Quagga mussels have been discovered in Lake Mead. This is a species that originated in the Ukraine and is now found in the Great Lakes and some water bodies in the East Coast. The mussels alter the natural environment by filtering nutrients used by native species. They also foul boat hulls.
Various governmental agencies are trying to stop the spread of Quagga around the Southwest. Their efforts may affect wakeboarders. For example, I understand that some California border stations have gone to 24/7 inspections. I heard that 150 boats were found to have water that was required to be drained. I don't know if this water was in the bilge or in sacks. Mussels were found on three boats, which have been quarantined. I also heard that the National Park Service is thinking about requiring boats removed from marinas at Lake Mead to have their hulls cleaned. While some of this may be a pain, it seems worthwhile to stop the mussels from spreading.
More information on this issue can be found at:
http://www.dfg.ca.gov/quaggamussel/