How Many Species of Snakehead Fishes are in the USA? by Don Orth

The summer of 2002 was the summer of the snakehead — the first exposure with these exotic fishes for many of us.  It began with the first appearance of the Northern Snakehead Channa argus in a small pond in Crofton, Maryland.   Snakehead fishes are air-breathing freshwater fishes in the family Channidae. The genus Channa includes snakeheads of Asia, Malaysia, and Indonesia, and the genus Parachanna occur in Africa. In their native range, they are important food fish. Elsewhere, snakeheads are popular in live food fish and aquarium trades and many species are cultured for food.  Recently sport fishing for snakeheads has grown in popularity. After the establishment of the Northern Snakehead in the Potomac River, it spread to other tributaries of Chesapeake Bay and scientists are concerned about its potential to spread into all the Great Lakes except Superior (Kramer et al. 2017; Love and Newhard 2018).  In all habitats it colonizes, scientists will need to evaluate its potential to threaten native fishes, the recreational fishing industry, and aquatic ecosystems, all of which will cost time and money.

Top Ten Little Known Facts about the Snakehead Fish. 

(The Late Show with David Letterman, Dolin 2003).

10.       The fish is 50 percent snake, 50 percent head. 

9.         Mortal enemy is the fishhead snake.

8.         High-protein diet of fish and frogs means slim look for summer. 

7.         They love kids.

6.         Bush promised to find and catch them…of course we’ve heard that before. 

5.         Fans of the snakehead fish are known as snakehead-heads.

4.         Available for a limited time at participating Red Lobsters. 

3.         It’s very popular with lawyers, am I right people?

2.         Developed by the government to distract people from the whole Cheney-Halliburton thing. 

1.         It’s the result of a drunken genetic engineer and a dare. 

Many initial fears were overblown or laughed off by comedians who managed to pass on misinformation about the snakehead.   This infographic in The Onion from 2002 joked about the  snakehead signing movie deals left and right.  Snakehead fish played a feature role in four movies, including Snakehead Swamp, Frankenfish, Snakehead Terror, and Swarm of the Snakehead. But the movie hype only distracted us from learning more about the potential for the snakehead to cause harm. 

Invasive species are serious concerns as our global society facilitates transcontinental introductions.  An invasive species is "an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health" as per Executive Order 13112: Section1. Definitions. Defining harm is the most difficult prerequisite to devising management interventions. Charles Elton introduced the militaristic "invasion" metaphor to describe exotic plants and animals in the 1950s and we’re often stuck with a Mission Impossible situation. Julian Olden, Professor in the School of Aquatic and Fishery Sciences at the University of Washington, refers to this approach as the "guilty even when proven innocent."  

The snakehead family of fishes have been federally regulated since 2002 when they were listed as injurious wildlife under the Federal Lacey Act (18 USC 42), which makes it illegal to import injurious wildlife into the United States or transport between the listed jurisdictions in the shipment clause (the continental United States, the District of Columbia, Hawaii, the Commonwealth of Puerto Rico, and any possession of the United States) without a permit. An injurious wildlife listing would not prohibit intrastate transport or possession of that species within a State where those activities are not prohibited by the State. See also: Injurious Wildlife: A Summary of the Injurious Provisions of the Lacey Act. 

The first step in determining harm is to map out the occurrence and consider where and what other species it might influence.  But this is not a simple step because there are five, not one, species of snakehead fish known to occur in USA (Benson 2019).

Blotched Snakehead Channa maculata is native to southern China and Vietnam.  It was the first snakehead introduced to the island of O’ahu, Hawaii in the late 1800s.  It became established there in ditches, ponds, and reservoirs.  

from USGS

Giant Snakehead Channa micropeltes is tropical-subtropical species native to India, southeast Asia, including the peninsular Malaysia.  It has been collected in six states presumably due to aquarium releases (Benson 2019). 

