ALBANY, N.Y. (AP) — Warmer weather in early spring is spawning more generations of some butterflies in northern climes and scientists are unsure if it will help or hurt the population in the long run.

The federally endangered Karner blue butterfly produced an unprecedented third generation this year in the Albany Pine Bush Preserve, said Neil Gifford, conservation director of the 3,200-acre pine barrens west of New York’s capital.