The ecology and niche segregation of diving petrels

• Main Author: Fromant, Aymeric
• Other Authors: Université de La Rochelle, Deakin university (Geelong, Australie), John Arnould, Charles-André Bost
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: HAL CCSD 2022
• Subjects: Foraging ecology; Behavioural ecology; Ecological niche; Tracking; Stable isotope analysis; Procellariiforme; Pelecanoides; P. urinatrix; P. georgicus; Écologie alimentaire; Écologie comportementale; Niche écologique; Analyse des isotope stables; [SDV.SA]Life Sciences [q-bio]/Agricultural sciences; [SDV.BA]Life Sciences [q-bio]/Animal biology; Southern Ocean; Pétrels
• Online Access: https://theses.hal.science/tel-03959129; https://theses.hal.science/tel-03959129/document; https://theses.hal.science/tel-03959129/file/2022FROMANT192148.pdf

Exploring a species’ ecological niche entails investigating at multiple scales, as different environmental threats and niche constraints between intra-species levels may lead to important ecological and conservation consequences. However, the absence of precise information about small procellariiform species ecology has greatly limited ecological niche modelling studies, directly impacting our ability to delineate proper conservation planning. Technological advancements in the miniaturisation of data loggers have made it possible to collect ecological data of such species. In the present study, a multi-tooled approach was used to investigate the ecological niche of the common and the South-Georgian diving petrels. The primary objectives were to: 1) describe their foraging ecology during the breeding and non-breeding periods, and investigate their inter-annual variations; 2) determine the ecological differences between populations throughout the Southern Ocean; and 3) study the variations in their foraging ecology throughout the entire annual-cycle in the context of niche segregation between two sibling species. The results demonstrated that diving petrels exhibit remarkable flying abilities despite their high wing loading, foraging over large areas during the breeding season, and migrating several thousands of kilometres from their colony during the post-breeding period. These analyses revealed important ecological differences throughout the species distribution, particularly in terms of phenology and migration area. Collecting data over several years substantially strengthens results and provides valuable information to understand the variations and the limits of diving petrel ecological niches. Finally, a stage-dependent and context-dependent niche segregation analysis demonstrated the importance of a multi-tooled approach to better describe and understand the co-existence of ecologically similar species. L'exploration de la niche écologique d'une espèce implique une analyse à plusieurs échelles, car ...