UN Draws Battle Lines Against Marine Invaders
Date: 11-Feb-04
Country: UK
Author: Stefano Ambrogi
"Invasive alien species," as the United Nations calls tiny aquatic organisms that scientists say can wreak havoc with native ecosystems, have an unlikely form of travel: piggybacking to different parts of the world in ships' ballast water.
To counter the growing problem the U.N.'s International Maritime Organization (IMO), the world's top maritime body, began a week-long meeting in London this week to finalize tough laws aimed at halting their spread.
"The introduction of harmful aquatic organisms and pathogens to new environments has been identified as one of the four greatest threats to the world's oceans," IMO Secretary-General Efthimios Mitropoulos said at the opening of the meeting.
"Proper control and management of ships' ballast water is therefore a major environmental challenge for IMO and the global shipping industry."
Mitropoulos said the global economic impact of invasive species had still not been properly quantified, but he said estimates put the annual cost at tens of billions of dollars.
"Unlike oil spills and other marine pollution caused by shipping, exotic organisms and marine species cannot be cleaned up or absorbed into the oceans," Mitropoulos said.
Ballast provides ships with balance and stability, but also gives a free ride for up to 100 different organisms per cubic meter (35 cubic feet), until they are flushed into another ecosystem thousands of miles away.
The IMO said some of the world's most unwanted "alien invaders" include water fleas introduced into the Baltic Sea from the Caspian where populations have exploded, clogging shipping nets and trawls.
Highly adaptive blooms of toxic red-brown algae have killed large quantities of marine life and contaminated shellfish.
Zebra mussels from eastern Europe have caused close to a billion dollars worth of damage to water pipes and underwater structures in North America.
The IMO also says there is evidence linking ballast water to the introduction of specific strains of cholera (Vibrio Cholerae) to the Gulf of Mexico and parts of South America.
The World Wildlife Fund has said the world faces a marine species disaster if no action is taken. WWF calls for mandatory rules governing the treatment of the estimated 10 billion tonnes of ballast water carried round the globe every year.
The WWF says current guidelines for sucking up ballast water from ports and dumping it thousands of miles away are insufficient. Survivors of voyages, flushed out with a ship's ballast in port, thrive in new habitats because they are freed from predators and parasites it says.
The IMO will thrash out when, where and what depths ships will be allowed to flush and replenish their ballast tanks.
The tougher laws, 10 years in the making, also relate to shipping companies having ballast water and sediment management plans in place and a ballast water record book, detailing when and where ballast was loaded and discharged.
