May 8, 2014

Aquatic nuisance species such as Asian carp and zebra mussels threaten waterways

TOPEKA – As the warming weather beckons outdoor enthusiasts to their favorite lake or river, Kansans should remember that they play a critical role in helping stop aquatic invaders that threaten lakes and rivers in Kansas and many other states. Aquatic nuisance species (ANS) are animals and plants not native to Kansas that can threaten lake and river ecology, harm native or desirable species, and interfere with our economy. They often hitchhike on the boats and equipment used by unsuspecting people who may unknowingly transport them to a previously uninfested body of water.    

“Zebra mussels, Asian carp and white perch are already established in our state,” said Governor Sam Brownback. “They and other unwanted aquatic species pose serious environmental and economic threats, not only to Kansas waters, but also those of other states. Unwary travelers can spread these species between states. As Vice Chair of the Midwestern Governors Association, I share the concerns of other governors in our region and urge everyone who visits a body of water in any state to take precautions to avoid spreading these species to other waters.”   

“These species don’t respect political boundaries, and they occur in public and private water bodies of all sizes,” said Jessica Howell, Kansas Aquatic Nuisance Species Program Coordinator. “Whatever your destination, it’s important to follow the local laws and regulations concerning aquatic invaders. In Kansas, visit ProtectKSWaters.org for information about aquatic nuisance species and the necessary precautions.”

 There are three primary ways to help stop the spread of ANS:

  • CLEAN, DRAIN, DRY–boats and equipment after every visit to any lake or river (including anything that gets wet, such as tackle, swim gear, footwear, etc)
  • DON'T MOVE LIVE FISH–between bodies of water or up streams
  • DON'T DUMP PLANTS OR ANIMALS IN THE WATER OR DRAINAGE DITCHES– Instead, discard unused bait on dry land or in an approved receptacle, and find a new home with a pet shop or friend for unwanted aquarium species or pets  

In addition to stopping the spread of ANS, it is also important to prevent the introduction of new species such as aquarium pets. In 2013, three tropical fish specimens were discovered in Kansas – an arowana at Lake Shawnee, Topeka; a pacu at Stone Lake, Great Bend; and a tilapia at Mill Creek, upstream from Shawnee Mission Park. None of the exotic fish likely would have survived the winter. However, in 2013 and early 2014, two new populations of Chinese and Japanese mystery snails were reported in Kansas – both of which now have reproducing populations in several Kansas waters. These snails are popular with aquarium and water garden enthusiasts.  

About Asian carp, zebra mussels and white perch

Asian carp – actually three species of carp – threaten waterways and fish populations. They can eat up to 40 percent of their body weight each day, competing with native fish for food and threatening the diversity and quality of other aquatic life.  When young, Asian carp resemble native minnows and shad, which is one reason the Kansas Wildlife, Parks and Tourism Commission adjusted the bait fish regulations to limit the use of wild-caught bait fish. When grown, Asian carp can weigh up to 100 pounds, and they are prone to leaping out of the water when disturbed, posing a real physical threat to boaters. They occur in the Missouri River, have made their way up the Kansas River as far as Lawrence and are moving into other Missouri River tributaries.

Zebra mussels are dime-sized, shelled animals that attach themselves to anything below the water line. In addition to damaging boating and fishing equipment, they’ll foul rocky shorelines with their sharp shells, making it hard to walk or wade along the shore. Also, they can clog water intakes and damage power-generating facilities. In early 2012, the city of Council Grove experienced a temporary water shortage due to a thick layer of zebra mussels coating the inside of the intake tank at Council Grove City Lake. They occur in 22 bodies of water in Kansas and could be spread to others. 

White perch are native to the Atlantic coast of North America and were accidentally introduced into Wilson and Cheney reservoirs as contaminants in shipments of stocked fish. Since then, they have been spread to other reservoirs by unwary people. These perch out-compete native species for food and space and are associated with declines in walleye and white bass populations. They may hybridize with white bass, which they closely resemble.

For more details about aquatic nuisance species in Kansas and precautions that can be followed, visit ProtectKSWaters.org.