Reintroductions are important tools for the conservation of individual species, but recently more attention has been paid to the restoration of ecosystem function, and to the importance of carrying out a full risk assessment prior to any reintroduction programme. In much of the Highlands of Scotland, wolves (Canis lupus) were eradicated by 1769, but there are currently proposals for them to be reintroduced. Their main wild prey if reintroduced would be red deer (Cervus elaphus). Red deer are themselves a contentious component of the Scottish landscape. They support a trophy hunting industry but are thought to be close to carrying capacity, and are believed to have a considerable economic and ecological impact. High deer densities hamper attempts to reforest, reduce bird densities and compete with livestock for grazing. Here, we examine the probable consequences for the red deer population of reintroducing wolves into the Scottish Highlands using a structured Markov predator-prey model. Our simulations suggest that reintroducing wolves is likely to generate conservation benefits by lowering deer densities. It would also free deer estates from the financial burden of costly hind culls, which are required in order to achieve the Deer Commission for Scotland's target deer densities. However, a reintroduced wolf population would also carry costs, particularly through increased livestock mortality. We investigated perceptions of the costs and benefits of wolf reintroductions among rural and urban communities in Scotland and found that the public are generally positive to the idea. Farmers hold more negative attitudes, but far less negative than the organizations that represent them.

Woodlands can reduce the risk of rainfall-generated flooding through increased interception, soil infiltration and available storage. Despite growing evidence, there is still low confidence in using woodlands as a flood mitigation method due to limited empirical data, particularly for broadleaf woodlands. We measured soil properties and streamflow for nine small (<0.2 km 2 ) upland catchments and compared mature semi-natural broadleaf woodland where no stock grazing occurs to pasture with varied grazing intensity. We compared streamflow across 28 storm events including a 1 in 10-year event, two 1 in 4-year events and five 1 in 1.5-year events, identified over a 13-month period. We found that semi-natural broadleaf woodlands reduce specific peak discharge by 23%-60% and peak runoff coefficients by 30%-60% compared with pasture. Response to storm events took 14-50% longer in woodland compared to pasture. These differences in flood response are partly explained by more permeable woodland soils, 11-20 times greater than pasture soil. The more muted response of wooded catchments to storm events is consistent across the storms investigated, including Storm Ciara, a 1 in 10-year event. Our analysis strengthens the argument that semi-natural woodlands can reduce rainfall-generated flooding contributing to the evidence base for natural flood management.catchment-based flood management, natural flood management, pasture, soil permeability, woodland | INTRODUCTIONOver the past three decades the frequency of flood events has increased across the UK (Rogger et al., 2017) and worldwide (Hall et al., 2014;Kundzewicz et al., 2014;Wingfield et al., 2019). In England, floods cause damages of £1.1 billion annually with one in six properties at risk from flooding (Priestley, 2017). This risk is expected to further increase under future climate change (Iacob et al., 2017).Because of recent floods, there is a growing interest in the use of 'soft-engineered' flood mitigation schemes (Dadson et al., 2017;Stevens et al., 2016). Natural Flood Management (NFM), also referred to as working with natural processes or nature-based solutions (Seddon et al., 2020), is an approach to flood management that seeks to work with natural processes to enhance the flood regulatory capacity of a catchment. Often these approaches also provide ecosystem services such as pollution assimilation, habitat creation and carbon storage (Hankin et al., 2017). NFM approaches may include the

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The increased frequency of flood events has motivated interest in natural flood management (NFM), in particular the potential for woodlands to reduce flooding. Woodlands can reduce the risk of rainfall-generated flooding through increased interception, soil infiltration, and available storage. Despite growing evidence, there is still low confidence in woodlands as a flood mitigation method due to limited empirical data available, particularly for semi-natural woodlands. We established a correlation catchment study in Haweswater, Cumbria, UK. Nine small upland catchments, each less than 0.2 km2 in area, were established on semi-natural broadleaf woodland sites where no stock grazing occurs or pasture with varied grazing intensity. At each site soil characteristics were investigated, namely soil moisture, permeability and bulk density. In addition, a v-notch weir was installed within in each catchment to calculate flow. The specific peak discharge (SPD), peak runoff coefficient, volume runoff coefficient and time taken to flow response was determined at each site for 28 storm events, of up to 205 mm, identified over a 13-month period. We found that semi-natural woodland reduced SPD by 33-52 % compared with pasture, reducing SPD by 36 % during larger storms (> 1 mm/hr peak discharge). Woodland reduced the peak runoff coefficient by 31-52 % and the volume runoff coefficient by 13-22 % compared to pasture. Additionally, response to storm events took 1-4 hours longer in woodland. These differences in flood response can be somewhat explained by the more permeable woodland soils, 4.6 times greater than pasture soil. Our analysis strengthens the argument that woodlands can reduce rainfall-generated flooding as a land use management method of NFM. Data collected here should be used to inform the parameters in flood prediction models and contribute to the evidence base for NFM.