High Conservation Interest Research Articles

Tidal‐flow restoration provides little nesting habitat for a globally vulnerable saltmarsh bird

Tidal marshes are among the most threatened habitats on Earth because of their limited natural extent, a long history of human drainage and modification, and anticipated future sea‐level rise. Tidal marshes also provide services to humans and support species of high conservation interest. Consequently, millions of dollars have been spent on tidal marsh restoration throughout North America. Southern New England has a long history of tidal marsh restorations, often focused on removal of the invasive plantPhragmites australis. Working in 18 Connecticut marshes, we examined the bird community in 21 plots in restoration sites and 19 plots in reference sites. Restoration plots were divided into those in marshes where management involved restoring tidal flow and those where directPhragmitescontrol (e.g. cutting, herbicide) was used. Saltmarsh sparrowsAmmodramus caudacutus, which are considered globally vulnerable to extinction, were less common where tidal flow had been restored than at reference sites and nested in only one of 14 tidal‐flow restoration plots. No abundance differences were found for large wading birds, willetsTringa semipalmata, or seaside sparrowsAmmodramus maritimus. Vegetation at sites where tidal flow had been restored showed characteristics typical of lower‐elevation marsh, which is unsuitable for nesting saltmarsh sparrows. We conclude that, although tidal‐flow restorations in Connecticut controlPhragmitesand restore native saltmarsh vegetation, they produce conditions that are largely unsuitable for one of the highest conservation priority species found in easternU.S.salt marshes.

What is happening after an abiotic disturbance? Response of saproxylic beetles in the Primorsky Region woodlands (Far Eastern Russia)

Abiotic disturbances often totally change the spatial arrangement of the forest environment and potentially reduce the proceeds from the forest. Nature conservationists face considerable pressure to log the wood, or at least to reduce the risk of forthcoming insect outbreaks. The aim of this study was to determine which environmental factors were the most significant for the species composition of subcorticoulous saproxylic beetles in post-disturbance areas. Beetles were studied in Primorsky Region woodlands (Far Eastern Russia) in 2008, in the second year following a heavy snow-break. The composition of saproxylic beetles was influenced significantly, and nearly in the same way, by microhabitat and tree level characteristics. The effect of interaction between microhabitat and tree level was low. Discrimination between coniferous and deciduous trees as the most important factor was followed by the stage of bark peeling, wetness of bast, presence of wood-inhabiting fungi, consistency of bast and sun exposure, all of which were significant predictors. Several taxa showed different demands between adults and larvae (e.g. Cucujus haematodes) or between species within a particular family (e.g. Pyrochroidae). The studied area was definitely not pristine woodland, but the reforestation was non-commercial in nature, with maximum use of natural regeneration and the presence of green trees in disparate life-stages was dominant. The results indicated that natural regeneration with retention of dead wood following a disturbance could be the goal in woodland areas with high conservation interest.

Forest continuity and conservation value in Western Europe

Long forest continuity has often been linked with high conservation value in western European Quercus and Fagus woodlands, but this assumption of long continuity has rarely been tested. Birks discussed the antiquity of bryophyte-rich Quercus woodland in western United Kingdom, presenting evidence that the modern plant communities developed during the late Holocene influenced by human activities. We use pollen data from forest hollows to show that the modern communities within ancient woodlands are all significantly influenced by recent human disturbance. A short period of deforestation in Johnny’s Wood, Cumbria, UK dates from the late 19th century and is not of Viking age as previously thought. The brief opening of the forest is associated with the local loss of Tilia cordata and Taxus baccata, but a rich bryophyte community exists today. Rich lichen floras of high conservation interest growing on Fagus sylvatica in south-western Sweden occur despite a recent history of human disturbance and local immigration of Fagus as recently as the 9th century ad. Wistman’s Wood, Cornwall, UK had a diverse tree flora until the 11th century ad and then experienced heavy browsing and grazing until ad 1850, after which time the present Quercus woodland developed with its associated flora of high conservation value. Most western European forests today have long and diverse histories of anthropogenic disturbance and current conservation values incorporate both natural and cultural features. Pollen studies with high spatial resolution demonstrate that simple temporal concepts like ‘natural baselines’ and the continuity of forest cover underestimate the complexity of the past. Long forest continuity may be of importance for the local survival of higher plants, but for the insects, fungi, lichens and bryophytes that are so valued in contemporary European temperate and boreal forests, habitat diversity maintained by dynamic processes would appear to be of greater significance.

