Born to be wild: Captive-born and wild Iberian lynx ('Lynx pardinus') reveal space-use similarities when reintroduced for species conservation concerns

Resumen

An ambitious conservation programme to save the Iberian lynx from extinction conducted several reintroductions aiming to restore its historical range. The urgency due to the delicate conservation status prompted translocating captive-born and wild individuals, while preventing an early assessment of how both groups combined their space-use and differed in post-release movements. To address this issue, we conducted a comprehensive movement ecology analysis using GPS data of 161 Iberian lynxes from 9 populations. First, we classified five movement phases within individuals' trajectories: residence areas (stable and transient), excursions, post-release dispersals, and transitions between residences. Second, we used continuous-time movement models to estimate range size and daily speeds and measured the distance travelled during extra-territorial movements. Finally, we conducted comparative analyses to evaluate differences between captive-born, wild translocated, and wild non-translocated individuals across phases, sex, age-class and populations. Most individuals in all groups established home ranges, supporting the reintroduction main goal. Yet, contrary to the species' natural pattern, captive-born subadults did not show intersexual home range size differences, which emerged after experiencing free-ranging, when becoming adults. More differences emerged for non-residential behaviours. Captive-born lynxes were more prone to post-release dispersal, to slower post-release movements and to having smaller transient residences, indicating cautious behaviour. Our study supports using captive-born individuals for reintroductions, while prioritizing wild individuals for reinforcements in highly competitive populations. Further, we suggest relevant metrics for planning translocations and connectivity management, and we demonstrate how an integrated 'ex-situ' and reintroduction initiative can substantially contribute to restoring an endangered species' distribution range.