Anders Nielsen
Head of Department
Authors
Gaute Velle Lennart Edsman Charlotte Evangelista Stein Ivar Johnsen Martin Malmstrøm Trude Vrålstad Hugo de Boer Katrine Eldegard Kjetil Hindar Lars Robert Hole Kyrre Linné Kausrud Johanna Järnegren Inger Elisabeth Måren Erlend Birkeland Nilsen Eli Knispel Rueness Eva Bonsak Thorstad Anders NielsenAbstract
No abstract has been registered
Authors
Claus Rasmussen Yoko L. Dupont Henning Bang Madsen Petr Bogusch Dave Goulson Lina Herbertsson Kate Pereira Maia Anders Nielsen Jens M. Olesen Simon G. Potts Stuart P. M. Roberts Markus A. K. SydenhamAbstract
A recurrent concern in nature conservation is the potential competition for forage plants between wild bees and managed honey bees. Specifically, that the highly sophisticated system of recruitment and large perennial colonies of honey bees quickly exhaust forage resources leading to the local extirpation of wild bees. However, different species of bees show different preferences for forage plants. We here summarize known forage plants for honey bees and wild bee species at national scale in Denmark. Our focus is on floral resources shared by honey bees and wild bees, with an emphasis on both threatened wild bee species and foraging specialist species. Across all 292 known bee species from Denmark, a total of 410 plant genera were recorded as forage plants. These included 294 plant genera visited by honey bees and 292 plant genera visited by different species of wild bees. Honey bees and wild bees share 176 plant genera in Denmark. Comparing the pairwise niche overlap for individual bee species, no significant relationship was found between their overlap and forage specialization or conservation status. Network analysis of the bee-plant interactions placed honey bees aside from most other bee species, specifically the module containing the honey bee had fewer links to any other modules, while the remaining modules were more highly inter-connected. Despite the lack of predictive relationship from the pairwise niche overlap, data for individual species could be summarized. Consequently, we have identified a set of operational parameters that, based on a high foraging overlap (>70%) and unfavorable conservation status (Vulnerable+Endangered+Critically Endangered), can guide both conservation actions and land management decisions in proximity to known or suspected populations of these species.
Authors
Eli Knispel Rueness Maria Gulbrandsen Asmyhr Hugo de Boer Katrine Eldegard Lars Robert Hole Kjetil Hindar Johanna Järnegren Kyrre Linné Kausrud Lawrence Richard Kirkendall Inger Elisabeth Måren Erlend Birkeland Nilsen Anders Nielsen Eva Bonsak Thorstad Gaute VelleAbstract
Key words: Ursus maritimus, CITES, polar bear, Non-Detriment Finding, Norwegian Scientific Committee for Food and Environment, Norwegian Environment Agency, VKM Background: Canada is the only nation in the world that allows commercial export of polar bear products harvested from its own wild populations. Norway is among the destinations for exported material. Polar bears are listed on CITES appendix II and on list B of the Norwegian CITES Regulation. Import of harvested polar bears to Norway requires both export permits from the Canadian CITES authorities and import permits from the Norwegian Environment Agency. Consequently, a Non-Detriment Finding (NDF) is mandated and was commissioned by the Norwegian Environment Agency (Norwegian Management Authority for CITES) to the Norwegian Scientific Committee for Food and Environment (VKM) (Norway’s CITES Scientific Authority). The NDF is a scientific risk assessment evaluating whether or not international trade can be detrimental to the survival of polar bears. The risk assessment may also be used by the Norwegian Environment Agency to assess whether the polar bears should be placed on Norwegian CITES list A. Currently, the IUCN/SSC Polar Bear Specialist Group (PBSG) recognizes 19 subpopulations of polar bears in the circumpolar Arctic, of which 13 reside wholly (9) or partly (4) in Canada. Together, these 13 populations account for about two thirds of the world’s total polar bear population. This risk assessment considers the populations that are within the hunting areas. Methods: VKM has reviewed current knowledge about polar bear biological characteristics, population status and trends in subpopulations. Scenarios for the future development of the Arctic environment, to which the species is inextricably adapted, are presented. Habitat loss due to