What is a New Zealand Mud Snail


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What are New Zealand Mud Snails?
A New Zealand mud snail (NZMS) is a very small snail (less than ¼ inch long), but given only a couple of years, it can carpet the bottom of lakes or streams. They have no natural enemies in North America, and are parthenogenic (that is, they do not need a mate to reproduce) so all it takes is ONE mud snail to infect a stream.
Example of mud snail density	Why should I be concerned?
	Mud snails were first detected in the Snake River in 1987 and are now spreading rapidly into California with confirmed populations found in Putah Creek, Mokelumne River, Owens River, Hot Creek, and now the Calaveras River. Currently there is no method to eradicate current populations, so the only method of control is to stop spreading.
New Zealand Mud Snail Facts
Choke out native snails and insects. Deprive fish of their main sources of food. Multiply rapidly- within two years, over 3 million snails can result from just one snail. Damage fisheries, particularly salmon and trout, and their native habitats. Spread primarily by anglers who fish an infested area, then leave the area without cleaning their waders and other fishing gear. Can survive up to 25 days outside of streams, if they are in a moist environment, such as inside waders, on muddy wader boots, in live wells, or in cooling systems.
River bottom speckled with mud snails.	What can you do to prevent their spread?
	DFG suggests that anglers treat their gear with at least one of the following methods to prevent spread of NZMS. In addition, DFG warns that snails have been collected on streambanks, well away from the water’s edge. Outdoor enthusiasts and boaters who travel within the riparian areas should also adhere to specific guidelines. To view DFG final report on "Controlling the Spread of New Zealand Mud Snails on Wading Gear" click here.
Outdoor enthusiasts and boaters should follow these guidelines:
Spray gear and boats with Formula 409® All Purpose Cleaner Antibacterial Kitchen Fresh and then scrub with stiff-bristled brush to remove all visible snails. Follow the procedure with a careful inspection of waders and gear to ensure the removal of all adults. Finish with a tap water rinse. Snails frequently collect between laces and tongue of wading boots and in the boot’s felt soles. Freeze waders six to eight hours. It is best to leave them in the freezer overnight to ensure complete mortality. Drying in air temperature over 112 degrees (50 degrees Celsius) for 24 hours will eliminate all mud snails. Alternatively, place gear in water maintained at 130 degrees for five minutes. Mortality of snails varies by exposure to heat and humidity at different combinations. NZMS are not the only aquatic invasive species spread by anglers and boaters. Live bait and the packaging used for some forms of live bait are known to spread other invaders. In addition, invasive aquatic plants and animals are known to hitchhike on boats, their propellers, live wells, and fishing gear. Cleaning all boating equipment is crucial to reducing the impacts from non-native invasive species.
Only YOU can STOP the spread of New Zealand mud snails!
To find out more information on NZMS visit the following websites.
www.wildfiles.com www.protectyourwaters.net www2.montana.edu/	www.fedflyfishers.org www.dfg.ca.gov DFG Information Sheet