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There is considerable debate over the most appropriate method for surveying dragonflies and damselflies (odonates). Using data from 62 survey locations nested within 26 waterbodies at 15 sites (discrete parcels of common ownership) in West Suffolk, UK, we show that short (20 m line transects or 3 min duration point counts), monthly counts of adults are repeatable. Correlations between predictions from models accounting for variation in ambient conditions and time of day and 52 separate counts used for validation equalled r = 0.87 for total abundance and r = 0.75 for species richness. Correlation coefficients between observed and modelled abundance exceeded 0.5 for eight of fourteen species modelled individually. Ambient temperature was the most important weather variable that influenced survey results, affecting the abundance of nine species, total abundance and species’ richness. Most of the spatial variation in survey results was between waterbodies, rather than between sites or at individual survey locations, suggesting that adult counts may indicate aspects of waterbody quality, although differences in these patterns were observed between dragonflies (Anisoptera) and damselflies (Zygoptera). Encouraging relatively infrequent and rapid counts of flying adults may therefore be used to increase volunteer participation in citizen (community) science odonate monitoring schemes whilst also providing repeatable abundance and species richness data that can contribute to research and monitoring programmes.

Context: Climate change is a severe threat to biodiversity. Areas with a high variety of microclimates may provide opportunities for species to persist in a changing climate.\ud \ud Objectives: Test the extent to which microclimate is an important determinant of the distribution of a widespread upland passerine, the meadow pipit Anthus pratensis, and whether microclimate becomes an increasingly important determinant of distribution towards the warm edge of the species’ range.\ud \ud Methods: We used models of the occurrence of meadow pipits based on data from an extensive survey to identify macroclimate and topographic associations, the latter as proxies of microclimate. We assessed magnitude and direction of the effects of microclimate and whether the magnitude of microclimate effects increases as macroclimate suitability declines. \ud \ud Results: The probability of meadow pipit occurrence is significantly correlated with macroclimate and microclimate. Microclimate accounts for about a third of the variation in occupancy probability and has a stronger effect than macroclimate at all three spatial scales considered. Elevation and topographical wetness index are positively correlated with meadow pipit occurrence, while insolation is negatively correlated. Elevation and macroclimate suitability show a positive interaction, while insolation and macroclimate suitability show a negative interaction.\ud \ud Conclusions: Microclimate substantially influences the distribution of the meadow pipit. For high latitude and upland species such as this, suitable areas on cool slopes could form the focus for conservation protection, as these areas are likely to become increasingly utilised and may remain the only locations occupied in otherwise unsuitable climate.

Climate change is an increasing threat to global biodiversity. Whilst there is growing evidence about the potential effectiveness of some aspects of climate change adaptation, the role for site-based management to increase the resilience of vulnerable populations to climate change has been little studied. Here, we test whether such management may reduce the negative effects of unfavourable weather upon a southern range margin Welsh black grouse Tetrao tetrix population that is vulnerable to climate change. The Welsh black grouse recovery programme funded a range of interventions that contributed to a 39% population increase over 10 years. One likely mechanism linking black grouse populations to climate change is the sensitivity of chicks to high June rainfall. We modelled the relationship between June rainfall and management interventions which aimed to increase breeding success (habitat management and lethal predator control) to test whether management could increase the resilience of black grouse populations to such unfavourable weather. Importantly, we found that the negative effect of June rainfall upon productivity was eliminated at sites where predator control occurred, and that productivity was maximised when predator and habitat management were combined. Active management therefore reduced the negative effects of June rainfall upon this vulnerable southern range margin black grouse population, although further work is required to quantify any limits to the success of such management. Active management should be considered as a tool for climate change adaptation in other vulnerable populations, particularly where there is limited potential for species to undergo climate-driven range changes.

