Behaviors associated with vocal communication of squirrels

Abstract

Vocal communication is an important method squirrels (Sciuridae) use to transfer information from one individual to others. While behaviors associated with vocal communication have been explored in individual species or single call-types in specific groups of squirrels, no comprehensive review of these behaviors exists for Sciuridae. Herein, I review the current literature to describe behaviors associated with vocal communication in three groups of squirrels: ground squirrels, tree squirrels, and flying squirrels. I discuss the behavioral functions of squirrel vocalizations. A wide variety of behaviors are associated with particular call-types produced by squirrels, including alarm, agonistic, discomfort, affiliative, mating, and neonatal calls. There are large knowledge gaps in cataloging the vocal repertoires and associated behaviors of many species of squirrels, including commonly studied species such as marmots and ground squirrels, as alarm calls are typically focused on and other call-types are understudied or ignored. Since vocal communication is important to the development, reproduction, and survival of squirrels, further understanding the biological and ecological drivers behind vocal repertoires is critical to evaluating the ethology of this family as a whole.

Anthropogenically-induced range expansion as an invasion front in native species: An example in North American flying squirrels

“…The geographic range of northern flying squirrels (Glaucomys sabrinus) and southern flying squirrels (Glaucomys volans) in North America. 10.3389/fevo.2023.1096244 Frontiers in Ecology and Evolution 03 frontiersin.org (Stihler et al, 1987;Layne and Raymond, 1994;Reynolds et al, 2009), and large vocal repertoires for intraspecific communication, including alarm and mating calls (Gilley et al, 2019;Diggins, 2021). Denning aggregations can occur year-round (Reynolds et al, 2009;Diggins and Ford, 2021;Doty et al, 2022), but aggregation size typically increases in winter to reduce thermoregulatory costs associated with colder months of the year (Muul, 1968;Stapp et al, 1991;Thorington et al, 2010).…”

Response of the weeping lizard to distress calls: the effect of witnessing predation

“…Conspecifics may react to these calls with antipredator responses, such as the increased vigilance showed by the chipmunk Tamias striatus (Baack and Switzer 2000 ) or the longer inactive period exhibited by the warbler Dendroica petechia (Gill and Sealy 2003 ). In addition, responses can be accurate because calls can provide information, for example, on the type of predator (e.g., aerial, terrestrial; Rendall et al 2009 ; Suzuki 2015 ; Diggins 2021 ) or risk level (e.g., predator proximity; Dutour et al 2021 ; Elgar and Riehl 2021 ). Moreover, because call emission usually is accompanied by information from other sensory channels (e.g., prey visual displays; McRae and Green 2014 ), multisensory information may improve risk assessment (Kavaliers and Choleris 2001 ; Lima and Steury 2005 ; Munoz and Blumstein 2012 ).…”

Structure and Function of the Vocalization of Japanese Squirrels, Sciurus lis

“…Habitat variation also leads to differences in resource availability and, in turn, differ-ences in social systems and communication (Waterman et al 2021). Vocal repertoires have been described in the literature in 85% of 115 species of ground squirrels, 54% of 128 species of tree squirrels, and 36% of 53 species of flying squirrels (Diggins 2021). It has been pointed out that much of the research on squirrel vocalizations relates to alarm calls in ground squirrels and that there is still a significant knowledge gap in understanding the whole picture of squirrels adapted to diverse environments (Newar and Bowman 2020;Diggins 2021).…”

“…There have also been few studies on mammalian vocalizations, except for Chiroptera, Cetacea, and Primates, that have received more attention (Boughman and Moss 2003). Vocalizations in some species of the family Sciuridae have been relatively well studied, and a comprehensive review of the published literature over the past 50 years has been compiled (McRae 2020; Newar and Bowman 2020; Diggins 2021). Sciuridae includes 296 species in 58 genera distributed in all zoogeographical regions, except for the Australian region (Wilson and Reeder 2005; Thorington et al 2012).…”

“…First, we recorded vocalizations made by Japanese squirrels in the field and classified them based on their acoustic characteristics and the squirrel's behavior associated with them (Emmons 1978; Newar and Bowman 2020; Diggins 2021). Next, we conducted a playback experiment in the field and observed the squirrel to determine whether alarm calls with different acoustic structures elicit different antipredator responses.…”