Giant Snakehead Source

Giant Snakehead juvenile. Source

Northern Snakehead Channa argus is a temperate species native to the Korean peninsula and eastern rivers of China and Russia.  Northern Snakehead have been collected from 13 states and the District of Columbia (Benson 2019).   Northern Snakehead has established populations from Arkansas, Virginia, Maryland, Delaware, New Jersey, and New York. History of introductions of the Northern Snakehead is chronicled in Benson (2019).  Populations originated from escapees from fish culture ponds (banned in 2002), live food markets, and human assisted introductions.

Northern Snakehead.  Illustration by Susan Trammell. Source

Chevron Snakehead Channa striata is a a warm temperate species native to Pakistan and parts of southeast Asia.  It was introduced into Hawaii as broodstock for commercial aquaculture. 

Chevron Snakehead.  USGS

Bullseye Snakehead Channa marulius is native to tropical and warm temperate regions of southeast Asia, southern China, and Pakistan.  The Bullseye Snakehead has been established in southern Florida since at least 2000, but has not colonized Everglades National Park or Big Cypress Natural Preserve.  

Bullseye Snakehead.  (c) Michigan Science Art.  Source.

It helps that we know more about the distribution of these five snakehead fishes.  Context is everything.   Before snakehead fish were banned for import, live snakeheads were common in live-food markets where they could easily be released to create fisheries or for prayer release ceremonies. The Buddhist practice known as ‘live release’, ‘fang sheng’, ‘mercy release’, and ‘prayer animal release’, entails the release into the wild of captive animals and particularly those destined for slaughter. However, this ancient practice would release animals to their native habitats (Everard et al. 2019).   

Given the multiple species and settings for introduction, we need to treat each case and context according to best information regarding harm and feasible management policies (SPDC 2014; Orth 2019).  To develop and enact sensible policies, it is crucial to consider two philosophical questions: (1) What exactly makes a species native or exotic, and (2) What values are at stake? (Woods and Moriarty 2001). Humans are important vectors so the solution to widespread dispersal must focus on human behavior. Importing live snakeheads is prohibited as is their interstate transport.  Maryland and Virginia prohibit possession of live snakeheads.  Penalties for transporting live Snakehead should be continued and communicated widely.  Fishing and bow fishing have potential to reduce local abundance of Northern Snakehead in Potomac tributaries.   Whether we can eat our way out of the snakehead abundance is yet to be seen, though plenty of recipes will work for this tasty fish.    

Snakehead Cakes prepared by Alewife Restaurant, Baltimore.  Photo by D.J. Orth.

References

Benson, A.J. 2019. Snakehead fishes (Channa spp.) in the USA.  Pages 000-000 in D. Chapman and J. Odenkirk, editors.  First International Snakehead Symposium, American Fisheries Society Symposium 89.  Bethesda, Maryland.  

Dolin, E.J. 2003.  Snakehead: Fish out of water.  Smithsonian Books, Washington, D.C.

Everard, M., A.C. Pinder, R. Raghavan, and G. Kataria. 2019.  Are well-intended Buddhist practices an under-appreciated threat to global aquatic biodiversity?  Aquatic Conservation Marine and Freshwater Ecosystems 29:136-141. 

Kramer, A. M., G. Annis, M. E. Wittmann, W. L. Chadderton, E. S. Rutherford, D. M. Lodge, L. Mason, D. Beletsky, C. Riseng, and J. M. Drake. 2017. Suitability of Laurentian Great Lakes for invasive species based on global species distribution models and local habitat. Ecosphere 8(7):e01883.

Love, J.W., and J.J. Newhard. 2018. Expansion of Northern Snakehead in the Chesapeake Bay watershed. Transactions of the American Fisheries Society 147:342-349.

Orth, D.J. 2019.  Socrates opens a Pandora’s Box of Northern Snakehead issues.   Pages 000-000 in D. Chapman and J. Odenkirk, editors. First International Snakehead Symposium, American Fisheries Society Symposium 89.  Bethesda, Maryland.  