Projections of species’ distributions in future climates can aid adaptive conservation strategies. Although presence-absence or presence-only data have been extensively used for this purpose, modelling changes in spatial patterns of abundance provides a more sensitive tool for estimating species’ vulnerabilities to climate impacts. We used abundance data from citizen science bird surveys in the UK and France to predict spatial patterns of future climatic suitability throughout Great Britain for 124 breeding bird species. We project that climatic suitability of Great Britain will increase for 44% of species and decline for 9% of species by 2080. Of the latter group, most are already red-listed for their severe long-term population declines. If our suitability projections translate into population changes, by 2080, conservation listing status will worsen for 10 species and improve for 28 species. Projected changes in climatic suitability translate into net gains of species abundance in northern and western areas and high turnover in community composition throughout Britain, particularly under medium- and high-emission scenarios. In conclusion, community-wide projections of changes in climatic suitability based on abundance indicate that bird assemblages throughout Great Britain will be impacted by climate change and that species already of concern are likely to be impacted hardest. Of the species projected to benefit, the ability of currently red-listed species to respond positively to climate without other interventions is unclear.

Small wind turbines (SWTs) are an increasingly popular means to generate renewable energy worldwide. Flexibility in size and design allow SWTs to be installed in a much wider range of settings compared to large wind turbines. While large wind turbines can cause substantial mortality of birds and bats, the extent and correlates of such collision mortality at SWTs have not been quantified. Thus, siting decisions for SWTs are currently made with considerable uncertainty of their impact on wildlife. We combined field data and questionnaire surveys of SWT owners to assess the range and correlates of bird and bat mortality at SWT sites (mean hub height 10.2 m [range 4.0-26.4 m], mean rotor diameter 4.0 m [range 0.9-15.0 m], for both free-standing and building mounted turbines). During 171 carcass searches at 21 UK SWT sites we did not find any collision casualties. Thirty-one (14.6 %) of 212 SWT owners reported bird casualties of at least 12 species groups and 3 (1.4 %) reported bat casualties (unidentified species). Based on the questionnaire returns and using a model that accounts for detectability of casualties (through variation in visit frequency, searcher efficiency and average levels of scavenger removal) we estimated that between 0.079 and 0.278 birds, and between 0.008 and 0.169 bats may be killed turbine-1 year-1, equating to 1,567-5,510 birds and 161-3,363 bats year-1 in the UK based on recent estimates of numbers of units installed. Sites with higher levels of bird activity tended to be more likely to report bird casualties. Systematically derived likely ranges of mortality as provided here are urgently needed to inform future SWT planning policy.

Long distance migrants are declining more rapidly than residents, with birds that breed in Europe and winter in tropical Africa providing particularly clear examples. Causal mechanisms may include climate change, but are poorly understood partly because carry-over effects from non-breeding ranges can influence breeding performance. Using long-term data spanning four decades we assess how climatic variation in migrants’ winter, passage and breeding ranges determine timing of breeding and reproductive success. We do so for three Afro-European avian migrants of regional conservation concern (redstart, spotted flycatcher and wood warbler). We find that carry-over effects from passage regions consistently had stronger impacts on breeding phenology than breeding climate. Warm Mediterranean passage conditions promoted earlier breeding in all species, and redstarts also bred earlier following higher Sahel rainfall. Warmer springs on the breeding grounds promoted slightly earlier breeding in redstart and wood warbler, but not spotted flycatcher. Carry-over effects also typically influenced breeding performance to a greater extent than weather on the breeding grounds. Greater rainfall in the Sahel increased redstart brood size, warmer Mediterranean passage conditions increased spotted flycatcher brood size and, to a lesser extent, the number of wood warbler fledglings. In contrast to the concern regarding climate change impacts on migrants’ breeding grounds we found no evidence that warmer temperatures on the breeding grounds were associated with reduced reproductive performance. We thus find that climatic variation on the non-breeding grounds, especially passage regions, typically influenced migrants’ breeding phenology and demography more strongly than equivalent variation on the breeding sites. Such carry-over effects should be considered when assessing the causes of migrants’ marked population declines.

Will networks of protected areas remain effective as the climate changes? Research into the response of bird populations to climate variance and change attempts to shed light on this issue. Results suggest that despite projected declines in many of the species investigated, most sites that are designated as EU Special Protection Areas in the UK can be expected to retain their conservation value and legal status.

