Multiple routes to territory inheritance in Florida Scrub-Jays (Aphelocoma coerulescens)

In many animals, being the dominant owner of a territory is a pre-requisite for reproductive success. Acquisition of territory by inheritance, where at least a portion of the new (breeding) territory is acquired from the natal territory, characterizes many social animals and offers multiple benefits over dispersing away from natal ground. Territory dynamics change rapidly and are difficult to objectively quantify. Additionally, little is known regarding the non-dispersive sex's potential to inherit. We spatially analysed decades of territory maps to identify all nontrivial instances of natal territory inheritance in first-time breeding Florida Scrub-Jays (Aphelocoma coerulescens) and compared initial reproductive success of those that gained breeding status through any form of inheritance versus by other means. Among inheritors, we studied how first-time territory acquisition strategies differed between the sexes. Between 1982 and 2024, 139 out of 1014 first-time breeders gained significant natal territory through inheriting the entire natal territory upon the death of both parents, pairing with an adjacent, widowed neighbour and incorporating some natal ground, or pairing with a novice disperser and budding off of their natal territory (or some combination of two). Among all breeders that inherited substantial portions of natal territory, males did so about twice as often as females (97 vs. 42 instances, respectively). Birds that inherited natal territory did not have higher initial reproductive success than those that did not inherit. Comparing reproduction among birds who inherited, males and females did not differ either. Proportions of territory gained from the natal territory differed markedly between the sexes. Males gained a significantly higher percentage of their natal territory than females, and inherited territory made up a greater portion of their new territories. Males and females took different routes to inheritance: females showed higher plasticity in their acquisition strategy and more frequently paired with neighbouring, experienced widows on large territories, while males more commonly established new, relatively small territories with dispersing, novice females. Our study demonstrates the value in objectively quantifying field-gathered spatial data, as it revealed a previously unidentified trend of opportunistic female dispersals with beneficial fitness consequences.