There have been numerous inquiries regarding the use of Weevils in the fight against Milfoil. Here is some information that leads the Foundation to believe that Weevils are not the answer for Upper Saranac Lake. Weevils cost a little over $1/bug and require 2-3,000 Weevils per acre to be effective. Upper Saranac Lake is over 5,050 acres in total, although the entire lake would not need to be treated, it is not easily determined exactly how many acres would need to be treated to be effective. With over 44 miles of shoreline, total acreage requiring treatment could easily exceed over 1,000 acres. There is also the potential to restock weevils over several years. Weevils have been effective in some places, but not others, and it seems that the scientist cannot yet predict where they will be successful. It is known that Weevils are most useful in dense growth areas. Fortunately through effective hand harvesting; milfoil on Upper Saranac Lake is no longer in these thick beds. Milfoil, although still a persistent problem, is currently located randomly throughout the lake. It is not uncommon to see individual plants growing with no other plants for hundreds of yards around. In these cases weevils would not be effective as they would not migrate such distances in search of their food source and it is not reasonable to transport weevils to individual plants. Furthermore a Cornell study says that there may be no LONG term reduction in milfoil from the weevils even if there is short-term success.
There is also the hesitation of introducing something into our waters that, although native to North America, is not currently here in Upper Saranac Lake. Past history of doing such introductions on occasion has had long term negative impacts on native populations of fish or animals.
We think it’s important to continue to look at options and adapt as the milfoil evolves. The Foundation still believes that hand harvesting is the most effective, logistically and cost wise, for the control of milfoil. The divers are continually changing the methods they use for harvesting to be more efficient. Next year they are introducing a communication system allowing them to talk to one another underwater as well as surface crew.