A meta‐analysis reveals a positive correlation between genetic diversity metrics and environmental status in the long‐lived seagrass Posidonia oceanica

The seagrass Posidonia oceanica is a key engineering species structuring coastal marine systems throughout much of the Mediterranean basin. Its decline is of concern, leading to the search for short‐ and long‐term indicators of seagrass health. Using ArcGIS maps from a recent, high‐resolution (1–4 km) modelling study of 18 disturbance factors affecting coastal marine systems across the Mediterranean (Micheli et al. 2013, http://globalmarine.nceas.ucsb.edu/mediterranean/ ), we tested for correlations with genetic diversity metrics (allelic diversity, genotypic/clonal diversity and heterozygosity) in a meta‐analysis of 56 meadows. Contrary to initial predictions, weak but significantly positive correlations were found for commercial shipping, organic pollution (pesticides) and cumulative impact. This counterintuitive finding suggests greater resistance and resilience of individuals with higher genetic and genotypic diversity under disturbance (at least for a time) and/or increased sexual reproduction under an intermediate disturbance model. We interpret the absence of low and medium levels of genetic variation at impacted locations as probable local extinctions of individuals that already exceeded their resistance capacity. Alternatively, high diversity at high‐impact sites is likely a temporal artefact, reflecting the mismatch with pre‐environmental impact conditions, especially because flowering and sexual recruitment are seldom observed. While genetic diversity metrics are a valuable tool for restoration and mitigation, caution must be exercised in the interpretation of correlative patterns as found in this study, because the exceptional longevity of individuals creates a temporal mismatch that may falsely suggest good meadow health status, while gradual deterioration of allelic diversity might go unnoticed.     

Spatial and temporal variation in artisanal catches of dolphinfish Coryphaena hippurus off north‐eastern Brazil

The sampling of fish from the artisanal fleet operating with surface lines off north‐eastern Brazil was carried out between 1998 and 2000. Generalized linear models (GLMs) were used to standardize mean abundance indices using catch and fishing effort data on dolphinfish Coryphaena hippurus and to identify abundance trends in time and space, using 1215 surface line deployments. A standard relative abundance index (catch per unit effort, CPUE) was estimated for the most frequent vessels used in the sets, employing factors and coefficients generated in the GLMs. According to the models, C. hippurus catches are affected by the operating characteristics and power of different fishing vessels. These differences highlight the need for standardization of catch and effort data for artisanal fisheries. The highest mean abundance values for C. hippurus were off the state of Rio Grande do Norte, with an increasing tendency in areas with greater depths and more distant from the coast, reaching maximal values in areas whose depths range from 200 to 500 m. The highest mean abundance values occurred between April and June. The higher estimated abundance of C. hippurus in this period off the state of Rio Grande do Norte and within the 200–500 m depth range may be related to a migration pattern of food sources, as its main prey, the flying fish Hirundichthys affinis, uses floating algae as refuge and to deposit its pelagic eggs.     

Patterns of spatio‐temporal distribution,abundance, and diversity in a mosquito community from the eastern Smoky Hills of Kansas

Nearly 30% of emerging infectious disease events are caused by vector‐borne pathogens with wildlife origins. Their transmission involves a complex interplay among pathogens, arthropod vectors, the environment and host species, and they pose a risk for public health, livestock and wildlife species. Examining habitat associations of vector species known to transmit infectious diseases, and quantifying spatio‐temporal dynamics of mosquito vector communities is one aspect of the holistic One Health approach that is necessary to develop effective control measures. A survey was conducted from May to August, 2010 of the abundance and diversity of mosquito species occurring in the mixed‐grass prairie habitat of the Smoky Hills of Kansas. This region is an important breeding ground for North America's grassland nesting birds and, as such, it could represent an important habitat for the enzootic amplification cycle of avian malaria and infectious encephalitides, as well as spill‐over events to humans and livestock. A total of 11 species, belonging to the three genera Aedes, Anopheles, and Culex, was collected during this study. Aedes nigromaculis, Ae. sollicitans, Ae. taeniorhynchus, Culex salinarius, and Cx. tarsalis accounted for 98% of the collected species. Multiple linear regression models suggested that mosquito abundances in the grasslands of the central Great Plains were explained by meteorological and environmental variables. Temporal dynamics in mosquito abundances were well supported by models that included maximum and minimum temperature indices (adjusted R²= 0.73). Spatial dynamics of mosquito abundances were best explained by a model containing the following environmental variables (adjusted R²=0.37): ground curvature, topographic wetness index, distance to woodland, and distance to road. The mosquito species we detected are known vectors for infectious encephalitides, including West Nile virus. Understanding the microhabitat characteristics of these mosquito species in a grassland ecosystem will aid in the control and management of these disease vectors.     

