Project Antarctis
The role of human activities in the introduction of non-native species into Antarctica and in the distribution of organisms within the Antarctic
UBA Research & Development Project 01.10.2009 – 30.09.2011
FKZ 3709 85 157a
The main goal of the project was to assess the potential influence on Antarctic terrestrial ecosystems by increasing tourism. The project aimed at estimating the anthropogenic influence on the distribution of organisms within as well as on the introduction of non-native species into Antarctica, both in areas frequently visited by tourists and near research stations. Furthermore, the efficiency of possible preventive and precautionary measures was be investigated and evaluated.
Changes in species’ distributions are best considered within the framework of landscape ecology, which is, however, difficult to study in continents such as Antarctica. Due to their very small radius of action and their extreme habitat fidelity, soil organisms allowed the study of landscape-level processes at very small spatial scales. Taxonomically, soil organisms have been relatively well studied in Antarctica and are important, species- and individual-rich components of terrestrial ecosystems, especially in biotically relatively simple ecosystems as in Antarctica. Therefore, the present study concentrated on soil organisms (flora and fauna), which allowed the research questions to be answered in a necessarily limited area of the Antarctic Peninsula.
Although literature concerning Antarctic soil flora and fauna as well as biological databanks for the Antarctica exist, with which taxonomic results could be compared, data from the possible origins of neobiota, e.g., the southern regions of South America, was practically non-existent. It was thus nearly impossible to evaluate whether detected but unknown species were undescribed endemics of Antarctica or originated from southern hemispheric continents. The evaluation of possible anthropogenic affects on species’ distributions was therefore be approached indirectly at different levels:
- Changes in the ß-diversity, i.e. the biodiversity of different microhabitats, within single locations. Especially in fragile and ecologically limited ecosystems as in Antarctica, undisturbed sites contain diverse microhabitats. These microhabitats harbour different species compositions and community structures, i.e. ß-diversity is high. In locations with high tourism pressure, species introduction can be higher between microhabitats of a single location than between continents, resulting in a biotic homogenisation of microhabitats and an overall reduction in the ß-diversity of a location.
- Zoogeographical distribution patterns. Different locations along the coast of Antarctica will be sampled, allowing the evaluation of the biogeographical distribution patterns of the registered species at larger spatial scales. In sites with high tourism pressure, a species composition containing more species with a wide distribution range and fewer locally endemic species than undisturbed sites, can indicate an anthropogenic influence on the distribution patterns of Antarctic organisms. Depending on the presence of locally endemic or more widely distributed species, possibly endangered locations (i.e., those with high levels of endemism) will be identified that should be exempted from tourism.
- Possible direct proof of introduced species. Despite the lack of taxonomic knowledge of southern-hemispheric soil organisms, introduction of some non-native species in Sub Antarctic islands, where the climatic conditions are not as harsh, is known. Registration of these species on the Antarctic continent – while not very probable due to climatic differences – will directly and explicitly indicate the introduction of none-native species.
- Evaluation of possible direct mechanisms of species introduction (“bootwashing”). A likely mechanism of species’ introduction is direct dispersal by, i.e., the footwear of visiting tourists. Therefore, the shoes and boots of tourists will be sampled and studied before and after visiting locations on the Antarctic continent for the presence of soil organisms.
The research project was commissioned by the German Federal Environment Agency and is carried out by the Senckenberg Museum of Natural History Görlitz, Germany, in close co-operation with international experts on soil invertebrates (Mikhail Potapov, Moscow; Alexander Brückner, Vienna; Sandra McInnes, Oxford). It is graciously supported by two cruise tour operators (Hapag-Lloyd and Delphin Tours) and their expedition leaders.
In the Antarctic summer of 2009/2010 soil samples were taken from nine different sites of the Antarctic Peninsula; six of which were frequently visited by tourists, three by research personal .
