or escape entangled in gear, every reasonable effort should be made to ensure that animals are disentangled and released alive.

Effectiveness: Demonstrated to be effective with pelagic dolphins in the ETP purse seine fishery for yellowfin tuna; harbour porpoises, humpback, minke and right whales in herring weirs in the Bay of Fundy; and humpback whales in a variety of coastal fisheries in the NW Atlantic. Many cetaceans can be released alive from trap or purse seine fisheries. Cetaceans can be disentangled while entangled or while swimming freely, carrying gear.

Cost: Variable, depending on the effort required to locate and disentangle cetaceans.