Jul 23, 2008 — Invasive species have been a problem in the North Country since the first zebra mussels arrived from the Caspian Sea in Asia. These and many other invasives came up the St Lawrence Seaway in the ballast tanks of ocean going freighters. A recent study found that throughout the Great Lakes region industries from sport fishing to forestry could lose $200 million as invasives crowd out indigenous species. Trans-Atlantic ships coming up the St Lawrence are now required to flush their ballast tanks before entering the Great Lakes. But there are other more local efforts to stop the spread of invasives, even from one Adirondack pond to the next. And one of these efforts is today's Heard Up North.