Monday, 29 August 2011

Alex Rogers & the State of the Ocean

Dr. Alex Rogers is Professor of Conservation Biology at the University of Oxford and the Scientific Director at the International Programme on the State of the Ocean (IPSO).  This quick video was shot at an important meeting at the United Nations in June.  

Wednesday, 24 August 2011

Save Deep-sea Sharks: Squalene and Trade Restrictions

Greenland shark, typically ranging at 200-600m depth (Credit: Discovery Channel)

The world has seen important progress made in the fight to protect widely endangered shark populations over the past few years.  In particular, we’ve seen movement in the United States and its territories, in Latin American countries such as Honduras and Chile, and in small island developing States such Palau, the Maldives, and the Bahamas.

In spite of this progress, no specific protections have been extended to deep-sea sharks, which are caught in national and international waters around the world.    

This is why the DSCC welcomes a new effort by the Pew Environment Group, a member of the DSCC since its beginning in 2004.  Pew is calling for trade restrictions to protect endangered deep-sea sharks. 

The ‘Beauty’ of Shark Liver Oil

While coastal and epipelagic species of sharks are sought after for their fins—usually to make shark-fin soup—deep-sea sharks are typically caught for their livers, which may constitute up to 30% of their body weight.

Shark liver oil can be used as an ingredient in cosmetics, and some purport that shark liver oil –marketed under the name ‘Squalene’ – can bestow health benefits.  It is estimated that it takes 3,000 sharks to make just 1 ton of Squalene, and the global market for Squalene is between 1,000-2,000 tons per year.  That means a demand of as many as 6 million deep-sea sharks a year!
Squalene sourced from deep-sea sharks is frequently advertised as a health supplement.  (Credit: Guangzhou By-health Bioengineering Co., Ltd.)
To a lesser extent, shark liver oil is used as a machine lubricant and in some pharmaceutical products. 

Victims of Biology

Deep-sea sharks are at high risk of over-exploitation because they grow very slowly and don’t reach sexual maturity until relatively late in life (anywhere from 12 to 35 years of age!).  Deep-sea shark populations simply can’t recover fast enough from current fishing activities. 

For example, in the Northeast Atlantic, where we have some of the best data on deep-sea shark fisheries, the IUCN classifies the gulper shark (Centrophorus granulosus) as ‘Critically Endangered’ and the leafscale gulper shark (Centrophorus squamosus) and Portuguese dogfish (Centroscymnus coelolepis) as ‘Endangered’.  Four other deep-sea shark species in the Northeast Atlantic are categorized as ‘Vulnerable’. 

In recent years, the European Union has moved to phase out targeted deep-sea shark fisheries, and bycatch will soon no longer be permitted to be sold.  While this is a positive step, it is an easy policy change when their catches have declined so steeply in past years.

Trade Protections

One way to greatly reduce the fishing of deep-sea sharks is to restrict international trade in their by-products to levels that have been deemed sustainable.  The Pew Environment Group has taken the first important step in raising awarenesss of the impacts of international trade with its recent submission to the 25th meeting of the Animals Committee of the Convention on the International Trade in Endangered Species (CITES).

As the submission explains, a number of deep-sea shark species meet the criteria for being listed on Appendix-II of CITES.  These species are the Portuguese shark (Centroscymnus coelolepis), the Leafscale gulper shark (Centrophorus squamosus), and all other species in the Centrophorus genus.  An Appendix-II listing would require that trade in these species by-products be regulated so that trade is ‘non-detrimental to the survival of the species in the wild’.

A Step Forward

The CITES Animals Committee met July 18-22, 2011, providing the conservation community with the opportunity to engage with government representatives, the United Nations Food and Agriculture Organization (FAO), and other intergovernmental organizations.  Some government representatives and observers thought Pew’s submission raised valid concerns about the state of fisheries for deep-sea sharks.

After much discussion in the working group, the Animals Committee invited all member countries to submit a list of shark species that they believe require additional protections.  These species will then be considered by a working group on sharks at the next Animals Committee meeting in March 2012. 

