An evaluation Zequanox® efficacy and application strategies for targeted control of zebra mussels in shallow-water habitats in lakes

Abstract

Publication: Management of Biological Invasions

This 2015 field study evaluated the effectiveness of Zequanox®, a biopesticide made from a naturally occurring bacterium, for controlling zebra mussels in shallow lake environments. Conducted at Deep Quarry Lake, Illinois, in 2012 and 2013, researchers applied Zequanox to enclosed areas of the lake using PVC barriers and monitored zebra mussel mortality over time. Results showed consistently high effectiveness—over 90% mortality of adult mussels and veligers (larval stage) in treated areas—while control sites showed minimal impact. The study confirmed that Zequanox does not harm water quality parameters such as pH, ammonia, or conductivity, although temporary oxygen reductions were noted where water movement was restricted by barriers.

Zequanox proved effective even on natural substrates and across different mussel sizes. However, its reach was more limited in shallow areas (<0.6 m depth), suggesting the need for targeted applications in those zones. The study highlighted Zequanox's promise for use in natural lake environments as a selective and environmentally safe method for zebra mussel control, especially in high-value or early-infestation areas. This was the first open-water evaluation of Zequanox in a natural lake and laid the groundwork for broader use and further testing under diverse environmental conditions.