The biodiversity audit approach challenges regional priorities and identifies a mismatch in conservation

1. Despite a strong uptake of evidence-based approaches, conservation often proceeds from a grossly incomplete understanding of species priorities. To optimize conservation impact within a biogeographical region, quantitative knowledge is needed of the species present, which should be prioritized, and the management interventions these require. The next challenge is to avoid a proliferation of competing species plans, or conversely, a lack of detail within generic habitat-based approaches. 2. We present a methodology for biodiversity auditing. We quantified regional biodiversity by systematically collating available species records, allowing objective prioritization. We collated autecological information to integrate multiple species into management guilds with shared requirements, providing evidence-based guidance for regional conservation. 3. For two regions of Eastern England, Breckland (2300 km^2 ) and The Broads (2000 km^2 ), we collated 083 and 15-million records, respectively. Numbers of species (12 845 and 11 067) and priority species (rare, threatened, designated or regionally restricted: 2097 and 1519, respectively) were orders of magnitude greater than previously recognized. Regional specialists, with a UK range largely or entirely restricted to the region, were poorly recognized posing a risk of regional homogenization. 4. A large body of autecological information existed for priority species and collating this allowed us to define cross-taxa management guilds. Numbers of priority species requiring different combinations of ecological processes and conditions were not matched by current conservation practice in Breckland. For example, the current agri-environment agreements for designated grass heaths potentially catered for only 15% of the 542 priority species and 21% of 47 regional specialists that could potentially benefit from evidence-based management. A focus on vegetation composition rather than the ecological requirements of priority species underpinned this failure. 5. Synthesis and applications. The biodiversity audit approach provides an objective model for prioritization and cost-effective conservation, applicable to regions of Europe where biodiversity has been well characterized. By using this approach to collate available information, management guilds with similar requirements can be defined across taxa, providing evidence-based guidance for regional conservatio

Achieving landscape-scale deer management for biodiversity conservation: The need to consider sources and sinks

Hyper-herbivory following predator removal is a global issue. Across North America and Europe, increasing deer numbers are affecting biodiversity and human epidemiology, but effectiveness of deer management in heterogeneous landscapes remains poorly understood. In forest habitats in Europe, deer numbers are rarely assessed and management is mainly based on impacts. Even where managed areas achieve stable or improving impact levels, the extent to which they act as sinks or persist as sources exporting deer to the wider landscape remains unknown. We present a framework to quantify effectiveness of deer management at the landscape scale. Applied across 234 km2 of Eastern England, we assessed management of invasive Reeve’s muntjac (Muntiacus reevesi) and native roe (Capreolus capreolus), measuring deer density (using thermal imaging distance transects 780 km/year), fertility, neonatal survival, and culling to quantify source-sink dynamics over 2008–2010. Despite management that removed 23–40% of the annual population, 1,287 (95% CI: 289–2,680) muntjac and 585 (454–1,533) roe deer dispersed annually into the wider landscape, consistent with their ongoing range expansion. For roe deer, culled individuals comprised fewer young deer than predicted by a Leslie matrix model assuming a closed population, consistent with agedependent emigration. In this landscape, for roe and muntjac, an annual cull of at least 60% and 53%, respectively, is required to offset annual production. Failure to quantify deer numbers and productivity has allowed high density populations to persist as regional sources contributing to range expansion, despite deliberative management programs, and without recognition by managers who considered numbers and impacts to be stable. Reversing an unfavorable condition of woodland biodiversity requires appropriate culls across large contiguous areas, supported by knowledge of deer numbers and fertility

Survival rates of captive-bred Asian Houbara Chlamydotis macqueenii in a hunted migratory population

Asian Houbara Chlamydotis macqueenii numbers are declining owing to unsustainable levels of hunting and poaching, with the main conservation response being population reinforcement through the release of captive-bred birds. We assessed the contribution of captive breeding to the species’ conservation by examining the fates of 65 captive-bred birds fitted with satellite transmitters and released during spring (March–May) and autumn (August) into breeding habitat in Uzbekistan. Of the released birds, 58.5% survived to October, the month favoured by Emirati hunters in Uzbekistan, but only 10.8% of those released survived the winter to return as sub-adults next spring. To mitigate and compensate the loss of wild adults to hunting, the number of released birds needs to be an order of magnitude higher than hunting quotas (with a release of between 1640-1920 required for a hypothetical quota of 200), indicating that releases may be costly and do not remove the need for a biologically determined sustainable hunting quota

Recreational use of the countryside: No evidence that high nature value enhances a key ecosystem service

