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Wednesday, May 22, 2019

S6: Economic Strategies for Reducing Bycatch in Commercial and Recreational Fisheries

Session Chairs: Drew Kitts, NOAA/NMFS/Office of Science & Technology; Sabrina J. Lovell, NOAA/NMFS/Office of Science & Technology;

15:30 – 15:35

Overview of NMFS Workshop on Economic Aspect of Bycatch Reduction

Overview of Special Session S6: Economic Strategies for Reducing Bycatch in Commercial and Recreational Fisheries.

15:36 – 15:49  |  3570558

Fishery observers for reducing bycatch and discards in Greenland

Hunter Snyder1; JT Erbaugh1;
1Dartmouth College, Hanover, USA;

Globally, we do not know if fishing adheres fully to the law. Fish caught on accident or bycatch and fish thrown over board called discards have a cascading effect within fisheries, and are also a source of controversy in fisheries policy, law and enforcement. Measuring how effective enforcement measures are for reducing bycatch and discards is pivotal to understanding fisheries compliance with the law, and for developing strategies to reduce resource waste in fishery systems. In Greenland, more than 75% of all large-scale fishing is conducted without direct monitoring of a fishery observer aboard. While this sector creates about 75% of the value in Greenland ($52 million in 2017), little is known about the resource wastes associated with fishing, be it monitored or not. Using digital logbook records from all of Greenlands fisheries, we use matching techniques to process observations of trips from the last five years (2012-2017), with and without observers (N=5144). For each fishery, we present the likelihood of fishery observers driving bycatch and discards, as well as the effects of interaction terms such as haul time, vessel nation, gear type, season, and area. We also calculate the costs of the resource wastes that accue under the two enforcement scenarios of an observer aboard, or under standard, nonphysical control procedures. Our results clarify the costs and benefits of fishery observer programs designed for enforcement. We anticipate that that our methods will be of value to work on causal inference in the environmental social sciences and ongoing dialogue concerning the role of fishery observers in the montoring, control, and surveillance of fishing.

15:50 – 16:03  |  3593330

The sport fishing of totoaba: An alternative for small-scale fishers in the Upper Gulf of California?

Mónica Ruiz-Barreiro1; Alvaro Hernández2;
1Centro Interdisciplinario de Ciencias Marinas, La Paz, Mexico; 2Universidad Marista de Merida, Merida, Mexico;

The totoaba (Totoaba macdonaldi) is an endemic species of the Upper Gulf of California, and was declared by the Mexican government over-exploited and threatened in 1975. For more than 40 years, this species has been subject to illegal fishing, due to the high prices of its swim bladder (maw) in the Asian black market. In recent years, biological studies showed a recovery of its population, opening up the opportunity of legalizing the fishery. However, the poachers have used gillnets, which can trap the endangered vaquita (Phocoena sinus) as bycatch. Anticipating a potential disarray of small-scale fishermen of the Upper Gulf of California, in the event of legalization of commercial fishing and to reduce the threat of vaquita, conservationists have proposed the legalization of sport fishing as an alternative. The eventual sport fishing of totoaba could be practiced only with rods. In this study, a bioeconomic model is applied to elucidate the outcomes of this potential sport fishing of totaba. Our results show that the stock could maintain a safe level with a total annual catch of 960 tons, which at a catch rate of 0.8 fish per trip could be obtained with 480 fishermen. However, the benefits of this fishery are even lower than those obtained from sales of the swim bladder.

16:04 – 16:17  |  3660757

The exempted fishing permit conservation conundrum, and how to resolve it

Stephen M. Stohs1;
1Southwest Fisheries Science Center, La Jolla, US;

Exempted fishing permits (EFPs) are authorized by the Magnuson-Stevens Act (MSA) to support testing of fishing methods in locations where or during times when necessary research activities are normally prohibited. EFPs control potential conservation impacts through limits on fishing effort, which may include restrictions on gear, fishing days, number of vessels, times and areas open to fishing or other attributes of effort. Even with such controls, a question remains of whether any conservation impacts that occur as a result of EFP fishing effort will cause unacceptable harm to protected species of marine mammals, sea turtles or sea birds.

An EFP has been proposed to test shallow-set longline swordfish fishing (SSLL EFP) within the U.S. West Coast Exclusive Economic Zone (WC EEZ). Conservation groups have expressed concern over protected species interactions which might result if the EFP were allowed to proceed. Longline fishing is prohibited inside the WC EEZ, creating a conundrum where the EFP effort needed to determine conservation risk can never be allowed due to fears that the unknown conservation impacts may prove unacceptable.