Genetic structure of the rare and endangeredHieracium wiesbaurianumgroup (Asteraceae) in Bavaria

The rare and endangered Hieracium wiesbaurianum species group shows a scattered relictual distribution in Bavaria. Recently, a couple of populations were discovered which clearly differ from all other populations. If these must be considered as taxonomically independent units, they would be of crucial conservation interest, because of the sole responsibility that Bavaria has for these worldwide endemics. We therefore analysed the genetic structure of H. wiesbaurianum in a comparative approach. Our analysis comprised 37 populations of 13 taxa of H. wiesbaurianum, H. bifidum and H. laevigatum, including three potentially new taxa. We applied amplified fragment length polymorphism (AFLP) analysis and observed only limited genetic variation within populations and taxa. Nevertheless, each studied individual exhibited a unique genotype. An analysis of molecular variance revealed high levels of genetic variation between taxa, but populations were genetically less different. The clear genetic differentiation between the studied taxa was supported by neighbor-joining cluster analyses and principal coordinate analyses in which every individual was clearly assigned to its respective taxon. The three potentially new taxa were genetically as well differentiated as the other taxa included in our study. This supports the assumption that they should be treated as taxonomically independent units of high conservation interest. Therefore, the genetic analysis confirmed the morphologically based classification of the studied Hieracium taxa.

Restoration management of fly ash deposits crucially influence their conservation potential for terrestrial arthropods

Fly ash deposits are a relatively common component of many industrial landscapes. Recently, these post-industrial sites were shown to host highly endangered communities of bees & wasps of vanishing continental drift sands. Nevertheless, nothing is known about this conservation potential for other arthropods, nor how it has been influenced by the practice of restoration. We sampled communities of bees wasps, moths, spiders, hoverflies, and ants colonizing several spontaneously developed and technically reclaimed plots in two fly ash deposits in northern Czech Republic, Central Europe. In addition to species richness, we also concentrated on the potential for colonization by species included in national red-lists and/or specialized to the highly threatened environments of continental drift sand dunes. In total, we recorded 585 species of the studied arthropods, including six considered as nationally extinct, 17 critically endangered, and 84 other red-listed species. From those numbers, 34 species were highly specialized for drift sands. bees & wasps and spiders comprised the overwhelming majority of the threatened species, and all the specialists. The overwhelming majority of the most threatened species colonized the non-reclaimed habitats and generally avoided afforested plots. Some of the endangered bees & wasps occurred also in the artificial grasslands, probably feeding on nectar. Summarizing, the studied fly ash deposits harbor arthropod communities of high conservation interest, importance of the spontaneously developed habitats differ among individual arthropod groups. However, this conservation potential is suppressed by artificial afforestation. Following the occurrence patterns of the most threatened species we suggest applying a mosaic-like combination of non-reclaimed habitats with reclaimed grasslands as a potentially effective solution combining both biodiversity conservation and environmental protection. The expected ensuing controversy of this approach should be one of the most essential challenges of current restoration ecology research and practice.

