As the world's demand for sharks continues to grow, shark populations are plummeting. The Asian market for shark fin is the key driver of shark fishing globally and is fuelling illegal fishing and high levels of legitimate shark fishing of questionable sustainability, according to a new report jointly published by the Australian Government and TRAFFIC, the wildlife trade monitoring network.

Sharks are particularly vulnerable to overfishing because they grow slowly, are late to mature and produce relatively few young. Currently more than a fifth of shark species are listed as threatened with extinction.

Glenn Sant, TRAFFIC's Global Marine Programme Leader and an author of the report, described the impact of illegal fishing as an unacceptable additional threat to the survival of populations of sharks.

"We simply don't know enough about the scale of global shark fishing practices to assess the true impact that legitimate fishing is having," he said. "Many so-called 'managed shark fisheries' are not constrained in any way to ensure they are sustainable, which opens up the threat of over-fishing."

The report was launched ahead of this week's United Nations Food and Agriculture Organization (FAO) meeting on sharks in Rome, which will discuss how to monitor shark fisheries and will consider the effect illegal fishing is having on shark numbers.

In 2000, FAO encouraged member countries to implement management of their shark populations, but seven years later fewer than 20% of members had introduced a plan to do so. Such national measures should include specific actions to tackle illegal shark fishing.

"The global lack of action towards conserving shark populations is inexcusable given the knowledge we have about the impacts of fishing on these animals," Sant emphasized.

"While shark numbers plummet, the major shark catching countries have shown little uptake of recommendations on monitoring or management, so we welcome the efforts that FAO is making this week in Rome."

Only six of the top 20 shark-catching countries or territories have implemented plans of action to manage sharks.

TRAFFIC believes it is imperative to create frameworks to support rapid national action to improve the management of sharks. Countries with developed management systems need to implement measures to address the impacts they are having on sharks. In addition, assistance should be provided to countries with less developed systems to establish monitoring and management of shark fisheries.