Tiny invaders could be big headache for Great Lakes

Sep 1, 2015

Invasive species pose a real threat to the Great Lakes. But not all of them are easy to spot. Current State talks to Joan Rose, co-director of MSU’s Center for Water Sciences, about the risk that invasive viruses could pose to the ecosystem. 

The freighter Hon. James L. Oberstar passes through the Sault St. Marie Locks in Michigan on Tuesday July 7, 2015. Ballast water from ships like this one can bring invasive viruses into the Great Lakes.
Credit G.L. Kohuth

If the Great Lakes put up “most unwanted” posters, they’d be plastered with pictures Asian carp, zebra and quagga mussels, and sea lamprey.

But there are plenty of lesser known threats, including ones that can only be seen under a microscope.  Scientists are increasingly paying attention to the smallest invasive species making their way into the ecosytem--viruses.  Dr. Joan Rose is the co-director of MSU’s Center for Water Research, whose latest research focuses on those viruses.  This segment is supported by Michigan State University's Knight Center for Environmental Journalism. More news about the Great Lakes environment can be found at GreatLakesEcho.org and on Current State every Tuesday as part of our partnership. 

  INTERVIEW HIGHLIGHTS

  Have any invasive viruses that have already caused any damage in the Great Lakes?

The most famous is what’s known as VHSV, it’s the viral hemorrhagic septicemia  virus. It has caused a lot of fish kills, and has been spread through the Great Lakes so that is probably our most famous viral invader to date.

  Will the ballast water standards that have been passed have to be strengthened in order to contend with this situation? 

We believe these policies will have to be changed to address viruses. They are looking at treating ballast water on the ship. We have all kinds of new water technology that can probably kill viruses. But the question is which viruses do we want to kill and how much do we want to treat the water? So we’ve got to answer those questions.

Is there any technology that can be affective at wiping these viruses out before a ship enters the Great Lakes?
 
I think there’s some technology that uses new types of membranes, ozone and UV disinfection that could actually destroy the viruses in the ballast water before you discharge it. Or maybe even destroy the invaders at the ship’s location where it has to pick up or exchange the ballast water. So I think there’s all kinds of new things happening in this arena. 

 Do these invasive viruses pose any risk to human health?

Under the Safe Drinking Water Act we have addressed viruses already. Any treatment that uses surface water has to treat its water to reduce viruses and activate them. So we do have policies in place to drinking water to reduce viruses to a level that we deem safe, at least in the U.S. 

I think that globally from public health, they’re starting to look at things like Rotovirus, which is very widespread. 
 
On the ballast water side, the International Maritime Organization is starting to produce guidelines. This is a global commerce issue. So if California, which is one of the larger ports, says we need to control viruses, they’ve got ships coming from all over the world. So now the global community is going to say “Oh, we want our ships to be able to land in California safely.” We want them to be able to land in Singapore and Japan. It’s starting to reach the global discussion.