Snakehead Plan Development Committee (SPDC). 2014. Draft National Control and Management Plan for Members of the Snakehead Family (Channidae).Submitted to the Aquatic Nuisance Species Task Force.  https://www.anstaskforce.gov/Species%20plans/SnakeheadPlanFinal_5-22-14.pdf Accessed July 5, 2018.

Woods, M., and P. Moriarty. 2001. Strangers in a strange land: The problem of exotic species. Environmental Values10:163-191.

Women and Fishing, by Don Orth

Men and women use natural resources in different ways and may be differentially influenced by fisheries management policies.  Preferences and resource dependencies lead to some gender stereotypes about fishing.  In subsistence and commercial fisheries, catching of fish is often male dominated whereas the processing and marketing sectors are female dominated (Harper et al. 2017).  Yet, even these generalizations are misleading given the lack of attention to gender roles in fisheries science.  Few studies have been done comparing male and female motivations and preferences in recreational angling (Toth and Brown 1997; Schroeder et al. 2006). In the US, approximately 27% of anglers are female which is unchanged over twenty years (U.S. Fish and Wildlife Service 2012).  Marketing and fisheries management in the US has focused more on male motivations and preferences.  One failed attempt to market pink fishing reels failed to “Know Your Customer” (Merwin 2010).  The gender gap in participation in recreational fishing is likely tied to inappropriate avenues for socialization into male dominated sports (Carini and Weber 2017). 

Globally, women comprise about 47 per cent of the 120 million people who work in the capture fisheries and post-harvest sectors (Montfort 2015).   While women are involved in the fishing, farming, processing, trading and selling of fish, their role is often overlooked in decision making for cultural reasons. For example, many cultural constructions in rural Bangladesh undermine the capacity of women to aspire to leadership roles and raise their voice to male power (Deb et al. 2015).  However, the temporary departure of men creates more socio-political space for fisherwomen to take on additional roles and responsibilities.  In West African regions, women control the marketing and processing sectors and have taken on larger roles as owners of boats, nets, and fishing equipment (Bennett 2005; Walker 2010). In some countries, women are not allowed to go to sea, or own a fishing business; women are often the invisible fishing fleet.  The Beijing Declaration and the Platform for Action, adopted unanimously by 189 countries, is an agenda for empowerment of women.

Today in many small-scale fisheries, women are important fishery workers, but invisible and often underpaid (Montfort 2015). In Bangladesh, girls and women are a very cheap labor source for shrimp processing factories (Deb et al. 2015).   Fisheries management policies are set by governance bodies that exclude women (Baker-Médard 2016). The organization, Gender in Aquaculture and Fisheries, is devoted to giving “greater visibility to and increase awareness of the importance of incorporating gender and more particularly women in fisheries and aquaculture interventions.”

 

Rana Tharu women go fishing in southwest Nepal.  CC-BY-NC-SA   Source.

Timucua women fishing1562.  Drawing by Jacques Le Moyne.  CC-BY-NC-SA.  Source.

Women net fishing Madagascar by Rod Waddington  CC-BY-SA.  Source.

Commercial fishing fleets are overwhelmingly male dominated with fewer than 4% of commercial fishing licenses issued to women in Oregon and Washington states.  Yet women contribute to resilient communities by caring for family and maritime household and increasingly women play a significant role in science, fisheries management, policy, and decision making (Calhoun et al. 2016).  The following quote is from participant in an oral history project.

“I used to go to groundfish management team meetings 25 years ago, and if there was one woman scientist in the groundfish management team it was a big deal. And now you see women are the chairs of the groundfish management team. So seeing changes, growth of women in both management and in science. Although I know those areas are still a challenge too. And then the rise of women participating in the decision-making process.”

Though sometimes invisible, women are slowly changing the world of fishing by breaking the stereotypes. Here I share a few examples on women making a substantial impact through their passion toward fishing.  These examples demonstrate women who loved and valued what they did.  If the paucity of female role models discourages females from seeing the relevance of fishing to them, these examples should inspire.

Georgina Ballantine with 64 pound Atlantic Salmon from River Tay, Scotland.  Photo from Glendelvine. 

