A few more serious items are worth a look too...
A look at Bluefin Tuna stocks of the North Atlantic and Blue Sharks in UK waters. These are at dire levels and are a drift amid decidedly mean seas. The UK has made the error of judgment in thinking that because the Chagos islands are in the far off Indian Ocean, there are no stakeholders that matter (matter to them, that is, or rank with their own importance). But it's flatly untrue. It is true that all oceans need our attention and protection... and all stakeholders are important.
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Collapse of Bluefin Tuna in the Western Atlantic
Carl Safina and Dane H. Klinger; 2008; Conservation Biology
"Everywhere they swim, blufin tuna are fished heavily. The European Commission (EC) recently moved to reduce catch quotas for the Eastern Atlantic and Mediterranean, but the quotas remain nearly double what the EC scientists recommended."
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Illegal Bluefin: Challenges to Counting Eastern Atlantic Bluefin Tuna
PEW fact sheet; October 2012
"The eastern Atlantic and Mediterranean stock of bluefin tuna (BFTE) has long been below a healthy population level. Although the International Commission for the Conservation of Atlantic Tunas (ICCAT), which manages bluefin in the Atlantic and Mediterranean, has significantly reduced quotas in recent years, several independent studies indicate that the actual catch of bluefin greatly exceeds annual quotas due to substantial illegal fishing."
"While there is debate about the extent of excess catch, ICCAT assumes no illegal fishing in recent years and hence bases its stock assessment and quotas only on reported catch. This seriously jeopardises the chance of BFTE recovering by 2022, the official ICCAT rebuilding deadline. A healthy future for bluefin depends on quotas and management decisions based on actual catch, which incorporates all sources of catch, including the most reliable estimates of illegal fishing."
"The 2012 study [’Trade-based Estimation of Bluefin Tuna Catches in the Eastern Atlantic and Mediterranean, 2005–2011’ by Antonius Gagern, Jeroen van den Bergh and Rashid Sumaila] estimates that total allowable quotas were exceeded by 62 percent between 2005 and 2011 and by 77 percent between 2008 and 2011, confirming previous reports of persistent and widespread illegal fishing in the BFTE fishery. This means that catch exceeded the quota by approximately 112,000 metric tons (mt) during the seven-year study period. Further, the gap between actual catch and the quotas is likely to be even higher due to black -market trade and several other factors not captured in official records."
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The IUCN Redlist of Threatened Species
Thunnus thynnus (Atlantic bluefin tuna)
Listed: Endangered (en)
Justification:
This Atlantic species has experienced declines in range and reported catch per unit effort (CPUE) since the 1960s. Although a number of uncertainties exist in the reported data, especially from the Mediterranean region, the best estimates from the most recent 2010 stock assessment indicate that there has been a global decline of between 29% and 51% based on summed spawning stock biomass (SSB) from both the Western and Eastern stocks over the past 21–39 years (three generations, based on a generation length of between seven and 13 years). Pre-exploitation longevity is not known for the Eastern Atlantic, but it is assumed that at one point that this species had a similar longer generation length across its global range. Therefore, this species is estimated to have declined at least 51% over the past three generation lengths (39 years) and is listed as Endangered under Criterion A2. In the Eastern Atlantic stock, current fishing mortality is far above maximum sustainable yield (MSY) and estimated SSB is far below MSY. The Western Atlantic stock has experienced severe declines in the past, is also below MSY, and has not recovered under current fishing regimes. Management of the eastern Atlantic stock is essential to the future of this species, as it represents the majority of this species global population.
This Atlantic species has experienced declines in range and reported catch per unit effort (CPUE) since the 1960s. Although a number of uncertainties exist in the reported data, especially from the Mediterranean region, the best estimates from the most recent 2010 stock assessment indicate that there has been a global decline of between 29% and 51% based on summed spawning stock biomass (SSB) from both the Western and Eastern stocks over the past 21–39 years (three generations, based on a generation length of between seven and 13 years). Pre-exploitation longevity is not known for the Eastern Atlantic, but it is assumed that at one point that this species had a similar longer generation length across its global range. Therefore, this species is estimated to have declined at least 51% over the past three generation lengths (39 years) and is listed as Endangered under Criterion A2. In the Eastern Atlantic stock, current fishing mortality is far above maximum sustainable yield (MSY) and estimated SSB is far below MSY. The Western Atlantic stock has experienced severe declines in the past, is also below MSY, and has not recovered under current fishing regimes. Management of the eastern Atlantic stock is essential to the future of this species, as it represents the majority of this species global population.
Eastern Atlantic and Mediterranean stock
In the Eastern Atlantic and Mediterranean stock, the reported catch from 2000–2004 averaged 32,000–35,000 tonnes/year, and the status of the stock is Over-Exploited (Majkowski 2007, ICCAT 2010). Currently this stock is fished at levels above FMSY, and estimated SSB is only about 35% of the biomass that is expected under a MSY (SRCS ICCAT 2010). The increase in mortality for large Bluefin Tuna is consistent with an apparent shift in targeting larger individuals destined for fattening and/or farming in the region. A quota system has been put in place to set levels for maximum sustainable yield (MSY) of 29,000 mt (STECF 2009), but current models put the MSY at 13,500 mt (SCRS ICCAT 2010). The current management structure has established TACs for the entire Mediterranean; however, recent genetic studies suggest multiple populations within the Mediterranean (Riccione et al. 2010). This is problematic because there is the potential for overfishing of segments of the Mediterranean population. In addition, information available has demonstrated that catches of Bluefin Tuna from the East Atlantic and Mediterranean were seriously under-reported between the mid-1990s through 2007. The lack of compliance with TAC and underreporting of the catch may have severely undermined the conservation of the stock (SRCS ICCAT 2010).
