8 research outputs found

    The use of historical collections to estimate population trends: a case study using Swedish longhorn beetles (Coleoptera: Cerambycidae)

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    Long term data to estimate population trends among species are generally lacking. However, Natural History Collections (NHCs) can provide such information, but may suffer from biases due to varying sampling effort. To analyze population trends and range-abundance dynamics of Swedish longhorn beetles (Coleoptera: Cerambycidae), we used collections of 108 species stretching over 100 years. We controlled for varying sampling effort by using the total number of database records as a reference for non-red-listed species. Because the general frequency of red-listed species increased over time, a separate estimate of sampling effort was used for that group. We observed large interspecific variation in population changes, from declines of 60\% to several hundred percent increases. Most species showed stable or increasing ranges, whereas few seemed to decline in range. Among increasing species, rare species seemed to expand their range more than common species did, but this pattern was not observed in declining species. Historically, rare species did not seem to be at larger risk of local extinction, and population declines were mostly due to lower population density and not loss of sub-populations. We also evaluated the species' declines under IUCN red-list criterion A, and four currently not red-listed species meet the suggested threshold for Near Threatened (NT). The results also suggested that species' declines may be overlooked if estimated only from changes in species range

    Swedish LifeWatch ─ a biodiversity infrastructure integrating and reusing data from citizen science, monitoring and research

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    With continued pressure on biodiversity and ever-growing conflicts with human development, qualified systems for scenario modelling, impact assessment and decision support are urgently needed. Such systems must be able to integrate complex models and information from many sources and do so in a flexible and transparent way. To that end, as well as for other complicated and data-intensive biodiversity research purposes, the concept of LifeWatch has emerged. The idea of LifeWatch is to construct e-infrastructure and virtual laboratories by integrating large data sources, computational capacities, and tools for analysis and modelling in an open, serviceoriented architecture. To be efficient and accurate, a continuous inflow of large quantities of data is essential. However, even with new techniques, government-funded monitoring data and research data will not feed the system with up-to-date species information of sufficient scale and resolution. To fill this void, skilled amateur observers (citizen scientists) can contribute to a very valuable extent. After a preparatory phase, a Swedish LifeWatch (SLW) consortium was initiated in 2011. Swedish LifeWatch developed an infrastructure where all components are accessible through open web services. At the SLW Analysis portal, different formats of species and environmental data can be accessed instantly, and integrated, analysed, visualized and downloaded at selected temporal, spatial or taxonomic scales. Swedish LifeWatch currently provides 46 million species observations from eight different databases, all harmonized according to standardized formats and the Dyntaxa taxonomic backbone database. Almost 40 million of these observations were provided by citizens through the online reporting system named the Species Observation System (SOS) or Artportalen. This paper describes this system, as well as the incentives that make it so successful. The citizen science data in the SOS are accessible, together with data from research and monitoring, in the SLW infrastructure, making the latter a powerful instrument for large-scale data extraction, visualization and analysis

    TillstÄnd och trender för arter och deras livsmiljöer

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    2015 Ärs upplaga av den svenska rödlistan Àr den fjÀrde i ordningen. Den Àr baserad pÄ IUCN:s rödlistningskriterier och revideras vart femte Är. I rödlistan bedöms risken som enskilda arter av djur, vÀxter och svampar löper att försvinna frÄn Sverige. Bedömningen utförs av ArtDatabankens medarbetare i samverkan med över 100 externa experter, indelade i 14 expertkommittéer för olika organismgrupper. Under arbetet med 2015 Ärs rödlista har tillstÄnd och trender bedömts för 21 600 arter och 1 318 lÀgre taxa (apomiktiska arter, underarter och varieteter), sammanlagt ca 22 900 taxa. Av de bedömda arterna klassificerades 2 029 som hotade (kategorierna CR, EN och VU) och 4 273 som rödlistade (inkluderar Àven kategorierna NT, RE och DD). FörhÄllandet mellan antalet rödlistade och antalet bedömda arter ar 19,8 %, vilket Àr ungefÀr samma vÀrde som 2010 och 2005. I denna rapport jÀmförs antalet och andelen rödlistade arter mellan olika organismgrupper, biotoper, substrat och pÄverkansfaktorer. Texten ar indelad i en allmÀn del och Ätta kapitel inriktade pÄ olika landskapstyper. Landskapstyperna utgör en grov indelning av landets miljöer enligt följande kategorier: Skog, Jordbrukslandskap, Urbana miljöer, FjÀll, VÄtmarker, Sötvatten, HavsstrÀnder och Havsmiljöer. Skogen och jordbrukslandskapet Àr de artrikaste landskapstyperna med 1 800 respektive 1 400 arter som har en stark anknytning dit, och ytterligare flera hundra arter som förekommer dÀr mer sporadiskt. De faktorer som pÄverkar flest rödlistade arter i Sverige Àr skogsavverkning och igenvÀxning, som bÄda utgör ett hot mot vardera ca 30 % av de rödlistade arterna. Avverkning minskar arealen av skog dÀr naturliga strukturer och naturlig dynamik upprÀtthÄlls, och den orsakar dÀrmed förlust av livsmiljöer. IgenvÀxning orsakas av ett antal faktorer, bland annat upphörande hÀvd (bete och slÄtter), gödsling, trÀdplantering och brist pÄ naturliga störningsregimer som t.ex. regelbundna översvÀmningar kring vattendrag och sjöar. Andra viktiga pÄverkansfaktorer Àr fiske, torrlÀggning av vÄtmarker, tillbakagÄng hos vÀrdarter (frÀmst alm och ask som drabbats av invasiva svampsjukdomar), klimatförÀndringar och konkurrens frÄn invasiva arter. IUCN:s rödlisteindex berÀknas för ett urval av de bedömda organismgrupperna. Rödlisteindex visar att skillnaderna mellan rödlistorna frÄn 2000, 2005, 2010 och 2015 Àr smÄ. Ett par undantag finns dock. Groddjur och stora dÀggdjur har fÄtt en nÄgot förbÀttrad situation sedan 2000. Totalt förefaller det ÀndÄ som att trycket mot Sveriges artstock har förblivit relativt konstant under de senaste 15 Ären

