Killer whales (Orcinus orca) are cosmopolitan, apex predators that sometimes interact with commercial fisheries. These fishery interactions can affect killer whales, sometimes harmfully, and cause negative socioeconomic consequences for the fishing industry. This review examines global trends in commercial fishery interactions with killer whales by analyzing 69 articles published between 1963 and 2024. These articles noted interactions between killer whales and fisheries in all oceans, but especially at high latitudes. Most documented interactions involved the depredation of longlines. Killer whales have been observed depredating a minimum of 30 species, mainly large fish such as tunas (Thunnus spp.). Bycatch, injuries, fishers’ retaliatory measures, and artificial provisioning impacted killer whales that interacted with fisheries. Various mitigation measures have been tested with mixed success. This review outlines policy options to address interactions between killer whales and fisheries and identifies existing knowledge gaps.

Data and insights from fishers are essential sources of information to advance understanding of fishery and ecosystem dynamics. Incorporating fisher and industry knowledge holds prospects for improving marine science and fisheries management. We address cooperative research in the context of collaboration between fishers, scientists, industries, universities, and agencies to develop applied research to understand marine ecosystems, inform fishery management, enhance sustainability, govern resource use, and investigate social-economic dynamics. We leverage the insights of more than 100 research scientists, fisheries managers, industry representatives, and fishers to outline actionable recommendations for effective approaches and mechanisms to integrate industry data, perspectives, and insights in fisheries science. We also highlight opportunities and address challenges and limitations to such collaboration.

Because fish stocks often straddle state, national, and international boundaries, there is a need to coordinate fishery management across jurisdictions. This is particularly important when the abundance or spatial distribution of the stock varies through time. This is best achieved when management objectives and strategies align, and there is coordinated decision‐making and catch accounting among jurisdictions such that each fish stock is managed over its full geographic range. However, legal constraints or differing management objectives may not permit such coordinated decision making and policy development. This study introduces a framework for effectively simulating fleet dynamics, fishery quota allocation, and the implications of alternative management strategies while allowing for determination of economically optimal management approaches at the community level. As a case study, an agent‐based model (ABM) was developed to examine the interplay between transboundary management scenarios on the economic viability of a nascent Alaska state‐waters trawl fishery for walleye pollock (Gadus chalcogrammus) in the Gulf of Alaska, given a longstanding federally managed fishery. Under conditions characteristic of the recent past, the management strategy that produced the best overall improvements, relative to status quo, involved a scenario that allows for community‐based cooperatives in federal‐waters and an open access strategy in state‐waters. This case study allows us to demonstrate more generally how using an ABM allows for quantifying the impacts of and informing managers on anticipated, and novel, results of alternative management strategies for complex socioecological systems before implementation.

The goal of this study was to determine whether humpback whale Megaptera novaeangliae depredation on hatchery-released juvenile salmon is affecting the economic productivity of hatcheries in Southeast Alaska. From 2010 to 2015, observers monitored five release sites in Chatham Strait, Alaska. Humpback whales were present at the release of 23 of 54 salmon cohorts (defined by release year, species, site, and release strategy). A linear regression model was used to determine whether humpback whale presence at a cohort release affected the proportion of that cohort that survived to harvest. The model included covariates related to management and environmental conditions. The lost fishing revenue for each cohort was determined using the model-predicted marine survival with and without humpback whales and the average commercial value of the adult salmon. Marine survival of Coho Salmon Oncorhynchus kisutch was significantly lower for cohorts with humpback whale depredation, resulting in an estimated US$1 million of lost revenue per year (95% confidence interval = $747,500-1,205,000) associated with whale depredation (23% of observed ex-vessel fishing revenue from these Coho Salmon cohorts). No significant effect was observed for depredation losses to releases of Chum Salmon O. keta or Chinook Salmon O. tshawytscha, which tended to have low marine survival even in years of no observed whale depredation, possibly due to compensatory depredation from other sources. Despite Chum Salmon having the highest rates of whale depredation, there is no evidence to suggest that preventing humpback whale depredation alone would be sufficient to increase marine survival and fishing revenue for that species, although it may be necessary in concert with other measures.

