Moving live fish, aquatic plants, or mussels from one body of water to another can cause irreversible damage to the ecological balance of Georgia lakes, rivers and streams.
AQUATIC NUISANCE SPECIES: Examples In and Near Our State
The quality of largemouth bass, bream, and crappie fishing in Georgia mountain lakes has declined following the illegal introduction of blueback herring.
Georgia's best smallmouth bass fishery, Lake Chatuge, was lost to illegally-stocked spotted bass. The only remaining smallmouth bass fishery, Lake Blue Ridge, also is threatened by spotted bass competition.
The genetic purity of shoal bass is compromised due to the illegal introduction of spotted bass on the Flint River.
The popular redbreast sunfish and bullhead fisheries in the Altamaha River were decimated by the invasive and illegally-introduced flathead catfish. The Satilla River redbreast sunfish population also is threatened by the illegally-introduced flathead catfish.
The zebra mussel is moving south. These mussels, introduced in the Great Lakes in 1985, are now found in Tennessee and Alabama, and are likely to be carried into Georgia on boats or by individuals. Zebra mussels could adversely impact Georgia's native mussels (many of which are endanged), clog intakes for drinking water, power plants and outboard motors; costing millions of dollars in damage, control and abatement.
Asian Carp (both Bighead and Silver) are exotic fish species invading and causing harm to native fishes and mussels throughout the Mississippi River basin and have the potential to invade up to 31 states, including Georgia. These fast growing filter feeders can dominate a fish community, impact native species, alter water quality and harm important commercial and recreational fisheries. Asian carp are now found in the Tennessee River basin; which falls (in part) in north Georgia. The U.S. Fish and Wildlife Serivce is monitoring Asian carp movements up the Tennessee River basin using eDNA. Asian carp have not yet been discovered to inhabit Georgia waters, but their proximity to state waters is of particular concern. Additional information here and here.
Georgia Trout Populations are threatened by the following newly occurring invasive diseases:
Whirling Disease: This disease is found in rainbow trout from the Watauga River in North Carolina in 2015. Whirling disease can cause 90 percent or greater mortality of young rainbow trout and can have serious impacts to wild and hatchery trout populations. The disease is caused by the microscopic parasite Myxobolus cerebralis, which damages cartilage and skeletal tissue in trout causing diseased fish to swim in a "whirling" motion. While often fatal to juvenile trout, the disease is not known to affect humans or pets, and eating an infected fish is not known to cause any harmful effects. More info here. For more information on preventing the spread of whirling disease, click here.
Didymo: This disease, also called rock snot, is a freshwater diatom that produces thick algae mats along stream bottoms. The mats can be so thick that they can alter stream habitats and make fishing difficult. Didyo can be spread easily from one water body to another. This microscopic algae was recently found in North Carolina for the first time and is a threat to Georgia streams and rivers. More info here. For more information on preventing the spread of Didymo, click here.
Gill lice: These lice, a parasitic crustacean that attach to the gills of trout, recently were found in trout in North Carolina. In high concentrations, these lice can impact respiration and the health and survival of the trout. More info here.
Giant salvinia (Salvinia molesta) is also known as Kariba weed, African pyle, aquarium watermoss, koi kandy. This plant is one of the worlds most noxious aquatic weeds and is notorious for dominating slow moving or quiet freshwaters. Its rapid growth, vegetative reproduction and tolerance to environmental stress make it an aggressive, competitive species known to impact aquatic environments, water use and local economies. Giant salvinia is native to South America and has been introduced to several countries around the world (including the US). Giant salvinia has been found in Georgia at four locations since 1999. More info on this plant here .
Hydrilla (Hydrilla verticillata) is an aquatic plant species that is native to Eurasia and was believed to have been first introduced into the US in the 1960s. It is also known as Florida elodea, water thyme, water-thyme, and waterthyme. This plant is present in several Georgia waterbodies around the state. Research has recently been done to investigate potential links between hydrilla infestations and oubreaks of an often fatal disease that can affect birds. Most recently, a link to hydrilla has been suspected in bald eagle deaths in the Southeastern US. This research has examined avian vacuolar myelinopathy (or AVM) and eagle deaths in South Carolina-Georgia reservoirs. More info on this plant here and here.
Channeled Apple Snail (Pomacea canaliculata) are originally native to South America. These exotic snails have been found in Georgia, California, Florida, North Carolina and Texas. The shells can be near baseball-sized (80 mm or over 3 inches). The large egg masses are laid on vegetation or trees and are bright pink or orange in color. Egg masses can be 2 to 3 inches long and may contain 200-600 eggs. More info here and here.