Species abundance patterns of coccinellid communities associated with olive,chestnut and almond crops in north‐eastern Portugal

• 1 The patterns of abundance of coccinellid species associated to the main agricultural tree crops of north‐eastern Portugal namely olive, chestnut and almond were studied.
• 2 During three to four crop seasons, eight olive, five chestnut and one almond groves were sampled. In each grove, five samples were collected from 10 randomly selected trees using the beating technique and the coccinellids were counted and identified to species. Principal component analysis was used to establish associations among crop and coccinellid species.
• 3 The mean species richness was higher in chestnut, with 15 ± 3.81 species/grove, followed by olive and almond, with 13 ± 2.76 and 10 ± 2.97 species/grove, respectively. Scymnus mediterraneus was the most abundant species in olive and almond, whereas Scymnus interruptus was dominant in chestnut. Brumus quadripustulatus, Chilocorus bipustulatus, Scymnus subvillosus, S. mediterraneus and Rhyzobius chrysomeloides were associated with olive, whereas S. interruptus, Coccinella septempunctata and Adalia decempunctata were associated with chestnut and Hippodamia variegata, Oenopia conglobata and Adalia bipunctata with almond. Both Stethorus punctillum and Scymnus apetzi species were similarly associated with chestnut and almond.
• 4 The differences in coccinellid communities could have been related to the kind of prey item present in the different trees. This knowledge can be used to develop integrated pest management programmes that encourage greater natural enemy biodiversity in agroecosystems.

     

A socio‐ecological model for predicting impacts of land‐use and climate change on regional plant diversity in the Austrian Alps

Climate and land‐use change jointly affect the future of biodiversity. Yet, biodiversity scenarios have so far concentrated on climatic effects because forecasts of land use are rarely available at appropriate spatial and thematic scales. Agent‐based models (ABMs) represent a potentially powerful but little explored tool for establishing thematically and spatially fine‐grained land‐use scenarios. Here, we use an ABM parameterized for 1,329 agents, mostly farmers, in a Central European model region, and simulate the changes to land‐use patterns resulting from their response to three scenarios of changing socio‐economic conditions and three scenarios of climate change until the mid of the century. Subsequently, we use species distribution models to, first, analyse relationships between the realized niches of 832 plant species and climatic gradients or land‐use types, respectively, and, second, to project consequent changes in potential regional ranges of these species as triggered by changes in both the altered land‐use patterns and the changing climate. We find that both drivers determine the realized niches of the studied plants, with land use having a stronger effect than any single climatic variable in the model. Nevertheless, the plants' future distributions appear much more responsive to climate than to land‐use changes because alternative future socio‐economic backgrounds have only modest impact on land‐use decisions in the model region. However, relative effects of climate and land‐use changes on biodiversity may differ drastically in other regions, especially where landscapes are still dominated by natural or semi‐natural habitat. We conclude that agent‐based modelling of land use is able to provide scenarios at scales relevant to individual species distribution and suggest that coupling ABMs with models of species' range change should be intensified to provide more realistic biodiversity forecasts.     