Joan Wulff was introduced to flyfishing by her father when she was ten.  She won several flyfishing accuracy championships before winning the 1951 Fishermen’s Distance competition against all-male competitors. She became the first female spokesperson for Garcia Corporation in 1959 and advocated for women anglers in her writings for Outdoor Life and Rod & Reel.    Today many females are engaged in the sport of fly fishing. Joan Wulff participated in many distance casting events and also did trick casting.   She snapped a cigarette from the mouth of Johnny Carson on the TV show “Who Do You Trust?” (Fogt 2017).  Watch this video narrated by Joan Wulff to learn more about her technique. Starting in 1978, Joan Wulff opened a fly casting school on the Upper Beaverkill River in New York.  Joan Wulff’s Fly-Casting Techniques, published in 1987, and Joan Wulff’s New Fly-Casting Techniques, published in 2012, are classic guides to learning her techniques. When asked about her favorite fish, she would respond “whatever I’m fishing for“ and her favorite place to fish  was “wherever I am.”

Photo of Eugenie Clark spearfishing.   Photo from Mote Marine Lab.

Eugenie Clark (1922-2015) was zoologist at a time when the field was male dominated. In her first book, Lady with a Spear, she wrote of her expeditions to the West Indies, Hawaii, Guam, Palaus, and the Red Sea, and early research trials on vision and behavior in gobies, puffers, triggerfishes, and sharks. Eugenie Clark became a self-taught expert in the art of throwing a cast net, and catching fish with both wooden handled harpoons and spear guns. She pioneered research on behavior of sharks and conducted numerous submersible dives around the world and founded the Mote Marine Lab before becoming a professor at the University of Maryland.  A timeline of her accomplishments appeared in the Herald Tribune.

 

Betty Bauman is the founder and CEO of Ladies, Let’s Go Fishing!(R). Betty created “The No-Yelling School of Fishing.”  Most avid bass anglers can identify Roland Martin, Bill Dance, and Jimmy Houston, who dominated competitive bass fishing in the first decade of B.A.S.S. and have had TV fishing shows for decades.    But most females won’t identify with the three male legends. Kim Bain-Moore began competing in bass tournaments at age 19 and in 2009 became the first woman to compete in the Bassmaster Classic tournament.  But female participation in competitive bass fishing never took off as expected.  Fewer that 1 in 5 readers of Field & Stream, Outdoor Life and Bassmaster magazines are female (Carini and Weber 2017).  Yet the future growth of sport fishing will rely on female anglers, instructors, and guides.  There are signs of change since Betty Baumann started offering Ladies Let’s Go Fishing! to expose women to a non-intimidating atmosphere where they could learn fishing techniques.  Since the first program in 1997, over 8,000 participants have graduated from the Ladies, Let’s Go Fishing! Training.  In 2018,  the Lady Bass Anglers Association was formed to promote the Women’s Pro Bass Tour.   Wild River Press released Fifty Women Who Fish by Steve Kantner.  Today we see many more female fishing guides, fishing resources for female anglers, and female anglers on social media. Consider young writer and fishing guide, Ashley Rae, who operates She Loves To Fish, a fishing guide service focused on teaching women to fish.  

Today we are re-gendering many types of work and leisure activities.  The significant challenges that we face in freshwater and marine conservation at home and abroad will require input from all.  Rather than propagating stereotypes of fishing activities, we need to explore the participation across gender and other differences so we can do a better job evaluating outcomes of conservation for the well-being of all humans. 

References

Bennett, E. 2005.  Gender, fisheries and development.  Marine Policy 29:451-459. 

Buller, F. 2013. A list of large Atlantic Salmon landed by the ladies.  American Fly Fisher 39(4):2-21.

Calhoun, S., F. Conway, and S. Russell.  2016.  Acknowledging the voice of women: implications for fisheries management and policy.  Marine Policy 74:292-299.

Carini, R.M., and J.D. Weber. 2017. Female anglers in a predominantly male sport: portrayals in five popular fishing-related magazines.  International Review for the Sociology of Sport 52(1):45-60.

