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New Zealand Mudsnail Closures - Year Round

New Zealand Mudsnails by keys for size comparison, photo by Dan L. Gustafson

Dry Creek and Boulder Creek downstream of Valmont Road are two of only three locations in Colorado where the non-native, invasive New Zealand mud snail has been found. These areas are closed year round. Please see the closure maps for detail on the closure boundaries.

Mud snails can be spread by boots, waders, a dog's pads, and most anything they come in contact with. The snails are very tiny and thus can easily go undetected as they hitch a ride to a new area. Highly resilient, the snails can survive several days out of water and can withstand a wide range of temperatures.

Because they reproduce by cloning, it only takes one New Zealand mud snail to start a new colony!

Please stay out of the closure areas to avoid the spread of mud snails, and subsequent threats to our aquatic ecosystems.