Loss of forest cover and host functional diversity increases prevalence of avian malaria parasites in the Atlantic Forest

Host phylogenetic relatedness and ecological similarity are thought to contribute to parasite community assembly and infection rates. However, recent landscape level anthropogenic changes may disrupt host-parasite systems by impacting functional and phylogenetic diversity of host communities. We examined whether changes in host functional and phylogenetic diversity, forest cover, and minimum temperature influence the prevalence, diversity, and distributions of avian haemosporidian parasites (genera Haemoproteus and Plasmodium) across 18 avian communities in the Atlantic Forest. To explore spatial patterns in avian haemosporidian prevalence and taxonomic and phylogenetic diversity, we surveyed 2241 individuals belonging to 233 avian species across a deforestation gradient. Mean prevalence and parasite diversity varied considerably across avian communities and parasites responded differently to host attributes and anthropogenic changes. Avian malaria prevalence (termed herein as an infection caused by Plasmodium parasites) was higher in deforested sites, and both Plasmodium prevalence and taxonomic diversity were negatively related to host functional diversity. Increased diversity of avian hosts increased local taxonomic diversity of Plasmodium lineages but decreased phylogenetic diversity of this parasite genus. Temperature and host phylogenetic diversity did not influence prevalence and diversity of haemosporidian parasites. Variation in the diversity of avian host traits that promote parasite encounter and vector exposure (host functional diversity) partially explained the variation in avian malaria prevalence and diversity. Recent anthropogenic landscape transformation (reduced proportion of native forest cover) had a major influence on avian malaria occurrence across the Atlantic Forest. This suggests that, for Plasmodium, host phylogenetic diversity was not a biotic filter to parasite transmission as prevalence was largely explained by host ecological attributes and recent anthropogenic factors. Our results demonstrate that, similar to human malaria and other vector-transmitted pathogens, prevalence of avian malaria parasites will likely increase with deforestation.     

Environmental heterogeneity and dispersal limitation explain different aspects of β‐diversity in Neotropical fish assemblages

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Evolution of termite functional diversity: analysis and synthesis of local ecological and regional influences on local species richness

Aim To (1) describe termite functional diversity patterns across five tropical regions using local species richness sampling of standardized areas of habitat; (2) assess the relative importance of environmental factors operating at different spatial and temporal scales in influencing variation in species representation within feeding groups and functional taxonomic groups across the tropics; (3) achieve a synthesis to explain the observed patterns of convergence and divergence in termite functional diversity that draws on termite ecological and biogeographical evidence to‐date, as well as the latest evidence for the evolutionary and distributional history of tropical rain forests. Location Pantropical. Methods A pantropical termite species richness data set was obtained through sampling of eighty‐seven standardized local termite diversity transects from twenty‐nine locations across five tropical regions. Local‐scale, intermediate‐scale and large‐scale environmental data were collected for each transect. Standardized termite assemblage and environmental data were analysed at the levels of whole assemblages and feeding groups (using components of variance analysis) and at the level of functional taxonomic groups (using correspondence analysis and canonical correspondence analysis). Results Overall species richness of local assemblages showed a greater component of variation attributable to local habitat disturbance level than to region. However, an analysis accounting for species richness across termite feeding groups indicated a much larger component of variation attributable to region. Mean local assemblage body size also showed the greater overall significance of region compared with habitat type in influencing variation. Ordination of functional taxonomic group data revealed a primary gradient of variation corresponding to rank order of species richness within sites and to mean local species richness within regions. The latter was in the order: Africa > south America > south‐east Asia > Madagascar > Australia. This primary gradient of species richness decrease can be explained by a decrease in species richness of less dispersive functional taxonomic groups feeding on more humified food substrates such as soil. Hence, the transects from more depauperate sites/regions were dominated by more dispersive functional taxonomic groups feeding on less humified food substrates such as dead wood. Direct gradient analysis indicated that ‘region’ and other large‐scale factors were the most important in explaining patterns of local termite functional diversity followed by intermediate‐scale geographical and site variables and, finally, local‐scale ecological variables. Synthesis and main conclusions Within regions, centres of termite functional diversity lie in lowland equatorial closed canopy tropical forests. Soil feeding termite evolution further down food substrate humification gradients is therefore more likely to have depended on the long‐term presence of this habitat. Known ecological and energetic constraints upon contemporary soil feeders lend support for this hypothesis. We propose further that the anomalous distribution of termite soil feeder species richness is partly explained by their generally very poor dispersal abilities across oceans. Evolution, radiation and dispersal of soil feeder diversity appears to have been largely restricted to what are now the African and south American regions. The inter‐regional differences in contemporary local patterns of termite species richness revealed by the global data set point to the possibility of large differences in consequent ecosystem processes in apparently similar habitats on different continents.     

