This sign gave Marash Girl pause on Saturday when she stopped at the McDonald's on the Massachusetts Turnpike going west, just before the Lee Exit. Curious, rather than calling the number on the sign (her cell phone doesn't get reception in the mountains), she asked her cousin, Staten Island Baby, exactly what the threat was. It seems that the tiny Zebra Mussel (so called for its striped shell) is taking over Massachusetts fresh water rivers and lakes and using up the food supply that would otherwise be sustaining native species. Staten Island Baby reports that "Zebra Mussels attach themselves to hard surfaces including boats and water intake pipes and also to crayfish, turtles, and native mollusks. They are an invasive species and threaten native wildlife and upset ecosystems. Communities have spent millions of dollars trying to stop the invasion." According to NationalAtlas.gov, the Zebra Mussel is native to Poland, the Balkans and Russia, and "first appeared in North America in 1988 in Lake St. Clair, a small water body connecting Lake Huron and Lake Erie. Biologists believe the zebra mussels were picked up in a freshwater European port in the ballast water of a ship and were later discharged into the Canadian side of Lake St. Clair." Why does the small mollusk pose a threat to our native wildlife and ecosystems? It appears that a "female zebra mussel begins to reproduce at 2 years of age, and produces between 30,000 and 1 million eggs per year" which translates into the fact that a colony of Zebra Mussels "may be filtering all the water in a lake or stream in a day," thus depriving native species of the nutrients they need for sustenance. So if you're a boat owner, call the number given on the sign above, or simply wash the bottom of your boat before you move from one body of water to the next, and if you're not a boat owner, spread the word, because, after all, who knew?