SANDPOINT, ID — The Idaho Department of Lands has confirmed that invasive spongy moths have been detected in Sandpoint for the second year in a row, marking the first indication of a possible reproducing population there since 1991.

Three male European spongy moths were trapped in 2025 during intensive follow-up monitoring near Oak Street, Division Avenue, Monroe and Poplar, and the Syringa Creek–Chuck Slough area. The moths were confirmed through USDA APHIS DNA analysis. One moth was captured in the same area in 2024.

IDL says the repeated detections are unusual. More than 20 initial catches have occurred statewide since the 1990s, but none resulted in additional moths being found in delimitation traps. Ground surveys this fall did not uncover egg masses or feeding damage, but IDL estimates that if a population exists, it is very small.

More Traps Coming in 2026

IDL will expand monitoring next summer, placing 50 traps per square mile within half a mile of the capture sites and 36 traps per square mile in surrounding zones. Traps will be checked mid-season to ensure new detections are caught quickly. Any eradication effort would be coordinated with USDA APHIS.

Residents should expect to see more bright green and orange cardboard traps throughout Sandpoint and are asked not to disturb them.

To help prevent the spread of invasive insects, IDL urges residents to avoid moving firewood long distances, inspect outdoor items before relocating them, and report suspicious insects or tree damage.