In Western Europe, recreational amenity is presented as an important cultural ecosystem service that, along with other values, helps justify policies to conserve biodiversity. However, whether recreational use by the public is enhanced at protected areas designated for nature conservation is unknown. This is the first study to model outdoor recreation at a national scale, examining habitat preferences with statutory designation (Site of Special Scientific Interest) as an indicator of nature conservation importance. Models were based on a massive, three year national household survey providing spatially-referenced recreational visits to the natural environment. Site characteristics including land cover were compared between these observed visit sites (n = 31,502) and randomly chosen control sites (n = 63,000). Recreationists preferred areas of coast, freshwater, broadleaved woodland and higher densities of footpaths and avoided arable, coniferous woodland and lowland heath. Although conservation designation offers similar or greater public access than undesignated areas of the same habitat, statutory designation decreased the probability of visitation to coastal and freshwater sites and gave no effect for broadleaved woodland. Thus general recreational use by the public did not represent an important ecosystem service of protected high-nature-value areas, so that intrinsic and existence values remain as the primary justifications for conservation of high nature value areas. Management of ‘green infrastructure’ sites of lower conservation value that offer desirable habitats and enhanced provision of footpaths, could mitigate recreational impacts on nearby valuable conservation areas

Arthropod traits and assemblages differ between core patches, transient stepping-stones and landscape corridors

Context Restoring landscape connectivity can mitigate fragmentation and improve population resilience, but functional equivalence of contrasting elements is poorly understood. Evaluating biodiversity outcomes requires examining assemblage-responses across contrasting taxa. Objectives We compared arthropod species and trait composition between contrasting open-habitat network elements: core patches, corridors (allowing individual dispersal and population percolation), and transient stepping-stones (potentially enhancing metapopulation dynamics). Methods Carabids and spiders were sampled from core patches of grass-heath habitat (n = 24 locations across eight sites), corridors (trackways, n = 15) and recently-replanted clear-fells (transient patches, n = 19) set in a forest matrix impermeable to openhabitat arthropods. Species and trait (habitat association, diet, body size, dispersal ability) composition were compared by ordination and fourth corner analyses. Results Each network element supported distinct arthropod assemblages with differing functional trait composition. Core patches were dominated by specialist dry-open habitat species while generalist and woodland species contributed to assemblages in connectivity elements. Nevertheless, transient patches (and to a lesser degree, corridors) supported dry-open species characteristic of the focal grass-heath sites. Trait associations differed markedly among the three elements. Dispersal mechanisms and their correlates differed between taxa, but dry-open species in transient patches were characterised by traits favouring dispersal (large running hunter spiders and large, winged, herbivorous carabids), in contrast to wingless carabids in corridors. Conclusions Core patches, dispersal corridors and transient stepping-stones are not functionally interchangeable within this system. Semi-natural core patches supported a filtered subset of the regional fauna. Evidence for enhanced connectivity through percolation (corridors) or meta-population dynamics (stepping stones) differed between the two taxa

What does ‘traditional’ management really mean?

In spite of the increases in our knowledge achieved over the past half century, not least through the contributions of Oliver Rackham, we still know relatively little about historic land use practices or their ecological outcomes. By the time the characteristics of particular habitat types were first recorded in the mid-late nineteenth century, by Richard Jefferies for example, they were already changing fast, as a consequence of agricultural modernisation, industrialisation, and unprecedented population growth. Yet even before all of these far-reaching developments, land management systems had changed radically over time, and had varied from place to place, producing a constellation of landscape types that were considerably more unstable and variable than those produced by modern conservation methods (Fuller et al. 2017). Population fluctuated both locally and nationally, and farming varied in response to markets in meat and grain or the requirements of local and national industries. Throughout western Europe, semi-natural habitats are often classified according to their past exploitation (e.g. Tansley 1939; Ratcliffe 1977; EC 1992), and within our surviving fragments of semi-natural vegetation, conservation management generally aims to continue the ‘traditional’ practices (those of pre-industrial [c. 1200-1750] land management systems) which originally contributed to their character. While these traditional practices have created a number of the habitats that we value today, our ancestors were, of course, not carrying them out with any aim of increasing biodiversity. The wildlife value of traditional landscapes came as a fortuitous by-product of intensive land stripping, vegetation clearance and exploitation by man; characterised by dynamic nested heterogeneity, compatible to a sizeable subset of potential Biodiversity. However, while current management of wildlife habitats may attempt to mimic aspects of ‘traditional’ practices, it arguably simplifies their character and thus, as the ‘State of Nature Report’ (Hayhow et al. 2016) has shown, is failing to sustain the species with which they are particularly associated. Indeed, it is likely that, to a significant extent, the conviction that ‘traditional’ management systems are insufficient for conservation is based on a poor understanding of what these actually involved, and of what they achieved. The management of individual land parcels, including those that we think of today as ‘semi-natural’, was far from static, and this raises important questions about how we can restore them to a meaningful ‘baseline’. More importantly, in failing to understand the real processes which made particular suites of species characteristic of particular places, we may be unable to sustain these into the future. In this article we elucidate the real character of past management systems, and suggest how the principles they embody can be used to develop innovative new conservation techniques