Functional Diversity as a New Framework for Understanding the Ecology of an Emerging Generalist Pathogen

Emerging infectious disease outbreaks are increasingly suspected to be a consequence of human pressures exerted on natural ecosystems. Previously, host taxonomic communities have been used as indicators of infectious disease emergence, and the loss of their diversity has been implicated as a driver of increased presence. The mechanistic details in how such pathogen–host systems function, however, may not always be explained by taxonomic variation or loss. Here we used machine learning and methods based on Gower’s dissimilarity to quantify metrics of invertebrate functional diversity, in addition to functional groups and their taxonomic diversity at sites endemic and non-endemic for the model generalist pathogen Mycobacterium ulcerans, the causative agent of Buruli ulcer. Changes in these metrics allowed the rapid categorisation of the ecological niche of the mycobacterium’s hosts and the ability to relate specific host traits to its presence in aquatic ecosystems. We found that taxonomic diversity of hosts and overall functional diversity loss and evenness had no bearing on the mycobacterium’s presence, or whether the site was in an endemic area. These findings, however, provide strong evidence that generalist environmentally persistent bacteria such as M. ulcerans can be associated with specific functional traits rather than taxonomic groups of organisms, increasing our understanding of emerging disease ecology and origin.     

河流鱼类分类群和功能群的纵向梯度格局——以新安江流域为例

确定鱼类群落的空间格局是保护和管理河流鱼类多样性的基础。尽管河流鱼类分类群（基于物种组成）的纵向梯度格局已得到大量报道,但其功能群（基于功能特征）的空间格局研究较少。以皖南山区新安江为研究流域,沿其"正源-下游"梯度共设置27个调查样点,分别于2017年5月和10月完成2次调查取样,着重研究了鱼类分类群和功能群结构的纵向梯度格局及其形成机制。共采集鱼类44种,可分为5个运动功能群和4个营养功能群,构成14个"营养-运动"复合功能群。双因素交互相似性分析结果显示,鱼类分类群和功能群均随河流级别显著变化,但两者均无显著的季节变化;根据相似性百分比分析,由1级至3级河流,数量优势物种和功能群的空间变化主要呈嵌套格局,而由3级至5级河流其变化主要呈周转格局。方差分解结果显示,局域栖息地、陆地景观和支流空间位置3类解释变量对分类群和功能群空间变化的解释率分别为33.6%和38.5%,其中,分类群受局域栖息地和支流空间位置变量的显著影响,而功能群受局域栖息地和陆地景观变量的显著影响。研究表明,沿着新安江的"上游-下游"纵向梯度,鱼类分类群和功能群的空间格局基本一致,但两者的形成机制不同：分类群的纵向梯度变化受环境过滤和扩散过程的联合影响,而功能群则主要受环境过滤影响。     

Differences in surface-dwelling beetles of grasslands invaded and non-invaded by goldenrods (Solidago canadensis,S. gigantea) with special reference to Carabidae

We evaluated surface-dwelling Coleoptera with special reference to ground beetles (Coleoptera: Carabidae) using pitfall traps across fourteen stands of grasslands invaded and non-invaded by invasive goldenrods (Solidago canadensis L. and S. gigantea Ait.) over a 3 year period. We analysed differences in assemblages of invaded and non-invaded grasslands and tested responses of surface-dwelling beetles and carabids to invasion of goldenrods. We identified 29 Coleoptera families and 91 Carabidae species. Solidago invaded grasslands showed significantly higher activity-abundance of rove and carrion beetles and supported greater diversity and significantly higher evenness of surface-dwelling Coleoptera and the number of sampled families and individuals was higher too. We found lower taxonomic richness and significantly lower activity-abundance of carabids across goldenrods stands. Several less common Carabidae species and significantly higher representation of stenotopic brachypterous habitat specialists were also observed within invaded stands. We confirmed that differences in plant cover connected with invasion of goldenrods, soil moisture and abandonment of invaded habitats are the driving mechanisms of changes in surface-dwelling Coleoptera and ground beetles assemblages composition across Solidago invaded grasslands. Overall, changes of grassland biotopes connected with invasion of goldenrods significantly alter Coleoptera families and Carabidae assemblages, but not necessarily reduce diversity.     