粤东大规模海水增养殖区柘林湾浮游细菌的时空分布

2001年9月至2004年12月对粤东大规模海水增养区柘林湾表、底层水体中浮游细菌的时空分布进行调查。结果表明,柘林湾浮游细菌总均值为59．4×10^4／dm^3,与国内外富营养化程度较高的内湾海域大致相当。在平面分布上,浮游细菌总体上表现出湾内高于湾外、养殖区高于非养殖区的分布格局,说明大规模增养殖业对浮游细菌的时空分布具有重要的影响,其中网箱养殖的影响尤其显著。湾顶黄冈河口浮游细菌呈现显著的逐年增加趋势,其原因一方面与调查期间降雨减少有关;另一方面可能是受周边陆源污染输入加剧的影响。在周年变化上,浮游细菌表现为典型的单峰型周年变化模式,主要是受水温的调控。年度峰值出现在夏季高温季节（6～8月）,低谷出现在冬季低温季节（12～2月）。浮游细菌与溶氧呈现显著意义的负相关关系,但低溶氧可能是湾内养殖区初级生产力低下所致,而非浮游细菌耗氧所为。相反,溶氧降低可能会促进专性或兼性厌氧细菌的增加,使养殖环境进一步恶化。     

Long‐term shifts in abundance and distribution of a temperate fish fauna: a response to climate change and fishing practices

Aim South‐eastern Australia is a climate change hotspot with well‐documented recent changes in its physical marine environment. The impact on and temporal responses of the biota to change are less well understood, but appear to be due to influences of climate, as well as the non‐climate related past and continuing human impacts. We attempt to resolve the agents of change by examining major temporal and distributional shifts in the fish fauna and making a tentative attribution of causal factors. Location Temperate seas of south‐eastern Australia. Methods Mixed data sources synthesized from published accounts, scientific surveys, spearfishing and angling competitions, commercial catches and underwater photographic records, from the ‘late 1800s’ to the ‘present’, were examined to determine shifts in coastal fish distributions. Results Forty‐five species, representing 27 families (about 30% of the inshore fish families occurring in the region), exhibited major distributional shifts thought to be climate related. These are distributed across the following categories: species previously rare or unlisted (12), with expanded ranges (23) and/or abundance increases (30), expanded populations in south‐eastern Tasmania (16) and extra‐limital vagrants (4). Another 9 species, representing 7 families, experienced longer‐term changes (since the 1800s) probably due to anthropogenic factors, such as habitat alteration and fishing pressure: species now extinct locally (3), recovering (3), threatened (2) or with remnant populations (1). One species is a temporary resident periodically recruited from New Zealand. Of fishes exhibiting an obvious poleward movement, most are reef dwellers from three Australian biogeographic categories: widespread southern, western warm temperate (Flindersian) or eastern warm temperate (Peronian) species. Main conclusions Some of the region's largest predatory reef fishes have become extinct in Tasmanian seas since the ‘late 1800s’, most likely as a result of poor fishing practices. In more recent times, there have been major changes in the distribution patterns of Tasmanian fishes that correspond to dramatic warming observed in the local marine environment.     

A high‐stress shelly fauna associated with sponge mud‐mounds in the Coniacian Arnager Limestone of Bornholm,Denmark

The benthic macrofaunas of the Upper Cretaceous chalk of NW Europe show characteristically high species‐richnesses and commonly high densities. They are predominated by bivalves, brachiopods, polychaetes, echinoids, crinoids, asteroids, sponges and towards the end of the Cretaceous also by bryozoans. The mound‐bedded chalk of the Coniacian Arnager Limestone on the island of Bornholm in the Baltic Sea, Denmark, differs from this general picture. It was deposited on a small fault block adjacent to the main Bornholm block, which was emerged during much of the Mesozoic and thus occupied a much more proximal position than most other Upper Cretaceous chalks in NW Europe. The Arnager Limestone contains a unique, exceptionally rich and well‐preserved fauna of mainly hexactinellid, lyssacinosan sponges. The low mud‐mounds are interpreted as formed by baffling and trapping of fine sediment particles by the dense sponge thickets. In contrast, the associated shelly fauna is unusually sparse, of very low richness and extremely low density, except for inoceramid bivalves. It represents a strongly depauparated version of the shelly faunas of contemporaneous chalks in NW Europe. The rare specimens of non‐inoceramid shelly species are interpreted to represent occasional successful spatfalls of benthic species from the deeper‐water chalk farther offshore in the Baltic area. The sponge mud‐mounds of the Arnager Limestone show remarkable resemblances with modern sponge mounds recently discovered on the continental shelf of western Canada. They form an important link between the well‐known older Mesozoic sponge mud‐mounds or ‘reefs’ and the modern mounds and are among the youngest examples of Mesozoic sponge mounds.     

