title: Consequences of narrow temperature tolerance for a pinyon pine sawfly, Neodiprion edulicolus.
abstract: Temperate insect species are predicted to fare better in the face of climate change, because of their wider temperature tolerance, than are tropical species. Predictions are less certain, however, for temperate species with narrow temperature optima. Larvae of the sawfly Neodiprion  edulicolus Ross are susceptible to cold weather and rarely occur above 1,900 m elevation near Sunset Crater, AZ, even though their host trees (Pinus edulis Englemann) are abundant up to 2,300 m. During 12 yr of monitoring, the population of sawflies below 1,850 m declined significantly in  years when April minimum temperatures were either unusually low or unusually high. Sawfly larvae transferred to host trees above 1,900 m were unable to sustain populations despite abundant host trees and high survival of transferred larvae. Cold temperatures delayed and thereby disrupted the  sawfly life cycle. Overall, limited temperature tolerance of N. edulicolus larvae was the most likely cause of the decline of this sawfly population between 1994 and 2006. If April minimum temperatures continue to rise on average and interannual variation remains the same, the frequency of  suboptimal high temperatures will increase. Soon, N. edulicolus, along with other species with narrow temperature optima, may be forced to disperse, adapt exceptionally quickly, or face extinction.
authors.affiliation: osholes@assumption.edu
authors.forename: Owen D V
authors.initials: OD
authors.lastname: Sholes
mesh_terms: D000531:Altitude; D000818:Animals; D057231:Climate Change; D005260:Female; D006927:Hymenoptera / Q000502:physiology*; D008297:Male; D011157:Population Dynamics; D013696:Temperature