This paper compares observations of commercial fishermen with a fishery-independent survey, and explores putative relationships between characteristics of fishing operations and incidental catch in the Pacific halibut fishery in Southeast Alaska. Results from a multiple factor analysis demonstrate statistically significant relationships between fishing characteristics and the incidental catch of various species. Results from a proportional odds logistic regression model indicate the presence of a strong unavoidable component of incidental catch in the halibut fishery. Consequently, patterns of incidental catch in this fishery generally paralleled patterns of incidental catch in a fishery-independent stock assessment survey that uses similar gear. This suggests that increased onboard monitoring of this fleet by cameras or human observers is unlikely to reveal broad trends in incidental catch that are not already apparent in the fishery-independent stock assessment survey. Nevertheless, weaker statistically significant relationships in the model indicate that incidental catch may be influenced by observable and controllable characteristics of fishing operations (e.g., fishing grounds, season, vessel length, gear configuration). This suggests a proportional odds model like the one presented in this paper could be used to generate operation-specific estimates of incidental catch by species from incidental catches observed in fishery-independent surveys based on known characteristics of fishing operations.

In fisheries management, ex-ante analysis of fishermen’s preferences can provide reliable insights into specific characteristics of regulatory alternatives that are desirable, objectionable, or important, in the judgement of fishermen. This knowledge could facilitate consideration by fishery managers of additional regulatory alternatives with high likelihoods of meeting program objectives, minimal disruption to fishing operations and lifestyles, and high levels of acceptance and compliance from the fishing fleet. In this case study, we interviewed Pacific halibut fishermen (n = 76) in four communities across Southeast Alaska, to document their preferences about different types of data collection methods on their vessels. We demonstrate how to use interviewing to gather preference data from a relatively small group of fishermen and get a reliable snapshot of preferences across an entire region. Pairwise comparisons from interviews were analyzed using a three-stage analytic hierarchy process model. Results characterize the variability of fishermen’s preferences about data collection methods.

FisheriesVolume 43, Issue 1 p. 26-30 Essay Will Alaska's Fisheries Regime Prove Resilient? Kenai River Fishery Management as a Model for Adaptive Governance James E. Powell, James E. Powell School of Arts and Sciences, University of Alaska Southeast, 10601 Horizon Drive, Juneau, AK, 99801.Search for more papers by this authorMark S. Wipfli, Mark S. Wipfli U.S. Geological Survey, Alaska Cooperative Fish and Wildlife Research Unit, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AKSearch for more papers by this authorKeith R. Criddle, Keith R. Criddle College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, AKSearch for more papers by this authorErik R. Schoen, Erik R. Schoen Alaska Cooperative Fish and Wildlife Research Unit, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AKSearch for more papers by this author James E. Powell, James E. Powell School of Arts and Sciences, University of Alaska Southeast, 10601 Horizon Drive, Juneau, AK, 99801.Search for more papers by this authorMark S. Wipfli, Mark S. Wipfli U.S. Geological Survey, Alaska Cooperative Fish and Wildlife Research Unit, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AKSearch for more papers by this authorKeith R. Criddle, Keith R. Criddle College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, AKSearch for more papers by this authorErik R. Schoen, Erik R. Schoen Alaska Cooperative Fish and Wildlife Research Unit, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AKSearch for more papers by this author First published: 22 February 2018 https://doi.org/10.1002/fsh.10022Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Volume43, Issue1January 2018Pages 26-30 RelatedInformation

After record salmon bycatch in 2007 by the Eastern Bering Sea and Aleutian Islands fishery for walleye Pollock, the North Pacific Fishery Management Council (NPFMC) concluded that additional management strategies were necessary to further control salmon bycatch. The Preliminary Preferred Alternative (PPA) was selected in April 2009 and implemented in January 2011 as Amendment 91. In this paper, we present the original comprehensive bycatch credits allocation and trading plan as designed by the first author as commissioned by the Alaskan Pollock Fleet for Chinook salmon, the Comprehensive Incentive Plan (CIP). The CIP, which uses individual (vessel-level) tradable encounter credits (ITEC), included incentives that make up the backbone of Amendment 91/PPA. While salmon bycatch has been reduced since the implementation of the PPA, the current amendment does not have individual vessel incentives that vary with the vulnerability of salmon populations. The CIP approach presented here provides robust vessel-level incentives to reduce Chinook salmon bycatch under all levels of salmon abundance, but particularly when salmon populations are at their lowest levels and are most vulnerable. The specific financial incentive structure in the full plan, with trading of by-catch liabilities among vessels, can be applied well in other fisheries where bycatch threatens both sustainability and profitability.

