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Arthropods are often ignored or under-sampled in biodiversity and conservation assessments because of their large diversity, small size and lack of taxonomic guides. Rapid biodiversity assessment programmes have been established to assess these groups accurately. A COBRA (Conservation Oriented Biodiversity Rapid Assessment) protocol consists of an intense sampling of a habitat using the optimal combination of sampling methods. We set a basis for future protocols of measuring spider biodiversity in exotic pastures in New Zealand. Overall, 28 spider species were collected. There was variation in species discovery for each collection method, i.e. pitfall traps (86.6% of total species found), ground hand collection (95.4%), suction sampling (85.7%), and sweeping (25%). The various collection methods were complementary in species that were found. Of the four sampling methods used pitfall traps and ground hand collection were far more efficient at collecting spider species in pastures per sample. These findings are relevant for the future development of these protocols and ultimately, these tools will be used for assessing and monitoring biodiversity on farms and the impacts of farming methods. [ABSTRACT FROM AUTHOR]

Abstract: Restoration programs for human-disturbed ecosystems rely on a good understanding of how recovery occurs. This requires elucidating the underlying succession process, which depends on species adaptations, their interactions, and the spatiotemporal characteristics of the disturbance. Using spiders, we aim to identify the drivers of succession after burning, commonly used in New Zealand native tussock grasslands, test the hypothesis of post-burning dominance of generalists over specialists, and test the presumption that managed summer burns are more detrimental than spring burns. We established a 7-year experiment, with spring and summer burn treatments and unburned control plots, and sampled annually before and after the burning. We identified changes in spider assemblages and their drivers using clustering and indicator value analyses, and we analysed the response of spider diversity and taxa through linear mixed-effect models. In both spring and summer burns, functional groups and diversity decreased and the density of individuals of generalist species increased. However, spring and summer burn treatments showed no differences in spider diversity and composition. We found evidence that adaptations, such as habitat specificity and dispersal ability, determine the recovery of spider communities, and we suggest a set of indicators for monitoring programs. Time of burning may interact with factors like flammability and fire intensity, reducing differences in the effects of burning between seasons. We recommend planning burns for wet seasons as they are easier to control. To facilitate recolonisation by rare species of spiders of tussock grasslands, we suggest maintaining unburned areas that represent different vegetation types. [Copyright &y& Elsevier]

. 1. Physical structure and species composition of vegetation determine spider diversity through habitat availability. Here, we assess, for the first time, the role of plant structure on spider communities in New Zealand native alpine tussock grasslands. We investigate the specific associations between spider assemblages and plant communities and test the hypothesis that spider diversity increases with plant diversity and tussock cover. 2. Spiders were sampled using density- and abundance-activity-dependent methods. Data on physical characteristics and species composition of plants revealed gradients in vegetation, driven by distinct intra-ecosystem plant communities. Effects of vegetation on spider diversity and composition were assessed through linear mixed-effects models. Redundancy analysis was used to determine and visualise the spider species-level response to gradients in plant compositions. 3. There was a positive relationship between plant diversity and spider diversity, while the effects of tussock cover varied with spider taxa. Overall, physical structure and species composition of vegetation had effects on the abundance of a similar number of spider species and families. 4. Gradients in vegetation were matched to gradients in spider communities, whose diversity and composition varied according to their habitat preference. The family Orsolobidae was associated with wetland vegetation, and Linyphiidae with shrubs. The abundance of certain spider families and species, such as Lycosidae and Anoteropsis hilaris, was consistently affected by vegetation. 5. Environmental factors, such as soil moisture, may affect plant species composition and physical structure in tussock grasslands, which in turn determine spider assemblages. Lycosidae were identified as potential indicators of structural changes in tussock grassland plants and could be valuable for ecological monitoring in conservation management. [ABSTRACT FROM AUTHOR]