Effects of stream restoration and management on plant communities in lowland streams

1. We evaluated restoration success on macrophyte species diversity and composition in lowland streams using communities in 30 naturally meandering stream reaches in the western part of Jutland, Denmark, as reference target communities. Fuzzy set clustering was used to examine the floristic and environmental similarity among reaches, whereas fuzzy set ordination was used to relate floristic patterns to environmental variables. 2. Two major groups of streams were identified based on their floristic composition. One group consisted of reference and restored reaches and the other of the majority of channelised reaches. We found that management exerted a strong influence on the macrophyte communities and that the identified groups were related to differences in management intensity. 3. Our results also indicate that bank morphology and bed level affected macrophyte communities in the streams, particularly the richness and abundance of terrestrial species. The analyses performed suggest that shallow and wide banks allow for a larger migration of species from the stream banks into the streams, thereby enhancing species diversity within the stream channel. 4. The results of this study suggest that macrophyte communities in channelised lowland streams can recover following restorative interventions given that stream management (i.e. weed cutting and dredging) is minimised and that stream banks are reprofiled to improve the lateral connectivity between the stream and its valley.     

Habitat selection and diet of Western Capercaillie Tetrao urogallus in an atypical biogeographical region

Ecological features and conservation requirements of populations at the latitudinal limits of a species’ geographical range frequently differ from those in other parts of the range. Identifying such differences is key to implementing effective conservation strategies for threatened range‐edge populations especially, in the context of rapid global warming, at the lower‐latitude range edge. We studied habitat selection and diet of the endangered Cantabrian Capercaillie Tetrao urogallus cantabricus in a recently discovered population at the southernmost edge of the sub‐species’ range. This is the only Western Capercaillie population in the Mediterranean biogeographical region. We combined non‐systematic surveys based on questionnaires, reports and field sampling with data from radiotracking to assess habitat selection. Diet was surveyed by micro‐histological methods from droppings collected in the new population, which inhabits Pyrenean Oak Quercus pyrenaica forests and Scots Pine Pinus sylvestris plantations, and in two Cantabrian populations inhabiting Eurosiberian forests. Capercaillie preferred large (> 500 ha) and medium‐sized (100–500 ha) Pyrenean Oak forest fragments and large Scots Pine plantations. Forest fragments smaller than 100 ha and non‐forested habitats were always avoided. Diet differed markedly between Mediterranean and Eurosiberian populations. Bilberry Vaccinium myrtillus is common in the diet of most Capercaillie populations but was scarce in the study area and so was rare in the diet of the new population. Instead, Rockrose Halimium lasianthum was described for the first time as a major food resource for the Capercaillie and was consumed in autumn and winter. Pine needles were also heavily consumed in winter. We document for the first time the strong preference of Capercaillie for Pyrenean Oak forests and a moderately high consumption of the leaves, buds and acorns of this tree species throughout the year. Habitat selection and diet of this Mediterranean population differ from those of the core Cantabrian and other populations. Our results suggest a wider environmental tolerance (phenotypic plasticity) in the species than previously recognized. We advocate specific protection for this unique range‐edge Capercaillie population and its Pyrenean Oak forest habitat.     

On the heritability of blue‐green eggshell coloration

Abstract Avian blue‐green eggshell coloration has been proposed as a female signal of genetic or phenotypic quality to males. However, little is known about the relative importance of additive genetic and environmental effects as sources of eggshell colour variation in natural populations. Using 5 years of data and animal models, we explored these effects in a free‐living population of pied flycatchers. Permanent environmental and year effects were negligible, although year environmental variance (V_Year) was significant for all but one of the traits. However, we found high–moderate narrow‐sense heritabilities for some colour parameters. Within‐clutch colour variability showed the highest coefficient of additive genetic variation (i.e. evolvability). Previous evidence suggests that eggshell colour is sexually selected in this species, males enhancing parental effort in clutches with higher colour variability and peak values. Eggshell colour could be driven by good‐genes selection in pied flycatchers although further genetic studies should confirm this possibility.     

Passive external transport of freshwater invertebrates by elephant and other mud‐wallowing mammals in an African savannah habitat

1. Recent findings hint at the potential importance of mammals affecting the spatial dynamics of aquatic organisms in areas where mammals live in close association with water. Perhaps the most iconic example of such an environment is the African savannah. 2. We investigated dispersal patterns of freshwater organisms among a set of temporary ponds in SE Zimbabwe to test the hypothesis that large mammals, and particularly African elephants (Loxodonta africana), can be important vectors of aquatic organisms. Dispersal kernels were reconstructed by hatching mud collected from ‘rubbing’ trees located at increasing distances from a set of isolated ponds. To assess the relative importance of other mammalian vectors, the vertical distribution of mud on rubbing trees was mapped and related to the body size of candidate vector species. 3. Laboratory hatching of mud samples revealed large numbers of propagules of 22 invertebrate taxa as well as some aquatic macrophytes. Dispersing communities reflected source communities and diverged with increasing distance from the source. Both dispersal rates and richness of transported taxa decreased significantly with dispersal distance. No indications for differences in dispersal capacity among propagule types were detected. Instead, common propagules were more likely to travel greater distances. Most mud was attached to trees at heights >1.5 m, implicating elephants as the dominant vector. Vertical distributions of tree mud, however, also revealed clustering at heights up to 50 cm and 90–120 cm corresponding to the height of warthog, rhinoceros and buffalo, respectively. Finally, variation in the vertical distribution of mud on trees in combination with differences in vector vagility suggests that local differences in vector species composition may affect passive dispersal dynamics of aquatic organisms. 4. Based on vagility and vector load, mud‐wallowing mammals emerge as highly effective vectors that, in some areas, may be more important in transporting aquatic organisms than traditionally recognised vectors such as waterbirds. Since most large‐ and medium‐sized mammals currently have restricted geographic distributions, it is likely that mammal‐mediated dispersal was more important in the past.     

