The Problem of Invasive Species

I'm often asked what is the most pressing problem 

for our Great Lakes. 

My answer:

Invasive species.

When a new species is dropped into an ecosystem in which it has never existed, it often has a huge survival advantage and can toss the entire system out of balance for a time. 

As I've walked the shorelines of our vast inland seas, I've often seen evidence of the destructive power of invasives.

While vigilance and legislation (e.g. strict ballast water treatment laws) can help prevent transport of new species into the Great Lakes Basin, what can be done to control them once they have established a hold in the lakes?

INVASIVEORE.ORG has some ideas...

and recipes!

From their website:  

Our mission here at Invasivore is to be your one-stop guide for devouring Invasive Species, those organisms which have been moved around the world, damaging their new surroundings.  Think of it as reasonable revenge for the harm these species cause.  The word “invasivore” comes from combining “Invasive Species” with the latin for “devour” as in “carnivore”.  Thus invasivore = one who eats invasive species.

From prehistoric times, humans have had an amazing track-record of severely reducing the populations of species we eat.  Indeed, it seems that much of the time we can’t stop ourselves.  Can we tap that hunger to reduce the impacts of harmful invasive species?  We think the answer is Yes!

Alewife, an invasive species native to the Atlantic Ocean long established in the Great Lakes

Check out all the recipes on their site, including one for 

Alewife & Cucumber Crackers.

Annual Lake Michigan Bottom Survey

That's me on board the SS Grayling

I was thrilled to be invited to come aboard the vessel used for the USGS annual bottom survey of the Great Lakes!

This year, the scientists used an underwater camera

Dr. David "Bo" Bunnell of the Great Lakes Science Center

The boat is outfitted with specialized machinery for the trawl

Yellow perch

USGS logo on the Grayling

Alewives

Dr. David "Bo" Bunnell assesses the catch

Quagga mussel

A deep water species, the slimy scalpin

Check out the video from this day out on the lake below. This experience will be part of my newest book, 
A 1,000-MILE GREAT LAKE 
ISLAND ADVENTURE, 
which will be released in 2015.

Did You Know...

...there are over 150 invasive species in the Great Lakes. These range from fish like the alewife, to plants like the purple loosestrife, to mussels like the zebra and quagga.


...zebra mussels are native to the lakes in southeast Russia. They have been transported to the Great Lakes in the ballast water of ships.



...zebra mussels can produce up to 1 million eggs a year. All of the white in the photo here is from dead zebra mussel shells both in the water and piled up in a long windrow. This was just south of Cross Village, Michigan.


















This photo shows a mixture of zebra and snail shells along with stones from the shore of Lake Michigan.

Invasive Species

The Great Lakes ecosystem is vulnerable to invasive species. The photo to the left is of a mass of zebra mussel shells. This species was introduced into Lake St. Clair in the mid-80s and quickly spread throughout the lakes. Native to the Caspian Sea region, this mussel was brought here like most invasive species to the lakes, in ballast water.

It occupies a niche in the ecosystem that was not occupied, so the mussel population exploded.

The second photo is of an alewife. This is a fish native to the Atlantic. If you've ever been on the beach in the spring after a quick warm-up in the temperature of the lake, you may have seen massive die-offs of the alewife population. They cannot handle the stress of a quick change in temperature.

A new regulation was recently put into effect that requires all vessels coming into the Great Lakes system (from other fresh water systems) to rinse out their ballast tanks with salt water. This will purge most fresh water species before they can be transported into the Great Lakes, but it is not a perfect solution. This point is illustrated by the alewife, an Atlantic Ocean species.

So, what is the solution?

There are ways to treat ballast water to insure that no live creatures or plants survive to thrive in the Great Lakes. The water can be treated chemically or with UV light. What needs to happen for this to happen? Lisa Jackson, the new head of the EPA, vowed to review regulations for the Great Lakes. She could enact a new ballast water regulation. While there is no pending legislation in Congress, it is a good idea to alert your representatives to your concern over invasive species in the Great Lakes.

Why should you care? Zebra mussels, alone, have required up to 5 billion dollars to contend with since they arrived. Water intake pipes used to bring in lake water (for cities like Chicago) or for industry (like the three nuclear power plants on Lake Michigan) get clogged with the mussels and have to be cleaned. These mussels also compete for the food that small fish eat, making it tougher for fish to thrive.

It is virtually impossible to eliminate a new species once it has been established in the lakes. It is surprisingly easy, though, to prevent their arrival in ballast tanks.