Influence of land use on the taxonomic and functional diversity of dung beetles (Coleoptera: Scarabaeinae) in the southern Atlantic forest of Argentina

The degradation and replacement of native ecosystems affects both their taxonomic and functional biodiversity. However, native species may find a gradient of habitat suitability in different land uses within a region. The aim of this study was to evaluate the effect of land use on the taxonomic and functional diversity of dung beetle assemblages in the southern Atlantic forest of Argentina. Dung beetles were sampled in both the native forest (control) and different land uses (Pine and Yerba mate plantations and cattle pastures) during the 2014 summer, using pitfall traps baited with human feces and rotten meat. Samplings were taken from 20 different sites, with five replicates of each land use and the native forest (100 pitfall traps in total). A total of 1699 beetles of 27 species were captured. Canthon quinquemaculatus, Canthon conformis and Dichotomius sericeus were the most abundant species. Cattle pastures were the land use most negatively affected in their taxonomic and functional diversity, particularly large paracoprid dung beetles. Pine plantations maintained their taxonomic and functional diversity in relation to the native forest and Yerba mate plantations showed, in general, an intermediate situation. Microclimatic conditions (average temperature and humidity and maximum temperature) were correlated with functional diversity (the proportion of large paracoprid dung beetles decreased with increasing temperature) and are probably good predictors to explain the observed patterns of functional diversity of dung beetles. The development of sustainable production systems that preserve the native biodiversity requires the conservation of key components from the ecological niche of native species, especially microclimatic conditions.     

DER: An algorithm for comparing species diversity between assemblages

There is no single diversity index that adequately summarises species diversity, since this is a multidimensional concept and hence should be quantified using a compound statistical measure. Here, we present the DER algorithm, available as an R package on CRAN and as an RWizard application on http://www.ipez.es/RWizard. This algorithm provides tools for differentiating assemblages on the basis of five compounds of diversity: rarity, heterogeneity, evenness, taxonomic/phylogenetic diversity and functional diversity. For all the samples, the algorithm calculates a total of 39 of the indices most often used. All indices of all samples are transformed to a scale range of between 0 and 1, and the algorithm calculates the polar coordinates of all samples with all possible combinations for all five groups of indices. Thus, for each combination, an index of rarity, heterogeneity (species richness is included in this group), evenness, taxonomic/phylogenetic diversity and functional diversity is used for each group to calculate the polar coordinates of all samples. When the polar coordinates of the samples are obtained for each combination, the convex hull and the mean Euclidean distance between samples are calculated. The algorithm selects the combination of indices with the highest value of the mean between convex hull and mean Euclidean distance between samples; priority is therefore given to maximising dispersion between the samples. The polar coordinates of the selected combination are depicted using a diagram from which it is possible to determine the differences in terms of rarity, heterogeneity, evenness, taxonomic/phylogenetic diversity and functional diversity between assemblages.     

Functional diversity and trait–environment relationships of stream fish assemblages in a large tropical catchment

1. The species composition of stream fish assemblages changes across the longitudinal fluvial gradient of large river basins. These changes may reflect both zonation in species distributions and environmental filtering of fish traits as stream environments change from the uplands to the lowlands of large catchments. Previous research has shown that taxonomic diversity generally increases in larger, lowland streams, and the River Continuum Concept, the River Habitat Template and other frameworks have provided expectations for what functional groups of fishes should predominate in certain stream types. However, studies addressing the functional trait composition of fish assemblages across large regions are lacking, particularly in tropical river basins. 2. We examined functional trait–environment relationships and functional diversity of stream fish assemblages in the Río Grijalva Basin in southern Mexico. Traits linked to feeding, locomotion and life history strategy were measured in fishes from streams throughout the catchment, from highland headwaters to broad, lowland streams. Relationships between functional traits and environmental variables at local and landscape scales were examined using multivariate ordination, and the convex hull volume of trait space occupied by fish assemblages was calculated as a measure of functional diversity. 3. Although there were a few exceptions, functional diversity of assemblages increased with species richness along the gradient from uplands to lowlands within the Grijalva Basin. Traits related to swimming, habitat preference and food resource use were associated with both local (e.g. substratum type, pool availability) and landscape‐scale (e.g. forest cover) environmental variables. 4. Along with taxonomic structure and diversity, the functional composition of fish assemblages changed across the longitudinal fluvial gradient of the basin. Trait–environment relationships documented in this study partially confirmed theoretical expectations and revealed patterns that may help in developing a better understanding of general functional responses of fish assemblages to environmental change.     