    Completing Linnaeus's inventory of the Swedish insect fauna: Only 5,000 species left?

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    Despite more than 250 years of taxonomic research, we still have only a vague idea about the true size and composition of the faunas and floras of the planet. Many biodiversity inventories provide limited insight because they focus on a small taxonomic subsample or a tiny geographic area. Here, we report on the size and composition of the Swedish insect fauna, thought to represent roughly half of the diversity of multicellular life in one of the largest European countries. Our results are based on more than a decade of data from the Swedish Taxonomy Initiative and its massive inventory of the country's insect fauna, the Swedish Malaise Trap Project The fauna is considered one of the best known in the world, but the initiative has nevertheless revealed a surprising amount of hidden diversity: more than 3,000 new species (301 new to science) have been documented so far. Here, we use three independent methods to analyze the true size and composition of the fauna at the family or subfamily level: (1) assessments by experts who have been working on the most poorly known groups in the fauna; (2) estimates based on the proportion of new species discovered in the Malaise trap inventory; and (3) extrapolations based on species abundance and incidence data from the inventory. For the last method, we develop a new estimator, the combined non-parametric estimator, which we show is less sensitive to poor coverage of the species pool than other popular estimators. The three methods converge on similar estimates of the size and composition of the fauna, suggesting that it comprises around 33,000 species. Of those, 8,600 (26%) were unknown at the start of the inventory and 5,000 (15%) still await discovery. We analyze the taxonomic and ecological composition of the estimated fauna, and show that most of the new species belong to Hymenoptera and Diptera groups that are decomposers or parasitoids. Thus, current knowledge of the Swedish insect fauna is strongly biased taxonomically and ecologically, and we show that similar but even stronger biases have distorted our understanding of the fauna in the past. We analyze latitudinal gradients in the size and composition of known European insect faunas and show that several of the patterns contradict the Swedish data, presumably due to similar knowledge biases. Addressing these biases is critical in understanding insect biomes and the ecosystem services they provide. Our results emphasize the need to broaden the taxonomic scope of current insect monitoring efforts, a task that is all the more urgent as recent studies indicate a possible worldwide decline in insect faunas

    A genus new to Norway and the distribution of Protaphidius wissmannii (Ratzeburg, 1848) (Hymenoptera, Braconidae; Aphidiinae) in Scandinavia, a parasitoid of ant-attended aphids on tree trunks

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    The genus Protaphidius Ashmead, 1900 and it's only species in Europe, P. wissmannii (Ratzeburg, 1848) are here reported new to Norway. Protaphidius wissmannii is a parasitoid of giant aphids of the genus Stomaphis Linnaeus, 1758. The first records for Sweden, the Netherlands and Bulgaria are included and the distribution in Scandinavia is briefly discussed. A few additional European records belonging to the naturalis collection in Leiden, are also reported. Stomaphis longirostris (Fabricius, 1787) is a new host record. Hymenoptera, Braconidae, Aphidiinae, Protaphidius wissmannii, Stomaphis, parasitoid, FormicidaepublishedVersio

    On the Dynamics of Structured Argumentation:Modeling Changes in Default Justification Logic

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    This paper studies information changes in default justification logic with argumentation semantics. We introduce dynamic operators that combine belief revision and default theory tools to define both prioritized and non-prioritized operations of contraction, expansion and revision for justification logic-based default theories. This combination enriches both default logics and belief revision techniques. We argue that the kind of attack called "undermining" amounts to those operations that contract a knowledge base by an attacked formula
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