European research focus on sharks and rays

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

The third thematic issue of Marine Biology Research is devoted to recent investigations on the taxonomy, biology, and ecology of sharks and rays by European scientists. Although popular, the chondrichthyan fishes (sharks, skates, rays and chimaeras) have been little studied, but in recent decades, scientists have shown a growing interest in this group of fishes. There are several reasons for this trend: (1) the chondrichthyans have a long evolutionary story starting in the Devonian era, i.e. about 450 million years ago, so their study is important to understand the basal evolutionary patterns of the vertebrates; (2) many sharks and rays have traditionally been exploited, but the huge increase of fishing efforts all around the world has caused serious concerns about the conservation of their populations that are drastically declining; (3) it has been demonstrated recently that sharks play an important ecological function in the regulation of the marine ecosystems, indeed as apex predators they regulate the populations of prey on which they feed; and (4) some sharks and rays are used as biological models to study a number of physiological questions (e.g. osmoregulation). Although the chondrichthyan fishes have a structural homogeneity, they are very diverse regarding shape, colour pattern, size, reproductive and feeding strategies, habitat and behaviour.

In Europe, the European Elasmobranch Association (EEA) was set up in 1996 to promote research on the biology of sharks and rays, and to advocate for sustainable management of their fisheries and the conservation of threatened species and their habitats. Annually, EEA organizes a scientific meeting to make known the actual state of the art shark research and conservation. In 2007, the 11th EEA meeting took place in Brest (France) and was locally organized by the ‘Association pour la Protection et la Conservation des Sélaciens’ (APECS). It gathered together 100 specialists who presented 23 oral communications and 33 posters covering the following themes: palaeontology, taxonomy and biogeography, biology, ethology, fisheries and conservation of elasmobranch fishes. The present issue includes some papers resulting from communications presented at this 11th EEA meeting, along with other papers submitted separately, but dealing with the same topics.

Since 5th February 2009, the European Community has adopted a community Action Plan for the conservation of sharks, following, with some delay, the recommendation of the FAO International Action Plan for the conservation and the management of shark populations (‘IPOA-Sharks’, FAO 1999). While waiting for the implementation of this community plan, some conservation and management measures have already been taken: a number of shark and ray species are regulated by quotas (TAC: total allowable catch) in European fisheries, and some threatened species should be released at sea. However, few sharks and rays have been listed in the international convention appendices (e.g. CITES, CMS, etc.). Several proposals are currently in preparation or under review to establish measures towards increasing their numbers in the forthcoming months or years.

Recently, the Shark Specialist Group of IUCN (http://www.iucnssg.org/) assessed the status of the shark and ray populations of the North-East Atlantic (in 2008) and of the Mediterranean Sea (in 2007), and estimated, in its Red List of threatened species, that 12 are critically endangered (CR), 12 endangered (EN) and 18 vulnerable (VU) out of the 92 evaluated species of European waters.

A juvenile round skate, Rajella fyllae (Lütken, 1887), photographed shortly after collection by bottom trawl in the Barents Sea, September 2006, during an ecosystem survey with RV Johan Hjort (Institute of Marine Research, www.imr.no). The fish (145 mm TL) has been deposited at the fish reference collection of the Institute of Marine Research, Bergen (HIFIRE F15-4). Photographer: David Shale (www.deepseaimages.co.uk).

As a result, there is still a lot of work to carry out to understand this group of fishes, and research projects are urgently needed for a conservation perspective.

The present thematic issue includes four original articles resulting from communications presented at the 2007 EEA meeting in Brest, four original articles submitted independently during the same period, and two book reviews. The topics of the research articles deal with species’ regional and depth distributions, new records for larger areas, population ecology as well as shark behaviour and reproductive biology. Species concerned are mainly from the North-Eastern Atlantic and the Mediterranean Sea (e.g. the Atlantic sawtail catshark Galeus atlanticus (Vaillant, 1888), the lantern shark Etmopterus spinax (Linnaeus, 1758), the small-spotted dogfish Scyliorhinus canicula Linnaeus, (1758) and the Norwegian skate Dipturus nidarosiensis (Storm, 1881)), but also from the Bahamas (the lemon shark Negaprion brevirostris (Poey, 1868)), South Africa (the great white shark Carcharodon carcharias (Linnaeus, 1758)) and the Maldives Islands (the manta rays Manta alfredi (Krefft, 1868) and M. birostris (Walbaum, 1792)). These papers show that nowadays a growing number of scientists are interested in chondrichthyan fishes and their taxonomy, biology, ecology, ethology, and conservation, both in Europe and worldwide. As a result, this thematic issue contributes to increasing our knowledge on these fascinating fishes. They deserve it!

Finally, some announcements regarding changes on our editorial board. We thank Kenneth Halanych, who left us, for his collaboration as a subject editor since the launch of Marine Biology Research. Danny Eibye-Jacobsen has joined us as a subject editor for polychaetes. Welcome!

Notes

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark