Intrinsic and environmental drivers of pairwise cohesion in wild Canis social groups
Authors: Benson John F. , Keiter David A. , Mahoney Peter J. , Allen Benjamin L. , Allen Lee , Álvares Francisco , Anderson Morgan L. , Barber‐Meyer Shannon M. , Barocas Adi , Beasley James C. , Behrendorff Linda , Belant Jerrold L. , Beyer Dean E. , Boitani Luigi , Borg Bridget L. , Boutin Stan , Boydston Erin E. , Brown Justin L. , Bump Joseph K. , Cepek Jonathon D. , Chamberlain Michael J. , Chenaux‐Ibrahim Yvette M. , Cherry Seth G. , Ćirović Duško , Ciucci Paolo , Cluff H. Dean , Cooper Susan M. , Crooks Kevin R. , Dupont Daniel L. J. , Fisher Robert N. , Fortin Daniel , Gable Thomas D. , García Emilio , Geffen Eli , Gehrt Stanley D. , Gillingham Michael , Heard Douglas C. , Hebblewhite Mark , Hinton Joseph W. , Homkes Austin T. , Howden Chris G. , Huber Djuro , Jackson Pat J. , Joly Kyle , Kelly Allicia , Kelly Marcella J. , Kingdon Katrien A. , Kulkarni Abhijeet , Kusak Josip , Kuzyk Gerald W. , Lake Bryce C. , Llaneza Luis , López‐Bao José Vicente , MacNulty Daniel R. , McLaren Ashley A. D. , McLoughlin Philip D. , Merrill Evelyn H. , Mills Kenneth J. , Mitchell Numi , Moore Seth A. , Mumma Matthew A. , Murray Maureen H. , Musiani Marco , Nakamura Mónia , Neilson Eric W. , Neufeld Lalenia M. , Newsome Thomas M. , Oakleaf John K. , Palacios Vicente , Perdicas Marlo M. , Perry Thomas , Petroelje Tyler R. , Piper Cyrenea B. , Prokopenko Christina M. , Prugh Laura R. , Riley Seth P. D. , Rio‐Maior Helena , Roffler Gretchen H. , Rollins Dale , Sand Håkan , Schmiegelow Fiona K. A. , Seip Dale R. , Sorum Mathew S. , St. Clair Colleen C. , Steenweg Robin , Strohbach Michael W. , Tatler Jack , Thaker Maria , Thompson Connor A. , Turner Julie W. , Vanak Abi T. , Vander Wal Eric , Wabakken Petter , Walter Scott E. , Webster Sarah C. , Wheeldon Tyler J. , Wikenros Camilla , Windels Steve K. , Young Julie K. , Zabihi‐Seissan Sana , Zimmermann Barbara , Patterson Brent R. 
Published: December 2024

Animals within social groups respond to costs and benefits of sociality by adjusting the proportion of time they spend in close proximity to other individuals in the group (cohesion). Variation in cohesion between individuals, in turn, shapes important group‐level processes such as subgroup formation and fission–fusion dynamics. Although critical to animal sociality, a comprehensive understanding of the factors influencing cohesion remains a gap in our knowledge of cooperative behavior in animals. We tracked 574 individuals from six species within the genus Canis in 15 countries on four continents with GPS telemetry to estimate the time that pairs of individuals within social groups spent in close proximity and test hypotheses regarding drivers of cohesion. Pairs of social canids (Canis spp.) varied widely in the proportion of time they spent together (5%–100%) during seasonal monitoring periods relative to both intrinsic characteristics and environmental conditions. The majority of our data came from three species of wolves (gray wolves, eastern wolves, and red wolves) and coyotes. For these species, cohesion within social groups was greatest between breeding pairs and varied seasonally as the nature of cooperative activities changed relative to annual life history patterns. Across species, wolves were more cohesive than coyotes. For wolves, pairs were less cohesive in larger groups, and when suitable, small prey was present reflecting the constraints of food resources and intragroup competition on social associations. Pair cohesion in wolves declined with increased anthropogenic modification of the landscape and greater climatic variability, underscoring challenges for conserving social top predators in a changing world. We show that pairwise cohesion in social groups varies strongly both within and across Canis species, as individuals respond to changing ecological context defined by resources, competition, and anthropogenic disturbance. Our work highlights that cohesion is a highly plastic component of animal sociality that holds significant promise for elucidating ecological and evolutionary mechanisms underlying cooperative behavior.