A history of observer data collected for the Hawaii longline fishery supports a Bayesian data analysis to predict the probability of interactions with species of concern which might result if the SSLL EFP is authorized. The Hawaii data provides a basis for developing informative priors on the interactions which might result, with planned EFP effort used as a proxy for effort which would occur if the EFP proceeds. Inferred interaction and mortality rates combined with planned EFP effort enable producing informative prior predictive distributions that can be used to quantify the probability that protected species interactions will exceed prescribed limits. New data from conducting the EFP can be used to update from the informative prior distributions to posterior predictive distributions which quantify conservation impacts conditional on the level of effort. By providing a methodology for predicting unknown conservation impacts for a prescribed amount of EFP effort, the Bayesian approach can help resolve the EFP conservation conundrum.

16:18 – 16:31  |  3577048

Reducing bycatch with catch shares: The U.S. pelagic longline fishery individual bluefin quota program

George Silva1;
1NOAA Fisheries, Silver Spring, MD, USA;

NOAA Fisheries implemented a unique catch share program in 2015 for Atlantic bluefin tuna caught by the U.S. pelagic longline fleet. This pelagic longline fleet primarily targets swordfish, yellowfin tuna, and bigeye tuna, but also incidentally catches bluefin as bycatch. Any bluefin interactions with pelagic longline gear are incidental to other directed fishing, and regulations have been designed to discourage interactions and to minimize bluefin bycatch. The Individual Bluefin Quota (IBQ) catch share program is designed to provide individual vessel accountability for bluefin catch (landings and dead discards) and incentivizes the pelagic longline fishery to minimize interactions with bluefin. The IBQ Program also provides flexibility in the quota system by allowing pelagic longline vessel owners to obtain quota from other vessel owners, or from Purse Seine category participants, through IBQ leasing. This presentation compares the pelagic longline fishery prior to the implementation of the IBQ Program to the fishery under the IBQ Program, to evaluate the effectiveness of this catch share program. Changes in the number of fleet participants, effort, catch, bycatch, revenues, costs, and IBQ leasing will be examined.

16:32 – 16:45  |  3557562

Using incentives to reduce bycatch and discarding: Results in the west coast groundfish catch share program

Lisa Pfeiffer1;
1NOAA Fisheries NWFSC, Seattle, WA, USA;

Catch share management was implemented in the bottom trawl sector of the West Coast Groundfish fishery in 2011 to address a range of issues including high bycatch and discard rates. The catch share program was designed to remove the incentives to discard through full catch accounting, tradeable quotas, increased flexibility in fishing, and penalties for catch overages. We assess the effectiveness of the program in meeting its environmental objectives by comparing discard weights, proportions, and variability from 2004 to 2010 with 20112016. We analyzed these metrics for species managed using quota, including historically overfished stocks, as well as for non-quota species caught in the fishery. Discard amounts decreased over time for all species and declined to historic lows after the implementation of the program, remaining low through 2016 with much less inter-annual variability. Mean annual discards of two highly-targeted quota species, sablefish, and Dover sole, showed the greatest decreases, falling by 97% and 86%, respectively. The discard proportion of overfished quota species fell by 50% on average. The unanticipated decline in discards of non-quota species as well as the decreased variability in discard amounts for all species indicates that the incentives produced by catch share management provided additional ecosystem benefits.

16:46 – 16:59  |  3660036

Retrospective analysis of US measures implemented to protect North Atlantic right whales

Kathryn Bisack1; Gisele Magnusson2;
1NOAA/NMFS/NEFSC, Woods Hole, MA, US; 2Fisheries and Oceans Canada, Ottawa, Ontario, Canada;

The North Atlantic right whale (NARW) occurs primarily over the continental shelf of the United States (US) and Canada and is one of the most endangered large whales; the most recent population estimate is 440 animals. The leading causes of known mortality are entanglement in fishing gear and vessel strikes. In US waters between 1996 and 2008, measures to reduce the risk of entanglement focused on spatially and temporally specific requirements. Static closures began in 1996, while real-time spatial management measures were added in 2002 in the form of a Dynamic Area Management (DAM) zone triggered by a reliable report of three or more NARWs. In 2009, DAM was eliminated in favor of gear requirements throughout northeast US waters. This range of policy instruments provide an opportunity to evaluate the effectiveness of alternative measures that both avoid and minimize entanglement encounters. Using monthly density estimates, we evaluate the amount of protection provided to the NARW by the alternative management measures, as a measure of benefits. The risk of entanglement is analyzed for 1996 to 2016 to comprehensively compare policy instruments. Compliance impacts are considered for technology standards. Spatially distributed fishing catch and effort data is used to evaluate private costs. Private and public sector tradeoffs in relation to whale detection sampling and the cost of protection measures to the fishing industry are assessed. The results may assist real-time management responses to fast or short-term shifts in habitat use by marine species.


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