Forgotten grasslands of the South

book reviews ISSN 1948-6596 Forgotten grasslands of the South Forgotten Grasslands of the South: Natural History and Conservation. Reed F. Noss, 2012, Island Press. 320 pp. $70 (Hardback), $35 (Paperback) ISBN: 9781610912259 / 9781597264891; http://islandpress.org This book is a major contribution to the argument that open grasslands and savannas, in climates that can support closed forests, are not only of considerable antiquity but are also home to rich floras and faunas of high conservation interest. Reed Noss focuses on the “forgotten” grasslands of the south-eastern USA. With foresters’ bias to trees, the long-leaf pine ecosystems of this area have generally been classified as ‘forests’. Yet it is the understorey that tells the real story—one of shade-intolerant (mostly C4) grasses and other plants and animals living in open, light-rich envi- ronments. The conundrum is that the climate is warm enough and wet enough to support forests dominated by trees that cast dense shade. The same conundrum faces the tropical ecologist con- fronting the vast areas of savannas in seasonally humid climates that also support closed forests. The classic solution, plugged for well over a cen- tury, is that the grasslands are ‘cultural artefacts’, created by felling and burning of the forests. Over the last couple of decades, this idea has been challenged by multiple lines of evidence pointing to ancient origins of grasslands and even more ancient origins of vegetation fires that help create and maintain them. Noss’s book is the best case study I have read on the mis-reading of grassy vegetation and its catastrophic consequences for conservation of these highly threatened ecosys- tems. Noss’s mission is to promote an apprecia- tion for, and understanding of, these neglected systems. Directed at naturalists, conservation bi- ologists and field biologists, much of the book is written as a personal narrative, including memo- rable outings with knowledgeable naturalists, with many descriptions of species and special sites that clearly delight the author. But Noss also writes for a more general readership with informed discus- sion of general ideas of conservation biology, sa- vanna ecology, fire and large-mammal herbivory, patterns of species richness and endemism, geol- ogy as the foundation for community organisation and more. The net effect is a superb case study, rich in detail but broad in intellectual scope, that places North American grassy ecosystems firmly in the burgeoning world literature on savannas and related grasslands. Relative to the savannas of the southern hemisphere the pine savannas of the south- eastern USA are unusual in generally lacking a dis- tinct dry season (typically > 5 months). Just why a long dry season favours savannas is not well un- derstood but a favoured hypothesis is that it pro- vides more time for fires to burn, helping promote savannas at the expense of fire-intolerant forests. In the grasslands of the south, however, the lack of a distinct dry season is offset by the very high frequency of lightning and thunder storms (with some areas receiving > 100 thunderstorms per year!). Thus even small areas of vegetation have a high probability of being hit by lightning strikes. Not all grasslands depend on fire (or large mam- malian herbivores) for their existence. Noss’s dis- cussion of edaphic savannas is the best I have seen anywhere. The origin of C4 grasses, which dominate the southern grasslands, is now thought to be ~ 30 million years ago. Yet their assembly into a major world biome only occurred some 20 million years later. The author’s description of the diverse soils and geologies where grasses persist in this forested landscape provides a detailed view of the edaphic ghettos in which savanna biotas may have developed, free from lethal shading by forest trees, millions of years before the explosive spread of the savanna biome from the Late Mio- cene. Cultural prejudices against grassy ecosys- tems as natural vegetation types have led to their neglect until recent times. Part of that neglect in- cludes the study of biodiversity. Noss’s analysis of the biotic richness of the southern grasslands was quite stunning to me. The Atlantic and Gulf Coastal Plain Floristic Province, which includes frontiers of biogeography 6.2, 2014 — © 2014 the authors; journal compilation © 2014 The International Biogeography Society

Cheatgrass (Bromus tectorum) Dominates Cheek Pouch Contents of the Great Basin Pocket Mouse (Perognathus Parvus)

Most of the native shrubsteppe habitat in the northern Columbia Basin of eastern Washington has been invaded by cheatgrass (Bromus tectorum) or converted to agricultural lands. Therefore, ecological patterns and dynamics on native shrubsteppe and reestablished grasslands are of high conservation interest. We analyzed the cheek pouch contents of Great Basin pocket mice (Perognathus parvus) from 48 study sites in this region to quantify seed collection by this species and to determine the influence of habitat type on cheek pouch seed contents. In all 3 habitat types-newly established Conservation Reserve Program (CRP) lands, older CRP lands, and shrubsteppe-B. tectorum constituted the majority of seeds collected from the cheek pouches. Mean generic richness of collected seeds was higher in shrubsteppe than in new CRP habitats. On average, females collected a greater number of seed genera than males did, and pocket mice collected more seed genera as the autumn season progressed. Exotic B. tectorum has become the most frequently collected autumn food resource for pocket mice in the northern Columbia Basin.