Heritability,evolvability, phenotypic plasticity and temporal variation in sperm‐competition success of Drosophila melanogaster

Sperm‐competition success (SCS) is seen as centrally important for evolutionary change: superior fathers sire superior sons and thereby inherit the traits that make them superior. Additional hypotheses, that phenotypic plasticity in SCS and sperm ageing explain variation in paternity, are less considered. Even though various alleles have individually been shown to be correlated with variation in SCS, few studies have addressed the heritability, or evolvability, of overall SCS. Those studies that have addressed found low or no heritability and have not examined evolvability. They have further not excluded phenotypic plasticity, and temporal effects on SCS, despite their known dramatic effects on sperm function. In Drosophila melanogaster, we found that both standard components of sperm competition, sperm defence and sperm offence, showed nonsignificant heritability across several offspring cohorts. Instead, our analysis revealed, for the first time, the existence of phenotypic plasticity in SCS across an extreme environment (5% CO₂), and an influence of sperm ageing. Evolvability of SCS was substantial for sperm defence but weak for sperm offence. Our results suggest that the paradigm of explaining evolution by sperm competition is more complex and will benefit from further experimental work on the heritability or evolvability of SCS, measuring phenotypic plasticity, and separating the effects of sperm competition and sperm ageing.     

Revegetation,restoration and reptiles in rural landscapes: Insights from long‐term monitoring programmes in the temperate eucalypt woodlands of south‐eastern Australia

Over the past decade, there has been a concerted effort to better understand the distribution and abundance of reptiles in agricultural landscapes and to specifically evaluate their response to revegetation (tree and shrub plantings) and habitat restoration in the wheat‐sheep belt of south‐eastern Australia. This article reviews the response of reptiles to revegetation and woodland management and provides ten insights and lessons that can be applied to help improve reptile conservation in temperate eucalypt woodlands and fragmented agricultural landscapes in Australia. The review focuses primarily on revegetation programmes conducted by Landcare and Greening Australia, and management interventions funded by Local Land Services in NSW and Catchment Management Authorities in Victoria.     

Implications for conservation biocontrol of spatio‐temporal relationships between carabid beetles and coleopterous pests in winter oilseed rape

1 The spatio‐temporal distributions of predatory carabid beetles (Coleoptera: Carabidae) and their potential prey, the larvae of three coleopterous pests, Meligethes aeneus (Fabricius) and Ceutorhynchus spp. [Ceutorhynchus pallidactylus (Marsham), the cabbage stem weevil, and Ceutorhynchus assimilis (Paykull), the cabbage seed weevil], were studied within a crop of winter oilseed rape. The distributions of Collembola were recorded as potential alternative prey. Insect distributions were analysed and compared using Spatial Analysis by Distance Indices. 2 Mature larvae of the pests dropped from the crop canopy to the soil for pupation in temporal succession from May to early July. Their distributions within the crop were irregular and differed with species. 3 Adults of seven species or genera of carabid were abundant and active within the crop during May and June: Nebria brevicollis (Fabricius), Anchomenus dorsalis (Pontoppidan), Loricera pilicornis (Fabricius), Amara similata (Gyllenhal), Asaphidion spp., Pterostichus madidus (Fabricius) and Pterostichus melanarius (Illiger). 4 During May, N. brevicollis was spatially associated with peak numbers of M. aeneus larvae and with Collembola. Anchomenus dorsalis was spatially associated with Ceutorhynchus spp. larvae during two peaks in the abundance of the latter in early and late June. Nebria brevicollis and A. dorsalis coincided in both time and space with larvae of the three coleopterous pests when they were most vulnerable to predation by epigeal predators and are therefore good candidates for conservation biocontrol. 5 The importance of carabid beeetles in the natural enemy complex in winter oilseed rape and their potential for biocontrol of spring and summer pests are discussed in relation to husbandry practices for the crop and its adjacent areas which could be manipulated to promote carabid survival for integrated pest management.     

