Colorado Parks and Wildlife officials confirmed this week that New Zealand mudsnails have reached Carter Lake. This marks a concerning expansion of the invasive gastropod along the Front Range. These snails are highly prolific, as females can clone themselves. A single individual surviving on boat equipment or waders can trigger an infestation that reaches hundreds of thousands of snails per square meter.
The ecological impact is significant. These snails consume the algae and aquatic life that native fish and insects rely on. Because the mudsnails offer no nutritional value to predators, they effectively starve local fish populations while clogging critical reservoir infrastructure. Their ability to survive bird digestion and remain viable outside of water for extended periods makes containment a difficult task for wildlife managers.
State officials are now mandating stricter protocols for recreational users. Anyone operating a watercraft at Carter Lake must prepare for mandatory inspections and potential decontamination before entering other bodies of water. These measures aim to prevent the further spread of the species into unaffected watersheds. Wildlife managers are emphasizing the standard clean, drain, and dry procedure for all gear to mitigate the risk.
This is not a new problem for the region, as the species was first identified in the Boulder area in 2004. Recent detections include St. Vrain Creek in 2022. While these snails operate differently than the invasive zebra mussels currently affecting the Colorado River basin, the cumulative threat to local water systems remains a high priority for state environmental agencies. Visitors to Larimer County should watch for new warning signage posted at the reservoir.