An oil tanker makes its way to Valdez. As ships begin to use newly opened sea routes, more invasive species could find their way to Arctic waters. - Photo provided by the Smithsonian Environmental Research Center

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Invasive species threaten ecosystems in the Arctic

June 6th, 2014 | Jillian Rogers Print this article   Email this article  

There are millions of stowaways headed for the Arctic.

Sea-dwelling organisms that could wreak havoc on Arctic ecosystems are hiding out in and on ships that, more and more, are using shipping routes in the North.

A report published last week by Whitman Miller, an ecologist at the Marine Invasions Research Laboratory at the Smithsonian Environmental Research Center, stated that invasive species are destined for the Arctic with the influx of vessels.

Melting sea ice has opened routes in the Arctic — the Northwest Passage and the Northern Sea Route — making a quicker path from one side of the world to the other.

"The economic draw of the Arctic is enormous," Miller wrote in the report. "Whether it's greater access to the region's rich natural resource reserves or cheaper and faster inter-ocean commercial trade, Arctic shipping will reshape world markets. If unchecked, these activities will vastly alter the exchange of invasive species, especially across the Arctic, north Atlantic and north Pacific oceans."

Organisms from ports can cling to the undersides of a ship's hull or hunker down in the large tanks of seawater inside a ship.

"Ships are moving over the Arctic and can carry a tremendous number of species in their ballast water ... connecting ports in a way that they have not been connected before," Miller said last week.

The danger lies in the likelihood of these critters taking over their new environment and killing off native species.

Miller said for the past century or so, ships traveling between oceans got from one to the other by way of the Panama or Suez Canals. Both of those courses offered warm, tropical water, and that temperature stress would often kill or weaken hangers-on.

"In the Panama Canal, species on the hulls of ships also had to cope with a sharp change in salinity, from marine to completely fresh water," read the report. "The Arctic passages contain only cold, marine water."

As long as species are able to survive cold temperatures, the odds of surviving in the Arctic are good.

Water in ballast tanks is used to balance and stabilize ships. Ocean liquid is sucked in and spit out accordingly, organisms and all, depending on the ship's load and conditions.

"Typically this is done in coastal waters and in ports where you're offloading or loading cargo, and in doing so, you're not just taking water, you're taking all the biological and planktonic communities with that water," Miller said.

"The potential biological cocktail that you can concoct is pretty staggering," Miller said.

Ballast tanks on big ships can hold up to about 100,000 metric tons of water, Miller said. And once you start multiplying that by the number of shipping vessels in the water heading north, the amount of water and living organisms exchanged is enormous.

When a species arrives in a new environment, they have no established predators, said Gary Freitag, a marine biologist with the Marine Advisory Program in Ketchikan.

"They have a tendency to prey on the native species, eat the food of the native species, and take over habitat of the native species," he said. "And in most cases, they're a little more resilient because if they're able to establish in an unfamiliar habitat, they're pretty flexible critters."

If left unchecked, invasive species spread rapidly with little course of action because they can be difficult to detect until the damage is done.

"We don't quite know what will happen in the Arctic because we haven't experienced invasive species really in the Arctic yet."

A few years ago, Freitag traveled to the North Slope to collect data from the waters off Point Barrow. Much of their efforts were stymied by a storm, he said, but he is planning more work in the North.

A current threat in other parts of Alaska is the European green crab, a hardy crustacean that can thrive in a variety of climates.

A variety of other crabs, and tunicates — the most common called "rock vomit" — are also on the list of invasive species infecting Alaska waters.

Some of the most-wanted are found clinging to the ship's hulls, while some ride along in ballast tanks.

In one year, around 50 or 60 million metric tons of water comes to the U.S. from overseas via ballast water.

In Alaska, between 2009 and 2012, 14 million metric tons of ballast water was discharged annually in ports, said Danielle Verna, a graduate fellow with the Smithsonian Environmental Research center. Verna has been studying invasive species in ballast water for years and has conducted research in Valdez and Cordova.

"When you're talking about risk of invasive species in the Arctic, you have to consider the increased vessel traffic," she said. Part of her thesis work looked at various factors that influence risk, such as the age of ballast water, the similarities between the source and where the water is discharged, and the species richness in the source port.

"Those are all factors that you would have to consider in an Arctic environment," Verna said.

In the U.S. there are mandatory ballast water management regulations in place. Ships coming to the U.S. from overseas are required to exchange ballast water with open-ocean water at least 200 nautical miles from land.

The idea behind that, Miller said, is that organisms picked up in the open ocean will have a lessened chance of survival when dumped out into a coastal ecosystem, and vice versa.

A couple of years ago, the U.S. Coast Guard came out with a ruling where the allowable number of living organisms dumped out in ports via ballast water was limited. Reducing the number can be done by onboard treatment systems in the form of chemical additives or filtration methods.

"The beauty of an onboard treatment system is that it (allows) that ship to operate anywhere in the world without the fear of introducing organisms from other places," Miller said, adding that organisms have been brought elsewhere from the U.S. and become invasive species.

These rules are enforced at ports across the U.S. for commercial ships. Ships are supposed to report ballast activity to the National Ballast Information Clearinghouse, which then analyzes the data and provides information to the U.S. Coast Guard.

"The technology is lagging behind the regulations so currently there are no approved onboard treatment technologies," said Miller, who is also the director of the National Ballast Information Clearinghouse.

Other preventative measures crews can take are simply not discharging ballast water in the coastal system.

"There are regulations on the books and they are enforceable," Miller said, adding that many countries enforce similar laws.

A ballast water treaty is on its way to being ratified by the maritime branch of the United Nations that would see global standards for ballast water management.

However, ballast water management regulations don't help with species that hitch rides on ships' hulls.

"We've been working on ballast water issues for 30 or 35 years and I think we're finally on the right track."

Hull fouling species like barnacles, mussels, sponges, algae, etc., are a little trickier, Miller said.

Typically ships use a coating on the ship's hulls, some are toxic to hitchhiking sea creatures, while some coatings make the surface too smooth for things to latch onto.

"Currently it's a really difficult problem because it's not like you have the opportunity to filter the water; partly it's a process of good hull husbandry and making sure that your ship is clean."

Until now, the Arctic has had relatively low exposure to invasive species. That's the good news.

"Now is the time to advance effective management options that prevent a boom in invasions and minimize their ecological, economic and health impacts," said the report's coauthor Greg Ruiz.


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