Multi-year assessment of variability in spatial and social relationships in a subterranean rodent, the highland tuco‑tuco (Ctenomys opimus)

O'BRIEN, SHANNON L; TAMMONE, MAURO N; CUELLO, PABLO A; LACEY, EILEEN A

BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY

SPRINGER

Año: 2021

0340-5443

In some species, populations routinely contain a mixture of lone and group-living individuals. Such facultative sociality mayreflect individual differences in behavior as well as adaptive responses to variation in local environmental conditions. To exploreinteractions between individual- and population-level variabilities in behavior in a species provisionally described as facultativelysocial, we examined spatial and social relationships within a population of highland tuco-tucos (Ctenomys opimus) at Laguna delos Pozuelos, Jujuy Province, Argentina. Using data collected over 5 consecutive years, we sought to (1) confirm the regular occurrenceof both lone and group-living individuals and (2) characterize the temporal consistency of individual social relationships. Ouranalyses revealed that although the study population typically contained lone as well as group-living animals, individual spatial andsocial relationships varied markedly over time. Specifically, the extent to which individuals remained resident in the same locationacross years varied, as did the number of conspecifics with which an animal lived, with an overall tendency for individuals to livein larger groups over successive years. Collectively, these analyses indicate that population-level patterns of behavior in C. opimusare consistent with facultative sociality but that this variation does not arise due to persistent differences in individual behavior(i.e., living alone versus with conspecifics). Instead, based on changes in spatial and social relationships across years, we suggestthat variation in the tendency to live in groups is shaped primarily by local ecological and demographic conditions.