Temporal Changes in Socio-Ecological Systems and Their Impact on Ecosystem Services at Different Governance Scales: A Case Study of Heathlands

Heathlands are considered biodiversity hotspots of high conservation interest. However, they are at risk of degradation and disappearance in most parts of Europe mainly due to land abandonment, degradation, and conversion to other land uses. Heathlands are semi-natural systems: their maintenance and survival depends on specific practices such as extensive grazing or burning. Traditionally they provide a wide range of goods and services to societies. In this study we used the ecosystem services (ES) framework to analyze the changes in the demand for and delivery of ES for the heathland landscapes of the Cantabrian Mountains (NW Spain), since the 1950s. Particularly, we analyzed how the social changes since the 1950s have determined changes in stakeholders’ demand for provisioning, cultural and regulating services and how these changes have influenced the vegetation dynamics and conservation status of these systems. We identified a general shift from the provisioning of grazing facilities and local products for the local-regional market to the provisioning of conservation services to satisfy national–international demand. For the present situation we found a clear mismatch between the conservation demand, management practices, and land-use forms. This mismatch threatens to lead to further landscape changes and loss of biodiversity. The results of our multi-scale and -services study can help to increase awareness of the value of currently obtainable benefits from heathlands among stakeholders and managers. The ES approach can improve understanding of the functioning of the socio-ecological heathland system, and inform the development of new management strategies for heathland protection.

Transcriptome sequencing and de novo annotation of the critically endangered Adriatic sturgeon

BackgroundSturgeons are a group of Condrostean fish with very high evolutionary, economical and conservation interest. The eggs of these living fossils represent one of the most high prized foods of animal origin. The intense fishing pressure on wild stocks to harvest caviar has caused in the last decades a dramatic decline of their distribution and abundance leading the International Union for Conservation of Nature to list them as the more endangered group of species. As a direct consequence, world-wide efforts have been made to develop sturgeon aquaculture programmes for caviar production. In this context, the characterization of the genes involved in sex determination could provide relevant information for the selective farming of the more profitable females.ResultsThe 454 sequencing of two cDNA libraries from the gonads and brain of one male and one female full-sib A. naccarii, yielded 182,066 and 167,776 reads respectively, which, after strict quality control, were iterative assembled into more than 55,000 high quality ESTs. The average per-base coverage reached by assembling the two libraries was 4X. The multi-step annotation process resulted in 16% successfully annotated sequences with GO terms. We screened the transcriptome for 32 sex-related genes and highlighted 7 genes that are potentially specifically expressed, 5 in male and 2 in females, at the first life stage at which sex is histologically identifiable. In addition we identified 21,791 putative EST-linked SNPs and 5,295 SSRs.ConclusionsThis study represents the first large massive release of sturgeon transcriptome information that we organized into the public database AnaccariiBase, which is freely available at http://compgen.bio.unipd.it/anaccariibase/. This transcriptomic data represents an important source of information for further studies on sturgeon species. The hundreds of putative EST-linked molecular makers discovered in this study will be invaluable for sturgeon reintroduction and breeding programs.

Factors affecting vegetation and soil recovery in the Mediterranean woodland of the Canary Islands (Spain)

We investigated whether human-induced soil degradation may hinder the regeneration of a semiarid Mediterranean-type ecosystem with high biodiversity and conservation interest on the Canary Islands. To further this aim, the replacement of plant species and life-forms and the variation in soil quality were studied during the process of succession in old fields abandoned at different times and in relicts of the original thermophilous woodland by means of multivariate techniques of ordination (RDA, DCA, CCA) and clustering (k-means + IndVal). The studied ecosystem showed a limited capacity for recovery, which appears to be lower than in other similar semiarid Mediterranean ecosystems. Soil parent material exerted a considerable influence on plant reestablishment, and this process was more efficient with pumice-type rocks. Human activities have given rise to a loss of soil organic matter and an enrichment of certain nutrients, which revert to their normal levels once disturbance ceases. However, the erosion resulting from ploughing, farming and subsequent land abandonment has resulted in irreversible degradation of the soil water regime, thus severely limiting the restoration of the original ecosystem. We concluded that aridification due to soil degradation may, in certain cases, prevent the complete regeneration of thermophilous woodlands of the Canary Islands, and it must be taken into account when performing restoration activities. Pumice mulch can be useful for restoration, as it provides a suitable substrate in key stages of the plant recolonisation process.

