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Substratpreferenser hos Crossocalyx hellerianus i svenska barrskogar : är skoglig kontinuitet en viktig faktor?Kvarnsudde, David January 2020 (has links)
In recent time, forests in Sweden have lost habitat quality in the loss of deadwood due to the practices in productions forestry. This means that substrates for epixylic species has decreased both in quality and quantity. The aim with this study was to find which preferences the epixylic liverwort, Crossocalyx hellerianus has on its substrate and environment. C. hellerianus requires coarse logs with rotten wood, which usually is more available in forests with long forest continuity. This study was performed to see if forest continuity, isolation of habitats and if the substrate was of significance for a demanding species such as C. hellerianus. The study was performed in six sites and in each site several 50x10 meter transects were surveyed for logs. Each log was measured for diameter, sun exposure, ground contact, stage of decay and if the log was colonized by C. hellerianus. The result showed that C. hellerianus preferred coarser logs and that the species only appeared on an intermediate or later stage of decay. A high forest continuity and low habitat isolation turned out to be positive factors for the abundance of C. hellerianus
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Beteendesyndrom hos blankål (Anguilla anguilla): aktivitet och respons på främmande objekt i en artificiell miljö / Behavioural syndromes in silver eel (Anguilla anguilla): activity and response to novel objects in an artificial environmentIngelman Åslund, Trollet January 2020 (has links)
Ökad kunskap om djurs beteendesyndrom kan möjliggöra förbättrade bevarandeåtgärder för hotade arter. I den här studien genomgick 108 blankålar (Anguilla anguilla) två beteendetester; “open-field test” och “novel-object test”. Ålars morfologi och val av föda, habitat och dygnsaktivitet har i tidigare studier visats hänga ihop. I den här studien undersökte jag om det fanns något samband mellan ålarnas morfologi, aktivitet samt respons på främmande föremål. De ålar som var mest aktiva under open-field-testet var också de ålar som visade störst intresse för det främmande föremålet i novel-object-testet. Det fanns dock inte något samband mellan morfologi och aktivitet eller mellan morfologi och respons på främmande föremål. Detta innebär att ett utforskande och djärvt beteendesyndrom har upptäckts hos vissa av ålarna, medan den bakomliggande faktorn fortsätter vara okänd. / Increased knowledge of behavioural syndromes may contribute to enhancing our conservation methods for endangered species. In this study, the behavior of 108 silver eels (Anguilla anguilla) was assessed in two assays: an open-field test and a novel-object test. Eel morphology and diel activity as well as diet and habitat use have previously been shown to correlate with each other. In this study, I investigated the potential relationship between the morphology, activity and response to a novel object. The most active eels during the open-field test were also the ones that expressed the most interest for the novel object. There was, however, no correlation between morphology and activity or morphology and response to the novel object. This means an exploring and bold behaviour syndrome was discovered amongst some of the eels, whilst the underlying cause remains unknown.
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