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. Certain species form family groups that provide additional fitness benefits to related individuals. However, not all kin-structured organisms respond to the same factors that enable the persistence of family-dominated populations. We examined factors that could influence the limited dispersal behavior of the black-crested titmouse, Baeolophus atricristatus, in central Texas. Limited dispersal occurs when a juvenile disperses a short distance (< 400 m) and establishes a territory adjacent to its natal home range the following year. In the black-crested titmouse, sex and mass of juveniles greatly influence limiting dispersing individuals, typically with the heaviest male juveniles exhibiting philopatry. Thus, overtime, kin-structured neighborhoods develop, allowing related family groups to spare energetically taxing aggressive behaviors and instead forage passively near one another.

中文翻译：

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大型幼年雄性的有限扩散导致黑冠山雀（Baeolophus atricristatus）中的亲属结构社区

从出生家庭范围内分散幼崽会导致基因流动和种群内变异的增加。然而，保持近亲并形成家庭群体的少年可以产生间接的健康益处。2013 年至 2015 年期间，我们研究了德克萨斯州中部的黑冠山雀 (Baeolophus atricrstatus) 的家族 (n = 34)，以评估影响幼鸟传播的因素。我们的结果表明，与兄弟姐妹相比，体重较大的雄性往往比体型较小的雄性或雌性更亲近。幼鱼的扩散不受领地雄性的家庭范围大小、家庭范围的栖息地组成（林地覆盖百分比）或幼鸟成巢日期的影响。相关山雀的相邻群体之间的相互作用比不相关群体之间的相互作用更宽容。在大多数情况下，保留下来的雄性幼鱼在其出生地附近建立了领土，可能通过与亲属的宽容互动来节省能量来提高他们的健康度。某些物种形成家庭群体，为相关个体提供额外的健康益处。然而，并非所有具有亲属结构的生物都对相同的因素做出反应，这些因素使家庭主导的种群能够持续存在。我们研究了可能影响德克萨斯州中部黑冠山雀 Baeolophus atricristatus 有限扩散行为的因素。当幼鱼在短距离（< 400 m）中分散并在第二年在其出生地附近建立领土时，就会发生有限的分散。在黑冠山雀中，幼体的性别和数量极大地影响了限制分散的个体，通常与最重的雄性幼鱼表现出亲情。因此，随着时间的推移，亲属结构的社区发展起来，允许相关的家庭群体避免积极征税的侵略行为，而是被动地彼此靠近。