About Species
  • Tall green aquatic plant
  • Often seen on the surface of the water
  • Sometimes with a small white flower
Last Seen
  • Connecticut River
  • Hudson River
  • Hudson Valley Reservoire
Wanted For
  • Covering water with floating debris
  • Blocking sunlight from native plants
  • Harming fish populations
Favourite Hangouts
  • Boat engines and trailers
  • Fishing live wells
  • Truck bumpers
  • Fish aquariums
A Brief History

Hydrilla was first discovered in Florida in the 1960s, where it has spread across the US ever since. It was first discovered in the Connecticut River in 2017. Since then, it has spread from Connecticut’s border with Massachusetts south throughout the river, putting every other waterbody in Connecticut at greater risk.

Remove if found

Properly dispose of all plants away from the lake in a trash receptacle.

Always CLEAN, DRAIN and DRY your boat, trailer, and equipment before entering Candlewood Lake.

Threats posed by this species

Hydrilla grows fast and dense, taking over an entire freshwater body rapidly. Because it can grow and reproduce so efficiently, it rapidly out-competes native plants that already live in that water body, harming their population numbers dramatically. These plants can also grow to the surface and form dense mats of plant material -- often even denser than the Eurasian Watermilfoil found in Candlewood. This can also make fishing in these water bodies impossible and harm fish species that rely on native plants for habitat.

How does this species spread?

Hydrilla spreads by clinging to boats and trailers that move from one freshwater body to another. For example, if a boat enters the Connecticut river, a strand or even a small piece of hydrilla can get stuck to the boat motor or trailer and if you then take that boat to another waterbody that doesn’t have hydrilla, it can fall off and take root there, beginning the cycle of invasion there too.