Impact of Management on Avian Communities in the Scottish Highlands

Resilience of temperate peatland vegetation communities to wildfire depends upon burn severity and pre-fire species composition

Peatland ecosystems are of global conservation and environmental importance storing globally significant amounts of ancient carbon, regulating regional temperatures and hydrological regimes, and supporting unique biodiversity. Livestock grazing, land-use change, drainage, nutrient and acid deposition, and wildfire threaten the composition and function of many peatlands including those in the uplands of the United Kingdom. Presently, little is known about either the short- or long-term effects of wildfires within these systems in the UK. Our study aimed to evaluate how plant communities respond to wildfires across a range of vegetation communities, soil types, and burn severities. We evaluated wildfire burn severity using the ground-based Composite Burn Index adapted for treeless peatlands. Using paired burned-unburned plots, we quantified differences in the abundance of plant families and functional groups, vegetation diversity, and community composition. Multivariate differences in composition between burned and unburned areas were used as an index of community resilience to fire. Plots in heathland communities with shallow organic soils burned at the highest severities and had the greatest reductions in plant diversity and richness. There were significant declines in plot-scale species richness and diversity with increasing burn severity. Graminoids were resilient to fire whilst Ericaceae tended to increase with higher severity. Bryophyte composition was substantially altered-pleurocarpous species declined and acrocarpous species increased with greater burn severity. Community resilience was related to ground layer burn severity with higher burn severity driving greater changes in communities. Wildfire effects on temperate peatlands are a function of fire weather and site environmental and ecological characteristics. Management policy should ensure that the risk of severe wildfires is mitigated to protect ecosystem function and biodiversity. This will require system-specific fire management prescriptions across the gradient of peatland soil and vegetation types.

The influence of different aspects of grouse moorland management on nontarget bird assemblages

Conflict between stakeholders with opposing interests can hamper biodiversity conservation. When conflicts become entrenched, evidence from applied ecology can reveal new ways forward for their management. In particular, where disagreement exists over the efficacy or ethics of management actions, research clarifying the uncertain impacts of management on wildlife can move debates forwards to conciliation.Here, we explore a case-study of entrenched conflict where uncertainty exists over the impacts of multiple management actions: namely, moorlands managed for the shooting of red grouse (willow ptarmigan) Lagopus lagopus in the United Kingdom (UK). Debate over how UK moorlands should be managed is increasingly polarized. We evaluate, for the first time at a regional scale, the relative impacts of two major moorland management practices-predator control and heather burning-on nontarget bird species of conservation concern.Birds were surveyed on 18 estates across Northern England and Southeast Scotland. Sites ranged from intensively managed grouse moors to moorland sites with no management for grouse shooting. We hypothesised that both targeted predator control and burning regimes would enhance ground-nesting wader numbers and, as a consequence of this, and of increased grouse numbers, nontarget avian predators should also be more abundant on heavily managed sites.There were positive associations between predator control and the abundance of the three most widespread species of ground-nesting wader: strong effects for European golden plover Pluvialis apricaria and Eurasian curlew Numenius arquata and, less strongly, for common snipe Gallinago gallinago. These effects saturated at low levels of predator control. Evidence for effects of burning was much weaker. We found no evidence of enhanced numbers of nontarget predators on heavily managed sites.

Effects of Land Use Intensification on Avian Predator Assemblages: A Comparison of Landscapes with Different Histories in Northern Europe

Land use and landcover change alter the ability of habitat networks to maintain viable species populations. While their effects on the quality, amount and patterns of landcover patches are commonly studied, how they affect ecological processes, such as predation on focal species remains neglected. This macroecological study tests the hypothesis that predator assemblages are affected by land use intensity linked to different socio-economic contexts. We measured the distribution and abundance of two avian predator groups (generalist corvid birds and specialist raptors), and proxy variables that mirror their food resources, at three spatial scales in northern Europe’s West and East. In total, we made 900 survey counts for avian predators and their resources in six landcover strata throughout five landscapes and analyzed their relationships. The abundance of omnivorous corvid birds was associated with the number of anthropogenic food resources. Thus, corvid birds were most common in the urban and agricultural landcovers, and where forest cover was low. Corvid bird abundance, and availability of their resources, increased with increasing land use intensity. Raptors were less abundant than corvid birds and most common in semi-natural grasslands. The number of raptor species increased with decreasing land use intensity. This study shows that the abundance and composition of avian predator species must be understood to maintain functional habitat networks.

How to reconcile wood production and biodiversity conservation? The Pan-European boreal forest history gradient as an "experiment"

There are currently competing demands on Europe's forests and the finite resources and services that they can offer. Forestry intensification that aims at mitigating climate change and biodiversity conservation is one example. Whether or not these two objectives compete can be evaluated by comparative studies of forest landscapes with different histories. We test the hypothesis that indicators of wood production and biodiversity conservation are inversely related in a gradient of long to short forestry intensification histories. Forest management data containing stand age, volume and tree species were used to model the opportunity for wood production and biodiversity conservation in five north European forest regions representing a gradient in landscape history from very long in the West and short in the East. Wood production indicators captured the supply of coniferous wood and total biomass, as well as current accessibility by transport infrastructure. Biodiversity conservation indicators were based on modelling habitat network functionality for focal bird species dependent on different combinations of stand age and tree species composition representing naturally dynamic forests. In each region we randomly sampled 25 individual 100-km² areas with contiguous forest cover. Regarding wood production, Sweden's Bergslagen region had the largest areas of coniferous wood, followed by Vitebsk in Belarus and Zemgale in Latvia. NW Russia's case study regions in Pskov and Komi had the lowest values, except for the biomass indicator. The addition of forest accessibility for transportation made the Belarusian and Swedish study region most suitable for wood and biomass production, followed by Latvia and two study regions in NW Russian. Regarding biodiversity conservation, the overall rank among regions was opposite. Mixed and deciduous habitats were functional in Russia, Belarus and Latvia. Old Scots pine and Norway spruce habitats were only functional in Komi. Thus, different regional forest histories provide different challenges in terms of satisfying both wood production and biodiversity conservation objectives in a forest management unit. These regional differences in northern Europe create opportunities for exchanging experiences among different regional contexts about how to achieve both objectives. We discuss this in the context of land-sharing versus land-sparing.