Using 126 years of climate data across the United States, we show that the winter survival zone of the potato leafhopper (Empoasca fabae) has not undergone a continuous northward expansion, despite widespread assumptions linked to climate change.

Instead, the overwintering zone fluctuates substantially from year to year while remaining consistently centered in the southeastern United States.

So why are potato leafhoppers often arriving earlier in northern regions? We still do not have the full answer, but our results suggest that warming temperatures in destination areas may be playing an important role, allowing earlier establishment and detection of migratory populations.

This work highlights the importance of annual monitoring of migratory insect populations rather than assuming a permanent shift in their geographic range.

https://doi.org/10.64898/2026.05.25.727670