This request for more species-specific information is important.  Such an open request for species suggestions is uncommon at CITES, and the submissions mean that the species will have the opportunity to be discussed in the future.  All in all, it is a first step in protecting deep-sea sharks before our fishing activities push them over the brink to extinction.

(A summary report of the Animals Committee meeting can be found here.) 

  • C. Gibson, S.V. Valenti, S.V. Fordham, and S.L. Fowler. The conservation status of Northeast Atlantic chondrichthyans: report of the IUCN shark specialist group Northeast Atlantic red list workshop. IUCN Species Survival Commission Shark Specialist Group. Newbury, UK, 2008.
  • Oceana. From Head to Tail: How European Nations Commercialise Shark Products. 2008. Available at:
  • MRAG. Deep Sea Market Study.  Report Prepared for the Pew Environment Group.  April 2011.

Monday, 8 August 2011

A New Era in Deep-sea Exploration

A concept drawing of Virgin Oceanic's new submersible.  Credit: Virgin Oceanic.

We are now at the cusp of a new era in deep-sea exploration.  Over the past year, three commercial submersible operations have launched with the goal of exploring the deepest parts of the ocean.  Part of this is due to advances in materials, and part is due to the interests of wealthy individuals.

As the New York Times writes, these ventures are backed by several big names:

The billionaires and millionaires include Mr. Cameron, the airline mogul Richard Branson and the Internet guru Eric E. Schmidt. Each is building, planning to build or financing the construction of mini-submarines meant to transport them, their friends and scientists into the depths. Entrepreneurs talk of taking tourists down as well.

These ventures will have clear benefits for the scientific community.  Cameron has shared that he is looking to form long-term relationships with oceanic institutions, in addition to the fact that he was recently made a National Geographic Explorer-in-Residence.  And Schmidt is solely focused on advancing science.   

Wednesday, 3 August 2011

Man and the Last Great Wilderness: Human Impact on the Deep Sea

Synergies among anthropogenic impacts on deep-sea habitats. The lines link impacts that, when found together, have a synergistic effect on habitats or faunal communities. The lines are color coded showing the direction of the synergy. LLRW=low-level radioactive waste; CFCs=chlorofluorocarbons; PAHs= polycyclic aromatic hydrocarbons.Credit: Ramirez-Llodra E, et al. PLoS ONE.DOI:10.1371/journal.pone.0022588 (Image amplify’d from Deep Blue Home)

A new study is out on the human impact on the deep sea.  Not only is this an important contribution, but it is also getting great pick up on the web.  (The basics are covered here on our webpage.)

The two best posts so far can be found at Nature and at Julia Whitty’s Deep Blue Home.  Nature highlights the finding that conservation lags far behind exploitation activities and the science.  Quoting the report:
"One of the main problems that continue to cause concern is that the fastest movers in the deep sea are those who wish to use it as a service provider. Lagging behind somewhat are the scientists, managers and legislators."
Meanwhile, Julia Whitty brings the story home with her seemingly unlimited collection of amazing ocean photos.  Check them out here.

Tuesday, 2 August 2011

The Ecosystem Impacts of Deep-sea Fishing

In many fisheries, you hear a lot of talk about the ecosystem impacts of fishing.  This includes the collateral damage of bycatch.  And it includes ‘trophic cascades’, where by fishing down one species, there is a cascading impact on the food chain.  Perhaps the most famous example of this is the impact of the collapse of Northwest Atlantic cod stocks.

That means the true costs of fishing are far greater than the costs of operations and marketing, and that it is very likely that the consuming public is being ‘over served’ on certain fish species.   

