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Full-Text Articles in Marine Biology
Favorable Spring Conditions Can Buffer The Impact Of Winter Carryover Effects On A Key Breeding Decision In An Arctic-Breeding Seabird, Rolanda J. Steenweg, Glenn T. Crossin, Holly L. Hennin, H. Grant Gilchrist, Oliver P. Love
Favorable Spring Conditions Can Buffer The Impact Of Winter Carryover Effects On A Key Breeding Decision In An Arctic-Breeding Seabird, Rolanda J. Steenweg, Glenn T. Crossin, Holly L. Hennin, H. Grant Gilchrist, Oliver P. Love
Great Lakes Institute for Environmental Research Publications
The availability and investment of energy among successive life-history stages is a key feature of carryover effects. In migratory organisms, examining how both winter and spring experiences carryover to affect breeding activity is difficult due to the challenges in tracking individuals through these periods without impacting their behavior, thereby biasing results. Using common eiders Somateria mollissima, we examined whether spring conditions at an Arctic breeding colony (East Bay Island, Nunavut, Canada) can buffer the impacts of winter temperatures on body mass and breeding decisions in birds that winter at different locations (Nuuk and Disko Bay, Greenland, and Newfoundland, Canada; assessed …
Baseline Corticosterone Does Not Reflect Iridescent Plumage Traits In Female Tree Swallows, Keneth Sarpong, Christine L. Madliger, Christopher M. Harris, Oliver P. Love, Stéphanie M. Doucet, Pierre Paul Bitton
Baseline Corticosterone Does Not Reflect Iridescent Plumage Traits In Female Tree Swallows, Keneth Sarpong, Christine L. Madliger, Christopher M. Harris, Oliver P. Love, Stéphanie M. Doucet, Pierre Paul Bitton
Great Lakes Institute for Environmental Research Publications
The production of high quality secondary sexual traits can be constrained by trade-offs in the allocation of energy and nutrients with other metabolic activities, and is mediated by physiological processes. In birds, the factors influencing male plumage quality have been well studied; however, factors affecting female plumage quality are poorly understood. Furthermore, it remains uncertain which physiological traits mediate the relationship between body condition and ornaments. In this three-year study of after-second-year female tree swallows (Tachycineta bicolor), we investigated (1) the relationship between baseline corticosterone near the end of the brood-rearing period (CORTBR) and feather colour characteristics (hue, saturation, brightness) …
Employing Individual Measures Of Baseline Glucocorticoids As Population-Level Conservation Biomarkers: Considering Within-Individual Variation In A Breeding Passerine, Christine L. Madliger, Oliver P. Love
Employing Individual Measures Of Baseline Glucocorticoids As Population-Level Conservation Biomarkers: Considering Within-Individual Variation In A Breeding Passerine, Christine L. Madliger, Oliver P. Love
Great Lakes Institute for Environmental Research Publications
Labile physiological variables, such as stress hormones [i.e. glucocorticoids (GCs)], allow individuals to react to perturbations in their environment and may therefore reflect the effect of disturbances or positive conservation initiatives in advance of population-level demographic measures. Although the application of GCs as conservation biomarkers has been of extensive interest, few studies have explicitly investigated whether baseline GC concentrations respond to disturbances consistently across individuals. However, confirmation of consistent responses is of paramount importance to assessing the ease of use of GCs in natural systems and to making valid interpretations regarding population-level change (or lack of change) in GC concentrations. …
Temporal Overlap And Repeatability Of Feather Corticosterone Levels: Practical Considerations For Use As A Biomarker, Christopher M. Harris, Christine L. Madliger, Oliver P. Love
Temporal Overlap And Repeatability Of Feather Corticosterone Levels: Practical Considerations For Use As A Biomarker, Christopher M. Harris, Christine L. Madliger, Oliver P. Love
Great Lakes Institute for Environmental Research Publications
The measurement of corticosterone (CORT) levels in feathers has recently become an appealing tool for the conservation toolbox, potentially providing a non-invasive, integrated measure of stress activity throughout the time of feather growth. However, because the mechanism of CORT deposition, storage and stability in feathers is not fully understood, it is unclear how reliable this measure may be, especially when there is an extended interval between growth and feather collection. We compared CORT levels of naturally grown feathers from tree swallows (Tachycineta bicolor) that were moulted and regrown concurrently and therefore expected to have similar CORT levels. Specifically, we compared …