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Aquatic Nuisance Species


What Are Aquatic Nuisance Species?

Definition: "... a species that threatens native species' abundance or diversity, stability of aquatic systems and commercial or water recreational use."

Did You Know?

  • Utah is the 2nd driest state in the country with an average of 13 inches of precipitation annually.
  • Pollution and urban sprawl are the main threats to Utah's limited water resources.
  • One of the most recently recognized threats is the introduction of Aquatic Nuisance Species (ANS).
  • We focus on these species because they pose a major threat to our water resources and we may be able to stop their spread or introduction.

Primary Threats in the State of Utah


Purple Loosestrife
Lythrum salicaria

Purple Loosestrife - Copyright USDA, NRCS Plants Database

Distribution: Small, isolated communities exist throughout Utah.

Identification: Flowers have five or six purple petal surrounding small, yellow centers. Indvidual flowers make up each flower spike. Leaves have smooth, downy edges, and are arranged in alternating pairs; but they may appear in groups of three. Mature are plants 3-6 feet tall.

Problem: Purple Loosestrife is a hardy perennial wetland plant introduced from Europe. The plant invades marshes and lakeshores, replacing cattails and other native wetland plants by forming dense stands that have no value as wildlife cover, food or nesting habitat.

Means of Spreading: Seeds disperse from gardens and nurseries into wetlands, lakes and rivers. Once introduced, seeds are easily spread via water or wildlife. Humans also spread seeds through equipment and clothes.

 

Eurasian Watermilfoil
Myriophyllum spicatum

Eurasian Watermilfoil - Copyright USDA, NRCS Plants Database

Distribution in Utah: Populations are found in Otter Creek Reservoir and Fish Lake.

Identification: Leaflets have a distinct feathery appearance and are arranged in whorls of 4 around a long slender stem growing up to six inches long. Typically, leaflets grow up to an inch and are usually dark green, but sometimes have a reddish tint.

Problem: In nutrient-rich lakes, Eurasian Watermilfoil forms thicks stands of tangled stems and vegetative surface mats. The plant can interfere with recreational activities such as boating, fishing, and swimming and can often crowd out important native plants.

Means of Spreading: Eurasian Watermilfoil may become entangled in equipment. Stems can become lodged in any watercraft or sports equipment that moves through the water. Boat trailers are especially susceptible to transplanting this plant.

Zebra Mussel
Dreissena polymorpha

Zebra Mussel

Distribution in Utah: No known populations are found in the state.

Identification: Small fingernail-sized mussels with a yellow and/or brown D-shaped shell with alternating bands of color. These mussels grow up to two inches, but are usually under an inch. They grow in clusters containing numerous individuals, and are generally found in shallow water. Zebra Mussels are the ONLY freshwater mollusk that firmly attaches itself to rocks, boat hulls or other mussels.

Problem: Zebra Mussels threaten industrial and public drinking water use and activities such as boating, swimming and fishing. They clog power plants, water treatment facilities and irrigation systems. They also consume large amounts of plankton, which alters the food chain.

Means of Spreading: Microscopic larvae may be carried in livewells, bilge water, bait buckets or on diving gear. Adults attach to boats or other water equipment.

Stop the Spread, Stop the Introduction!

 

Why Are ANS Harmful?

These species are harmful; they can:

  • Impact recreation, power and water operations.
  • Disrupt the natural ecosystem balance.
  • Displace native species
  • Alter native species' food webs.

How Can I Help?

With this guide, you can learn to recognize Utah's primary ANS threats and help stop their spread or introduction.

Before leaving a water body, here's what you can do to help control ANS:

  • Inspect your boat and equipment. Remove any plants or animals.
  • Drain water from the motor, livewell, bilge, or transom well.
  • Never release or transport live aquatic species from one water body into another.

For More Information...

Please call the Division of Wildlife Resources at (801) 538-4700 for ANS information related to prevention regulations, control methods or permits. Also, you can contact other members of the Utah Aquatic Nuisance Species Action Team to get more information. These members include:

  • Central Utah Water Conservancy District
  • PacifiCorp
  • U.S. Bureau of Reclamation
  • U.S. Fish and Wildlife Service
  • U.S. Forest Service
  • National Park Service
  • Utah Department of Environmental Quality
  • Utah Department of Agriculture and Food
  • Utah Division of Wildlife Resources
  • Utah Division of Water Resources
  • Utah Water Users Association
  • Utah State University
  • Salt Lake County Fish and Game Association