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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2024

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Abstract

There is an increasing need for ecosystem-level distribution models (EDMs) and a better understanding of which factors affect their quality. We investigated how the performance and transferability of EDMs are influenced by 1) the choice of predictors and 2) model complexity. We modelled the distribution of 15 pre-classified ecosystem types in Norway using 252 predictors gridded to 100 × 100 m resolution. The ecosystem types are major types in the ‘Nature in Norway' system mainly defined by rule-based criteria such as whether soil or specific functional groups (e.g. trees) are present. The predictors were categorised into four groups, of which three represented proxies for natural, anthropogenic, or terrain processes (‘ecological predictors') and one represented spectral and structural characteristics of the surface observable from above (‘surface predictors'). Models were generated for five levels of model complexity. Model performance and transferability were evaluated with data collected independently of th

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Abstract

The Norwegian Environment Agency has asked VKM to evaluate the risks to biodiversity associated with the import of two species of leeches to Norway, Hirudo medicinalis and H. verbana (so-called medicinal leeches). In addition, they ask that the project group suggest mitigating measures that could reduce any potential risks, should import of the two species be granted. Background Bloodsucking leeches have been employed by humans for millennia. The two species Hirudo medicinalis and H. verbana have dominated the trade in medicinal leeches in Europe. Overcollection combined with loss or degradation of freshwater habitats led to a precipitous decline in European populations by the 1800s and led to a corresponding increase in imports from Turkey, North Africa, Russia and the Middle East. By the turn of the 19th century, the demand for live leeches in Europe had tapered off as contemporary medicine developed, only to have a small resurgence over the last decades as live leeches became recognized as useful for a variety of medical and cosmetic procedures, and to be the source of bioactive molecules of interest to medical researchers. As traditional medicine in Asia also uses a variety of leech products, there is a robust global market for live leeches and leech derivatives that is being met mostly by leech aquaculture, where the live leech trade seems dominated by H. verbana. There is increasing interest in commercializing production and sale of three similar leech species, H. orientalis from Central Asia, H. sulukii from a small region in Turkey, and H. troctina from North Africa. Hirudo medicinalis has been used medicinally in Norway since at least the Middle Ages when they were used by barber-surgeons for bloodletting. Leeches have been dispensed by apothecaries up until the end of the 1950s. Phylogeographic studies have treated the species as native to southern Norway and the Norwegian Biodiversity Information Centre has numerous records of H. medicinalis, with recent records primarily from the eastern coast of southern Norway. The Norwegian Red List for Species categorizes H. medicinalis as being of Least Concern in Norway. Hirudo verbana naturally occurs in southern Europe and has not been observed in Scandinavia so far (see map in Figure 2). Methods for the risk assessment VKM established a small working group with expertise in invertebrates and risk assessment. Our group combed the scientific literature and relevant websites for information on the taxonomy, natural history, ecology, and medical uses of medicinal leeches broadly and H. medicinalis and H. verbana specifically. The project group contacted major leech providers in Europe and North America to learn more about leech production and sale. Using the EICAT (Environmental Impact Classification for Alien Taxa) system developed by the IUCN, The project group identified those mechanisms (“hazards”) through which these two species could affect native biodiversity in Norway should imported specimens become established in Norwegian nature, and characterized the risk related to each of these hazards. The project group then conducted a semi-quantitative risk assessment for the species according to four categories: Low, Medium, Possibly high, and High risk. Hazards: how likely, how impactful, and overall risks In our report, VKM regard H. medicinalis as a native species, since it is so treated by Hirudo experts and is widespread in Norway. The project group regards H. verbana as non-native to Norway. The potential hazards from the EICAT system that could be associated with introducing one or both species include predation and parasitism, competition, disease transmission, and hybridization. ................................ .................................... Conclusions VKM concludes that the overall risk to biodiversity in Norway from importing live H. medicinalis and H. verbana is low.