Clark, E. 1951.  Lady with a spear.  Harper Brothers. New York.  243 pp. 

Deb, A.K., C.E. Haque, and S. Thompson. 2015. ‘Man can’t give birth, woman can’t fish’: gender dynamics in the small-scale fisheries of Bangladesh.  Gender, Place & Culture 22(3):305-324. 

Fogt, J. 2017. Virtuoso.  Anglers Journal. 12 May.   Accessed at https://www.anglersjournal.com/freshwater/virtuoso on 21 June, 2019.

Harper, S., C. Grubb, M. Stiles, and U.R. Sumaila. 2017 Contributions by women to fisheries economies: Insights from five maritime countries. Coastal Management 45(2):91-106.

Klieber, D., L.M. Harris, and A.C.J. Vincent. 2014. Gender and small-scale fisheries: a case for counting women and beyond.   Fish and Fisheries 16(4):547-562.

Merwin, J. 2010.  Merwin:  Study says most women don’t like pink fishing gear.  Field & Stream, 24 May.   Available at https://www.fieldandstream.com/blogs/bass-fishing/2010/05/merwin-study-says-most-women-dont-pink-fishing-gear/  Accessed 20 June 2019.

Montfort, M.C. 2015. The role of women in the seafood industry.  Globefish Research Program Volume 119, FAO, Rome. 67 pp.  http://www.fao.org/3/a-bc014e.pdf

Baker-Médard, M. 2017. Gendering marine conservation: The politics of marine protected areas and fisheries access. Society & Natural Resources 30(6):723-737.

Schroeder, S.A., D.C. Fulton, L. Currie, and T. Goeman. 2006. He said, she said: Gender and angling specialization, motivations, ethics, and behaviors. Human Dimensions of Wildlife 11(5):301-315.  

Toth, J.F., Jr., and R.B. Brown. 1997.  Racial and gender meanings of why people participate in recreational fishing.  Leisure Sciences 19:129-146.

U.S. Fish and Wildlife Service. 2012.  2011 National Survey of Fishing, Hunting, and Wildlife-Associated Recreation. Available at: http://www.census.gov/prod/2012pubs/fhw11-nat.pdf (accessed 18 June 2019).

Walker, B.L.E. 2001.  Sisterhood, and seine-nets: engendering development and conservation in Ghana’s marine fishery. The Professional Geographer 53(2):160-177.

 

What Fish Should I Eat? by Don Orth

Fisheries and aquaculture provide protein for a quarter of the world’s population and livehoods for 59.6 million workers. Fish provide a high-quality, easily digested animal protein with essential amino acids, fats, and micronutrients. Greater consumption of fish is associated with a lower risk of dementia, cognitive decline, and cardiovascular disease (Bakre et al. 2018; Marshall and van der Meij 2018).  Eat more fish - it's good for you!  Yet, the diversity of fish and types of fishing makes the selection of what fish to eat more complicated. 

Tuna is a popular food fish worldwide.  Photo by Ashbridge Studios, CC BY-NC-ND 2.0.  Source

One of many challenges to reducing hunger and malnutrition is to eliminate overfishing and delivering seafood in sustainable manner that does not further contribute to climate change.  Globally, 67% of assessed fish stocks are within biologically sustainable levels, which means they are at or above the level associated with maximum sustainable yield (FAO 2018); however, more fish stocks are being overfished.

Global trends in the state of the world’s marine fish stocks, 1974-2015.   Source:  FAO 2018.  CC-BY-NC-SA        

Fish and fish products provide an average of only ~34 calories per capita per day but the daily contribution varies widely by region based on availability of alternative protein sources and cultural preferences for fish.  Annual per capita consumption has more than tripled since 1961 in developing regions where four fish dominate our menu — salmon, sea bass, cod, and tuna (Greenberg 2011).   Many low-income regions of Latin America and Africa, where political instability and civil unrest have stymied economic development, still have very high food deficits.

