What is a fish or aquatic nuisance species?
Fish or aquatic nuisance species is a non-native species that is introduced and threatens a native species. The introduced fish can breed with the native fish producing a hybrid. The aquatic nuisance species can mean fish, mollusks, animals, or plants relating to waters. These include Golden Shiners, Zebra Mussels and Giant Salvinia.
Nuisance fish and invasive species can negatively impact the habitat by eating the food of the native fish, or consuming all their young. The new fish can also be in direct competition with native species for breeding space.
How is it caused?
Invasive species take in one of these three ways: releasing live bait, illegally stocking fish, and failing to clean the bottom of a boat.
Nuisance or invasive species can be introduced into bodies of water by letting live bait go after fishing. Non-native species then grow and reproduce, displacing native fish. Examples of this: non-native minnows and non-native crayfish getting mixed in with native live bait – and many times distinguishing the two is impossible.
Illegally stocking fish into one body of water from another can be as simple as releasing an overgrown pet fish from a fish tank into the wild. These pet fish can infect native fish with parasites or diseases you may not be aware of. And by failing to clean the bottom of a boat after fishing, a recreational boater or fisherman can unknowingly carry one species from one body of water to another.
What harm do these introduced species cause?
Non-native species of fish can choke out the environment of native species, and wipe them out. They may breed with native species disrupting the genetics by way of hybridizing the natural native species. Other species, such as Zebra mussels, can be hard on infrastructure: they can clog up pipes when left unchecked, and reek havoc on power plants. Invasive species can also transmit diseases such as cholera.
What can be done to prevent the spread of nuisance and invasive species?
There are things everyone can do:
- Proper care of live bait – don’t release it into the lake or waters you are fishing in. Dispose of it properly.
- Don’t move fish – don’t transport your big aquarium or pond fish into lakes or streams. Find a group, person, or shop to donate them to if you have aquarium fish that are too big for your tank.
- Clean anything coming into contact with water – this includes boats and equipment being thoroughly cleaned. Larvae of species can be very small and hidden.
- Inform others – many people do not know what kind of damage that is done to native fish in their area, or may think it is perfectly fine to let any live bait go (after all, it is still alive).