Captive breeding cannot sustain migratory Asian houbara Chlamydotis macqueenii without hunting controls

To evaluate the potential contribution of captive breeding to the conservation of exploited migratory Asian houbara Chlamydotis macqueenii, we estimated release numbers required to stabilise a population in a hunting concession (14,300 km2), under scenarios of local licensed hunting and flyway-scale protection. We developed a population model, initially 2350 adult females, re-sampling parameters measured through fieldwork and satellite telemetry, over 1000 iterations. With current flyway-scale unregulated harvest, and without any licensed hunting in the concession, populations declined at 9.4% year-1 (95% CI: –18.9 to 0% year-1); in this scenario a precautionary approach (85% probability λ≥ 1.0) to population stabilisation required releasing 3100 captive-bred females year-1 (131% x initial wild numbers). A precautionary approach to sustainable hunting of 100 females year-1 required releasing 3600 females year-1 (153% initial wild numbers); but if interventions reduced flyway-scale hunting/trapping mortality by 60% or 80%, sustaining this quota required releasing 900 or 400 females year-1, 38% and 17% of initial wild numbers, respectively. Parameter uncertainty increased precautionary numbers for release, but even with reduced precaution (50% probability λ≥ 1.0), sustainable hunting of 100 females year-1 required annual releases of 2200 females (94% wild) without other measures, but 300 (13%) or no (0%) females under scenarios of a 60% or 80% reduction in flyway-scale hunting/trapping. Captive breeding cannot alone sustain migrant populations of wild C. macqueenii because it risks replacement and domestication. Trade and exploitation must be restricted to avoid either extinction or domestication. For exploited populations, supplementation by captive breeding should be used with caution

Rainfall validates MODIS-derived NDVI as an index of spatio-temporal variation in green biomass across non-montane semi-arid and arid Central Asia

As satellite-derived normalized difference vegetation index (NDVI) is related to vegetation biomass, it may provide a proxy for habitat quality across extensive species ranges where ground-truth data are scarce. However, NDVI may have limited accuracy in sparsely-vegetated arid and semi-arid environments due to signal contamination by substrate reflectance. To validate NDVI as a vegetation proxy in the low-altitude deserts of Central Asia, we examine its response to precipitation across the migratory corridor of Asian Houbara. NDVI increases with precipitation, both spatially (adj. R2 = 0.58, p < 0.001) and temporally (mean adj. R2 across n=244, 1 degree cells = 0.44; GLMM across cells p < 0.001). More vegetated regions show a stronger temporal response of vegetation biomass for a given precipitation increment (slope of NDVI to precipitation in per cell temporal models increases with inter-annual mean NDVI; adj. R2 = 0.38, p < 0.001), reinforcing the conclusion that NDVI provides a proxy for vegetation abundance. The strong signature of rainfall shows MODIS NDVI offers a potentially powerful proxy for spatial and temporal variation in arid and semi-arid vegetation at a resolution of 1 degree and 1 year over the houbara's breeding and wintering range, and probably also at finer spatial resolutions

Plantation clear-fell patches benefit heathland arthropods

1. Plantation forests constitute a significant amount of the wooded area in many parts of the globe. However, the extent of biological provision conferred by plantation forest depends on regional conservation priorities and biogeographical context. 2. Here we evaluate the arthropod biodiversity in a chronosequence of pine planationplantation (clear-felled, 1, 3, 5, 7, 9, 13, 21-years) in the largest lowland conifer forest in the UK. We compare the assemblage within 37 plantation stands and eight important open habitat remnants in a formerly heathland dominated region. We also assess the configuration and potential isolation of ephemeral open early growth stage habitat across a 60-year plantation rotation. 3. Carabid and spider assemblages changed throughout the sampled chronosequence. In the early growth stages (1-7 years) before canopy closure, arthropod assemblages contained many individuals and species associated with dry-open habitats, greater numbers of rare species than closed canopy plantation, and had similar composition (NMDS) to heathland samples. Early growth stages and heathlands primarily differed in the additional presence of generalist species in the plantation. Species associated with woodland increased in abundance as the plantation aged, but remained far less numerous than dry-open or generalist species. The spatial distribution of young growth stages across the rotation cycle was significantly clustered in the early and late rotation phases. 4. Plantation landscapes often support high species richness but we highlight their value for vulnerable heathland biodiversity early in the rotation cycle. To increase plantation value regional conservation priorities should be supported with appropriate consideration of growth stage configuration across the full rotation