In the most recent stock assessment (SCRS ICCAT 2010), final estimated spawning biomass differs slightly between the two satisfactory model runs. The spawning biomass peaked at over 300,000 tonnes in the late 1950s and early 1970s, followed by a decline. Under run 13, the biomass continued to decline slightly to about 150,000 tonnes, while under run 15 biomass slightly increased during the late 2000s to about 2000,000 tonnes. Considering both runs, the analyses indicated that recent (2007–2009) SSB is about 57% of the highest estimated SSB levels (1957–1959).
Using endpoints of the base case (ICCAT 2010) there has been an estimated 45% decline in SSB over the past 39 years (1970–2009), and a 30% decline in SSB over the past 21 years (1988–2009) in the Eastern Atlantic stock.
In the Eastern Atlantic and Mediterranean stock, the reported catch from 2000–2004 averaged 32,000–35,000 tonnes/year, and the status of the stock is Over-Exploited (Majkowski 2007, ICCAT 2010). Currently this stock is fished at levels above FMSY, and estimated SSB is only about 35% of the biomass that is expected under a MSY (SRCS ICCAT 2010). The increase in mortality for large Bluefin Tuna is consistent with an apparent shift in targeting larger individuals destined for fattening and/or farming in the region. A quota system has been put in place to set levels for maximum sustainable yield (MSY) of 29,000 mt (STECF 2009), but current models put the MSY at 13,500 mt (SCRS ICCAT 2010). The current management structure has established TACs for the entire Mediterranean; however, recent genetic studies suggest multiple populations within the Mediterranean (Riccione et al. 2010). This is problematic because there is the potential for overfishing of segments of the Mediterranean population. In addition, information available has demonstrated that catches of Bluefin Tuna from the East Atlantic and Mediterranean were seriously under-reported between the mid-1990s through 2007. The lack of compliance with TAC and underreporting of the catch may have severely undermined the conservation of the stock (SRCS ICCAT 2010).
In the most recent stock assessment (SCRS ICCAT 2010), final estimated spawning biomass differs slightly between the two satisfactory model runs. The spawning biomass peaked at over 300,000 tonnes in the late 1950s and early 1970s, followed by a decline. Under run 13, the biomass continued to decline slightly to about 150,000 tonnes, while under run 15 biomass slightly increased during the late 2000s to about 2000,000 tonnes. Considering both runs, the analyses indicated that recent (2007–2009) SSB is about 57% of the highest estimated SSB levels (1957–1959).
Using endpoints of the base case (ICCAT 2010) there has been an estimated 45% decline in SSB over the past 39 years (1970–2009), and a 30% decline in SSB over the past 21 years (1988–2009) in the Eastern Atlantic stock.
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Appetite for shark fin soup 'causing decline of blue sharks in UK waters'
Study says blue shark population off UK coast is targeted by fisherman using 'wall of death' method, before being sent to Asia
Jonathan Watts; Guardian newspaper; March 2012
"The demand for shark fin soup in Asia is probably the major cause of the alarming decline of blue sharks off the British coast and much of the Atlantic, the authors of a new study claim this week."
"Scientists from the UK and Portugal have tracked the ocean predators to busy fishing grounds, where they believe they are being deliberately targeted by fishermen with "walls of death" from long-line fishing that can stretch as long as 100km."
"Blue sharks are thought to be the most frequently caught shark species, with population declines of up to 80% in some regions since the 1980s, the fish is now classified as "near-threatened" on the IUCN Red List."
"The new study published in PLoS One finds the strongest evidence yet that long-line fishing is to blame, prompting the authors to call for the establishment of protected areas."
PLoS One Article:
"Spatial Dynamics and Expanded Vertical Niche of Blue Sharks in Oceanographic Fronts Reveal Habitat Targets for Conservation" (go to article)
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The Future of Sharks: A Review of Action and Inaction
PEW TRAFFIC report; January 2011 (go to PEW PDF report)
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MPAs Work, But Only If... (go to full story at website)
March 16, 2013
Dr. Les Kaufman, Professor of Biology, Boston University
"Marine Protected Areas (MPAs) have become a rallying cry for marine conservation, and some see them as a panacea. They aren’t. Yes, they’re essential, but they aren’t sufficient. To work they must be part of a larger plan. The plan states what people seek from nature, and what measures are needed to ensure that nature can do its job in providing those things…forever. Since people are irrepressibly ambitious, enthusiastic, selfish, and often thoughtless, these measures generally equate to a system of restraint. People need guidance if they’re to avoid killing the goose laying all those golden eggs."
"The scope of the investigation was inspired by our donor/partner’s insistence that we not over-focus on marine reserves alone, but consider their context."
"The idea to begin scientific study of (Marine Managed Areas) MMAs was nothing new, but our shocker was that we had a serious interest in all aspects of MMA function, not only ecological, but also social, cultural, and economic. "
"Indeed, the best summary of what we learned in MMAS can be found in the traditional Fijian concept at the heart of MMA management throughout Oceania: the vanua, which represents the unity of land, sea and people as part of a common, interwoven and interdependent cosmos. Because the ecological and social bonds within the vanue are strong, whatever bad things you do in the vanua will come back to you and be visited upon everyone, but the effects of whatever good you do will also quickly be visible. Since smaller vanua are nested within larger ones, all the way up to the world as a whole, this lesson applies at all scales: What you do, comes back to you. "
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