One of the greatest threats to sharks (and many other marine animals for that matter), is mortality as bycatch in fishing gear that has been set to catch other commercially valuable species. Bycatch is responsible for the deaths of thousands of sharks every year, including many endangered species. Therefore, reducing bycatch in industrial fisheries has been highlighted as a serious conservation priority. Whilst some governments are making moves to reduce bycatch is various ways, one country has gone above and beyond ... Belize has completely banned gillnets within the country! But why is this such great news? Why are gillnets so bad? And how could their eradication help sharks?
What are Gillnets?
Gillnet fishing involves dropping a rectangular net into the water, so it is suspended vertically. Nets can either be suspended from several vessels (known as "drift gill nets") or can be attached to the ocean floor (known as a "set gillnet") (Ebert et al, 2021).
The mesh is designed to catch in the gills of fish, making it impossible for them to struggle free. Gillnets are used predominently for fishing salmon and swordfish, and different mesh sizes can be used to target different species (Ellis et al, 2017; Ebert et al, 2021).
Gillnets Kill Many Sharks Unnecessarily
By design, gillnets cause serious damage to the gills of fish. This makes them very effective for fishing commercially valuable species. However, animals that are caught as bycatch can also suffer serious injuries from the mesh. Therefore, gillnets are an extremely damaging method of fishing, with high bycatch mortality of not only sharks, but also dolphins, turtles and whales (Benavides, 2018; Ebert et al, 2021).
Gillnets can be immediately fatal to sharks caught as bycatch. This is known as "at-vessel mortality". For example, studies have shown that the overall mortality of Atlantic sharpnose sharks (Rhizoprionodon terraenovae), blacknose sharks (C. acronotus), blacktips, (C. limbatus) and bonnetheads (Sphyrna tiburo) caught in gillnets, are as high as 78·6% (Ellis et al, 2017).
Sharks can also die even if they are released from the gillnet and freed. This is because the production of stress hormones and the strain from injuries caused by gillnets can cause prolonged physiological strain. This is known as "post-release mortality". For instance, studies of spiny dogfish (Squalus acanthias) caught in gillnets suffer immediate mortality of only 17.5%, but overall mortality can shoot up to 55% over the next 48 hours (Ellis et al, 2017).
Gillnets can also cause major problems when they are lost as sea. These unsupervised nets, known as "ghost nets", continue to entangle and kill marine life (Benavides, 2018; TAT & YDCCF, 2021). To learn more, you can check out Ghosts in the Ocean.
Belize has Completely Banned the Use of Gillnets!
Located in the northeastern corner of Central America, the small country of Belize is rich with beautiful coastlines, magnificent coral reefs and unparalleled marine biodiversity. The people of Belize rely on their fisheries for subsistence and income, and their ocean resources are also very important for their tourism industry. There were great concerns that gillnets were causing too much bycatch and ghost fishing in Belize, and that this could lead to stock collapses or reduce the natural biodiversity. Both of which could be devastating to the Belizean people (Benavides, 2018; MFFESD, 2020; TAT & YDCCF, 2021).
So Belize took unprecedented action! Several years ago, a task force called the Coalition of Sustainable Fisheries was formed and in 2020 The Minister of Fisheries, Forestry, the Environment and Sustainable Development, Dr. Hon. Omar Figueroa, signed into Belizean law Statutory Instrument No. 158 of 2020 entitled 'Fisheries Resources Regulations 2020', aka the Gill Net Prohibition. This legislation stated that gillnets would be banned throughout the exclusive economic zone of Belize by January 2022 and that during the upcoming transition period, Belize would convert it's fisheries to less destructive methods (MFFESD, 2020).
The goal of this ban was to reduce wasteful bycatch in fisheries, in order to protect the natural biodiversity of Belize. It was also to ensure that their use of marine resources would be more sustainable and would not lead to stock collapses in the future. This was the first ever ban of this kind! (MFFESD, 2020).
“The ban on gill nets is a win for all Belizeans... [we] support policies & practices that increase abundance so that... Belize can always boast magnificent marine biodiversity.”
- Janelle Chanona, Vice President of Oceana
And Belize delivered! Not only did they achieve exactly what they set out to do, but they did it years ahead of schedule! In November, 2020, the government announced that their phase-out period had been completed and the use of destructive gillnets would now be banned throughout Belize (MFFESD, 2020).
Belize is Supporting their Fishers to Transition to Sustainable Methods
What is especially inspiring about Belize's legislation is that they have also incorporated a social policy into the conservation framework. Rather than just banning gillnets outright and criminalising the activities that career fishers had been practicing for years, the government of Belize offered a by-back to anyone who handed over gillnets. Fishers were given ongoing monthly payouts over the course of two years, to compensate them for the costs associated with buying new (less destructive) fishing gear. The government also supported fishers who chose to transition into a different form of employment instead (MFFESD, 2020; TAT & YDCCF, 2021).
"These measures will ensure that productive fisheries remain available for future generations of fishers & will provide security to all those whose livelihoods depend on a healthy marine ecosystem"
- The Coalition for Sustainable Fisheries, Belize
How Will the Gillnet Ban Help Sharks in Belize?
Belize's Caribbean waters boast remarkable biodiversity, including corals, fishes, invertebrates, sharks and rays. Critically, Belize also hosts some especially rare and endangered sharks, such as vulnerable nurse sharks (Ginglymostoma cirratum) and lemon sharks (Negaprion brevirostris), and endangered Caribbean reef sharks (Carcharhinus perezi) and whale sharks (Rhincodon typus).
Reducing the bycatch mortality of these animals could be vital to bolstering diminishing populations and creating a refuge area in Belize could help to bring some of these threatened species back from the brink of extinction.
With shark populations declining rapidly worldwide and more and more species being pushed to the brink of extinction, it is vital that we make changes as soon as possible! Belize made this change! They have taken a huge and radical step, and proven that protecting their biodiversity is of critical importance to their government. This sets a precedent for other countries. Hopefully, Belize will inspire other nations to follow suit and we will soon see sustainability improvements in other countries all around the world.
References
Benavides J (2018). The Negative Impacts of Gillnet Fishing on Marine Ecosystems: A Scientific Review. Universidad Andres Bello, Chile. Access online.
Ebert DA, Dando M& Fowler S (2021). Sharks of the World: A Complete Guide, Second Edition. Princeton University Press: UK. IBAN: 978-0-691-20599-1.
Ellis JR, Mccully Phillips SR & Poisson F (2017). Review of capture and post-release mortality of elasmobranchs. Journal of Fish Biology, 90:3, 653–722. Access online.
MFFESD (2020). Statutory Instrument No. 158 of 2020: Fisheries Resources Regulations 2020. The Coalition for Sustainable Fisheries and Oceana, Belize Ministry of Fisheries, Forestry, the Environment and Sustainable Development. Access online.
TAT & YDCCF (2021). Net loss or net gain? Gillnet use in Belizean waters. Turneffe Atoll Trust & Yellow Dog Community and Conservation Foundation Report. Access online.
By Sophie A. Maycock for SharkSpeak
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