We discuss periodical cicada (Magicicada) Brood VII, which is becoming extinct from much of its historically-reported range in upstate New York. During searches in June of 2001, we found Magicicada adults in only 10 of 37 sites (and two of eight counties) where periodical cicadas had been reported previously, and dense populations were restricted to a small region south of Syracuse and centered on the Onondaga Nation. We suggest possible explanations, including land clearing and climate change, for the decline of this brood and the extinction of other Magicicada broods.