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Extensive regional variation in the phenology of insects and their response to temperature across North America

Peter Dunn·Insiyaa Ahmed·Elise Armstrong·Natasha Barlow·Malcolm Barnard·Marc Belisle·T.J. Benson·Lisha Berzins·Chloe Boynton·T. Anders Brown·Melissa Cady·Kyle Cameron·Xuan Chen·Bob Clark·Ethan Clotfelter·Kara Cromwell·Russ Dawson·Elsie Denton·Andrew Forbes·Kendrick Fowler·Kamal J.K. Gandhi·Dany Garant·Megan Hiebert·Claire Houchen·Jennifer Houtz·Tara Imlay·Brian Inouye·David Inouye·Michelle Jackson·Andrew Jacobson·Kristen Jayd·Christy Juteau·Andrea Kautz·Caroline Killian·Kimberly J Komatsu·Kirk Larsen·Andrew Laughlin·Valerie Levesque-Beaudin·Ryan Leys·Elizabeth Long·Stephen Lougheed·Stu Mackenzie·Jen Marangelo·Colleen Miller·Brenda Molano-Flores·Christy Morrissey·Emony Nicholls·Jessica Orlofske·Ian S. Pearse·Kristen Peck·Fanie Pelletier·Amber Pitt·Joe Poston·Danielle Racke·Jeannie A. Randall·Matthew Richardson·Olivia Rooney·A. Rose Ruegg·Scott Rush·Sadie J. Ryan·Mitchell Sadowski·Ivana Schoepf·Lindsay Schulz·Brenna Shea·Tom Sheehan·Lynn Siefferman·Derek Sikes·Mark Stanback·Jennifer Styrsky·John Styrsky·Conor Taff·Jennifer Uehling·Kit Uvino·Thomas Wassmer·Katie Weglarz·Megan Weinberger·John Wenzel·Linda A Whittingham
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Abstract

Climate change models often assume similar responses to temperatures across the range of a species, but local adaptation or phenotypic plasticity can lead plants and animals to respond differently to temperature in different parts of their range. To date, there have been few tests of this assumption at the scale of continents, so it is unclear if this is a large-scale problem. Here, we examined the assumption that insect taxa show similar responses to temperature at 96 sites in grassy habitats across North America. We sampled insects with Malaise traps during 2019–2021 ( N = 1041 samples) and examined the biomass of insects in relation to temperature and time of season. Our samples mostly contained Diptera (33%), Lepidoptera (19%), Hymenoptera (18%), and Coleoptera (10%). We found strong regional differences in the phenology of insects and their response to temperature, even within the same taxonomic group, habitat type, and time of season. For example, the biomass of nematoceran flies increased across the season in the central part of the continent, but it only showed a small increase in the Northeast and a seasonal decline in the Southeast and West. At a smaller scale, insect biomass at different traps operating on the same days was correlated up to ~75 km apart. Large-scale geographic and phenological variation in insect biomass and abundance has not been studied well, and it is a major source of controversy in previous analyses of insect declines that have aggregated studies from different locations and time periods. Our study illustrates that large-scale predictions about changes in insect populations, and their causes, will need to incorporate regional and taxonomic differences in the response to temperature.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 17.94655° to 83.23324° latitude; -171.79111° to -52.6481° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Peter Dunn, Insiyaa Ahmed, Elise Armstrong, Natasha Barlow, Malcolm Barnard, Marc Belisle, T.J. Benson, Lisha Berzins, Chloe Boynton, T. Anders Brown, Melissa Cady, Kyle Cameron, Xuan Chen, Bob Clark, Ethan Clotfelter, Kara Cromwell, Russ Dawson, Elsie Denton, Andrew Forbes, Kendrick Fowler, Kamal J.K. Gandhi, Dany Garant, Megan Hiebert, Claire Houchen, Jennifer Houtz, Tara Imlay, Brian Inouye, David Inouye, Michelle Jackson, Andrew Jacobson, Kristen Jayd, Christy Juteau, Andrea Kautz, Caroline Killian, Kimberly J Komatsu, Kirk Larsen, Andrew Laughlin, Valerie Levesque-Beaudin, Ryan Leys, Elizabeth Long, Stephen Lougheed, Stu Mackenzie, Jen Marangelo, Colleen Miller, Brenda Molano-Flores, Christy Morrissey, Emony Nicholls, Jessica Orlofske, Ian S. Pearse, Kristen Peck, Fanie Pelletier, Amber Pitt, Joe Poston, Danielle Racke, Jeannie A. Randall, Matthew Richardson, Olivia Rooney, A. Rose Ruegg, Scott Rush, Sadie J. Ryan, Mitchell Sadowski, Ivana Schoepf, Lindsay Schulz, Brenna Shea, Tom Sheehan, Lynn Siefferman, Derek Sikes, Mark Stanback, Jennifer Styrsky, John Styrsky, Conor Taff, Jennifer Uehling, Kit Uvino, Thomas Wassmer, Katie Weglarz, Megan Weinberger, John Wenzel, Linda A Whittingham. 2023-04-04. Extensive regional variation in the phenology of insects and their response to temperature across North America. https://doi.org/10.1002/ecy.4036

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