This the  is the first of a short series on invasive aquatic species and their impact on the sport diving community.

We have all heard the term "invasive species" and I don't me aliens from another planet.  Though in some cases they might as well be from another plante they are alien to the US.
There are many invasive species, plants, animals, and aquatic species.  In almost every case they are here in this country - or any country they are not natural to - as a direct result of MAN. There are Zebra and Quagga mussels, the Sea Lamprey, the Round Goby, Asian Carp, the Spiny Waterflea, the Asian Snakehead Carp to name a few.  There are, of course species of plants as well but , since we are divers I'm focusing on the aquatic invaders.

The aquatic species were all either unintentional freeloaders or purposely brought to this country, like the Asian Carp.  The Quagga and Zebra mussels were brought in as freeloaders by freighters bringing goods from Europe, the Eastern Block, or Russia.  The tiny eggs, or "Veligers" came along with the fresh water ballast taken on from the Black and Caspian seas where they are a natural species. That is how they were transported to the St. Lawrence river.
Another story for later ,,,,,

In this missive I want to talk about the Round Goby or "Neogobius melanostomus" for those who speak Latin.

As a regular diver in the St. Lawrence River ("SLR") I have noticed the Goby for the last several years.  The increase in the number of Gobies has increased dramatically in the last couple of years.  In some place the bottom seems to be moving because of all the Gobies.  I've seen them 4 inches long and as thick as 1 1/2 inches! (Almost big enough to get a fillet from!).  They have absolutely taken over in th SLR. 
The Goby is an aggressive species that can grow to a length of 10"!.  The Goby has a large head and a grey body with mottled brown and black blotches on it.  The large eyes and dorsal fin are another feature that make them easy to spot.

They too are originally from the Black and Caspian Seas first spotted, by divers of course in the Great Lakes in 1990.

Now here is a little bit of natures balance at work. The Round Goby eats as it's primary food - the Zebra & Quagga Mussels. (!?!?)  The concern is not that the consumption of the mussels might reduce the viz in the water (we definitely don't want that!) but that the contaminants that are concentrated in the mussels ( they are bi-valves and filter the water for food) will then be even more concentrated in the Gobies that are eaten by game fish - where the contaminants are further concnetrated.

So, how does the Round Goby affect sport divers?

Well,,,,,, not so much - yet.

However, if the population increases to the extent that it reduces the mussels that are keeping the water so clear then it sure will!
Until then they are just something new to watch and monitor in our underwater realm.

Be sure to tune in for the next issue on ,,,,,,,,,, (Que scary music ....)      INVASIVE SPECIES!

Its all about diving
Its all good!

SCOTT.
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