Developmental instability of vascular plants in contrasting microclimates at ‘Evolution Canyon’

Rocellaria dubia bores into subtidal rocks of karsted limestone in the Adriatic Sea and elsewhere. It also bores into the shells of various bivalve species. The mechanism of boring has hitherto been debated, but examination of occupied shells suggest that this is achieved by mechanical (the shell) abrasion and chemical etching using secretions produced from glands in the anterior mantle. Fast‐growing bivalves such as Ostrea edulis and Pinna nobilis carry heavy R. dubia burdens, and encapsulate the borer in secreted calluses. Slow‐growing bivalves such as the burrowing Venus verrucosa and Glycymeris violacescens carry low R. dubia burdens, are less able to encapsulate the borers, and probably incur enhanced mortalities as a result. Individuals of R. dubia removed from their limestone boreholes re‐secreted adventitious tubes around their siphons, probably from glands in the posterior mantle. The lifestyle of R. dubia is now better understood, and its ability to bore bivalve shells in particular suggests how the more advanced tropical gastrochaenids Cucurbitula and Eufistulana have evolved from initial (as juveniles) bivalve shell borers into occupants of adventitious crypts and tubes, respectively. It is further argued that the Gastrochaenidae show convergent similarities with the similar crypt‐ and tube‐building representatives of the Clavagelloidea. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 786–804.     

Trophic level modulates carabid beetle responses to habitat and landscape structure: a pan‐European study

1. Anthropogenic pressures have produced heterogeneous landscapes expected to influence diversity differently across trophic levels and spatial scales. 2. We tested how activity density and species richness of carabid trophic groups responded to local habitat and landscape structure (forest percentage cover and habitat richness) in 48 landscape parcels (1 km²) across eight European countries. 3. Local habitat affected activity density, but not species richness, of both trophic groups. Activity densities were greater in rotational cropping compared with other habitats; phytophage densities were also greater in grassland than forest habitats. 4. Controlling for country and habitat effects, we found general trophic group responses to landscape structure. Activity densities of phytophages were positively correlated, and zoophages uncorrelated, with increasing habitat richness. This differential functional group response to landscape structure was consistent across Europe, indicated by a lack of a country × habitat richness interaction. Species richness was unaffected by landscape structure. 5. Phytophage sensitivity to landscape structure may arise from relative dependency on seed from ruderal plants. This trophic adaptation, rare in Carabidae, leads to lower phytophage numbers, increasing vulnerability to demographic and stochastic processes that the greater abundance, species richness, and broader diet of the zoophage group may insure against.     

WPA guidance on mental health and mental health care in migrants

The purpose of this guidance is to review currently available evidence on mental health problems in migrants and to present advice to clinicians and policy makers on how to provide migrants with appropriate and accessible mental health services. The three phases of the process of migration and the relevant implications for mental health are outlined, as well as the specific problems of groups such as women, children and adolescents, the elderly, refugees and asylum seekers, and lesbian, gay, bisexual and transgender individuals. The concepts of cultural bereavement, cultural identity and cultural congruity are discussed. The epidemiology of mental disorders in migrants is described. A series of recommendations to policy makers, service providers and clinicians aimed to improve mental health care in migrants are provided, covering the special needs of migrants concerning pharmacotherapies and psychotherapies.     

Synchrony in population counts predicts butterfly movement frequencies

1. Measuring functional connectivity, the ability of species to move between resource patches, is essential for conservation in fragmented landscapes. However, current methods are highly time consuming and expensive. 2. Population synchrony‐ the correlation in time series of counts between two long‐term population monitoring sites, has been suggested as a possible proxy measure of functional connectivity. To date, population synchrony has been shown to correlate with proxies for movement frequency such as the coverage of suitable habitat types in intervening landscapes, and also least cost distances around hostile land cover types. 3. This provides tentative evidence that synchrony is directly driven by movements of the focal species, but an alternative explanation is that these land cover types affect the movement of interacting species (e.g. natural enemies of the focal species) which can also drive synchronous population dynamics. Therefore, what is needed is a test directly relating population synchrony to movement frequencies of a focal species. 4. Here we use data from a 21 year mark‐release‐recapture study and show that population synchrony does indeed predict movements of a focal butterfly species Boloria eunomia (Esper). 5. There is growing evidence that population synchrony can be a useful conservation tool to measure functional connectivity.