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Summary 1.There is often a perceived conflict between recreational access and wildlife conservation. Although many studies have investigated the potential effects on birds, this is the first study to demonstrate an impact of recreational disturbance on population size. 2. We studied the impact of disturbance on a woodlark Lullula arborea population on 16 heathland sites in southern England. These sites all had historical records of breeding woodlarks and together encompassed a range of visitor-access levels. 3. A logistic regression model of patch use was used to quantify the area of habitat suitable for woodlarks. Woodlarks favoured patches with substantial proportions of bare ground and short vegetation. Across heaths, woodlark density (per hectare of suitable habitat) was lower on sites with higher levels of disturbance. Within heaths with recreational access, the probability of suitable habitat being colonized was lower in those areas with greater disturbance and was reduced to below 50% at around eight disturbance events per hour. There was no relationship between disturbance and daily nest survival rates. Birds on heaths with higher levels of disturbance fledged more chicks (per pair) because of a strong density-dependent increase in reproductive output. 4. A model is presented that predicts the consequences for the woodlark population of a range of access scenarios. The impact on the population depends on both the numbers of people and their spatial distribution. Under current access arrangements, a doubling of visitor numbers has little effect, while the same number of people distributed evenly across all sites leads to a major negative impact on the population. Density-dependent breeding success partially balances the negative effects of disturbance; however, we calculated that there is currently a 17% reduction in productivity compared with that predicted in the absence of disturbance. 5. Synthesis and applications . Many previous studies have stressed the negative effects of recreational disturbance on birds' behaviour, distribution and breeding success. However, from a conservation viewpoint, the impact at the population level is of paramount importance. Modelling the population-scale consequences of alternative access scenarios will help policymakers develop appropriate mitigation measures.

The World Conservation Union (IUCN) has developed guidelines that enable the assessment of extinction risk at a regional scale. We used these guidelines to assess the extinction risk of birds in the United Kingdom for comparison with an existing assessment of conservation status. Sixty-four species were categorized as regionally threatened, of which 12 were critically endangered. The categorizations of the 223 species assessed agreed broadly with those from the existing U.K. system, which considers more than extinction risk, thus giving a more complete assessment of conservation status. There was, however, a tendency for the IUCN process to give higher risk status to edge-of-range species (some of which are relatively recent colonists considered of comparatively low conservation concern) and low status to those that have declined substantially but remain common (such as many farmland birds, the focus of considerable conservation effort in the United Kingdom). The final red list depended heavily on the subjective decisions made during the assessment process. An alternative interpretation of the guidelines could have resulted in as many as 19 or as few as 6 species being listed as critically endangered. We recommend the revision of the IUCN guidelines to reduce this subjectivity, in particular with respect to the effect of extralimital populations on the likelihood of regional extinction, and hence the potential for variation in the manner of application between regional red-list assessors. Preventing extinction does not have to be the principal driving force behind conservation action at a regional scale if the continuance of a species is safeguarded in other regions.Listado Rojo IUCN Regional: el Proceso Aplicado a Aves en el Reino Unido Resumen: La Unión Mundial para la Conservación (IUCN) ha desarrollado directrices que permiten la evaluación del riesgo de extinción a escala regional. Utilizamos estas directrices para evaluar el riesgo de extinción de aves en el Reino Unido para compararlas con una evaluación existente del estatus de conservación. Sesenta y cuatro especies fueron catalogadas como amenazadas regionalmente, de las cuales 12 estaban en peligro crítico. Las categorizaciones de las 223 especies evaluadas en su mayoría coincidieron con las del sistema existente, que considera más que el riesgo de extinción, por lo tanto proporciona una evaluación más completa del estatus de conservación. Sin embargo, en el proceso de la IUCN hubo una tendencia a proporcionar mayor estatus de riesgo a especies en el borde de su distribución (algunas de las cuales son colonizadoras relativamente recientes consideradas comparativamente como de bajo interés de conservación) y menor estatus a aquellas que han declinado sustancialmente pero permanecen comunes (como muchas aves de zonas agrícolas, el foco de atención de muchos esfuerzos de conservación en el Reino Unido). La ‡ 1558Regional IUCN Red Listing Eaton et al. lista roja final dependió en buena medida de las decisiones subjetivas que se tomaron durante el proc...

Whether management for so-called umbrella species actually benefits co-occurring biota has rarely been tested. Here, we studied consequences for multiple invertebrate taxa of two grounddisturbance treatments designed to support an avian umbrella species (Eurasian stone-curlew, Burhinus oedicnemus), and whether analysing ecological requirements across the regional species pool predicted beneficiaries. Responses were assessed for the abundance of five bird species of conservation concern, and the abundance, species richness and composition of carabids, staphylinids, other beetles (non-carabid, non-staphylinid), true bugs and ants, sampling 31258 individuals of 402 species in an extensively-replicated experiment across the UK's largest grassheath. Both treatments provided suitable habitat for the umbrella species, in contrast to controls.Treatment influenced the abundance of only one bird species; but carabid, other beetle and ant richness increased with one or both treatments, while staphylinid richness and abundance increased and true bug richness and abundance decreased with both treatments. Richness of 'priority' (rare, scarce or threatened) invertebrates a priori considered to share ecological requirements with the umbrella species (predicted beneficiaries) increased with both treatments. Resampling and rarefaction showed landscapes diversified by treatment supported a greater cumulative species richness of other beetles, ants and true bugs, and importantly priority invertebrates, than a landscape comprising only untreated controls. Such experiments provide strong evidence to assess co-benefits of umbrella species management, but are costly and time consuming. The systematic examination of the autoecological requirements of co-occurring taxa (the 'Biodiversity Audit Approach') successfully predicted likely beneficiaries. Demonstrating wider biodiversity benefits strengthens the case for avian conservation management.

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