Contribution of fish to animal protein supply (2013-2015).   Source:  FAO 2018.  CC-BY-NC-SA    

More people are consuming fish than ever before. The admonition to “think global and act local” should translate to eating locally harvested seafood and minimizing costs and unsustainable fishing practices. The Code of Conduct for Responsible Fisheries (FAO 1995) is a guiding framework for implementing sustainable fisheries and aquaculture operations. It sets out international principles and standards of behavior to ensure effective conservation, management, and development of both marine and freshwater living aquatic resources. It also accounts for the impact of fishing on ecosystems, the impact of ecosystems on fisheries, and the need to conserve biodiversity.    

Sustainability is a plastic word (Nikiforuk 2019). A fishery is not simply sustainable or not sustainable.  It’s more complicated and requires many choices.  Most practitioners accept three dimensions of sustainability: social, economic and ecological, but a deeper analysis requires consideration of six dimensions of sustainable development, specifically economic, social, ecological, institutional, ethical, and technological factors (Lam and Pitcher 2012; Aquado et al. 2016). For example, justice relates to equity or the fair distribution of benefits and harm, in terms of ecosystems and social justice. Many issues play into assessing sustainability.  Globally, we should be concerned with issues of seafood safety, bycatch, fish fraud, pollution from fish farms, post-harvest loss and waste, local governance, microplastics, lost and discarded fishing gear, overharvest of forage fish harvesting for fish meal, and many other social and ethical issues. As the trade flow diagrams show us, the source of our seafood is also complicated and most regions are importing much of their seafood. Your choice of fish to eat may depend on where and how it was harvested. 

Trade flows of fish and fish product by continent, share of total imports in value 2016 (%).  Source:  FAO 2018.  CC-BY-NC-SA        

Seafood certification, or ecolabeling, provided by third-parties, such as the Marine Stewardship Council and Seafood Watch, are the beginnings of evaluation of ethical and sustainble fisheries. Fishing practices changed dramatically in response to public outrage over harvest of dolphins in tuna purse-seining.  Fisheries that meet Marine Stewardship Criteria are highly selective for the target species, have limited access, well regulated, enforced, and often involve co-management between government, scientists, and fishers.  Seafood Watch develops fisheries and aquaculture standards to judge and communicate fish to “avoid” and “good” or “best” choices.  A novel aspect of this program rates whether fisheries support human trafficking, forced labor or child labor, as well as a new tool that collects data on carbon emissions (Monterey Bay Aquarium 2018).  These third-party certifications of sustainability have not yet delivered on the promise of price premiums, improved governance, or improved environmental conditions (Roheim et al. 2018). Challenges remain in the implementation of seafood sustainability due to potential for confusion about the overlapping goals of a growing range of sustainability initiatives (McClenachan et al. 2016).  

Three types of seafood sustainability initiatives and example goals of each (McClenachan et al. 2016).

One of the remaining issues of ecosystem justice remains to be solved.  With the expansion of aquaculture, the demand for fish meal has increased.   Small fishes, menhaden, anchovies, sardines, capelin, herring, and others are harvested and sent to reduction facilities that market and sell food to fish and other farms.   These fish, often labeled as forage fish, when overfished, no longer support seabirds and larger striped bass or bluefin tuna at higher trophic levels. 

What fish should I eat?  You can eat the fish you catch locally after you learn about local fish consumption advisories.  Take time to learn more about the fish you purchase to eat and how they were harvested.  Alaska Pollock Theragra chalcogramma had the highest catch of any fish in the world, followed by anchoveta, and Skipjack Tuna Katsuwonus pelamis.   Pollock is a “best choice” option according to Seafood Watch, but the Marine Stewardship Council has certified only the US fisheries for Alaska Pollock. McDonald's Filet-O-Fish contains Alaska Pollock in North America.   Skipjack Tuna is a “best choice” if harvested by trolling or pole-and-line fisheries, whereas the long line and purse seine fisheries is a “good choice” due to concerns of bycatch of dolphins. Tuna fisheries that use purse seines with FAD (fish attraction devices) should be avoided.   How do you know?   Look for the Marine Stewardship Council logo on any fish you purchase. 