The World Ocean presents many opportunities, with the blue economy projected to at least double in the next two decades. However, capitalizing on these opportunities presents significant challenges and a multi-sectoral, integrated approach to managing marine socio-ecological systems will be required to achieve the full benefits projected for the blue economy. Integrated ecosystem assessments have been identified as the best means of delivering the information upon which marine resource management decisions can be made. By their nature, these assessments are inter-disciplinary, but to date have mostly focused on the natural sciences. Inclusion of human dimensions into integrated ecosystem assessments has been lagging, but is fundamental. Here we report on a Symposium, and the articles emmanating from it that are included in this Theme Set, that address how to more effectively include human dimensions into integrated ecosystem assessments. We provide an introduction to each of the main symposium topics (governance, scenarios, indicators, participatory processes, and case studies), highlight the works that emerged from the symposium, and identify key areas in which more work is required. There is still a long way to go before we see end-to-end integrated ecosystem assessments inclusive of all the major current and potential ocean use sectors that also encompass multiple aspects of human dimensions. Nonetheless, it is also clear that progress is being made and we are developing tools and approaches, including the human dimension, that can inform management and position us to take advantage of the multi-sectoral opportunities of sustainable blue growth.

In a mixture of individuals from different populations, population proportions and individual identities are estimated by comparing the characteristics of individuals in the mixture to a (usually) genetic baseline of population-specific characteristics. Using simulated data sets, we examined the performance of a generic mixture analysis that incorporated data on non-baseline character state frequencies. Population-specific state frequencies of non-baseline characters were well-estimated in many scenarios. We found benefits of incorporating non baseline characters in mixture analysis; both individual assignments and estimates of population proportions were improved. However, both the sample size and the quality of the baseline data were more important. We did not see any improvement in estimating baseline character state frequencies even when highly informative non baseline data was used. Our results suggest that non-baseline data might improve mixture analyses, and we note that population-specific estimates of non-baseline character state frequencies are often useful in and of themselves.

Contribution of the eight north-eastern states of India towards national fish production is only 5.9% despite the vast resources available in the region. There is a clear disparity in the total fish production vis-a-vis the potential in these states of India. This paper estimates the growth and instability of fish production in the north-eastern states of India relating the performance to the resource availability in the region and suggests strategies for enhanced fish production. Compound growth rates and Coppock’s instability index were used to determine the growth and performance of fish production in these states. Assam emerged as the state producing the maximum quantity of fish among the eight north-eastern states during the period 1999-2010. The share of Tripura was 16% and only 13% of the total fish production was contributed by the other six states. In terms of productivity, Manipur followed by Tripura and Mizoram head the table. There is considerable scope for improving the performance of fisheries sector in the north-eastern states of India by adoption of appropriate technologies and up-scalable models.

Seasonal and annual marine growth of chum salmon (Oncorhynchus keta) from Fish Creek, Alaska, during 1972-2004 and from Quilcene River, Washington., during 1973-2004 were examined in relation to abundances of chum salmon and pink salmon (O. gorbuscha) and climate indices from that period. Pink salmon abundance indices were included in the analysis because of evidence for density-dependent effects on chum salmon growth and survival. In linear regression models, growth was negatively related to abundance of chum salmon or to the combined abundance of pink and chum salmon during the middle juvenile (July-Sept), 1st immature, 2nd immature, and maturing stages for the Fish Creek chum salmon and the 1st immature, 2nd immature, and maturing stages for Quilcene River chum salmon, indicating possible density-dependent effects on growth. Mid-juvenile and maturing growth models for the Fish Creek chum salmon and the maturing growth model for Quilcene River chum salmon performed well in model validation, when model predictions were tested against 20% of the data that were not used for model specification, and provided insight into the effects of climate and abundance on growth of chum salmon from 1972 to 2004.