There is an urgent need to understand how climate change will impact on demographic parameters of vulnerable species. Migrants are regarded as particularly vulnerable to climate change; phenological mismatch has resulted in the local decline of one passerine, whilst variations in the survival of others have been related to African weather conditions. However, there have been few demographic studies on trans-Saharan non-passerine migrants, despite these showing stronger declines across Europe than passerines. We therefore analyse the effects of climate on the survival and productivity of common sandpipers Actitis hypoleucos, a declining non-passerine long-distant migrant using 28 years' data from the Peak District, England. Adult survival rates were significantly negatively correlated with winter North Atlantic Oscillation (NAO), being lower when winters were warm and wet in western Europe and cool and dry in northwest Africa. Annual variation in the productivity of the population was positively correlated with June temperature, but not with an index of phenological mismatch. The 59% population decline appears largely to have been driven by reductions in adult survival, with local productivity poorly correlated with subsequent population change, suggesting a low degree of natal philopatry. Winter NAO was not significantly correlated with adult survival rates in a second, Scottish Borders population, studied for 12 years. Variation in climatic conditions alone does not therefore appear to be responsible for common sandpiper declines. Unlike some passerine migrants, there was no evidence for climate-driven reductions in productivity, although the apparent importance of immigration in determining local recruitment complicates the assessment of productivity effects. We suggest that further studies to diagnose common sandpiper declines should focus on changes in the condition of migratory stop-over or wintering locations. Where possible, these analyses should be repeated for other declining migrants.

Most studies of climate-driven changes in avian breeding phenology have focused on temperate passerines, yet the consequences of such environmental change may be more deleterious for other avian taxa, such as arctic and sub-arctic waders (Charadrii). We therefore examine large-scale climatic correlates of the breeding phenology of one such species (golden plover Pluvialis apricaria), and the timing of emergence of their adult tipulid prey, to assess the potential for climate change to disrupt breeding performance. Golden plover first-laying dates were negatively correlated with both March and April temperature, the mean laying date of first clutches was additionally negatively correlated with March rainfall. The timing of final laying dates were negatively correlated with April temperature only. The timing of tipulid emergence was negatively correlated with May temperature. In combination with historical climatic data, these models suggest a 9-day advancement of golden plover first-laying dates occurred during the 1990s, although this remains within the range of natural variation for the twentieth century. The magnitudes of predicted changes in mean and final laying dates, and the timing of tipulid emergence, were smaller. Climate predictions for 2070-2099 suggest potential advances in first-laying dates by 25 days, whilst the timings of mean and final laying dates are predicted to change by 18 days and 13 days, and tipulid emergence by 12 days. Given the importance of adult tipulids to young golden plover chicks, these changes may result in a mismatch between the timing of first-laying dates and tipulid emergence, so reducing the success of early breeding attempts. Modelling suggests that these changes could reduce breeding success in a South Pennines population by about 11%.

FOLLOWING the demonstration that diuresis and natriuresis, caused by blood volume expansion with iso-oncotic infusions in dogs, are similar in denervated and innervated kidneys1, it was logical to attempt the direct demonstration by crossed perfusion of a humoral effector mechanism. This undertaking was preceded by the report of Mills et al.2 that diuresis and natriuresis produced by iso-oncotic infusions in dogs could not be prevented by pitressin and mineralocorticoid administration. In the description by de Wardener et al.3 of complicated cross-perfused whole-animal preparations, as well as of isolated kidney perfusions, evidence was advanced for the operation of a natriuretic material following large saline infusions in dogs. Cort and Lichardus4, using carotid occlusion in the cat, have shown that a resulting natriuresis, presumed to be due to blood volume redistribution, could be elicited in a second cat by transferred blood. This experiment offered direct evidence of a natriuretic substance by a bioassay procedure in which the stimulus itself could not have influenced the test animal. A large amount of early work led Homer Smith5 to deduce the existence of a natriuretic system other than the mineralocorticoid mechanism for regulation of sodium metabolism. Recently, evidence has been accumulating, in particular from the work of Levinsky, Hector and Berliner et al.6–8, that expansion of the extracellular fluid volume with saline can decrease renal tubular sodium reabsorption in circumstances where neither change in mineralocorticoid levels nor in glomerular filtration rate can explain the effect.

VAGAL afferents in several vertebrate species have been extensively described1, but we are unaware of any previous recording of afferent activity in the vagus nerve of a primate. The opportunity arose to study these in the monkey Macaca mulatta.