Integrating climate change into calcareous grassland management

Summary1. Climate change is rarely taken into consideration in conservation management strategies aimed at protecting biodiversity from other threats. We examined the implications of this perspective in European calcareous grasslands, which are among the richest herbaceous systems of the continent and are therefore of high nature conservation interest. These systems are currently undergoing species loss because of the abandonment of agro‐pastoral practices. Classic ecological theory assumes that conservation management activities (such as regular mowing) and drought events should increase diversity through decreased plant competition in abandoned mesic communities. In turn, this could reduce diversity in xeric communities although positive plant interactions (facilitation) might buffer these negative effects and maintain diversity.2. We studied the effects of regular mowing and experimentally induced drought on diversity and biotic interactions between two transplanted species in mesic and xeric calcareous grasslands. The study sites in south‐western France have not been subjected to any management for the last 30 years.3. Drought did not affect mesic systems although mowing increased plant diversity through decreased competition. By contrast, mowing had no significant effect in xeric systems although drought decreased diversity. Interestingly, transplants were subject to neither competition nor facilitation in the xeric systems.4. Synthesis and applications. Regular mowing and drought events impact plant diversity of mesic and xeric calcareous grassland communities in different ways. We recommend regular mowing of mesic grasslands, even in the context of climate change. By contrast, we recommend less‐frequent mowing of xeric grasslands together with specific interventions such as assisted migration for species with poor drought tolerance. Similar studies in other ecosystems on larger spatial and temporal scales should examine the dual effects of management and climate change to identify appropriate management programmes.

Exploring spatial patterns of vulnerability for diverse biodiversity descriptors in regional conservation planning

In this study, we developed a multi-criteria assessment of spatial variability of the vulnerability of three different biodiversity descriptors: sites of high conservation interest by virtue of the presence of rare or remarkable species, extensive areas of high ecological integrity, and landscape diversity in grid cells across an entire region. We assessed vulnerability in relation to (a) direct threats in and around sites to a distance of 2 km associated with intensive agriculture, building and road infrastructure and (b) indirect effects of human population density on a wider scale (50 km). The different combinations of biodiversity and threat indicators allowed us to set differential priorities for biodiversity conservation and assess their spatial variation. For example, with this method we identified sites and grid cells which combined high biodiversity with either high threat values or low threat values for the three different biodiversity indicators. In these two classes the priorities for conservation planning will be different, reduce threat values in the former and restrain any increase in the latter. We also identified low priority sites (low biodiversity with either high or low threats). This procedure thus allows for the integration of a spatial ranking of vulnerability into priority setting for regional conservation planning.

Nesting habitat segregation between closely related terricolous sphecid species (Hymenoptera:Spheciformes): key role of soil physical characteristics

Microhabitat selection based on abiotic factors was examined in five species of digger wasps (Sphex funerarius, Ammophila heydeni, Ammophila pubescens, Ammophila sabulosa, Bembix tarsata), four of which are of high conservation interest. All the study sites were located in areas affected by anthropogenic disturbance (reclaimed brown-coal mining areas, and railway dykes) in Central Europe. The individual species responded differentially to the variability in each of the physical characteristics measured, which resulted in site-specific exclusion of individual sphecid species. The sphecids were found to discriminate between available microhabitats based on ground inclination (slope) and vegetation cover. All but A. heydeni segregated the microhabitats according to the content of gravel and sand particles. S. funerarius and B. tarsata were limited by their preferences of low soil compactness, whereas A. pubescens utilized highly compacted soils, which were predominant in the study area. Soil shear strength (cohesiveness) was driving the level of gregariousness of the sphecids. In B. tarsata, number of cells per burrow was found to be higher in soils with increased penetration resistance. Experimental increase in soil compactness led to the abandonment of nesting microhabitats in the subsequent nesting seasons. Besides the well-known biotic factors, such as specialization at different size or type of prey, variability in abiotic factors between individual microhabitats (e.g. patches of sand) was found to be both necessary and sufficient to allow the parallel presence of viable populations of several sphecid species.