declining sea ice is widely recognized as the main threat to polar bears, and this, as well as other obstacles to the species survival, has been evaluated. The various legislations, regulations and monitoring regimes of the range countries are briefly summarised. Moreover, international trade in polar bear products has been analysed. VKM has further undertaken an assessment of data quality and uncertainties. In order to gain access to the most recent information on polar bear biology and management, four scientists from the PBSG were interviewed and the transcripts of the interviews (with consent from the hearing experts) are attached to this report. Results: The best scientific knowledge available for polar bears in Canada suggests that four subpopulations are in decline, two are stable, and one is increasing, while the population trends for the remaining subpopulations are unknown. Noteworthy, all the estimates of population size are highly uncertain. Survey methods also changed between the 2008 and 2018 population estimates used for quota setting. Moreover, data are in most areas collected too infrequently to detect rapid changes in population size. Particularly, under changing environmental conditions. The prognosis for the Arctic marine environment points towards continuing habitat loss and inevitably further decline for the polar bear population. Analyses of data from the CITES trade database reveal a dynamic international market for polar bear products with significant changes in destination countries and the purpose for transactions. The United States was the main importer of polar bear products, mainly hunting trophies, until listing the polar bear as a threatened species in 2008. In more recent years, China has become the major importer, with hides being the preferred product. Simultaneously with these changes, there has been a significant increase in the price of polar bear hides. Conclusion: Several polar bear subpopulations are in decline. Predictions of continuing habitat loss points to further decline. While not the main threat to polar bear survival, international trade .......
Abstract
1. Ecological network theory hypothesizes that the structuring of species interactions can convey stability to the system. Investigating how these structures react to species loss is fundamental for understanding network disassembly or their robustness. However, this topic has mainly been studied in‐silico so far. 2. Here, in an experimental manipulation, we sequentially removed four generalist plants from real plant–pollinator networks. We explored the effects on, and drivers of, species and interaction disappearance, network structure and interaction rewiring. First, we compared both the local extinctions of species and interactions and the observed network indices with those expected from three co‐extinction models. Second, we investigated the trends in network indices and rewiring rate after plant removal and the pollinator tendency at establishing novel links in relation to their proportional visitation to the removed plants. Furthermore, we explored the underlying drivers of network assembly with probability matrices based on ecological traits. 3. Our results indicate that the cumulative local extinctions of species and interactions increased faster with generalist plant loss than what was expected by co‐extinction models, which predicted the survival or disappearance of many species incorrectly, and the observed network indices were lowly correlated to those predicted by co‐extinction models. Furthermore, the real networks reacted in complex ways to plant removal. First, network nestedness decreased and modularity increased. Second, although species abundance was a main assembly rule, opportunistic random interactions and structural unpredictability emerged as plants were removed. Both these reactions could indicate network instability and fragility. Other results showed network reorganization, as rewiring rate was high and asymmetries between network levels emerged as plants increased their centrality. Moreover, the generalist pollinators that had frequently visited both the plants targeted of removal and the non‐target plants tended to establish novel links more than who either had only visited the removal plants or avoided to do so. 4. With the experimental manipulation of real networks, our study shows that despite their reorganizational ability, plant–pollinator networks changed towards a more fragile state when generalist plants are lost.
