Svalbard: projects/activities

The aim of this research program is to examine the response of animal populations to environmental variability at different spatial scales. We attempt to determine how individuals respond to the spatial heterogeneity of their environment, and what are the consequences of this response for the dynamics of subdivided populations. Specifically, we consider an ecological system involving biotic interactions at three levels: seabirds, their tick _Ixodes uriae_, and the microparasite _Borrelia burgdorferi_ sensu lato (Lyme disease agent). Colonies of seabirds represent discrete entities, within and among which parasites can circulate. Our previous work on this system in the norwegian arctic has enable us to show that (1) host dispersal can be affected by local conditions, (2) seabird tick populations are specialised among different host species, namely between sympatric kittiwakes _Rissa tridactyla_ and puffins _Fratercula arctica_, (3) in the kittiwake, females transmit antibodies against _Borrelia burgdorferi_ when their chicks have a high probability to be exposed to the tick vector. We propose to combine different approaches, incorporating field surveys and experiments and population genetic studies (of hosts and parasites), in order to better understand the role of local interactions and dispersal in the dynamics of such a system. The research program implies collaborations with researchers from other french groups, as well as with Canadian (Queen’s University) and Norwegian colleagues (from NINA and the University of Tromsø).

In the late seventies, ELLIOTT and KINGSTON (1987) discovered a polychaetous annelid in various North Sea estuaries that had previously been found only in North American estuaries. Further specimens of what appeared to be the same species were found in the mid-eighties in the coastal waters of the Baltic Sea (BICK and BURCKHARDT, 1989). The distribution of these events in time and space led to the assumption that a North American species had immigrated to the North Sea and then extended its range of distribution to the Baltic. Within several years this species became one of the most dominant species in these estuaries. Identification of the immigrant was beset with problems from the start. It was identified as M. wireni AUGENER, 1913 or as M. viridis (VERRILL, 1873). It was the population genetic studies by BASTROP et al. (1995) and ROEHNER et al. (1996a, b) that showed the presence of genetically distinct forms in the North and Baltic Sea as well as in different regions of the north eastern coast of America. The morphological studies undertaken against this background allowed a good discrimination between these species (BICK & ZETTLER, 1997). Though, all authors dealing with the two species immigrated into the European estuaries were unable to name these species. The main reasons for this uncertainty are: - species identification is difficult, because diagnostic characters vary with growth (BICK, 1995), - the geographical distribution of Marenzelleria species is far from clear, - type material no longer exists or it is in poor condition (BICK & ZETTLER, 1997). Specimens of the type species of the genus, Marenzelleria wireni, were recorded from the Arctic region, Franz-Joseph Land and Spitzbergen (WIREN, 1883 and von MARENZELLER, 1892). As mentioned above, these specimens deposited in the Zoologisches Museum Hamburg and the Swedish Museum of Natural History, Stockholm are in poor condition. As far as we know further material from these regions does not exist. In order to eliminate the taxonomic uncertainty it is necessary to investigate morphologically and genetically specimens from the type locality.

Description of parameters of the population dynamics of polar bivalve communities, first year: growth and reproductive cycle of the dominant Greenland cockles (Serripes groenlandicus)

Biological nitrogen fixation by cyanobacteria is a key process for productivity in terrestrial Arctic ecosystems and the activity is dependent of size and diversity of cyanobacterial populations. Changes in biodiversity after pertubations of different types of habitats simulating climatic changes or other antropogenic effects will be studied by molecular methods and correlated to variations of nitrogen fixation activity.

The structure and role of the cyanobacterial communities that colonise bare soils and fix nitrogen in the arctic ecosystem will be studied. The planned activities will focus on the isolation, identification and characterisation of cyanobacteria from arctic habitats and on the changes of the cyanobacterial community along a transect from a retreating glacier front to a more stable habitat characterised by the presence of mature vegetation. For these purposes, a polyphasic approach encompassing microbiological, morphological and molecular techniques will be applied to environmental samples and isolated cultures. The obtained results will give new insights on the diversity and role of nitrogen fixing cyanobacteria in the arctic and, in more general terms, on ecosystem development under changing climatic conditions.