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Abstract

The Norwegian Environment Agency asked VKM to evaluate the risks to biodiversity associated with the importation of eight species of live crabs intended for human consumption. Background Invasive crab species represent a significant threat to biodiversity globally due to their omnivory, adaptability to diverse habitats, high reproductive output, and aggressive behaviour. The Norwegian Environment Agency has raised concerns about the potential ecological risks posed by the import of live crabs to Norway intended for human consumption. This report provides a risk assessment of eight species of crabs that could have negative effects on native biodiversity. The species include Chinese mitten crab (Eriocheir sinensis), Japanese mitten crab (E. japonica), blue crab (Callinectes sapidus), Atlantic rock crab (Cancer irroratus), Asian paddle crab (Charybdis japonica), common moon crab (Matuta victor), African blue swimming crab (Portunus segnis), and Harris mud crab (Rhithropanopeus harrisii). Three of the assessed species were recently confiscated at Norway's border. This suggests a market demand that could increase the frequency of introductions to Norway. Methods VKM established a working group with expertise in invertebrates and risk assessment. The group searched scientific literature for information on the taxonomy, natural history, invasiveness, and ecology for each crab species. If scientific literature was lacking, supplemental google searches allowed for a broader understanding of species with limited research or on the use and transportation of live crabs as food. The assessment utilized the EICAT framework (Environmental Impact Classification for Alien Taxa) to identify potential mechanisms by which each species could harm native biodiversity, should imported specimens become established in Norwegian nature. Key mechanisms include competition, predation, pathogen transmission, and hybridization. The relevant mechanisms were analysed for each species by rating the potential magnitude of impact on biodiversity from minimal to massive. The likelihood of each impact was assessed from very unlikely to very likely. A combination of magnitude of impact and likelihood resulted in final risk levels ranging from low and medium to possibly high and high. Confidence levels for each assessment were also categorized as low, medium, or high based on expert opinion. Results The potential hazards evaluated under the EICAT framework include competition, predation, and transmission of disease for all species, grazing for four species and structural impacts on the ecosystem for three species. The conditions required for crabs imported live for human consumption to reach a natural ecosystem in Norway include a commercial demand for crabs, survival during transport and handling, and the possibility of release or escape. If these conditions for reaching a natural ecosystem are met, the species must then be capable of establishment in the new ecosystem. There are several examples of species imported live for human consumption becoming established in the wild, most likely due to intentional release. The risk assessments indicate varied levels of risk across the five hazards. Competition from E. sinensis or E. japonica was assessed to pose a high risk, while competition from C. sapidus, C. irroratus, M. victor, P. segnis, or R. harrisii was assessed to pose a medium risk. Predation by E. sinensis or E. japonica was assessed to pose a high risk and predation from R. harrisii, C. sapidus, C. irroratus, M. victor, or P. segnis was assessed to pose a medium risk. Transmission of disease from either E. sinensis or E. japonica was assessed to pose a high risk, while there was a possibly high risk of disease transmission from C. irroratus. The diseases of highest concern include the crayfish plague (Aphanomyces astaci) and gaffkaemia (Aerococcus viridans var. homari). Finally, there was a moderate risk of ......

Abstract

Only approximately 2% of the land area in Northern Norway is suitable for agricultural purposes. The short growing season and cold climate impose limitations for what can be produced. Agriculture still takes place here, with forage crops for livestock being the most important. On free rangeland areas, including both semi-natural and natural habitats, livestock grazing is common. The biomass production on some of these rangelands is presumed to be high, although little is known about the actual fodder potential. In 2022 a preliminary study was performed to determine abundance and variety of wild pasture plants, dry matter yield (DM) and feed quality in the (presumed) highest yielding vegetation types. Results showed an average of 1520 kg DM ha–1 in spring and 5380 kg DM ha–1 in autumn. Early season feed quality was high, but with rapidly decreasing trends. The number of pasture plants was also high. Our results show that in sub-arctic Northern Norway grazing animals can harvest substantial amounts of ‘free’ fodder of good quality, yet the official statistics show that only 14% of this resource is utilised. Continuous grazing is needed to maintain production and fodder quality in these areas.

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Abstract

Six cattle breeds native to Norway, have for almost half a century been at risk of extinction. Due to their small population sizes, they have hardly been improved by breeding for many decades. Still, the endangered breeds represent a source of genetic diversity with special milk qualities compared to the modern breed, Norwegian red (NRF). This study reports for the first time a detailed overview of their milk composition. Milk from seven native breeds, in total 200 individuals, were included in the study. Rare genetic variants of αs1-and αs2-casein, and β-casein A1 and κ-casein B were more prevalent in milk form the endangered breeds compared to NRF. Moreover, milk from these six breeds showed better renneting properties and lower incidences of non-coagulating milk, compared to the NRF milk, which showed better acid coagulation properties. This study shows the potential for native breeds in small-scale production of high-quality rennet cheeses.

Abstract

Insight from new technology in rangeland grazing systems Inger Hansen, Lise Grøva, Michael Angeloff and Oddbjørn Kaasa Although digital technologies and innovations are increasingly being adopted and accepted in intensive livestock systems, they are poorly developed and implemented in extensive livestock farming systems. On-animal sensors have potential to remotely monitor and identify changes in animal behaviour, such as illness, accidents or depredation. Real time monitoring of livestock may allow farmers and ranchers to respond more rapidly when animals become ill, and by this ensure both production and welfare With the rapid increase in new data from digital technologies from livestock rangeland grazing systems, there is a need to explore the potential for new knowledge and new tools that these data may provide. The potential lies in multisource data analysis to generate new insight on sheep behaviour, interactions and possible criteria for Early Warning Systems (EWS). EWS is in high demand by farmers, authorities and all stakeholders to ensure the sustainable management of our rangeland grazing resources. In Norway we have now started a pilot work to integrate data from GPS tracking collars on free ranging sheep with individual sheep health and production data sources, as well as vegetation maps, weather conditions, human activity and predator killings. Since 2015, Meråker grazing group, consisting of 25 sheep farmers, have used GPS tracking collars on about 2000 ewes from June to September. The data set consists of more than 9 million positions, allowing analysis of the sheep's movement related to numerous environmental and production factors. Integration of these position data with production-, health-, large carnivores- and other explanatory variables, and analysis of these multisource data, has potential to be a game changer for rangeland grazing systems. This presentation will highlight the the potiential for new insight in these farming systems.