Authors
Kjetil Hindar Lars Robert Hole Kyrre Linné Kausrud Martin Malmstrøm Espen Rimstad Lucy Robertson Odd Terje Sandlund Eva Bonsak Thorstad Knut Vollset Hugo de Boer Katrine Eldegard Johanna Järnegren Lawrence Richard Kirkendall Inger Elisabeth Måren Erlend Birkeland Nilsen Eli Knispel Rueness Anders Nielsen Gaute VelleAbstract
Key words: VKM, risk assessment, Norwegian Scientific Committee for Food and Environment, Norwegian Environment Agency, Norwegian Food Safety Authority Introduction: The Norwegian Environment Agency and the Norwegian Food Safety Authority asked the Norwegian Scientific Committee for Food and Environment to assess the risk to Norwegian biodiversity, to the productivity of native salmonid populations, and to aquaculture, from the spread and establishment of pink salmon in Norwegian rivers, and to assess mitigation measures to prevent the spread and establishment of this alien species. Pink salmon is native to rivers around the northern Pacific Ocean. The species usually has a strict two-year life cycle, with populations spawning in even and odd years being genetically isolated. Fertilized eggs of pink salmon were transferred from Sakhalin Island to Northwest Russia in the late 1950s, and fry were released in rivers draining to the White Sea. The first abundant return to rivers in Northwest Russia, as well as to Norway and other countries in northwestern Europe, was recorded in 1960. Stocking with fish from Sakhalin was terminated in 1979. By then, no self-sustaining populations had been established. From 1985 onwards, stocking in White Sea rivers was resumed with fish from rivers in the more northerly Magadan oblast on the Russian Pacific, resulting in the establishment of reproducing populations. Stocking was continued until 1999, when the last batch of evenyear fertilized eggs was imported, and the fry released in spring 2000. Thus, all pink salmon caught after 2001 in the Northeast Atlantic and the Atlantic side of the Arctic Ocean including the Barents Sea, as well as in rivers draining into these seas, are the result of reproduction in the wild. Pink salmon is now established with abundant and increasing stocks in Northwest Russia and regular occurrence in rivers in eastern Finnmark. Catches of odd-year adult pink salmon in Northwest Russia were usually below 100 tonnes before 2001 and increased to an annual average of 220.5 tonnes during the period 2001-2017. Even-year returns are smaller than odd-year returns both in Northwest Russia and in Norway. The number of pink salmon recorded in Norwegian rivers peaked in 2017, with a high number of fish in eastern Finnmark, and substantial numbers recorded in rivers all along the coast of Norway and in other European countries. In 2019, the area with abundant returns expanded in comparison with 2017, to include rivers in western Finnmark and Troms. The recorded numbers were perhaps lower in southern Norway in 2017 than in 2019 (full statistics not available when this report was finalised), but also in southern Norway there were more pink salmon in 2019 than in any year before 2017. The large numbers of pink salmon in western Finnmark and Troms in 2019 may indicate an expansion of the area in Norway with abundant odd-year pink salmon returns. In some small rivers in eastern Finnmark, between 1000 and 1500 pink salmon were fished out by local people in 2019, demonstrating the magnitude of the potential impact in terms of numbers of pink salmon. We cannot rule out that this will not happen over larger parts of Norway in the coming years. The even-year strain of pink salmon only occurs in low numbers in Russian rivers, as well as Norwegian, rivers. Adult pink salmon enter the rivers from early July, and spawning occurs in AugustSeptember. Spawning habitat requirements are like those of native salmonids: Atlantic salmon, brown trout, and Arctic charr. Spawning of pink salmon occurs earlier than the native salmonids, but observations in 2019 indicate a possible overlap with native salmonids in September in northern Norway. . Pink salmon eggs hatch in late winter or spring, and the alevins remain in the gravel until most of the yolk sac has been resorbed. Emerging fry are approximately 30 mm in length. ...................
