Anchovy fishery threatens magellanic penguins
The recently expanded anchovy fishery off the coast of Argentina could seriously endanger marine life in Patagonia in the long term, scientists from the USA and Argentina warn. A collapse of the ecosystem would ultimately also have a significant impact on tourism - a main source of income for the remote region.
In 2003, Argentina's Federal Fisheries Council approved Chubut Province's application to allow a limited trial anchovy fishery in coastal waters south of the 41st parallel. The aim was to find an alternative for the hake stocks that had already collapsed due to overfishing. In the following two years, Argentine fishermen caught more than 30,000 tons of anchovies for the first time in thirty years.
Elizabeth Skewgar of the University of Washington in Seattle and her colleagues criticize that the impact of fishing on marine life has not been taken into account. The area is close to the Valdés Peninsula, which has been declared a UNESCO World Heritage Site because of the resident marine mammals such as elephant seals, sea lions and right whales. Not far away is Punta Tombo with the world's largest colony of Magellanic penguins.
The currently fished Argentine anchovy (Engraulis anchoita), which is processed into fishmeal for aquaculture, represents an important link in the marine ecosystem according to the scientists: It regulates the plankton and in turn serves as prey for numerous marine animals. Magellanic penguins (Spheniscus magellanicus) live mainly on them, but also feed on the Patagonian hake (Merluccius hubbsi), which in turn eats anchovies and whose stocks have since declined sharply. How the individual parts of the food web are linked is still far from being properly understood, the researchers warn.
The scientists demand that the ecological and economic consequences of the anchovy fishery must be examined in detail. In 2005, for example, the province of Chubut received 125 million euros directly and 230 million euros indirectly through ecotourism, which is largely based on the biodiversity of the coast – a source of income that is acutely threatened when the anchovy stocks collapse.
If the fishery is already established, however, it would be difficult to politically enforce a reduction in catch quotas, argue Skewgar and Co. In 1999, for example, the Argentine government had to contend with strong opposition when it tried to reduce fishing quotas for the overexploited hake. (aj)