My Cart


Angler Awareness-The New Zealand Mudsnail

Posted on January 23 2019

Rock Covered with NZ Mud Snails. Photo:

Aquatic Nuisance Species (ANS) are unfortunately being found in waterways through out the country and have various impacts on their surrounding ecosystems.  The Asian Carp has dominated the invasive species conversation throughout the midwest and talk of Zebra Mussels has recently become relevant in the Rockies.  It is important to remember that not all non native species are considered invasive.  A non native species is only considered invasive if it can change the habitat and alter the ecosystem’s services, or if it can crowd out or replace native species.   The New Zealand Mudsnail is an invasive species that can be transported through fishing gear (like uncleaned felt wading boots) and is capable of reaching phenomenal densities in various waterbodies.  

The species is very adaptable allowing it to be introduced and to thrive in a broad range of aquatic conditions.  The issue with New Zealand mudsnails is that they are filter feeders and actively feed on the microscopic organisms that the native inverts (trout food) need to survive.  Something as small as a mudsnail can have a large impact on its ecosystem when they disrupt the bottom of the food chain.   Researchers in Montana have reported populations as large as 750,000 snails per square meter in Yellowstone National Park!  Populations this large can outcompete aquatic insects which native species rely on. 

The snails reproduce asexually which allows them to quickly reach such high densities and has earned them the invasive label.  Most snails are introduced to new waters through fishing gear that was not properly cleaned.  Wading boots need to either be soaked in 409 Degreaser or frozen for 4 hours.  Soaking gear in bleach or letting it dry for a week is not enough to kill the snails DNA!  Responsible anglers and an increase in public awareness are the only ways to stop the spread of this invasive species.  New Zealand Mudsnails have established populations in fifteen states and two Canadian Provinces (including BC!) Luckily NZ Mudsnails have not been found in Alaska.  It is up to us to keep it that way! Please take great care cleaning your gear if you fish in waters that have known Aquatic Nuisance Species populations.

The USGS has an animated map that shows waterbodies with known ANS populations that can be viewed here.

More Environmental Updates:

Join our Mailing List

Sign up to receive our Newsletter!

My Cart

Subtotal: $ 0.00

Your cart is currently empty.