Abstract
Global economic value of agriculture production resulting from animal pollination services has been estimated to be $235–$577 billion. This estimate is based on quantification of crops that are available at the global markets, and mainly originates from countries with precise information about quantities of agriculture production, exports, and imports. In contrast, knowledge about the contribution of pollinators to household food and income in small-scale farming at local and regional scales is still lacking, especially for developing countries where the availability of agricultural statistics is limited. Although the global decline in pollinator diversity and abundance has received much attention, relatively little effort has been directed towards understanding the role of pollinators in small-scale farming systems, which feed a substantial part of the world’s population. Here, we have assessed how local farmers in northern Tanzania depend on insect-pollinated crops for household food and income, and to what extent farmers are aware of the importance of insect pollinators and how they can conserve them. Our results show that local farmers in northern Tanzania derived their food and income from a wide range of crop plants, and that 67% of these crops depend on animal pollination to a moderate to essential degree. We also found that watermelon—for which pollination by insects is essential for yield—on average contributed nearly 25% of household income, and that watermelons were grown by 63% of the farmers. Our findings indicate that local farmers can increase their yields from animal pollinated crops by adopting more pollinator-friendly farming practices. Yet, we found that local farmers’ awareness of pollinators, and the ecosystem service they provide, was extremely low, and intentional actions to conserve or manage them were generally lacking. We therefore urge agriculture authorities in Tanzania to act to ensure that local farmers become aware of insect pollinators and their important role in agriculture production.
Abstract
Agricultural practices to improve yields in small‐scale farms in Africa usually focus on improving growing conditions for the crops by applying fertilizers, irrigation, and/or pesticides. This may, however, have limited effect on yield if the availability of effective pollinators is too low. In this study, we established an experiment to test whether soil fertility, soil moisture, and/or pollination was limiting watermelon (Citrullus lanatus) yields in Northern Tanzania. We subjected the experimental field to common farming practices while we treated selected plants with extrafertilizer applications, increased irrigation and/or extra pollination in a three‐way factorial experiment. One week before harvest, we assessed yield from each plant, quantified as the number of mature fruits and their weights. We also assessed fruit shape since this may affect the market price. For the first fruit ripening on each plant, we also assessed sugar content (brix) and flesh color as measures of fruit quality for human consumption. Extra pollination significantly increased the probability of a plant producing a second fruit of a size the farmer could sell at the market, and also the fruit sugar content, whereas additional fertilizer applications or increased irrigation did not improve yields. In addition, we did not find significant effects of increased fertilizer or watering on fruit sugar, weight, or color. We concluded that, insufficient pollination is limiting watermelon yields in our experiment and we suggest that this may be a common situation in sub‐Saharan Africa. It is therefore critically important that small‐scale farmers understand the role of pollinators and understand their importance for agricultural production. Agricultural policies to improve yields in developing countries should therefore also include measures to improve pollination services by giving education and advisory services to farmers on how to develop pollinator‐friendly habitats in agricultural landscapes.
Authors
Johan A. Stenberg Anders Nielsen Per Hans Micael Wendell Beatrix Alsanius Paal Krokene Christer Magnusson Mogens Nicolaisen Iben M. Thomsen Sandra A. I. Wright Trond RafossAbstract
