The Decline of Tuna due to overfishing

Tuna are remarkable and impressive wild animals. The Atlantic bluefin can reach ten feet in length and weigh as much as 1500 pounds (more than a horse). Their specialized body shape, fins and scales enable some species of tuna to swim as fast as 43 miles per hour.
Tuna swim incredible distances as they migrate. Some tuna are born in the Gulf of Mexico, cross the entire Atlantic Ocean to feed off coast of Europe, and then swim all the way back to the Gulf to breed.
These extraordinary marine animals are also integral to the diet of millions and are one of the most commercially valuable fish. The majority of the market is made up of four species: skipjack, yellowfin, bigeye and albacore. As the methods of catching tuna have improved over the years, the conservation and management of tuna has not evolved as quickly. According to the United Nations Food and Agriculture Organization, most tuna stocks are fully exploited (meaning there is no room for fishery expansion) and some are already overexploited (there is a risk of stock collapse).

The once abundant Northern Bluefin Tuna (Thunnus Thynnus), which lives throughout the Atlantic Ocean and the Mediterranean Sea, is plunging in a free fall towards extinction. The Northern Bluefin Tuna population has a slow growth rate and also a late sexual maturity age. Bluefin larvae have a 1 in 40 million chance of reaching adulthood, an extremely low number for an endangered species. The Bluefin mature at around 8 years old, and are then able to reproduce; because of this, the Bluefin population is not growing at a fast enough rate in order to keep itself from becoming extinct. Greenpeace Red List lists the Bluefin as critically endangered, and its population has declines by 92% since the 1950’s.
The Atlantic Bluefin tuna has been the foundation of one of the world’s most lucrative commercial fisheries. Medium-sized and large individuals are heavily targeted by the Australian and Japanese raw fish market, where all tuna species, especially the Bluefin, are highly prized for sushi and sashimi. This economic importance has led to severe overfishing. In October 2009 Atlantic Bluefin stocks had declined dramatically over the past 40 years, by 72% in the eastern Atlantic, and 82% in the western Atlantic. At the current rate it is estimated that there will be less than a few thousand Bluefin tuna left by 2030.

Expert views:
According to information collected by the International Seafood Sustainability Foundation (ISSF), the Eastern Pacific stock of yellowfin is overfished and some overfishing is occurring in the Indian Ocean.The northern and southern Atlantic Ocean stocks of albacore are also overfished.The skipjack tuna, while quite resilient, could easily slip into a vulnerable state due to overfishing if improperly managed.
Bigeye tuna are prized in Asia for sashimi as well as frozen and fresh in other markets. As bluefin tuna populations shrink around the world, pressure on bigeye fisheries is increasing. According to information collected by the ISSF Scientific Advisory Committee, overfishing is occurring in Eastern and Western Pacific Oceans. Bluefin tuna populations have declined severely from overfishing and illegal fishing over the past few decades –not just Atlantic bluefin tuna, but also Pacific bluefin tuna and Southern bluefin tuna. Population declines have been largely driven by the demand for this fish in high end sushi markets.

What are WWF doing about it?
WWF focuses on transforming the global tuna fisheries market and improving the way tuna fisheries are managed and governed. Our approach is for tuna stocks to be managed as integral parts of the entire marine ecosystem. WWF works on seven tuna populations with the highest market value and therefore most vulnerable to overfishing: the Atlantic, Southern and Pacific bluefin, bigeye, yellowfin, albacore and skipjack tuna. We work with other organizations as well as the fishing, processing and retailing sector to transform tuna fishing into a sustainable business. Our goal is to achieve Marine Stewardship Council (MSC) certification for healthy and well-managed tuna populations.
Tuna Tagging
Since 2008, WWF has been tagging Atlantic bluefin tuna in the Mediterranean Sea to learn more about the species. The data collected so far has helped us learn more about their migratory behaviors and enabled us to advise fisheries managers on how best to protect the species. With more field tagging work, WWF and its partners can continue to fill the gaps on the bluefin’s biology and help give this emblematic fish a chance at survival for the long term.

Problems Occurring:

By-Catch: Since juvenile yellowfin school with adult skipjack, they are increasingly caught as bycatch by vessels that target skipjack. The removal of these juveniles before they have a chance to spawn could lead to fewer yellowfin in the long term. Skipjack tuna are abundant throughout their range and populations appear healthy. However, since juvenile yellowfin and bigeye tuna often school with adult skipjack, they are caught by purse seine vessels that target skipjack.

