Abstract: The non-breeding period plays a major role in seabird survival and population dynamics. However, our understanding of the migratory behaviour, moulting and feeding strategies of non-breeding seabirds is still very limited, especially for small-sized species. The present study investigated the post-breeding behaviour of three distant populations (Kerguelen Archipelago, southeastern Australia, New Zealand) of the common diving petrel (CDP) (Pelecanoides urinatrix), an abundant, widely distributed zooplanktivorous seabird breeding throughout the southern Atlantic, Indian and Pacific oceans. The timing, geographical destination and activity pattern of birds were quantified through geolocator deployments during the post-breeding migration, while moult pattern of body feathers was investigated using stable isotope analysis. Despite the high energetic cost of flapping flight, all the individuals quickly travelled long distances (greater than approx. 2500 km) after the end of the breeding season, targeting oceanic frontal systems. The three populations, however, clearly diverged spatially (migration pathways and destinations), and temporally (timing and duration) in their post-breeding movements, as well as in their period of moult. Philopatry to distantly separated breeding grounds, different breeding phenologies and distinct post-breeding destinations suggest that the CDP populations have a high potential for isolation, and hence, speciation. These results contribute to improving knowledge of ecological divergence and evolution between populations, and inform the challenges of conserving migratory species.

Abstract: Because Telomere Length (Tl) And Dynamics Relate To Growth, Reproductive Investment And Survival, Telomeres Might Be Markers Of Individual Quality. In The King Penguin, We Tested The Hypothesis That Parental Tl Can Be A Marker Of Parental Quality. We Swapped The Egg Of Breeding Pairs To Disentangle The Contribution Of Pre And/or Post -Laying Parental Quality On Chick’s Growth, Tl And Survival. Parental Quality Was Estimated Through The Effects Of Biological And Foster Parent Tl On Offspring Traits, 10 Or 105 Days After Hatching. We Show That Chick Survival Up To 10 Days Was Negatively Related To Biological Fathers’ Tl Whereas Survival Up To 105 Days Was Positively Related To Foster Fathers’ Tl. Chick Growth Was Not Related To Parents’ Tl. Chick Tl Was Positively Related To Foster Mothers’ Tl At Both 10 And 105 Days. Overall, We Show That, In A Species With Bi-parental Care, Parents’ Tl Is Foremost A Proxy Of Parental Care Quality, Supporting The Telomere &Ndash; Parental Quality Hypothesis.