ANDERcontrol with the predatory mite Amblyseius andersoni as the active organism is sought to be used as a biological control agent in Norway. ANDERcontrol is intended for use against different mites (such as the two-spotted, fruit-tree, and red spider mite, russet mite,cyclamen mite) and in horticultural crops such as fruits, berries, vegetables, and ornamental. VKM’s conclusions are as follows Prevalence, especially if the organism is found naturally in Norway: Amblyseius andersoni has not been observed in Norway. It has been observed, in low numbers, in southern Sweden and has the capability to enter diapause under unfavourable conditions which suggests the potential for establishing under Norwegian conditions. It is however, the view of VKM that it likely lacks the ability to survive and establish in areas with cold winters and chilly summers, as found in most parts of Norway under current climatic conditions. The potential of the organism for establishment and spread under Norwegian conditions specified for use in greenhouses and open field: The thermal preference of A. andersoni restricts its establishment, and the species has not been observed in Norway. The species is capable of entering diapause, but the lack of records, despite targeted surveys, makes it the opinion of VKM that it is unlikely that A. andersoni will be able to establish in outdoor areas in Norway. However, the lack of information on temperature tolerance of the species constitute an uncertainty factor. The risk of spread from greenhouses is low because no wind or vector are likely to carry the mites from the greenhouse to suitable outdoor habitats, and mite populations in greenhouses do not enter the more cold-tolerant diapause. All conclusions are uncertain due to lack of relevant information regarding the species’ climate tolerance. Any ambiguities regarding the taxonomy, which hampers risk assessment: There are no taxonomic challenges related to the assessment of A. andersoni. Assessment of the product and the organism with regard to possible health risk: VKM is unaware of reports where harm to humans by A. andersoni itself, or associated pathogenic organisms have been observed. Mites may however produce allergic reactions in sensitive individuals handling plant material with high numbers of individuals. There is reason to believe that this holds true also for A. andersoni. Key words: VKM, risk assessment, Norwegian Scientific Committee for Food and Environment, Norwegian Food Safety Authority, biological control, predatory mite
Authors
Johan A. Stenberg Anders Nielsen Per Hans Micael Wendell Beatrix Alsanius Paal Krokene Christer Magnusson Mogens Nicolaisen Iben M. Thomsen Sandra A. I. Wright Trond RafossAbstract
Atheta-System with the rove beetle Atheta coriaria (Kraatz 1856) as the active organism is sought to be used as a biocontrol agent for augmentation biological control in Norway. Atheta-System is intended for use against soil dwelling stages of fungus gnats (e.g. Bradysia paupera), shore flies (Scatella stagnalis), and thrips (e.g. Frankliniella occidentallis) in greenhouses, plastic tunnels, and other closed or controlled climate cultivations of horticultural crops, incl. soft-fruit crops, vegetables, ornamentals, and kitchen herbs. VKM’s conclusions are as follows Distribution, especially if the organism is found naturally in Norway Atheta coriaria is established (naturalized) in Norway since 1919 and has been reported numerous times from Agder in the South to Trøndelag in mid-Norway. The potential of the organism for establishment and spread under Norwegian conditions specified for use in greenhouses and open field The thermal thresholds of A. coriaria are not well-studied, but its current distribution in Southern and mid-Scandinavia shows that it tolerates relatively low winter temperatures, and that the Norwegian summer climate allows for successful reproduction. A. coriaria overwinters in the soil, which provides a relatively sheltered environment. Adults disperse rapidly by flying. All life stages can be vectored by humans – mainly by movement of soil and compost material. Thus, further spread northwards in Norway is predicted irrespective of additional introductions. It is unknown if it can enter diapause under greenhouse conditions. Any ambiguities regarding the taxonomy which hamper risk assessment There are no major taxonomic challenges related to the assessment of A. coriaria. Assessment of the product and the organism with regard to possible health risk VKM is unaware of reports of harm inflicted to humans by A. coriaria itself. Atheta-System comes with the cosmopolitan cheese mite (Tyrophagus putrescentiae), serving as food for A. coriaria. As with most mites, T. putrescentiae may induce allergic reactions in sensitive persons handling the product. Key words: VKM, risk assessment, Norwegian Scientific Committee for Food and Environment, Norwegian Food Safety Authority, biological control, rove beetle
Authors
