Limited dispersal by large juvenile males leads to kin-structured neighborhoods in the black-crested titmouse (Baeolophus atricristatus)

• Published in: Behavioral ecology and sociobiology Vol. 74; no. 6; pp. 1 - 9
• Main Authors: Rylander, Rebekah J., Fritts, Sarah R., Aspbury, Andrea S.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Science + Business Media 01-06-2020; Springer Berlin Heidelberg; Springer Nature B.V
• Subjects: Aggressive behavior; Animal behavior; Animal Ecology; Baeolophus atricristatus; Behavioral Sciences; Biomedical and Life Sciences; Dispersal; Dispersion; Energy conservation; Fitness; Foraging habitats; Gene flow; Home range; Juveniles; Life Sciences; Males; ORIGINAL ARTICLE; Philopatry; Populations; Woodlands; Zoology; United States > US; Texas; Black-crested titmouse; Familial flocking; Limited dispersal; Kin-structured neighborhood
• ISSN: 0340-5443; 1432-0762
• DOI: 10.1007/s00265-020-02844-x

Dispersal of young from natal home ranges can result in gene flow and increased variation within populations. However, juveniles that remain near kin and form familial groups can accrue indirect fitness benefits. Between 2013 and 2015, we studied families (n = 34) of black-crested titmice (Baeolophus atricristatus) in central Texas to assess factors affecting juvenile dispersal. Our results suggest that males of greater mass relative to siblings tended to be more philopatric than smaller males or females of any size. Dispersal of juveniles was not affected by home range size of the territorial male, habitat composition of the home range (percent woodland cover), or date in which young fledged the nest. Interactions between neighboring groups of related titmice were more tolerant than interactions between unrelated groups. In most cases, retained male juveniles established territories adjacent to their natal home range, likely increasing their fitness by saving energy through tolerant interactions with kin.