Effects of natal habitat preference induction on juvenile loon movements

NHPI develops in natural systems. Here, we tested for NHPI in juvenile
common loons (Gavia immer) that foraged on lakes in the vicinity of their
natal lake after fledging. Juveniles visited lakes similar in pH to their
natal lakes, and this significant effect persisted after controlling for
spatial autocorrelation. On the other hand, juveniles showed no preference
for foraging lakes of similar size to their natal one. When lakes were
assigned to discrete classes based on size, depth, visibility, and trophic
complexity, both juveniles from large lakes and small lakes preferred to
visit large, trophically diverse lakes, which contained abundant food. Our
results contrast with earlier findings, which show strict preference for
lakes similar in size to the natal lake among young adults seeking to
settle on a breeding lake. We suggest that NHPI is relaxed for juveniles,
presumably because they select lakes that optimize short-term survival and
growth. By characterizing NHPI during a poorly-studied life-stage, this
study illustrates that NHPI can take different forms at different life
stages.