So this weekend I was helping take our boat off of Lake Mahopac when I noticed these little guys on the outdrive of my family's boat.

For those of you that don't know what this little invasive creature is, it is a Zebra Mussel (Dreissena polymorpha). Zebra mussels are freshwater mussels that are originally native to Black and Capsian seas (Southern Russia). They were believed to be introduced to the United States begun by mid-1800's , but is unrecorded (Simberloff, 2013).

Zebra mussels get their name from the striped pattern on the shells. The color of the pattern can vary to the point of having only dark or light colored shells and no stripes. They are typically found either attached to objects/surfaces or at the bottom of a fresh body of water opened (which means it is dead). Zebra mussels are an invasive species that was brought to the U.S. through ballast water in ships (Simberloff, 2013).

Zebra mussels have harmful impacts in many ways, including biological, ecological, and economic impact. For instance, zebra mussels settle in dense aggregations will readily attach themselves to native mussel. This behavior is known as bio-fouling and with the spread of these creatures, native mussel populations have been on the decline (Simberloff, 2013).

Also, zebra mussels are filter feeders. What this means is that they feed by straining suspended matter and food particles from water over a specialized filter. At first in some areas this was seen as a positive impact. It was thought that it was a good thing that the filter feeders cleanded up the water, improving clarity, but the negative impact out weighs this temporary positive impact. When zebra mussels filter feed at their colossal rates, they are feeding on phytoplankton. This decrease the densities of phytoplankton, which other species feed on, as well as clearing the water so much that there is an increased vegetation growth (Simberloff, 2013).Lastly, zebra mussels will settle on any stable substrate, which include artificial surfaces such as cement, steel, ropes, boat, etc. Here they can establish sizable populations. This can cause problems such as fouling, clogging water pipes, getting into boats water intakes (which will cause the boat to overheat). According to Daniel Simberloff, "costs (due to zebra mussel damage) to date is estimated at billions of dollars."

Zebra mussel have a very high potential to spread elsewhere in the U.S., but us completely preventable. Some ways that we can prevent the spread include removing visable vegetation from items that where in the water, do not reuse bate that was exposed to infested water, dry equipment for at least 48 hrs. before using in uninfested water, examine your boats exterior for mussels, flush engine cooling system, bilge, and live well with hot water, and clean your boats with high pressure and steam. Some larger lakes have inspection stations at boat launches, and now I think Lake Mahopac should implement a similar system.

For more information, go to https://nas.er.usgs.gov/queries/factsheet.aspx?spe...

Reference

Simberloff, D. (2013). Invasive Species: What Everyone Needs to Know. New York, NY: Oxford University Press.