By Mark Kinver
Science and nature reporter, BBC News
A senior marine scientist has welcomed European Commission proposals for a shark conservation action plan.
The rising demand for shark products is threatening many species
Sarah Fowler, co-chairwoman of the IUCN shark specialist group, described the plan as "great news" for the creatures.
About 32% of shark species that are found in the north-eastern Atlantic are said to be "threatened with extinction".
The main threats to the slow-growing creatures were overfishing and being caught in nets as bycatch, she added.
She told BBC News that species such as the angel shark and common skate were among the species to be assessed as "critically endangered" by the IUCN Red List, which was last updated in 2007.
"The structure of the Commission's proposal is great; it makes me very optimistic," Ms Fowler said.
The Community Action Plan for Sharks, which will be presented to the European Parliament and member nations at the end of the year, is designed to reverse the decline of sharks in European waters.
It stated that a number of factors were responsible for this trend, including improvements in fishing technology, processing and consumer marketing, expanding human populations and declines in other fish stocks.
"All of which have made sharks a more valuable fisheries resource. Thus, shark fisheries have experienced rapid growth since the mid-1980s due to an increased demand for shark products," it said.
It added that demand was particularly high for shark fins in Asian markets, but its meat, skin and cartilage were also sought.
Between 1984 and 2004, world catches of sharks grew from 600,000 to more than 810,000 tonnes.
Also, thousands of sharks have been accidentally caught every year on fisheries' tuna longlines since their introduction in the 1960s.
The UN Food and Agriculture Organization brought forward an international plan of action for the conservation and management of sharks, but the EU did not adopt all of the voluntary measures.
The European Commission said that it did not feel the measures adopted by member states were sufficient to rebuild the depleted populations of sharks.
Mrs Fowler told a scientific meeting at the Zoological Society of London that the key to the success of the EU action plan would be the effective management of the waters, which would be underpinned by improved data.
She explained that this would include improved investment in catch, biological and trade data. It would also be necessary, she added, to be able to assess threats to populations, and identify and protect critical habitats.
The Shark Alliance, a coalition of conservation, fishing and scientific organisations, says that up to 73 million sharks are killed each year for the global fin trade.
The fins, exported to Asia to be made into shark fin soup, are among the most expensive sea food products, reaching up to 500 euros (£380) per kilogramme.
The practice of "finning", which involves cutting the fin off a shark and throwing the rest of the body back into the water to drown, was outlawed by European nations but is still permitted under licence.
The EU, primarily Spain, is a major exporter of shark fins to China and Hong Kong.
The IUCN is set to publish the first global Shark Red List - the most comprehensive taxonomic assessment to date - in October 2008.