Spatial association of Aspidosperma quebracho‐blanco juveniles with shrubs and conspecific adults in the Arid Chaco,Argentina

Abstract The survival of Aspidosperma quebracho‐blanco juveniles in the Arid Chaco is facilitated under the canopy of nurse plants. The possible effects of nurse plants were studied at intra‐ and interspecific levels by analysing the spatial distribution of juveniles and adults of A. quebracho‐blanco, of the main shrubs Larrea divaricata and Mimozyganthus carinatus, and of the group of deciduous and evergreen shrub species, and their pair associations. Data were analysed using the SADIE (Spatial Analysis by Distance Indices) software. A. quebracho‐blanco seedling abundance followed the distribution pattern of the main shade‐providing species: an aggregated spatial distribution pattern in most of the categories studied. The seedling bank of A. quebracho‐blanco also showed an aggregated pattern and was spatially associated with shrubs and adults of its own species. The intensity of the association depended on the functional types: deciduous Fabaceae, deciduous non‐Fabaceae, evergreen and conspecific adults, each of which provides a different canopy structure and therefore different amounts of shade. The spatial association was significant with the evergreen group, and less significant with the deciduous Fabaceae group. There was no positive association with deciduous non‐Fabaceae, or with gaps (open sky). The differences generated by canopy cover may influence the nurse effect, as observed in the intensity of association of A. quebracho‐blanco with shrubs and conspecific adults.     

Within‐lake distribution patterns of fish assemblages: the relative roles of spatial,temporal and random environmental factors in assessing fish assemblages using gillnets in a large and shallow temperate lake

In this study, the relative role of spatio‐temporal factors and associated environmental variables (water transparency and temperature) were quantified in relation to gillnet samples of fishes in a large and shallow lake (Lake Balaton, Hungary). Most of the variance (56·1%) in the relative abundance data (%) was related to the vertical segregation of fishes. This gradient substantially affected the catch per unit effort (CPUE) by number of the dominant species, the surface‐oriented bleak Alburnus alburnus and the benthic common bream Abramis brama. It also influenced total CPUE, mean fish mass and species richness and diversity. At the lake level, horizontal habitat heterogeneity (i.e. littoral v. offshore) accounted for only 8·3% of the total variance in relative abundance data, but was important in structuring the CPUE of the ruffe Gymnocephalus cernua and the pikeperch Sander lucioperca. The longitudinal environmental gradient (i.e. lake basin), year and season of sampling, water transparency and temperature had significant effects on relative abundance only at the habitat level, but were also important components of variability of CPUE in some species at the lake level. As sampling schemes need to consider the main gradients in fish assemblage distributions, the use of surface and pelagic gillnets should be more intensively incorporated in the study and monitoring of fish assemblages in shallow lakes and lake habitats.     

Changes in spatial and temporal distribution and vocal behavior of Blainville's beaked whales (Mesoplodon densirostris) during multiship exercises with mid‐frequency sonar

The number and distribution of vocalizing groups of Blainville's beaked whales (Mesoplodon densirostris) were analyzed before, during, and after multiship mid‐frequency active sonar operations at the US Navy's Atlantic Undersea Test and Evaluation Center (AUTEC) in the Bahamas. Groups of foraging animals were isolated by detecting their echolocation clicks using an array of bottom‐mounted hydrophones. Two data sets were evaluated consisting of 115 and 240 h of acoustic data in May 2007 and 2008, respectively. Vocal activity was observed to decline during active sonar exercises and increase upon cessation of sonar transmissions in both data sets. Vocal activity did not recover to preexposure levels in the postexposure time period in 2007 nor in the initial postexposure period in the 2008 data set. Clicks detected during sonar operations were generally found to be on the periphery of the hydrophone field and vocal durations declined for those groups that remained on the range in that time period. Receive levels were calculated for several vocal groups of whales and indicated that animals continued to forage when exposed to sonar at levels as high as 157 dB re: μPa.     