Relationships between taxonomic and functional components of diversity: implications for conservation of tropical freshwater fishes

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Why and how might genetic and phylogenetic diversity be reflected in the identification of key biodiversity areas?

‘Key biodiversity areas'' are defined as sites contributing significantly to the global persistence of biodiversity. The identification of these sites builds from existing approaches based on measures of species and ecosystem diversity and process. Here, we therefore build from the work of Sgró et al. (2011 Evol. Appl. 4, 326–337. (doi:10.1111/j.1752-4571.2010.00157.x)) to extend a framework for how components of genetic diversity might be considered in the identification of key biodiversity areas. We make three recommendations to inform the ongoing process of consolidating a key biodiversity areas standard: (i) thresholds for the threatened species criterion currently consider a site''s share of a threatened species'' population; expand these to include the proportion of the species'' genetic diversity unique to a site; (ii) expand criterion for ‘threatened species'' to consider ‘threatened taxa’ and (iii) expand the centre of endemism criterion to identify as key biodiversity areas those sites holding a threshold proportion of the compositional or phylogenetic diversity of species (within a taxonomic group) whose restricted ranges collectively define a centre of endemism. We also recommend consideration of occurrence of EDGE species (i.e. threatened phylogenetic diversity) in key biodiversity areas to prioritize species-specific conservation actions among sites.     

Organization of macroalgal assemblages in the Northeast Pacific: the assumption of homogeneity and the illusion of generality

Evidence for the geographic generality of the causes of intertidal zonation and the indirect effects of a keystone predator, the sea otter, on subtidal kelp assemblages was examined. Most research on intertidal algal assemblages has been done at a few protected sites where zonation is distinct. Surveys of wave-exposed intertidal sites in central and northern California show that assemblage structure is highly variable. This indicates that our present understanding of assemblage organization, including the effects of mussel-algal interactions, may not be widely applicable. Surveys of kelp forest habitat along the entire coast of California suggest that deforestation by sea urchins is uncommon in the absence of sea otters. These examples indicate that the generality of commonly accepted causes of algal assemblage structure in the Northeast Pacific may be an illusion based on assumptions of environmental homogeneity.     

Influence of the colonizing substrate on diatom assemblages and implications for bioassessment: a mesocosm experiment

Although diatoms are important bioindicators of ecological quality, their ecological traits are still not well understood. A major issue is that of substrate preferences, which may result in differences in production, and assemblage structure and composition, and which should therefore be taken into account for ecological quality assessment studies. Thus, in this work, the periphyton grown on sand and ceramic tiles in indoor controlled channels were compared to understand whether substrate differences lead to differences in: periphyton production (chlorophyll-a), chlorophyll-b and c concentrations, diatom assemblages (diversity-Shannon-Wiener, cell density, taxonomic composition, trait proportions), and ecological quality assessments (IPS-‘Indice de Polluosensibilité Spécifique’). A combined inoculum of periphyton from four Portuguese streams was introduced to the running channels (six sand and six tile) and left to colonize for 35 days. Epilithic (tiles) and epipsammic (sand) assemblages were sampled at days 14 and 35. We verified that there were no differences in chlorophyll-a concentration over time and between substrates. On both sampling occasions, the epipsammic assemblages had higher concentration of chlorophyll-c and diatom density but without significant differences over time in each substrate. The taxonomic composition was different between substrates and over time. However, these differences were not reflected in ecological quality assessment. The diversity was also similar between substrates in both sampling occasions, but it was higher at day 14. Mobile and stalked species were more abundant over the entire study and differed significantly between substrates, with the epipsammic assemblages presenting higher abundances of both traits. We concluded that the colonizing substrate influences diatom assemblages but not the ecological quality assessment.     

