Kinship and social structure of bobcats (Lynx rufus) inferred from microsatellite and radio-telemetry data J. E. Janec ˇka 1 , T. L. Blankenship 2 , D. H. Hirth 1 , M. E. Tewes 3 , C. W. Kilpatrick 4 & L. I. Grassman Jr 3 1 Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, VT, USA 2 Rob and Bessie Welder Wildlife Foundation, Sinton, TX, USA 3 Caesar Kleberg Wildlife Research Institute, Texas A&M University-Kingsville, Kingsville, TX, USA 4 Department of Biology, University of Vermont, Burlington, VT, USA Keywords bobcat; kinship; Lynx rufus; microsatellite DNA; radio-telemetry; social structure. Correspondence Jan E. Janec ˇ ka. Current address: Caesar Kleberg Wildlife Research Institute, Texas A&M University-Kingsville, 700 University Boulevard, MSC 218, Kingsville, TX 78363, USA. Email: jjanecka@neo.tamu.edu Received 8 June 2005; accepted 26 October 2005 doi:10.1111/j.1469-7998.2006.00099.x Abstract Kinship analysis using 12 microsatellites was compared with radio-telemetry data to examine the social structure of bobcats Lynx rufus in southern Texas. Genetically identified kinship relationships combined with capture data were used to reconstruct pedigrees. Three family groups were constructed from parent/ offspring pairs identified from shared alleles. All parents identified by genetic analysis had established home ranges. Individuals with no distinct home ranges were not genetically observed to have offspring among the bobcats sampled. This suggests that establishing a home range is necessary for bobcats to breed. Of three identified male offspring and three identified female offspring, two female off- spring were philopatric. These females became a part of the breeding population in their natal area. Among sibling pairs that included nine female and four male individuals, four females and one male were residents suggesting male-biased dispersal. Introduction Relationships between individual animals are important in explaining the behavior and social structure in groups (Ralls et al., 2001). Individuals that are closely related may benefit indirectly from the fitness of their relatives through inclusive fitness (Hamilton, 1976a, b). Kin-selected behavior may evolve when relatives are in close proximity because they have an influence on each other’s fitness (Ralls et al., 2001). Kinship may explain patterns within a society and the structure of groups (Gompper, Gittleman & Wayne, 1998). Relatedness often has a large influence on social structure by influencing territoriality, social behavior, tolerance and dispersal (Gompper et al., 1998). At a broader scale, the genetic and geographic structure of a population is influ- enced by the social dynamics between related and unrelated individuals (Sugg et al., 1996). There are two alternative social structure strategies in felids (Poole, 1985; Packer, 1986). Lions Panthera leo are highly social, and cheetah Acinonyx jubatus and domestic cat Felis catus also exhibit social behavior to a lesser degree; however, all other felid species appear to be solitary and exhibit similar social organization (Packer, 1986; Caro, 1994, Liberg et al., 2000). Bobcats Lynx rufus have solitary behavior typical of felids (McCord & Cardoza, 1982; Pack- er, 1986). Females have home ranges that generally do not overlap with those of other females, but may overlap with those of males (McCord & Cardoza, 1982). By contrast, male home ranges may have significant intra- and inter- sexual overlap (Lariviere & Walton, 1997), and are typically larger than female home ranges (Kitchings & Story, 1984). Residents use visual and olfactory signs to maintain their home ranges via mutual avoidance (Anderson, 1988; Lari- viere & Walton, 1997). Transient individuals do not have established home ranges and often use sub-optimal habitat (McCord & Cardoza, 1982). When a resident is removed, neighbors adjust their home ranges accordingly or a tran- sient fills the new vacancy (McCord & Cardoza, 1982; Anderson, 1988; Lariviere & Walton, 1997). Conversely, several researchers have observed home- range patterns in bobcats inconsistent with typical felid social structure. In several studies home ranges and core areas of two females nearly completely overlapped (Kitch- ings & Story, 1984; Chamberlain, Leopold & Conner, 2003). These discrepancies were explained by possible relationships between the females; however, no data on relatedness were available. Parent/offspring relationships between females may explain overlapping home ranges and core areas. A bobcat may recognize the home range of a first-order relative (parent/offspring or full sibling) from visual and olfactory signs (Lariviere & Walton, 1997). On the basis of kin-selection theory, an individual may be more tolerant of competition from a relative than from an unrelated indivi- dual (Wade & Breden, 1987). Therefore, in some cases bobcats may prove to exhibit territorial tolerance towards close kin. However, the correlation between intra-sexual Journal of Zoology 269 (2006) 494–501 c  2006 The Authors. Journal compilation c  2006 The Zoological Society of London 494 Journal of Zoology. Print ISSN 0952-8369