The deep sea is full of delicate life, such as this assemblage of anemones, brittle stars, and corals. Credit: Sönke Johnsen.  
In the case of deep-sea fisheries, especially those using bottom trawl gears, we find significant ecosystem impacts.  Consider this:

Bottom trawl gear destroys important habitat that sustain the ecosystem. The destructive gear used to catch an estimated 80% of deep-sea species on the high seas leaves coral gardens and sponge beds devastated.  These habitats provide many important ecosystem services to other species, including those targeted by deep-sea fishing operations.  For instance, off the coast of British Columbia, a study found that trawled areas had 13 times less coral and attracted few rockfish, an important target species.

Deep-sea fishing frequently yields large amounts of bycatchFor instance, one study found that between 1995 and 1997, an average of 48.5 percent of French deepwater fish catches in the Northeast Atlantic were discarded as undesirable.  More recently, ICES reported that bycatch accounts for about 30 percent of catch in weight and 50 percent in number for French fleets targeting roundnose grenadier in the Northeast Atlantic. 

It is also clear that the bycatch of deep-sea species is far more ecologically damaging than the bycatch of shallow water species.  Most deep-sea fish cannot survive the changes in pressure as they are brought up from the depths, so fish are discarded dead.  And deep-sea fish are adapted to conditions of low turbulence and their skin is not covered by mucus, so there is also high mortality among fish that escape through trawl meshes.

And lastly, the impacts of deep-sea fishing cascade down the food chain and into the deeper oceanWhen one species’ population collapses, studies suggest that others may fall with them.  In the case of hagfish, data shows that when commercial fishers went after some hagfish populations, the stock of other commercial species plummeted.  It is known that by consuming the dead and decaying carcasses that have fallen to the benthic zone, hagfishes create a rich environment for other species including codfish, haddock, and flounder.

A recent study found that deep-sea trawling off the coast of Ireland is likely to have caused a 70 percent decline in the abundance of deep-sea species up to a depth of 1,500 meters since 1977.  Just as troubling, declines in fish abundance were observed as far down as 2,500 meters, far below the reach of the trawl nets.

Ultimately, we find that the true costs of deep-sea fishing are far greater than what appear on company balance sheets.  It is time we protect the deep-sea and see that short-term commercial interests do not trump those of the rest of the world.

  •  V. Allain, A. Biseau, and B. Kergoat. 2003. Preliminary estimates of French deepwater fishery discards in the Northeast Atlantic Ocean. Fisheries Research 60(1) : 185-192.
  •  ICES. 2010. Widely Distributed and Migratory Stocks. Report of the ICES Advisory Committee, Book 9. Available here.
  • Matthew Gianni (2004). High Seas Bottom Trawl Fisheries and their Impacts on the Biodiversity of Vulnerable Deep-Sea Ecosystems: Options for International Action. Executive Summary. IUCN, Gland, Switzerland.  Available here.
  • Alexis Bensch, Matthew Gianni, Dominique Gréboval, Jessica Sanders, and Antonia Hjort. 2008. Worldwide review of bottom fisheries in the high seas. Technical Paper No. 522. Food and Agriculture Organization. Rome
  • P.A. Large, C. Hammer, O.A. Bergstad, J.D.M. Gordon, P. Lorance. 2003. Deep-water fisheries of the Northeast Atlantic: II assessment and management approaches. Journal of Northwest Atlantic Fisheries Science. Vol. 31: 151-163.
  •  C.M. Roberts. 2002. Deep impact: the rising toll of fishing in the deep sea. Trends in Ecology and Evolution, 17(5), 242-245.
  • D. M. Bailey, M.A. Collins, J.D.M. Gordon, A.F. Zuur, and I.G. Priede. 2009. Long-term changes in deep-water fish populations in the northeast Atlantic: a deeper reaching effect of fisheries? Proceeding of the Royal Society Biological Sciences, 275: 1965-1969.
  • Landon Knapp, Michael M. Mincarone, Heather Harwell, Beth Polidoro, Jonnell Sanciangco, and Kent Carpenter (2011). “Conservation status of the world’s hagfish species and the loss of phylogenetic diversity and ecosystem function.” Aquatic Conservation: Marine And Freshwater Ecosystems. DOI: 10.1002/aqc.1202