Spatial clustering of nests of related individuals may arise from elevated local relatedness due to limited dispersal. Natal philopatry can lead to spatial genetic structuring in nesting bird populations (Scribner et al. 2001, van Dijk et al. 2014, Leedale et al. 2018), and which in turn can affect aspects of sociality and reproductive strategies (Hamilton 1964, Andersson 1984, 2018, Riehl 2017).