Ken Okaniwa Throws Down - Shark Conservation Goes Crazy

Ken Okaniwa is a minister at the embassy of Japan in London and ­director of the Japan Information and Cultural Centre.

He also just penned "It is wrong to claim that the global shark population is declining," an op ed for the Guardian newspapers in London.

The electronic ink had not even dried on that article before howls of discontent and gnashing of teeth could be heard across the shark conservation spectrum.

It is wrong to claim that the global shark population is declining

Your article reports the assertion by conservation groups that "growing demand for shark fins, coupled with modern fishing methods, has caused a rapid decline in shark populations around the world" (A bloody business: Japanese town feeding appetite for shark fin soup, 12 February).

But there is no clear evidence for a global decline in shark stocks. Reduced catches can reflect various factors such as the intensity of fishing methods and variations in demand, in addition to the actual level of stocks.

In particular, the article refers to the blue shark as having been designated "near threatened" by the International Union for Conservation of Nature (IUCN). The fact is that an assessment of the blue shark population since 1971, published by the Western and Central Pacific Fisheries Commission (an organisation of 25 nations and regions including Japan, the US, Australia, New Zealand and the EU), demonstrated that stocks declined in the 1980s but later recovered to exceed the 1971 figure, and remained stable thereafter.

It is also notable that "near threatened" is the second least serious of the seven categories employed by the IUCN – which itself declares that the blue shark does not qualify for "threatened" status.

You report: "Several countries, including the US, have taken steps to conserve shark populations, but [the shark conservationist Mayumi Takeda] holds out little hope that Japan will follow suit." However, Japan is in fact one of the few countries to have prepared its own action plan based on the UN's International Plan of Action for the Conservation and Management of Sharks.

In addition, Japan has not only been providing data on shark stock assessment to the relevant international bodies but has also been encouraging the promotion of appropriate stock management methods.

Japan has been at the forefront of international efforts to protect threatened species. For example, at the International Commission for the Conservation of Atlantic Tunas (ICCAT) conference in 2009, Japan supported a proposal to ban the retention of thresher sharks in the Atlantic Ocean (the proposal would mean that the sharks have to be released immediately after capture). At the Indian Ocean Tuna Commission in 2010, Japan supported the EU bid to prohibit the retention of three types of thresher shark.

At the ICCAT in 2010, Japan proposed banning the retention of oceanic whitetip sharks, which was adopted. Japan also supported the EU proposals to ban the retention of hammerhead sharks and porbeagle sharks, though the latter was not adopted due to opposition from other countries.

Every country has its own dietary practices based on its particular historical and cultural background, and such matters should be discussed in a respectful way. Protecting sharks and other species requires a factual, science-based approach. This is how Japan will continue its efforts.

Impacts of climate change on tuna?

Interesting reading over at the SPC Ocean Fisheries Programme website this week on the effects of climate change on a regional fishery worth 4 billion.

Background

The tuna fishery in the western and central Pacific Ocean (WCPO) has undergone continuous expansion over the past 30 years, with the catch of skipjack, yellowfin, bigeye and albacore tunas reaching 2.4 million tonnes in 2007. The landed value of the catch in 2007 was approximately USD 4 billion, with considerable economic benefits accruing to Pacific Island Countries and Territories through direct participation in the fishery, employment, onshore processing, provision of fleet services and support, and foreign access licence fees.

With the increases in catch that have occurred, tuna resources in the WCPO are coming under increasing pressure. Skipjack tuna, which makes up 75% of the total catch and is responsible for nearly half the catch value, is currently in healthy condition, although exploitation rates continue to increase and may reach sustainable limits within the next decade. On the other hand, catches of yellowfin and bigeye tuna are estimated to be close to, or possibly exceed, their sustainable limits. Albacore tuna in the South Pacific is currently exploited within sustainable limits, but overfishing is believed to be occurring in the North Pacific.

In addition to the pressure from fisheries, the physical and biological oceanic environment is known to profoundly affect the distribution, abundance and catchability of tuna stocks. The effects of El Niño – Southern Oscillation (ENSO) variability in particular have been well documented, with El Niño events tending to result in eastwards displacement of tuna resources and fishing activity, higher catchability by purse seine fisheries through shoaling of the thermocline, positive effects on recruitment for skipjack, yellowfin and bigeye tunas and negative recruitment effects for albacore.

As models linking tuna stocks with biological and physical oceanography have been developed and enhanced over the past ten years, we are now able to see the effects of large-scale changes in ocean climate at the decadal and longer time scales. To date, these studies have mainly been hindcasts that reconstruct the historical responses of tuna stocks to such variability. However, recent advances in the modelling of atmospheric and oceanographic processes associated with climate change have opened the possibility of explicitly modelling the responses of tuna stocks to specific climate change scenarios.

More here.