'Swish and spit' looks effective on invasives species
DULUTH -- The first saltwater ship of the 2012 season left the Twin Ports last week with a load of wheat bound for Belgium, and there's some good news on what the Arubaborg probably did not leave behind.
After a seemingly endless stream of foreign invaders that hitchhiked across the oceans in the ballast of saltwater ships, the Great Lakes haven't seen a confirmed new invader since 2006. That's either a string of good luck or some evidence that a program requiring ships to exchange their ballast at sea is working.
It's a startling reversal of fortune for the Great Lakes, which saw 185 foreign species invade over the last century, the Duluth News Tribune reports (http://bit.ly/HL3Ws7). Since the St. Lawrence Seaway opened in 1959, more than half of the new species are believed to have arrived in ships' ballasts. A decade ago researchers were finding a new species in the Great Lakes on average every 28 weeks -- from goby and ruffe to quagga mussels, bloody red shrimp and the fish-killing VHS virus.
The ballast exchange program, often called "swish and spit" after the dentist office order, is aimed at killing freshwater critters that may be hiding in ballast tanks with a heavy dose of saltwater. The exchange, which started as voluntary in 1993 but has been required by the U.S. and Canadian governments since 2006, is done with the ships still well out at sea.
"That salinity shock is unbelievably powerful. It's incredibly toxic to those freshwater species," said Dale Bergeron, maritime transportation specialist for Minnesota Sea Grant in Duluth.
It's those freshwater species from other continents that can thrive and wreak ecological and economic havoc in the freshwater ports and estuaries across the Great Lakes -- if they make it here alive. Supporters say swish and spit is killing up to 98 percent of the freshwater organisms hiding in ballast tanks.
But the National Wildlife Federation and other groups say assuming swish and spit is working to stop all species is naive.
There's no way of knowing whether it's working because there is little organized effort to search for new species across the lakes. And there's no confirmation of what remains in the tanks. They note that it often takes years for new species to begin to expand and flourish in a new port. It's often not until that big expansion that species are confirmed as here to stay.
Meanwhile the Environmental Protection Agency has noted 58 foreign species that still present a moderate or high risk of invading the Great Lakes in ballast tanks.
"It's great news that we haven't had a confirmed new invasion for six years. And no one is going to argue that ballast exchange isn't helping," said Jennifer Nalbone, invasive species director at Great Lakes United. "But no one can argue either that we can stop now, that this is enough. The risk factor for another zebra mussel or goby getting into the lakes is simply too high without adding another level of protection."
That next level of protection is on its way in the form of mandatory on-board ballast water treatment, at least for the 12,000 saltwater ships that enter all U.S. waters annually. Two federal agencies are about to finalize, yet this year, new regulations requiring saltwater ships to treat their ballast with some sort of on-board system using chemicals, ultraviolet light, filters or other technology to kill any critters in the tanks.
The U.S. Coast Guard and Environmental Protection Agency are following separate but parallel paths to require ballast treatment by 2014 in new ships and starting in 2016 for older ships. The rules phase in the installation requirement depending on when a ship is scheduled for a major dry-dock overhaul. But that could take until 2021 by some estimates, a schedule that's too long for some.
It's not just the timing, but also the details of the federal rules that environmental groups challenge. Both the Coast Guard and EPA rules adopt the proposed International Maritime Association Standard for killing living organisms inside ballast. But critics say that IMO standard is too weak and that many tiny critters could still pass through. California's state ballast standard, for example, is 100 times stricter than the IMO standard.
Bergeron said California's standard, as with New York's now-delayed standard, are unachievable with on-ship systems and impossible to measure.
"The EPA looked at that long and hard, as did the Coast Guard, and they had scientific advisers weigh in, including the National Academies of Science, and they said it just isn't possible to get to that level" of killing living organism in ballast water, Bergeron said. "When the science and technology catch up, the regulations can catch up. But we aren't there yet."
"This is a landmark year for ballast control in the U.S. We now have our first standards for protection. It's a big step forward," Nalbone said. "The problem is that the IMO standard still allows too much to pass through in each ship. We believe the technology is there to meet a much higher standard. And the pressure to stay at this weaker IMO standard is going to be great. The (shipping) industry isn't going to want to budge."
Neither federal rule initially calls for ballast treatment on freighters that remain on the Great Lakes. Lakers are exempt from both federal timelines, although the rules imply they will be included in the future.
"It's not a pass. It means that lakers will be brought under the rules when there is some sort of technology found that will work," Bergeron said.
Officials for the Great Lakes carriers note they have never brought a new species into the lakes. But Minnesota officials say that's not the point. Lakers, which have much larger ballast tanks and release much more water than oceangoing ships (and which call on the Twin Ports far more often than salties) clearly are a potential pathway for invasive species to move great distances very fast.
Jeff Stollenwerk, industrial water section manager for the Minnesota Pollution Control Agency, said Minnesota is standing by its existing law that will require lakers to treat ballast water by 2016. No other state or federal agency has so far set a date for the big boats to meet a ballast standard.
"This is a big issue for Lake Superior because more than 95 percent of the ballast water that's released in the Twin Ports is from lakers," Stollenwerk said. "As invasives are introduced in the lower lakes, we see them moved around and transported into Lake Superior. We see the Great Lakes carriers playing an important role in that redistribution of species that otherwise might never get to Lake Superior.
JOHN MYERS is a writer for the Duluth News-Tribune. The Bemidji Pioneer and the News- Tribune are Forum Communications Co. newspapers.