Functional traits and local environment predict vegetation responses to disturbance: a pan‐European multi‐site experiment

Summary 1. Disturbance is one of the most important factors structuring the taxonomic and functional composition of vegetation. Vegetation resistance or resilience to disturbance depends on local environmental conditions, further modifying the pool of species and traits. This paper aims to understand how disturbance and local environment combine to affect the resistance and resilience of vegetation. 2. A functional‐trait approach was used to detect traits related to vegetation resistance and resilience, and trait attributes of individual species responding to disturbance. Trait approaches enable comparison of vegetation responses across biogeographic regions containing different species pools. 3. At 35 European forest and grassland sites, experimental disturbance (human trampling) was applied at five intensities. Indices for resistance and resilience were calculated, based on total vegetation cover, and related to climate and local site factors. Additional indices were calculated for the most common species to demonstrate traits that confer resistance and resilience to disturbance. 4. Vegetation resistance was related to occurrence of species with traits selected by a history of intensive land use (smaller leaf size, rosette plant form) and local environmental conditions. Vegetation resilience, however, was associated with ecosystem properties that facilitate higher growth rates. Resilient vegetation occurred where irradiation was higher (grasslands, open forests) with sufficient water availability (summer precipitation, humidity) and comprised of species with traits related to enhanced growth rates (increased specific leaf area, decreased leaf dry matter content). 5. Synthesis. This pan‐European disturbance experiment demonstrates that different drivers (land use or climate) of vegetation response show different mechanistic responses to physical disturbance. Resistance depends on the functional composition of predominant species in the assemblage, which is strongly affected by land‐use history; resilience is directly connected to growth rates affected by climate. We argue for the inclusion of land‐use history and climate into the planning process for visitor management, especially in areas of high conservation interest.

The sensitivity of gap analysis to conservation targets

A crucial stage in systematic conservation planning is the definition of explicit conservation targets to be achieved by a network of protected areas. A wide variety of targets have been employed, including overall percentage area, uniform representation of biodiversity features, and variable targets according to conservation interest. Despite the diversity of options, most studies adopt a particular set of targets without further explanation, and few have investigated the effect of target selection on their results. Here, using a data set on the distribution of plants and terrestrial vertebrates in southern France, we investigate how variation in targets can affect both stages of a gap analysis: the assessment of the completeness of an existing reserve network, and the prioritization of areas for its expansion. Target selection had a major impact on the gap analysis results, with uniform targets (50% of each species’ range) emphasizing the representation of common species, and contrasting targets (weighted according to species’ conservation interest) concentrating attention on high conservation interest species and the areas where they occur. Systematic conservation planning exercises should thus pay close attention to the definition and justification of the representation targets employed.

A conceptual framework for the protection of vulnerable habitats impacted by fishing activities in the Mediterranean high seas

This work aims to compile knowledge on ecologically rich habitats that deserve special protection in the Mediterranean high seas. Many marine ecosystems are currently threatened by fishing activities, such as bottom trawling, gillnets and demersal and pelagic long-lines. Especially vulnerable are areas described as either sensitive habitats or essential fish habitats. Among these we highlight the associations of sessile organisms, such as cold coral reefs, mostly detected on continental slopes, seamounts and on the walls of submarine canyons, and those areas considered as hot spots of diversity and habitat of vulnerable fauna, like cold seeps, hydrothermal vents and submarine canyons. Essential habitats for pelagic species are defined by oceanographic features like productive areas associated with upwelling, and in the Mediterranean the spawning areas and migratory routes of bluefin tuna, swordfish, and albacore are of high conservation interest. We propose that in a context of difficult fisheries management in Mediterranean international waters, or high seas, these vulnerable habitats should be protected through the establishment of a web of Marine Protected Areas coordinated by all the involved countries and controlled by strict surveillance.

Coral and Reef Fish in the Northern Quirimbas Archipelago, Mozambique – A First Assessment

—In recent years there has been much interest in the conservation and tourism value of the Quirimbas Archipelago, Mozambique. Historically, biological and conservation work has been focused on the more accessible southern part of the Quirimbas. This paper is a contribution to the knowledge on the resources in the north of the Quirimbas following survey work conducted around Vamizi Island in 2001, 2003 and principally in 2006. The results indicate it may be one of few examples in the region that has not yet suffered the same level of anthropogenic or natural disturbances that other areas in the region have suffered. Anthropogenic impacts are low as a result of its remote location that has kept it relatively isolated from markets. Limited evidence of bleaching mortality indicates that the area may have some resilience to bleaching events. Given its condition and strategic location, we suggest the area is of high conservation and research interest, and is an important economic resource that if managed wisely can contribute to sustainable fisheries and development through tourism. Threats include high levels of immigration, improved access to markets and technology, and oil and gas exploitation. The main recommendation emerging from the study is that the area is in need of timely management and formal protection.Keywords: East Africa, Mozambique, coral reef, conservation, community-based, reef surveys