As we can see, this graph illustrates the rapid decline of Bluefin tuna from 600,000 metric tonnes to approximately 40,000 metric tonnes in under 40 years. This graph shows that Japan and Australia are the main culprits in the overfishing of southern Bluefin tuna. Comparing the graphs we can see that a large amount of tuna caught in the 1960’s-70’s meant an overall decrease in the total number of southern Bluefin tuna left.

Solution
The main solution to this problem, keeping both tuna numbers sustainable and allowing people to consume tuna at the same time is a Moldavian invented fishing method. This method Is called “Pole and line” and is a traditional fishing method, which is both socially and environmentally responsible. Requiring just one hook, one line and one fisherman, fish are caught one at a time.
In the Maldives, 47,720 tonnes of tuna were caught in 1985 compared to 152,582 tonnes caught in 2005. Although this may be a big increase, it’s small compared to that on the global scale. Pole and line fishing allows only mature tuna to be caught, meaning the juveniles are able to be left in the wild to mature and reproduce, once they have reproduced they are able to be caught and eaten. This means the stocks will continuously be replenished allowing for sustainable fishing. The benefits of pole and line fishing are that there is no by-catch, because the tuna are specifically targeted. This is done by selection of baits and hooks used.

Implications

 More jobs.
Pole and line fishing requires more fishermen per tonne of catch than any other fishing method. Local jobs for local people increases employment and the standard of living for many households across coastal communities.
 Higher incomes.
There is an increasing demand for sustainably and equitably caught tuna in Europe, the US, Japan and elsewhere. This has enabled coastal fishing communities to obtain a higher price for their pole and line caught tuna, shared between the many fishermen involved. The result is a more equitable distribution of resources.
 No overfishing.
The selective nature of the pole and line method makes it virtually impossible to deplete a fish stock since the fishing is literally done one-by-one. This enables tuna populations to maintain stable, natural reproductive rates and it ensures a sustainable supply to fishers. Endangered tuna species are therefore safe from extinction.
 No by-catch.
The pole and line method eliminates the risk of by-catch. In a lot of cases, lines are specially made for tuna and cannot injure or kill other species. Endangered and protected species such as sharks, whales, dolphins and turtles are not harmed by this fishing technique.
 Better serve sustainably-minded consumers.
There is presently a gap between the increasing demand for pole and line tuna and its supply. More pole and line tuna means more satisfied consumers, and the modest premium will continue to fall as more people support sustainable tuna.

There is however one problem with this solution to tuna fishing. A large portion of bait fish are used to attract the tuna, this has caused depletion in local bait fish stocks. Bait fish is prerequisite for the pole and line method of fishing. The fish used as bait are different species of small schooling fish found associated with coral reefs and lagoons. They are normally fished at night using lights and with stick-held dip nets. Coral reefs are not damaged during catching of live bait. Bait is kept alive on board the pole-and-line boats in bait holds in well-circulated water. Pole-and-line fisheries need 25,000 tonnes of baitfish to catch tuna each year. Although the method of extracting the live bait does not harm coral reefs, it doesn’t select only the mature fish, so often juveniles are caught amongst the adults and used as bait. This could potentially harm the local baitfish stocks as there are fewer juveniles that will grow and reproduce. Also other reef fish that prey on the baitfish may suffer due to a shortage of food.
However researchers suggest that improving management in bait fisheries through the introduction of management plans and stock assessments could resolve most of these issues and ensure that pole-and-line remains the most responsible and sustainable way to fish for tuna.