Alaska is the world's principal supplier of Sablefish Anoplopoma fimbria, a buttery-flavored whitefish greatly prized in Japan. Sablefish are distributed from Baja California to western Japan, but the majority of commercial catches are from the Gulf of Alaska and the Aleutian Islands off Alaska. The volume and value of landings of this long-lived demersal fish are comparable to those of the well-known Pacific Halibut Hippoglossus stenolepis. As with Pacific Halibut, Alaska region catches of Sablefish are managed under an individual fishing quota (IFQ) program implemented in 1995. We present a simultaneous-equation market model for Sablefish and use it to examine the linkages between landings volume and exvessel prices and revenues, including the sensitivity of Alaska exvessel prices and revenues to changes in landings, the implementation of IFQs, and changes in the Japanese economy. The model simulations indicate that markets could absorb substantially more Sablefish than can be sustainably harvested from the current stock of Sablefish in the Alaska region. However, sluggishness in the Japanese economy has resulted in overall downward pressure on Alaska region Sablefish exvessel prices. The model simulations indicate that the implementation of IFQs in this fishery significantly increased exvessel revenues as a consequence of the longer seasons that resulted from the end to the "race for the fish." In addition, we find that implementation has helped buffer the fishery against revenue losses associated with reduced catch limits triggered by the decline of Sablefish biomass in the Alaska region.

Ecosystem-based fisheries management requires the development of physical and biological time series that index ocean productivity for stock assessment and recruitment forecasts for commercially important species. As recruitment in marine fish is related to ocean condition, we developed proxies for ocean conditions based on sea surface temperature (SST) and biometric measurements of chum salmon (Oncorhynchus keta) captured in the walleye pollock (Gadus chalcogrammus) fishery in the eastern Bering Sea in three periods (July 16-30, September 1-15 and September 16-30). The main purpose of this paper was to evaluate Pacific salmon (Oncorhynchus spp.) growth as a possible indicator of ocean conditions that, in turn, may affect age-1 walleye pollock recruitment. Marine growth rates of Pacific salmon are the result of a complex interplay of physical, biological and population-based factors that fish experience as they range through oceanic habitats. These growth rates can, therefore, be viewed as indicators of recent ocean productivity. Thus, our hypothesis was that estimated intra-annual growth in body weight of immature and maturing age-4 male and female chum salmon may be used as a biological indicator of variations in rearing conditions also experienced by age-0 walleye pollock; consequently, they may be used to predict the recruitment to age-1 in walleye pollock. Summer SSTs and chum salmon growth at the end of July and September explained the largest amount of variability in walleye pollock recruitment indicating that physical and biological indices of ocean productivity can index fish recruitment.

Resource management agencies are required to consider stakeholder input in the selection of preferred alternatives for proposed actions. Not only do stakeholders contribute unique perspectives on the impact of alternative actions and the desirability of various policy objectives, including stakeholders in the decision process adds to the perceived legitimacy of those decisions. However, gathering stakeholder input and incorporating it into decisions can be difficult. We solicited public input on research needed to improve marine resource management decision-making for the Aleutian Islands region. Stakeholders and an expert panel were asked to use the analytical hierarchy process to rank those research needs. Spearman rank correlation tests were used to search for statistically significant differences in the rank orderings between stakeholders and the expert panel. A high level of association was found between rankings by an expert panel and those by stakeholders. Moreover, the rank orderings were robust to the inclusion or exclusion of interest-group subsets of the stakeholders and expert panel. The expert panel and stakeholders assigned highest priority to new research designed to increase basic knowledge of the Aleutian Islands marine ecosystem. Agreement between stakeholder and expert panel rankings was closest for the most and least important research needs; most substantial differences in the rankings involved research needs identified as moderately important. These results suggest that an expert panel may provide input comparable to that which could be obtained from engaging in a more extensive stakeholder process. Furthermore, these results suggest that the analytical hierarchy process can serve as a useful mechanism for organizing stakeholder input for environmental planning and resource management.

The eastern Bering Sea fishery for pollock, Theragra chalcogramma, yields a first wholesale value over $1 billion; it is the premier US fishery. While there is general agreement that this fishery is managed under principles that foster sustainability, the stock is not wholly contained within the US Exclusive Economic Zone. Management of straddling stocks can be highly contentious, particularly when, as is the case for pollock, the spatial distribution varies considerably. When the center of pollock abundance shifts to the northwest, an increased portion of the stock is exposed to harvest by vessels operating in the Russian Federation Exclusive Economic Zone. The lack of coordination in the management of this transboundary stock presents a risk that is not reflected in current management strategies. We use a multiple product/multiple market bioeconomic model to characterize optimal cooperative and non-cooperative harvest management strategies from the perspective of US and Russian pollock fisheries under environmentally induced changes in pollock abundance and the distribution of that abundance.