JACKSON, Wyo. — Mussels, and bullfrogs, and thistles — oh, my!
This week is National Invasive Species Awareness week, which Grand Teton National Park (GTNP) and the Wyoming Game and Fish Department (WGFD) are both observing.
“Invasive species can: outcompete native plants and wildlife for food and habitat; require intensive monitoring and costly management; and alter soils, water systems, and natural ecological processes,” GTNP posted to social media. “Plants like spotted knapweed and cheatgrass can spread rapidly in disturbed soil along roads and trails. Cheatgrass dries out earlier than native vegetation, increasing wildfire risk and reducing the quality of available forage for wildlife.”
In addition to those plants, GTNP sees invasive species ranging from bullfrogs to aquarium fish. The park is also extra vigilant about monitoring incoming watercraft for aquatic invasive species including zebra and quagga mussels, which can be extremely difficult to eradicate once established in a waterway.
WGFD is also focused on aquatic invasive species. This week, the agency stated on Facebook that it employs more than 60 dedicated technicians to operate inspection stations from March to November, “checking watercraft to ensure they aren’t harboring any unwanted plants or animals (they did over 76,000 inspections in 2025!).”
Earlier this month, WGFD announced that it had elected to close a popular pond near Casper following the confirmed presence of invasive New Zealand mudsnails in October.
Both agencies urge public participation in slowing the spread of invasive species. GTNP advises taking the following preventative steps:
- Clean, drain and dry all boats, waders and fishing gear
- Brush mud and seeds from boots, bikes, pets and vehicles
- Stay on designated trails and roads
- Never release pets, bait or aquarium species into the wild
“Healthy parks depend on informed visitors,” GTNP posted. “Join us in protecting the Tetons by learning how you can help stop the spread.”