The vertical distribution of pronophiline butterflies (Nymphalidae, Satyrinae) along an elevational transect in Monte Zerpa (Cordillera de Mérida, Venezuela) with remarks on their diversity and parapatric distribution

Aim The distribution of neotropical butterflies of the tribe Pronophilini (Lepidoptera, Satyridae) was analysed with the aim of determining (i) the elevational ranges of distribution of each species (ii) the elevational gradient in diversity, and (iii) the existence of parapatric distributions of some closely related species pairs. Location The field study was carried out in the middle and upper section of the valley of the Río Albarregas, a tributary of the Río Chama on the southern slopes of the Serranía de la Culata, in the central part of the Cordillera de Mérida, Venezuela. Methods The material was collected along an elevational transect set on a trail leading from Merida to the Páramo de Los Conejos in the area known as Monte Zerpa. It consisted of a series of 32 collection sites set at every 25 m of altitude and covered an elevation from 2250 m to 3025 m. Results The ranges of Lymanopoda obsoleta, L. albocincta, L. zapatoza, Corades chelonis, C. pannonia, C. medeba, Mygona irmina, Pedaliodes epidipnis, P. japhleta, P. montagna and P. panyasis were all restricted to the lower half of the cloud forest zone and L. diezti, C. pax, P. polla, P. ornata and P. ferratilis were all restricted to the upper part. Two species, Erethris porphyria and Steroma bega, crossed the entire elevational range of the cloud forest zone.The biodiversity, as measured by Shannon’s index, attained a maximum at 2700 m, beyond which it gradually decreased. A parapatric distribution was confirmed for three pairs of closely related species: L. obsoleta and L. diezti, C. chelonis and C. pax and P. montagna and P. ferratilis. Main conclusions The peak in diversity at middle elevations seems to result from the overlapping ranges of species distributed over lower and upper parts of the cloud forest. Correlation of species composition at particular transect sites with elevation showed that increase in elevation was associated with an increase in species composition difference. Post‐mating isolation was suggested as a primary factor responsible for maintaining the parapatric distributions of species occupying the upper and lower zones and preventing their respective distributions from expanding.     

Richness,systematics, and distribution of molluscs associated with the macroalga Gigartina skottsbergii in the Strait of Magellan,Chile: A biogeographic affinity study

Knowledge about the marine malacofauna in the Magellan Region has been gained from many scientific expeditions that were carried out during the 19th century. However, despite the information that exists about molluscs in the Magellan Region, there is a lack of studies about assemblages of molluscs co-occurring with macroalgae, especially commercially exploitable algae such as Gigartina skottsbergii, a species that currently represents the largest portion of carrageenans within the Chilean industry. The objective of this study is to inform about the richness, systematics, and distribution of the species of molluscs associated with natural beds in the Strait of Magellan. A total of 120 samples from quadrates of 0.25 m² were obtained by SCUBA diving at two sites within the Strait of Magellan. Sampling occurred seasonally between autumn 2010 and summer 2011: 15 quadrates were collected at each site and season. A total of 852 individuals, corresponding to 42 species of molluscs belonging to Polyplacophora (9 species), Gastropoda (24), and Bivalvia (9), were identified. The species richness recorded represents a value above the average richness of those reported in studies carried out in the last 40 years in sublittoral bottoms of the Strait of Magellan. The biogeographic affinity indicates that the majority of those species (38%) present an endemic Magellanic distribution, while the rest have a wide distribution in the Magellanic-Pacific, Magellanic-Atlantic, and Magellanic-Southern Ocean. The molluscs from the Magellan Region serve as study models for biogeographic relationships that can explain long-reaching patterns and are meaningful in evaluating possible ecosystemic changes generated by natural causes or related to human activities.