Anders Nielsen Johan A. Stenberg Per Hans Micael Wendell Beatrix Alsanius Paal Krokene Christer Magnusson Mogens Nicolaisen Iben M. Thomsen Sandra A. I. Wright Trond RafossAbstract
The product Limonica, with the predatory mite Amblydromalus limonicus as the active organism, is sought to be used as a biological control agent in Norway. Limonica is intended for use against western flower thrips (Frankliniella occidentallis), other thrips (e.g. Thrips tabaci), spider mites and whiteflies (e.g. Trialeurodes, Aleyrodes and Bemisia spp.) in protected horticultural crops such as cucumber, sweet pepper, strawberry and ornamentals. The product is not recommended for greenhouse-grown tomatoes. VKM’s conclusions are as follows Distribution, especially if the organism is found naturally in Norway Amblydromalus limonicus has a very wide natural distribution, being reported from New Zealand, Australia South America, Central America, and North America as well as Hawaii. It has also recently established populations in crop productions and non-crop vegetation in Catalonia, North Eastern Spain. Amblydromalus limonicus have not been observed in Norway. The species seems not to have the capability to enter diapause under unfavourable conditions and it is the view of VKM that it likely lacks the ability to survive and establish in areas with cold winters and chilly summers, as found in most parts of Norway under current climatic conditions. The potential of the organism for establishment and spread under Norwegian conditions specified for use in greenhouses and open field The thermal preference of A. limonicus restricts its establishment, and the species has not been observed outdoors in Norway. As the species is incapable of entering diapause it is the opinion of VKM that it is unlikely that A. limonicus will be able to establish in outdoor areas in Norway. However, the lack of detailed information on temperature tolerance of the species constitutes an uncertainty factor. The risk of spread from greenhouses is low because no wind or vector are likely to carry the mites from the greenhouse to suitable outdoor habitats. However, mites that have escaped from a greenhouses to may spread in the nature. All conclusions are uncertain due to lack of relevant information regarding the species’ climate tolerance. Its origin and current distribution suggest that it cannot survive cold winters. Any ambiguities regarding taxonomy that hamper risk assessment There are no taxonomic challenges related to the assessment of A. limonicus. Assessment of the product and the organism with regard to possible health risks VKM Report 2020: 13 8 VKM is unaware of reports where harm to humans has been observed, whether by A. limonicus itself. Mites may, however, produce allergic reactions in sensitive individuals handling plant material with high numbers of individuals. There is reason to believe that this holds true also for A. limonicus. Key words: VKM, risk assessment, Norwegian Scientific Committee for Food and Environment, Norwegian Food Safety Authority, biological control, predatory mite
Authors
Eli Knispel Rueness Maria Gulbrandsen Asmyhr Hugo de Boer Katrine Eldegard Kjetil Hindar Lars Robert Hole Johanna Järnegren Kyrre Linné Kausrud Lawrence Richard Kirkendall Inger Elisabeth Måren Erlend Birkeland Nilsen Eva Bonsak Thorstad Gaute Velle Anders NielsenAbstract
Key words: Psittaciformes, CITES, Appendix I parrots, Status and trade assessment, Norwegian Scientific Committee for Food and Environment, Norwegian Environment Agency, VKM Background: Parrots are one of the most species-rich groups of birds of which the majority inhabits tropical and subtropical forests. Nearly one-third of parrots are threatened with extinction (IUCN categories CR, EN or VU) and more than half of the world’s parrot species are assumed to be decreasing in numbers. Parrots are popular pets on all continents, mainly due to their colourful feathers, their capacity to mimic the human voice, and their tolerance to life in captivity. More than 250 species have been traded internationally. Since the inception of CITES in 1975, trade of about 12 million live wild-sourced parrots has been registered. Currently, 55 parrot species are listed on CITES Appendix I (Norwegian CITES regulation list A) that includes the most endangered among CITES-listed animals and plants. In compliance with CITES, Norway only permits import for commercial purposes of Appendix I listed parrots bred in captivity in operations included in the Secretariat's Register (Resolution Conf. 12.10 (Rev. CoP15). Presently, 9 of the Appendix I parrot species are