Subject: Reconciling fisheries with stopping biodiversity loss

Authors: N. K. Dulvy, R. Hanel, J. G. Hiddink, P. Licandro, P. Lorance, B. R. MacKenzie, G. Menezes, U. Piatkowski, and R. ter Hofstede.

Marfish, a subproject of the EU Network of Excellence MarBEF, has prepared the following statement for the e-conference topic “Reconciling Fisheries with Stopping Biodiversity Loss”.

Threats to marine biodiversity
The ocean contains most of the phyletic diversity of life on earth. The main factor that has threatened marine biodiversity globally hitherto is fishing (Dulvy et al. 2003, Garcia et al. 2006). For example, worldwide over 40 local populations of marine fishes have gone extinct as a result of overexploitation (Dulvy et al. 2003). Fishing also has impacts on non-target species via their capture and it damages benthic habitats and communities (Kaiser et al. 2006). Removal of target fish species can indirectly affect abundance and diversity of organisms at lower trophic levels leading to changes in ecosystem functioning (Frank et al. 2005, Myers et al. 2007, Daskalov et al. 2007), and can impact the availability of prey for fish and seabird predators (Frederiksen et al. 2006). Disturbance by fishing increases vulnerability of populations and ecosystems to other stresses such as climate variability (Brander 2005) and invasive species (e.g. Shiganova & Bulgakova 2000) which can subsequently affect marine biodiversity.

What the EU and its citizens can do to promote conservation and recovery of fish biodiversity
The EU has made substantial progress in recent decades in developing the legislative framework for conservation and recovery of fish biodiversity: the European Parliament and Council have passed several regulations designed to protect fish stocks, conserve fish biodiversity, and move towards an ecosystem-based approach to fisheries management. The EU is also committed to many international fishery and biodiversity agreements (EU 2005). Despite the legislative progress, 22-53% of the exploited fish populations in north-east Atlantic waters have fallen below safe biological limits (EEA 2005) and some of the populations have not recovered, partly because of high by-catches (e. g., North Sea cod).

These observations suggest that some of the well-intentioned legislation does not work in practice, or is not being fully implemented and enforced by political and national authorities. Options to complement these actions should include:

-reductions in fishing mortality on overexploited stocks (aiming both to reduce over-exploitation and minimise the impact of impending climate change);

- Broadening the range of conservation measures based on improved scientific knowledge and process understanding (e. g., more and larger MPAs where and when appropriate, restoration of habitats, encourage the use of less habitat-damaging fishing practices);

-Ensuring effective, prompt implementation and enforcement of fishing regulations and effort control. This action alone would probably have greatest positive impact on marine biodiversity.

- Move towards fishery management framework that discourages over-capacity and wasteful fishing methods, and that encourages energy efficient and responsible fishing methods; in particular the advantages of individual quotas should be considered

Fish consumers in the EU have increasing opportunity to choose fish from sustainable sources. By doing so, they have the power to drive market demand and influence businesses and politicians, which in turn supports moves toward more widespread sustainability. Identifying such fish at the local fish shop would become easier if a sustainable fishery certification mechanism were developed and became available in all European countries.

The objective of the e-conference session is to discuss relevance of the proposed actions that policymakers, stakeholders and consumers can take to reduce the likelihood of losing marine biodiversity and guarantee that marine ecosystems can continue to provide the goods and services that support human well-being.


References:
Brander, K.M. 2005. Cod recruitment is strongly affected by climate when stock biomass is low. ICES Journal of Marine Science 62: 339-343.
Daskalov, G.M., Grishin, A.N., Rodionov, S., Mihneva, V. 2007. Trophic cascades triggered by overfishing reveal possible mechanisms of ecosystem regime shifts. Proceedings of the National Academy of Sciences of the United States of America 104: 10518-10523.
Dulvy, N.K., Sadovy, Y., Reynolds, J.D. 2003. Extinction vulnerability in marine populations. Fish and Fisheries 4 (1): 25-64.
EEA. 2005. Is the use of commercial fish stocks sustainable? Report No. http://themes.eea.europa.eu/IMS/IMS/ISpecs/ISpecification20041007132227/IAssessment1116498234748/view_content (viewed Oct. 26, 2006).
EU. 2005. EU fisheries legislation in force. http://ec.europa.eu/fisheries/legislation_en.htm.
Frank, K.T., Petrie, B., Choi, J.S., Leggett W.C. 2005. Trophic cascades in a formerly cod-dominated ecosystem. Science 308, 1621-1623.
Frederiksen, M., Edwards, M., Richardson, A.J., Halliday, N.C., Wanless, S. 2006.
From plankton to top predators: bottom-up control of a marine food web across four trophic levels. Journal of Animal Ecology 75: 1259-1268.
Garcia, S. et al. 2005. Workshop 10, Paris Conference: Biodiversity, Science and Governance, Jan. 24-28, 2005 (report of the debates and proposed priority actions) (Ministry of foreign affairs, Government of France, Paris, 2006).
Kaiser, M.J., Clarke, K.R., Hinz, H., Austen, M.C.V., Somerfield, P.J., Karakassis, I. 2006. Global analysis of response and recovery of benthic biota to fishing. Marine Ecology-Progress Series 311: 1-14.
Myers, R.A., Baum, J.K., Shepherd, T.D., Powers, S.P., Peterson, C.H. 2007. Cascading effects of the loss of apex predatory sharks from a coastal ocean. Science 315: 1846-1850.
Shiganova, T.A., Bulgakova, Y.V. 2000. Effects of gelatinous plankton on Black Sea and Sea of Azov fish and their food resources. ICES Journal of Marine Science 57: 641-648.



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