ROCKTON, Ill. (AP) — When bat-mating season coincides with construction season in Illinois, the bats win.

The Rockford Register Star reports that the expansion of Illinois Route 2 from two to four lanes in northwestern Illinois is being delayed by amorous bats.

The $5.8 million project was supposed to get underway this spring, but bats mate in some of the almost 12 acres of trees that will be cleared to make way for the project.

Brown bats are a protected species in Illinois, and mate throughout the spring, summer an early fall. Their population has been reduced by a fast-spreading, lethal disease called white-nose syndrome.

State highway engineers expect the project to resume this fall. They say the expansion is needed to reduce congestion and accidents.

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