bred in such facilities. Import of Appendix I species to Norway requires permits both from the exporter’s CITES authority and the Norwegian Environment Agency (Norwegian CITES Management Authority). All legal transactions of CITES Appendix I listed species should be recorded in the UNEP World Conservation Monitoring Centre (UNEP-WCMC) Trade Database. However, discrepancies are common, demonstrating that the trade monitoring is not accurate. Moreover, several studies suggest that regardless of efforts to regulate trade, the global conservation situation for parrots may be worse than estimated by the IUCN species statuses. Even though habitat loss is the main threat to most parrot species, it has been suggested that priority should be given to conservation actions aimed at reducing the illegal capture of wild parrots for the pet trade. As Norway’s CITES Scientific Authority, the Norwegian Scientific Committee for Food and Environment (VKM) was assigned by the Norwegian Environment Agency to assess the status of populations and trade for Appendix I parrot species. Methods: As different trade patterns are typical for different geographic regions, the species were initially divided into three groups: Africa, Australasia and Central and South America. For species with commercial trade registered in the UNEP-WCMC trade database after year 2010 a full assessment was made. In addition, two species for which negative impact from illegal trade is suspected were also fully assessed. The assessments are based on the Norwegian Cites Regulation and Article III of the Convention and Resolution 16.7(Rev.CoP17). Information on the parrot species assessed in this report were gathered from the text accounts published by BirdLife International and Birds of the World as well as literature cited in the text. Results: VKM undertook full assessments of the population status and trade for 26 of the 55 CITES Appendix I species. The species assessments are presented as fact sheets. They each contain a brief summary of the species’ biology (name, taxonomy, distribution, life history, habitat and role in ecosystem), populations and trends, threats and conservation status, population surveillance and regulations, evaluation of legal/illegal trapping and trade, overall assessment of data quality and references. We found that the quantity, as well as quality, of the information available for the Appendix I parrot species varied much. This was the case for data on general biology, population size and trends and levels of illegal trade. For all of the 23 of species for which commercial trade was registered since 2010 in the UNEP-WCMC trade database discrepancies ........
Authors
Anders Nielsen Bjørn Arild Hatteland Martin Malmstrøm Ted von Proschwitz Gaute Velle Hugo de Boer Jan Ove Gjershaug Lawrence R. Kirkendall Eli Knispel Rueness Vigdis VandvikAbstract
No abstract has been registered
Authors
Hugo de Boer Maria Gulbrandsen Asmyhr Hanne Hegre Grundt Kjersti Sjøtun Hans K. Stenøien Jan Ove Gjershaug Kjetil Hindar Lawrence R. Kirkendall Nina Elisabeth Nagy Anders Nielsen Eli Knispel Rueness Odd Terje Sandlund Gaute VelleAbstract
No abstract has been registered
Authors
Anders Nielsen Merethe Aasmo Finne Maria Gulbrandsen Asmyhr Jan Ove Gjershaug Lawrence R. Kirkendall Vigdis Vandvik Gaute Velle Hugo de Boer Kjetil Hindar Nina Elisabeth Nagy Eli Knispel Rueness Odd Terje Sandlund Kjersti Sjøtun Hans K. StenøienAbstract
No abstract has been registered
Abstract
In Norway domestic sheep are mostly kept on mountain pastures over summer. Previous studies have shown that climate conditions affect the growth of mountain grazing lambs in contrasting ways. We analysed a data-set from the Tjøtta Research farm in northern Norway comprising weights and growth of 8696 lambs over 17 years. The lambs grazed coastal or a mountain pasture, 15 km apart. We found that the lambs grew faster when grazing the mountain pasture. Spring and integrated Normalized Difference Vegetation Index (NDVI) affected only the lambs grazing in the mountains. Winter conditions (North Atlantic Oscillation) and summer temperature had a positive effect on growth in both pastures while spring temperature and spring NDVI were important only in the mountains. The positive effect of spring NDVI suggests that the mountain pasture will produce bigger lambs under future climate warming, while the lambs on the coastal pasture will be less affected.
Authors
Anders Nielsen Nigel Yoccoz Geir Steinheim Geir Olve Storvik Yngve Rekdal Michael Angeloff Nathalie Pettorelli Øystein Holand Atle MysterudAbstract
No abstract has been registered
