Plasma mammalian leptin analogue predicts reproductive phenology, but not reproductive output in a capital‐income breeding seaduck

• Published in: Ecology and Evolution
• Main Authors: Hennin, Holly, Legagneux, Pierre, Gilchrist, H. Grant, Bêty, Joël, McMurtry, John, Love, Oliver
• Other Authors: Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre d'Etudes Nordiques et Département de Biologie, Université Laval Québec (ULaval)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2018
• Subjects: clutch size; common eider; energetic demand; leptin; plasma mammalian leptin analogue; reproductive phenology; reproductive success; [SDE]Environmental Sciences; Arctic; Common Eider; Somateria mollissima
• Online Access: https://hal.archives-ouvertes.fr/hal-03025273; https://doi.org/10.1002/ece3.4873

International audience To invest in energetically demanding life history stages, individuals require a substantialamount of resources. Physiological traits, particularly those related to energetics,can be useful for examining variation in life history decisions and trade‐offs becausethey result from individual responses to environmental variation. Leptin is a proteinhormone found in mammals that is proportional to the amount of endogenous fatstores within an individual. Recently, researchers have confirmed that a mammalianleptin analogue (MLA), based on the mammalian sequence of leptin, is present withassociated receptors and proteins in avian species, with an inhibitory effect on foragingand body mass gain at high circulating levels. While MLA has been both quantifiedand manipulated in avian species, little is currently known regarding whetherplasma MLA in wild‐living species and individuals is associated with key reproductivedecisions. We quantified plasma MLA in wild, Arctic‐nesting female common eiders(Somateria mollissima) at arrival on the breeding grounds and followed them to determinesubsequent breeding propensity, and reproductive phenology, investment, andsuccess. Common eiders are capital‐income breeding birds that require the accumulationof substantial fat stores to initiate laying and successfully complete incubation.We found that females with lower plasma MLA initiated breeding earlier and in ashorter period of time. However, we found no links between plasma MLA levels andbreeding propensity, clutch size, or reproductive success. Although little is still knownabout plasma MLA, based on these results and its role in influencing foraging behaviorsand condition gain, plasma MLA appears to be closely linked to reproductivetiming and is therefore likely to underlie trade‐offs surrounding life historydecisions.