Invasive clams resurge in US lake despite massive eradication effort

Lake George in New York launched an ambitious effort in 2011 to combat an infestation of invasive Asian clams by deploying over 700 benthic barrier mats across a five-acre treatment zone. The intervention proved remarkably effective, eliminating 97 percent of the clams in the targeted area and offering initial promise for long-term control of the species, which threatens the lake's native ecosystem.

However, the apparent success was short-lived. By 2019, just eight years after the treatment concluded, the clams had rebounded and spread significantly beyond the original containment area. Environmental monitoring revealed the invasive species had established populations at 27 distinct sites throughout the lake, indicating the barrier treatment had failed to provide a permanent solution.

The resurgence has prompted a strategic shift in management approaches. Rather than attempting another large-scale eradication effort, authorities have redirected focus towards monitoring the clams' continued spread and assessing their impact on Lake George's aquatic ecosystem. The challenge reflects broader difficulties in controlling invasive species once they establish themselves in natural water bodies, particularly when initial interventions prove only temporarily effective.

Lake George's experience underscores the complexity of managing invasive aquatic species and the need for sustained, adaptive management strategies rather than single-intervention approaches.