6 month master project opportunity in Arctic seabird ecotoxicology
Mis à jour : il y a 2 jours
Persistent organic pollutants (POPs) are synthetically manufactured chemicals extensively used during the 20th century in numerous industrial, commercial and agricultural applications. In addition to the numerous synthetic chemicals, other contaminants are naturally present on Earth as is the case for mercury (Hg). However, despite its natural origin, human activities have considerably increased the global amount of Hg cycling around the world. Harmful for living organisms, POPs and Hg are in the spotlight of toxicological studies leading to past and on-going national and international regulations, well-illustrated by the Stockholm Convention adopted in 2001 to protect human health and environment. Despite overall temporal declining trends, the so-called “legacy POPs”, a group of prohibited contaminants, are still present in high concentrations and highly toxic for wildlife.
Due to their high volatility and persistence in time, POPs and Hg reach remote areas such as the Arctic. Once deposited in marine ecosystems, living organisms assimilate these contaminants via food intake. The POPs and Hg concentrations then increase from the marine environment into the organisms and throughout food webs due to bioaccumulation and biomagnification. As long-lived marine predators, Arctic seabirds are exposed to relatively high concentrations of environmental contaminants; they are thus considered as extremely pertinent biological indicators to investigate the potential hazardous effects of environmental contaminants on wildlife. Because of their endocrine and/or metabolic disrupting properties, POPs and Hg may induce physiological stress which, in turn, could alter individual life-history traits and population dynamics.
Telomeres are DNA-protein complexes located at the ends of chromosomes considered as promising molecular proxies of physiological stress in free-living vertebrates. Telomeres are non-coding DNA-protein complexes located at the end of linear eukaryotic chromosomes which play a critical role in maintaining and ensuring the genomic integrity and stability. Because the DNA polymerase protein complex is unable to fully achieve the chromosomes replication during mitosis, telomere length progressively shortens along life. When telomere length reaches a critical lower threshold, cell division can damage coding DNA leading to apoptosis or cellular senescence. Telomere length has been shown to be reliable predictors of longevity and survival rate in wild vertebrates and are thought to reflect individual quality in long lived birds. Their attrition is accelerated by a wide range of environmental stressors and the effects of environmental contaminants on telomere length was until recently almost unexplored for wildlife.
In Svalbard (Norwegian Arctic), black-legged kittiwakes are exposed to a complex cocktail of contaminants including the polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and Hg. Most of studies focused so far on adults during the breeding period while the early-life exposure in chicks has been overlooked. Yet, early-life conditions have long-term fitness consequences.
The aim of this master project is “to investigate the potential physiological stress consequences of contaminant exposure in Svalbard kittiwakes. Contaminants and telomeres length have been measured twice in the same birds, at the chick stage and few years later when recruiting the colony.
The master student will be involved in a multidisciplinary project and should focus on the following topics:
1/ Describe the POPs and Hg profiles of early-life kittiwakes and investigate the temporal dynamic.
2/ Investigate the telomere length dynamic in relation to the contaminant levels.
Fieldwork and lab analyses are already performed which guarantee the student to have valuable data for the master thesis. The student will be involved in paper writing and included as an author in the scientific publications if relevant (key asset to get a PhD grant). The student will be highly encouraged to disseminate the results through oral presentations. This is unfortunately a non-paid internship.
We are looking for an autonomous and highly motivated student able to communicate in English. It is important to have skills in R-software and statistics (e.g. GLM, GLMM…).
If you are interested, please send a CV + motivation letter and references to email@example.com.
The student will be based in Tromsø (Norway), supervised by Pierre Blévin (Researcher at Akvaplan-niva; https://www.pierreblevin.com/) and Børge Moe (Project leader-NINA); and will be in contact all along the project with several international scientists.
For more information about the topic:
Blévin, P., Angelier, F., Tartu, S., Ruault, S., Bustamante, P., Herzke, D., Moe, B., Bech, C., Gabrielsen, G.W., Bustnes, J.O., 2016. Exposure to oxychlordane is associated with shorter telomeres in arctic breeding kittiwakes. Science of the Total Environment 563, 125–130.
Angelier, F., Costantini, D., Blévin, P., Chastel, O., 2017. Do glucocorticoids mediate the link between environmental conditions and telomere dynamics in wild vertebrates? A review. General and Comparative Endocrinology 256, 99–111.
Blévin, P., Angelier, F., Tartu, S., Bustamante, P., Herzke, D., Moe, B., Bech, C., Gabrielsen, G.W., Bustnes, J.O., Chastel, O., 2017. Perfluorinated substances and telomeres in an Arctic seabird: Cross-sectional and longitudinal approaches. Environmental Pollution 230, 360–367.
Sebastiano, M., Angelier, F., Blévin, P., Ribout, C., Sagerup, K., Descamps, S., Herzke, D., Barbraud, C., Bustnes, J.O., Gabrielsen, G.W., Chastel, O. Exposure to PFAS is associated with telomere length dynamics and demographic responses of an arctic top predator. Environmental Science & Technology 54, 16, 10217–10226.