Des Ursulines Building
300 Allée des Ursulines
Arctic temperatures are increasing twice as fast than the global average (1). Those changes modify the properties of the cryosphere (i.e. ice cover of terrestrial system) by decreasing its surface, its thickness and its time of occurrence (2). This process is known to modify the biogeochemical cycles and the trophic relationships, affecting marine biodiversity habitats (3). The increase of temperatures also promotes melting of tidewater glaciers, bringing a significant amount of freshwater discharge in the sea (i.e. calving front). These discharges promote the rise of upwelling plumes, carrying plankton to the surface. Due to the increased accessibility of preys, these calving fronts constitute an important feeding area for arctic vertebrates such as the black-legged kittiwake (Rissa tridactyla) (3). The black-legged kittiwake is a high-level trophic predator with a circumpolar distribution. This trophic position makes it sensitive to environmental changes and researchers frequently used it as bioindicator of oceanic temperature variations and food abundance (4). The Intergovernmental Panel on Climate Change predicts that the Arctic would be ice-free during summers by 2050 (5), underlining the importance of understanding how these changes would affect feeding and reproductive strategies of seabird communities.
This study aims to investigate whether tidewater glacier front is representing a high-quality foraging zone for arctic seabird populations, promoting the maintenance of high reproductive success and viable population size, despite the global sea warming and consequent changes on trophic relationships. From this general statement, three hypotheses will be tested;
Hypothesis 1: Black-legged kittiwake populations are using tidewater glacier fronts as feeding zone under reproductive period;
Hypothesis 2: Individuals using tidewater glacier calving fronts demonstrate a higher reproductive success than those that are not feeding at these zones;
Hypothesis 3: The productivity of the colonies that are using tidewater glacier fronts is sufficient to compensate population annual mortality.
Black-legged kittiwakes are known to have variable feeding strategies across the breeding season, where longest distances are usually travelled during incubation period and shortest during the chick-rearing one (6). By camera monitoring, we will investigate the temporal variation in the use of calving fronts as feeding zones across the breeding period. Along phenology, evidences suggest that feeding strategies in seabirds also varies according to sexes (7), with males travelling further than females. In order to determine the level of spatiotemporal variability among individuals and colonies, as well as by sex, fine-scale movement analysis will be achieved by monitoring the pattern of 40 individuals fitted with GPS per colony (six colonies in total). Combining telemetry and reproductive success data, we aim to understand the potential selective advantage associated with the use of tidewater glacier front. The analysis will be realized at two levels, at the individual and colony level, correlating movement patterns to their relative breeding outputs. Finally, we aim to understand and predict the effect of glacier fronts on seabird population demography. Empirical demographic data will be used in different theoretical scenarios to explore the effect of glacier fronts on population trajectories.
Significance of the project
The project results will improve our understanding of the importance of glacier fronts in Arctic landscape, and their effect on reproductive performances of seabird communities. This knowledge is key for the elaboration of future management plans necessary to arctic seabird conservation.
(1) Blunden et al. 2012. Bull. Amer. Meteor. Soc. 93:S1–S264. (2) Vihma. 2014. Surv. Geophys. 35:1175-1214. (3) Grémillet et al. 2015. Glob. Chang. Biol. 21:1116-1123. (4) Frederiksen et al. 2007. Mar. Ecol. Prog. Ser. 350:137-143. (5) IPCC. 2014. Climate Change 2014: Synthesis Report. Geneva. (6) Robertson et al. 2014. Mar. Biol. 161:1973-1986. (7) Pinet et al. 2012. Anim. Behav. 83:979-989.
Bertrand, P., Bowman, J., Dyer, R.J., Manseau, M., Wilson, P.J., 2017. Sex‐specific graphs: Relating group‐specific topology to demographic and landscape data. Molecular Ecology, 26(15): 3898-3912. DOI: 10.1111/mec.14174.
Haché, S., Bertrand, P., Fiola, M.-L., Thériault, S., Bayne, E., Villard, M.-A., 2016. Band-related foot loss does not prevent successful return and reproduction in the ovenbird (Seiurus aurocapilla). Wilson Journal of Ornithology, 128(4): 913-918. DOI: 10.1676/15-172.1.
Boulanger, Y., Arseneault, D., Morin, H., Jardon, Y., Bertrand, P., Dagneau, C., 2012. Dendrochronological reconstruction of spruce budworm (Choristoneura fumiferana) outbreaks in southern Quebec for the last 400 years. Canadian Journal of Forest Research, 42: 1264-1276.