Effects of long‐term grazing management on sand dune vegetation of high conservation interest

AbstractQuestion:Can long‐term grazing management maintain and restore species‐rich sand dune plant communities within a sand dune site of high conservation interest?Location:Newborough Warren, North Wales, UK.Methods:Vegetation changes that occurred between 1987 and 2003, subsequent to grazing by domestic livestock being introduced to the site after decades with little or no stock grazing, were analysed using data collected from permanent monitoring quadrats over a 16‐year period.Results:At the plant community level, grazing brought about a shift from a tall‐grass dominated, species‐poor community to a more species‐rich community in the dry dunes, but did not change community type in dune slacks. However, at the species level, grazing enhanced the abundance of some desired perennial, annual and biennial species, graminoids and bryophytes in both habitat types. The increased frequency of positive indicator species for habitat condition suggests that grazing was beneficial for species of conservation interest. Ellenberg nitrogen (N) values decreased after grazing in dry habitats but showed no long‐term change independent of grazing, suggesting no increase in site fertility over the study period. Surprisingly, light (L) values also decreased in the dry dunes after grazing.Conclusions:Long‐term grazing management can play an important role for the conservation of dune communities and associated species. Because of its positive effects on species diversity, plant communities and habitat condition in sand dunes, livestock grazing is recommended for conservation management.

Relevance of genetics for conservation policies: the case of Minorcan cork oaks.

Marginal populations of widely distributed species can be of high conservation interest when they hold a significant or unique portion of the genetic diversity of the species. However, such genetic information is frequently lacking. Here the relevance of genetic surveys to develop efficient conservation strategies for such populations is illustrated using cork oak (Quercus suber) from Minorca (Balearic Islands, Spain) as a case study. Cork oak is highly endangered on the island, where no more than 67 individuals live in small, isolated stands in siliceous sites. As a consequence, it was recently granted protected status. Two Bayesian clustering approaches were used to analyse the genetic structure of the Minorcan population, on the basis of nuclear microsatellite data. The different groups within the island were also compared with additional island and continental populations surrounding Minorca. Very high genetic diversity was found, with values comparable with those observed in continental parts of the species' range. Furthermore, the Minorcan oak stands were highly differentiated from one another and were genetically related to different continental populations of France and Spain. The high levels of genetic diversity and inter-stands differentiation make Minorcan cork oak eligible for specific conservation efforts. The relationship of Minorcan stands to different continental populations in France and Spain probably reflects multiple colonization events. However, discrepancy between chloroplast DNA- and nuclear DNA-based groups does not support a simple scenario of recent introduction. Gene exchanges between neighbouring cork oak stands and with holm oak have created specific and exceptional genetic combinations. They also constitute a wide range of potential genetic resources for research on adaptation to new environmental conditions. Conservation guidelines that take into account these findings are provided.

Effects of management regime on the abundance and nest survival of shrubland birds in wildlife openings in northern New England, USA

Many shrubland bird species are declining in eastern North America and as a result forest managers have used a variety of techniques to provide breeding habitat for these species. The maintenance of permanent “wildlife openings” using prescribed burns or mechanical treatments is a widely used approach for providing habitat for these species, but there have been no studies of the effects of treatment regime on bird abundance and nest survival in managed wildlife openings. We studied shrubland birds in wildlife openings on the White Mountain National Forest (WMNF) in New Hampshire and Maine, USA, during 2003 and 2004. We analyzed bird abundance and nest survival in relation to treatment type (burned versus mowed), treatment frequency, time since treatment, and patch area. We found that wildlife openings provided habitat for shrubland birds that are not present in mature forest. There was relatively modest support for models of focal bird species abundance as a function of treatment regime variables, despite pronounced effects of treatment on habitat conditions. This probably was attributable to the combined effects of complex site histories and bird site fidelity. Overall nest success (52%) was comparable to other types of early-successional habitats in the region, but there were few supported relationships between nest survival and treatment variables. We conclude that wildlife openings provide quality habitat for shrubland birds of high conservation interest as long as managers ensure treatment intervals are long enough to permit the development of woody vegetation characteristic of the later stages of this sere. Also, wildlife openings should be large enough to accommodate the territory sizes of all target species, which was ≥1.2 ha in this study.