Benthic macroalgae communities of the arctic ocean provide habitat, protection, nursery and nutrition to a large number of invertebrates. In contrast to temperate and tropical regions the basic ecological interactions between zoo- and phytobenthos of the Arctic are little understood. Therefore this project for the first time investigates biological and chemical interactions between invertebrates and macroalgae on Spitsbergen/Svalbard (Koldewey Station) with special emphasis on defense mechanisms against grazing pressure. Initial diving-investigations will map the invertebrate fauna which is associated with the macroalgae; the following feeding-experiments with herbivorous animals aim to selectively identify generalists, generalists with preference or specialists. Additional bioassays serve to reveal structural and/or chemical properties of those plants, which affect a specific impact on the grazing of herbivores. Our investigations on the chemical protection of the algae against grazing focus on the basic mechanisms and the chemical structure of potent secondary metabolites carried out in cooperation with natural product chemists.

Succession of communities and individual growth of benthic invertebrates are more or less unknown in polar waters, but nevertheless are the basic parameters of understanding the benthic sub-ecosystem, delivering data for modelling and prediction of the system´s development. Three localities, two in the Antarctic and one in the Arctic, the Kongsfjord in Spitsbergen, have been choosen as investigation localities. Hard and soft substrates, which will be sampled in regular intervalls during the duration of the project, will be deployed at different depths. The analysis includes species composition, species growth and, with respect to soft substrates, sediment parameters.

This project (of Humboldt University of Berlin) is a long-study of the ecology and physiology of Arctic snow algae in Ny Ålesund region (Krossfjorden, Blomstrandhalvøya and Prins Karls-Forland). The main objectives are: - Characterision of snow algae fields and probe collections - Physiological characterision of single algae cells at different stages of development (e.g. by dielectric single cell spectroscopy, immuno-fluroescence microscopy and element analysis) - Cultivation in home laboratories.

This study aims at reconstructing the Barents Sea marine ecosystem before the exploitation by man. This reconstruction will be made by using the existing archival resources on catch statistics from the 17th to 19th centuries in the Netherlands, Germany, Denmark and the United Kingdom, in combination with the present knowledge an animal behaviour and food web structure. Fieldwork is planned in two former hunting areas in Spitsbergen: the Smeerenburgfjord and the Storfjord to study both the structure of the recent marine ecosystem and the composition, size and dating of the recent bird rookeries. This information in combination with the historical data will be used to reconstruct the original ecosystem.

The ecology of the Greenland Right Whale is studied using the historical information from written sources from Dutch archives. The Spitsbergen and Davis Strait populations of the Greenland Right Whale were so heavily hunted that they are almost exterminated now in the northern waters. The whale bones on the beaches of Arctic islands are the archaeological evidences of this exhausting hunt. Very often whaling logbooks, crew statements and lists of catch figures are the only sources of information preserved of this animal in these regions. In this project recent biological information of the animal in the seas around Alaska and historical information of the whale in the North Atlantic and Davis Strait is used to reconstruct the migration, distribution and ecological behaviour of the Greenland Right Whale in the North Atlantic Ocean.

Determining ecological constraints for Barnacle Geese during the Arctic summer to understand individual breeding success. Geese are individually marked, measured and observed over their lifetime in order to study individual reproductive strategies and their consequences. Also the interaction between the geese and their food plants is studied in detail. Research activities Every year, during summer, fieldwork in Ny Ålesund, every two years counting geese along Norden-skioldkysten. Both areas are located on Spitsbergen.

In the seventeent and eighteenth centuries intensive European whaling and walrus hunting took place in the waters around Spitsbergen, with many stations on the coast of the islands. The hunt was carried out in areas along the edge of pack ice and is therefore very sensitive to changes in the ice situation and climate. When, around 1650, climate and ice distribution changed, whales moved to the north. The whaling stations in the south of Spitsbergen were abandoned when stations in the north were still functioning. When, later, the ice situation deteriorated in the north as well, the stations were abandoned there too. Shore whaling changed into pelagic whaling. Because of these whaling and walrus hunting activities two very numerous large mammals were largely depleted and almost disappeared from the Spitsbergen waters. The pelagically feeding Greenland Right Whale and the bentically feeding walrus, whose initial stocks are estimated at 46,000 Greenland Right Whales and 25,000 walrus, were eliminated. This elimination has caused a major shift in the foodweb. The plankton feeding seabirds and polar cod strongly increased because of the elimination of the Greenland Right Whale, and the eider ducks and bearded seals increased because of the decrease of the number of walruses. This development has led to the enormous amount of seabird rookeries on the West coast of Spitsbergen.

The project aims to describe the environmental status of marine sediments in van Mijenfjorden. This to provide baseline data of contaminants and biodiversity, as well as for monitoring of eventual contamination from industrial activities (coal mining).

Investigation of benthic faunal communities for: taxon distribution/ biodiversity mapping; examination of effects of glacial and physical disturbance on community structure; relation between faunal structure and sediment contaminants.