There are large pristine areas in the Arctic with important populations of birds and mammals sensitive to human disturbance. Revegetation of disturbed habitats and degradation of pollutants are generally slow due to low temperatures and seasonal darkness. High concentrations of contaminants accumulate in top predators with potential implications for human health. These are aspects contributing to the picture of a fragile Arctic environment. However, there are also elements of robustness in the Arctic Ecosystems, some related to the adaptation of animals and plants to large seasonal and inter-annual variations in environmental conditions and some related to habitat dynamics caused by the forces of ice and snow. In this workshop we will focus on aspects of fragility and robustness of Arctic ecosystems and populations, and discuss the pressures from climate change, harvest of living resources and industrial development. The discussions will relate to the potential for developing an ecosystem–based management of human activities in the Arctic which can cope with the challenge.
Organized by Anders Mosbech (amo@bios.au.dk) on behalf of Arctic Research Centre, Aarhus University, and Copenhagen University. Please submit propsals to the organizer.
PROGRAMME:
09.15
Introduction Anders Mosbech
09.20
Arctic Limnic ecosystems, fragility and robustness
Erik Jeppesen, professor, Aarhus University
09.40
Species responses to Arctic climate change: lessons from spiders and insects
Toke T. Høye, Senior Scientist, Aarhus University
10.00
Arctic Terrestrial Ecosystems, fragility and robustness to changes in snow cover
Niels Martin Smidt, Senior Scientist, Aarhus University
10.20
Break and coffee/tea
10.40
Effects of pollutants on marine mammals in the Arctic; are Arctic marine mammals fragile or resilient from a wildlife veterinarian point of view?
Christian Sonne, Senior Scientist, Aarhus University
11.00
A whaler’s ’Catch-22’
Pelle Tejsner, Prof (assist), Aarhus University
11.20
Arctic Marine ecosystem, fragility and robustness
Mikael Sejr, Senior Scientist, Aarhus University
11.40
Microbial Degradation of Oil in the marine Arctic
Anders Johnsen, Senior Scientist, GEUS
12.00 Final Discussion
12.10 Lunch
ABSTRACTS
Arctic Limnic ecosystems, fragility and robustness
Professor Erik Jeppesen, Aarhus University
Freshwater ecosystems in the Arctic are undergoing major changes at present. Many new lakes and streams are formed when the glaciers retreat and where precipitation as rain increases, while others disappear due to local higher evaporation. Isolated lakes may be connected to the sea when precipitation shifts from snow to rain, and this may have drastic effects on their ecosystems due to fish migration/colonisation. The freshwater ecosystems are therefore highly affected by warming and also highly sensitive to others stressors, such as nutrients derived from a growing use of their catchments for agriculture.
Species responses to Arctic climate change: lessons from spiders and insects
Toke T. Høye, Senior Scientist, Aarhus University
Spiders and insects are very sensitive to temperature change. Recent research from Greenland has demonstrated that this group of organisms forms an illustrative example of the ways in which climate is affecting Arctic species. We present examples of changes in body size, seasonal dynamics and abundance of different species of insects and spiders in response to ongoing warming and discuss how we can use these insights as basis for predictions about the long-term ecological consequences of Arctic climate change.
Arctic Terrestrial Ecosystems, fragility and robustness to changes in snow cover
Niels Martin Smidt, Senior Scientist, Aarhus University
The rapid and directional change in arctic climate is challenging the arctic ecosystems. In particular changes in snow cover may affect numerous patterns and processes in the terrestrial (tundra) ecosystem. Based on examples of observed changes in the tundra system obtained from the long-term monitoring program Zackenberg Basic in Northeast Greenland, my presentation will outline the current and near-future climate-induced changes and their likely effects on the structure and function of the high arctic tundra ecosystem.
Effects of pollutants on marine mammals in the Arctic; are Arctic marine mammals fragile or resilient from a wildlife veterinarian point of view?
Professor Christian Sonne, Veterinary Ecotoxicology and Wildlife Medicine, Aarhus University
Marine mammals in the Arctic are facing multiple ecological stressors which include long-range transported pollution, increasing temperatures and loss of sea-ice, novel invasive diseases and aboriginal hunt among others. The effects from pollution and climate change on reproduction, immunity and survival have been studied for decades while the effects from introduction of new diseases due to global changes is a relatively new research field. Arctic marine mammals are due to their trophic position highly exposed to anthropogenic contaminants and infectious diseases and parasites which is also the case for the humans that hunt and eat them. When the ice is melting and the sea-ice is decreasing the contaminant exposure changes as does the hunt of the animals and human exposures. The fragility of the system and the species themselves all depends on the evolutionary mechanisms as well as the flexibility of prey access and new possibilities. The talk will focus on the reproductive, immune and skeletal systems.
A whaler’s ’Catch-22’
Pelle Tejsner, Prof (assist). Arctic Research Center (ARC), Aarhus University
Aarhus University. E-mail: tejsner@cas.au.dk, Phone: +45 87163239
Whaling has formed a central aspect in the harvest of living resources among Arctic indigenous people for the past 4000 years; however, contemporary political, economic, industrial, and regulatory frameworks have gradually altered this ancient practice while annual quota allocations for species such as beluga whales (Delphinapterus leucas) occasionally feature as a source of socio-economic conflict between different groups of hunters. The co-management regulations for whaling (introduced in the early 1990s), and its concomitant framework of rights as these pertain to different users, has been met with mixed responses among respective permit holders along the Greenlandic coast. Although local hunters and fishermen understand the need for observing the Self-Rule government’s regulations from a conservationist point of view, they simultaneously identify considerations that address the traditional web of connectivity that continues to exist between humans and the coastal environment, conflicting idea systems and more recent concerns over increased industrial and shipping-based activities in local waters. Based on a review of local user concerns as these relate to the whaling co-management framework, and with a view to increased industrialisation in the Arctic, this presentation provides a tentative sketch of what the future sustainable management of renewable resources could entail - from a resource-user perspective.
Arctic Marine ecosystem, fragility and robustness
Mikael Kristian Sejr, Senior Scientist, Aarhus University
The Arctic is warming at a faster rate than the global average. Combined with reduction in sea ice coverage this is often used as the reason for why the Arctic marine ecosystem is considered especially fragile. However, large regional differences in the Arctic exist, and species and ecosystem within the Arctic are likely to respond very differently in the future. Through examples of observed and predicted responses of different marine ecosystem components I will show that improved ecosystem understanding is necessary in order to improve our ability to predict impacts of warming and other anthropogenic stressors in the Arctic.
Microbial degradation of oil in the marine Arctic
Senior Scientist Anders R. Johnsen1, Mette Christensen1,2, Linus M. V. Malmquist2, Jens Aamand1, Jan H. Christensen2
1GEUS, 2KU-PLEN
We carried out a qualitative evaluation of the metabolic potential for microbial degradation of oil in water from the Disko Bay and the Baffin Bay Knowledge on the intrinsic potentials for oil biodegradation in potential offshore oil drilling areas is crucial to predict the fate of oil released in accidental spills, as biodegradation is the only removal process in deep water bodies. Whereas most previous studies have focused only on alkane, BTEX or total oil removal, we have instead investigated the potential for microbial growth on 15 model-substrates, and fingerprinting of large oil-compound classes. Oil degradation experiments were carried out in-situ in the Disko Bay and in microcosms in the lab. Altogether, our results indicate that oil degradation potentials in the water columns of the pristine Disko Bay and Baffin Bay areas are quite limited, whereas the bacteria from harbor environments (Qeqertarsuaq/Godhavn) have adapted to oil degradation and show a broader substrate range.