I also started to compare the carbon foot prints of wild versus farmed seafood. The Seafood Carbon Emissions Tool was created by scientists at the Monterey Bay Aquarium Seafood Watch program and Dalhousie University. This tool also allows you to calculate the emissions associated with transporting the product to its final destination.   Most highly valued species such as shrimp, prawns, salmon, tunas, groundfish (e.g., cod, hakes, and haddocks), flatfish, seabass, and seabream are traded to the most prosperous markets, while less valued species are exported to developing countries. The US imports 98% of its Atlantic Salmon.  My favorite wild Alaskan Sockeye Salmon turns out to have a very high carbon cost associated with transport  

Since aquaculture provides over 50% of global seafood and the US imports the majority of its edible seafood, expect the supply of farmed seafood to continue to increase.  Hopefully, more of these products will be marketed with third party certification to assure responsible practices. Look for the logo for Best Aquaculture Practices Certification.  Watch for locally grown seafood from farms that use recirculating aquaculture technology and integrate aquaponics with fish production.  A land-based aquaponics farm, Superior Fresh, is expanding operations in Wisconsin on a 720-acre property producing fish and leafy green vegetables.  Superior Fresh is the first land-based Atlantic Salmon producer and the world’s largest aquaponics facility.  The goal is to producing seafood with a smaller environmental footprint than other options.  At a recent Wisconsin Aquaculture conference,  Greg Fischer, Manager of the Northern Aquaculture Demonstration Facility, predicted that Walleye “will be the next big food fish for aquaculture in the Midwest.”  This locally produced fish would reduce demand on wild stocks. 

References

Aguado, S.H., I.S. Segado, and T.J. Pitcher.  2016. Towards sustainable fisheries: A multi-criteria participatory approach to assessing indicators of sustainable fishing communities: A case study from Cartagena (Spain). Marine Policy 65:97-106.

Bakre, A.T. and thirteen coauthors. 2018.  Association between fish consumption and risk of dementia: a new study from China and a systematic literature review and meta-analysis.  Public Health Nutrition 21(10):1921-1932.

FAO. 1995. Code of Conduct for Responsible Fisheries. Rome.  Accessed 17 June, 2019 from http://www.fao.org/3/v9878e/v9878e00.htm

FAO. 2018. The State of World Fisheries and Aquaculture 2018 - Meeting the sustainable development goals. Food and Agriculture Organization of the United Nations, Rome, Italy.  227 pp.  Accessed 17 June, 2019 from http://www.fao.org/documents/card/en/c/I9540EN

Greenberg, P. 2011.  Four Fish: The Future of the Last Wild Food.    Penguin Books, 285 pp. 

Lam, M.E., and T.J. Pitcher. 2012.  The ethical dimensions of fisheries.  Current Opinion in Environmental Sustainability 4:364-373.

Marshall, S., and B. van der Meij. 2018.  Fish and omega-3 intake and health in older people.   Maturitas 115:117-118. 

McClenachan, L., S.T.M. Dissanayake, and X. Chen. 2016. Fair trade fish: consumer support for broader seafood sustainability.  Fish and Fisheries 17:825-838.

Monterey Bay Aquarium. 2018.  Monterey Bay Aquarium Seafood Watch Launches First-of-its-Kind Seafood Slavery Risk Tool.    Accessed 17 June 2019 from https://newsroom.montereybayaquarium.org/press/seafood-watch-launches-seafood-slavery-risk-tool

Nikiforuk, A. 2019.  Against ‘sustainability’ and other plastic words.  The Tyee  2 May. Accessed on 18 June at https://thetyee.ca/Opinion/2019/05/02/Sustainability-Plastic/

Roheim, C.A., S.R. Bush, F. Asche, J.N. Sanchirico, and H. Uchida. 2018. Evolution and the future of sustainable seafood market.  Nature Sustainability 1:392-398.