A simple alternative for the hunt for tuna, is to simply reduce the numbers caught. This can be done by having the International Union for Conservation of Nature declare varies species of tuna, such as the southern Bluefin tuna and Yellowfin tuna, as critically endangered and put sanctions and limitations on how much tuna can be caught and by whom. This will allow the tuna population to re-populate the seas at a more sustainable rate. However this will inevitably cause a shortage on the seafood stocks and cause fishermen to turn to a supplement species of fish, which could potentially endanger that type of fish. Tuna are a migratory species so it will be very hard to monitor where the tuna are, how many are being caught and who has the rights to their riches.
According to Greenpeace scientists, 40% of the world’s oceans need to be protected, this will be a far sufficient measure of what’s necessary to protect the tuna. While we need a massive expansion in the number and scale of ocean sanctuaries, they don’t need to be expensive. A study of how much it would cost to zone of protected areas across the oceans concluded it would be a cost of around $18-20 billion. “Many people believe that is a rather large sum of money, however it is estimated that by 2015 the global spend on luxury watches, handbags, shoes and jewellery will exceed 307 billion dollars –15 times the cost of the world's most essential asset – our oceans.” Salmon: An alternative to tuna

Atlantic salmon farming has long been controversial and its effect on the environment and on wild fisheries (particularly salmonid fisheries) is questioned by many individuals and organizations.

The major areas of concern are detailed in World Wildlife Fund reports:
• Local nutrient pollution into water systems, by waste feed/faeces.
• Local chemical pollution, by use of chemical treatments.
• Effect on wild fish, by escapees, through disease spread.
• Global environmental impact and issues of sustainability, since salmon production relies on supplies of fishmeal and fish oil for feed production, from industrial fisheries.

Another problem is the salmon’s location; they are best suited to cold climates. Norway, Canada, Chile and Scotland hold 95% of the Worlds salmon farms, so competition is fierce. Multinational corporations hold high market share’s in the lucrative business making it nearly impossible for new comers to enter the market, meaning they turn to easier fishing methods such as trawling for Bluefin tuna.

Also salmon farming does not yield the same cost : profit ratio as tuna. The potential of catching a fish matching the 496 lbs southern Bluefin tuna that sold for over $1.76 million attracts far more fishermen than the slow income of salmon farming. Tuna have, and will always be known for a great fishing fight and an achievement to land, so they will always have keen fishermen looking for “the thrill of the hunt”.
Reliability of Sources
In order to ensure that the data within my report was reliable and valid, I ensured that I followed the link to each reference on my chosen website and checked whether or not the information matched what the link said. This was successful as each link provided the same information as it suggested, proving that the information stated in my report is both valid and reliable. As well as this, I used a report written by a scientist rather than using yet another website, creating a wider range of sources of information. Not only this, due to the fact the report was written by a scientist, it could be someone who had direct statistics to the poaching numbers, conservation efforts and the increase/decrease in the number of tuna left. Their knowledge on this issue would also be much more accurate in comparison to a personal blog or an inexperienced person. Another way I had to ensure my data was both reliable and valid was through the actual source itself. I carefully selected my sources and information from websites that were reliable. For example, I used the WWF website as, as an official organisation widely known for working to help conserve a variety of species, they are clearly going to have precise and up-to-date information about the “save the tuna” programme.

Wikipedia

I ensured that I only used data that would be both reliable and accurate. In order to make sure that the data I took from Wikipedia was reliable, I followed the reference number to the reference link. I clicked on the link and read the data from the source as this would prove that the data I selected was accurate and hadn’t been falsely created. This proved to be effective for every piece of information I took from Wikipedia as within my referencing are several pages that Wikipedia used, and they show correct and reliable information. I can therefore say that when evaluating this source, it's accurate in terms of the data I used. Despite this, Wikipedia can be edited by anyone, and so other data from that page may not have been one hundred per cent reliable, suggesting that although this source may have been accurate for the information I took, other data about the black rhino on the page may not follow the same trend. The referencing may also link back to a website and match the information on that page, however the page it links to may not be directly accurate, proving that all sectioned data I used may not be entirely efficient.
One of the sources has come from the australian government department of environment. Making it extremely reliable due to them hiring their own biological scientists and conducting it themselves without the editing of others.

http://wwf.panda.org/what_we_do/footprint/smart_fishing/solutions/important_species_/tuna_2/

http://www.moyolaangling.com/content/?id=31&l1id=22&l2id=30

http://www.greenpeace.org/international/en/campaigns/oceans/marine-reserves/roadmap-to-recovery/

http://www.greenpeace.org.uk/blog/oceans/pole-and-line-fishing-catching-tuna-one-by-one-20121102

http://ipnlf.org/about-pole-and-line/

http://www.environment.gov.au/node/16509

http://ijumynesyla.comoj.com/world-record-southern-bluefin-tuna.php