Sampling occurred in a statistical block design, comparing areas of high human impact with closely neighbouring areas without impact. Samples were transported back to Germany, where soil animals were extracted by various methods – on average 1-2 weeks after sampling – and then sorted into the animal groups Collembola, Oribatida, Gamasina, Prostigmata, Nematoda and Tardigrada. All animals were individually embedded on microscopic slides and determined to species level by the participating European taxonomic specialists. Ground vegetation occurring on the samples (mostly mosses, lichens and algae) were determined directly after animal extraction. Soil chemical and physical analyses of the samples were subsequently performed to ensure comparability of the contrasted sampling areas.
Determination of some animal groups is still ongoing. To date over 70 species of soil organisms have been identified, with many more still expected. Antarctic sites frequented by tourists are generally areas with high wildlife density (penguins, seals). The influence of this wildlife on soils and soil organisms can mask human trampling effects. Despite such difficulties, reduced
Example of the microarthropod densities in the sampling sites of one location (Arctowski Station, King George Island) densities in human-impacted areas could be detected for soil animals in general and especially for Collembola and Oribatida. These preliminary results were, however, site specific. Due to the still ongoing determination, effects on total species richness have not yet been determined. Nonetheless, based on data from Collembola and Oribatida, a reduced variability between species assemblages of human-impacted sites could be statistically identified, albeit somewhat marginally. This indicates a reduced ß-diversity of soil animal communities (“community homogenization”) within these localities due to human influence. This must still be confirmed with the data from all organism groups. As of yet, possibly introduced non-indigenous species (Collembola, Prostigmata) have only been identified from one location (Deception Island). Especially this site has a long history of human activity and, in particular, has warmer soils due to volcanic activity, which allows occurrence of species not adapted to Antarctic environmental conditions.
In the Antarctic summer of 2010/2011 seven sites – five of which were different from the previous year – were sampled as described above.
Sample processing, again as stated above, is presently ongoing. Additionally, on one cruise ship tour, the efficacy of on-board boot-washing techniques was tested by spot tests of a representative subset of the passenger’s boots after they were returned to the passenger’s lockers. Preliminary results show that boot-washing was not 100% effective, as sporadic individuals of soil animals (mainly Nematoda) could be identified from the boots after disinfection and boot-washing. This is most probably not due to an inherent inefficiency of the boot-washing methods, but rather to tourist behaviour regarding the methods. Furthermore, it could not be determined whether the soil animals remained
viable after disinfection, which should be tested by direct ecotoxicological experiments with the disinfectant. Final results of the study are expected by mid-2012.
Besides direct comparison of the identities of registered species with known non-native species, the biological data will be analysed using various biodiversity parameters (α-, β- and γ-diversity) of microhabitats, locations and all locations together. Comparison of the ß-diversity within anthropogenically influenced and relatively uninfluenced sites will allow identification of the level of disturbance on species’ distributions and thus potential introduction of species at small spatial scales. Based on the observed distribution of registered species throughout all sampling sites, species will be indentified that have wide and limited (= “locally endemic”) distributions. The proportions of these species groups will then be evaluated for each sampled location. A comparison of these proportions in touristically frequently and infrequently visited locations will provide an indication of anthropogenic species dispersal at larger spatial scales.
Projektpartner
German Federal Environmental Agency (Section I 3.5 – Protection of the Antarctic)
Fritz Hertel
Senckenberg Museum für Naturkunde Goerlitz, Germany
Dr. Axel Christian (Gamasida)
Dr. Karin Hohberg (Nematoda)
Dr. Volker Otte (Mosses, Lichens)
Dr. David Russell (Actinedida)
Pedagogical University Moscow, Russia
Dr. Mikhail Potapov (Collembola)
University of Natural Resources and Life Sciences Vienna, Austria
Prof. Dr. Alexander Brückner (Oribatida)
British Antarctic Survey, Cambridge, UK
Dr. Sandra McInnes (Tardigrada)