Spatial Distribution and Coexistence Patterns of Caddisfly Larvae (Trichoptera) in a Hungarian Stream

It is well known that stream macroinvertebrates usually show aggregated spatial distributions caused by extrinsic factors and interactions among species and individuals. In the present study, the spatial distribution of caddisfly assemblages and coexistence patterns of larval caddisfly species (Insecta: Trichoptera) were measured in a Hungarian stream reach at three different spatial scales. Caddisfly assemblages showed aggregated, random and regular distributions as measured by the variance‐mean relationship of species richness as sampling area increased from 0.0225 m² to 0.2025 m². The observed coexistence patterns indicated interactions (lower diversity of unique species combinations than expected by chance) among species for aggregated distributions. These interactions among species proved to be positive associations particularly among species belonging to the same functional feeding group. The positive associations and the aggregated distribution of caddisflies supported the hypothesis that microhabitat patches (patchy microhabitat‐macroinvertebrate model) and/or positive biological interactions among species using the same resource (hypothesis of facilitation) have a deterministic effect on the spatial distribution of caddisfly assemblages. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Environmental Heterogeneity and Microbial Inheritance Influence Sponge-Associated Bacterial Composition of Spongia lamella

Sponges are important components of marine benthic communities. High microbial abundance sponges host a large diversity of associated microbial assemblages. However, the dynamics of such assemblages are still poorly known. In this study, we investigated whether bacterial assemblages present in Spongia lamella remained constant or changed as a function of the environment and life cycle. Sponges were collected in multiple locations and at different times of the year in the western Mediterranean Sea and in nearby Atlantic Ocean to cover heterogeneous environmental variability. Co-occurring adult sponges and offsprings were compared at two of the sites. To explore the composition and abundance of the main bacteria present in the sponge mesohyl, embryos, and larvae, we applied both 16S rRNA gene-denaturing gradient gel electrophoresis (DGGE) and sequencing of excised DGGE bands and quantitative polymerase chain reactions (qPCR). On average, the overall core bacterial assemblage showed over 60 % similarity. The associated bacterial assemblage fingerprints varied both within and between sponge populations, and the abundance of specific bacterial taxa assessed by qPCR significantly differed among sponge populations and between adult sponge and offsprings (higher proportions of Actinobacteria in the latter). Sequences showed between 92 and 100 % identity to sequences previously reported in GenBank, and all were affiliated with uncultured invertebrate bacterial symbionts (mainly sponges). Sequences were mainly related to Chloroflexi and Acidobacteria and a few to Actinobacteria and Bacteroidetes. Additional populations may have been present under detection limits. Overall, these results support that both ecological and biological sponge features may shape the composition of endobiont bacterial communities in S. lamella.     

Impact of Oreochromis niloticus (Linnaeus, 1758) (Pisces: Cichlidae) invasion on taxonomic and functional diversity of native fish species in the upper Kabompo River,northwest of Zambia

Invasive alien species have been revealed to drastically alter the structure of native communities; however, there is scarce information on whether taxonomic and functional spaces occupied by native species are equally filled by exotic species. We investigated the diversity of native species to understand the impact of exotic Oreochromis niloticus in the upper Kabompo River, northwest of Zambia using taxonomic and functional diversity indices. To achieve this, two tests were performed (Test 1, compared natives in invaded and uninvaded sections; Test 2, compared natives in invaded section). A total of 17 species were collected for functional diversity computation, out of which fourteen (14) functional trait measurements linked to feeding, locomotion, and life history strategy were taken. Findings revealed that taxonomic and functional diversity values changed with invasion in both tests. Taxonomic diversity was 15% more in invaded than uninvaded sections in Test 1 and was not consistent across sampling points of invaded section in Test 2. Invaded areas were taxonomically less diverse, but functionally diverse in both tests. The analysis of similarity and nonmetric multidimensional scaling revealed no difference in Bray–Curtis similarity assemblages in both tests. Our findings revealed that exotic species more often occupy unfilled gaps in the communities often occupied by the native species; this is achieved by occupying functional spaces. Overall, changes in taxonomic and functional diversity of native species documented here partially confirmed impacts of O. niloticus invasion. Therefore, we recommend a multifaceted approach to assess cumulative impacts of invasion on native species.     

Riverine networks constrain β‐diversity patterns among fish assemblages in a large Neotropical river

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Diversity,palaeoecology and systematics of a marine fossil assemblage from the Late Triassic Cassian Formation at Settsass Scharte,N Italy

A marine fossil assemblage from the Late Triassic (Early Carnian) Cassian Formation is reported. It was retrieved by bulk sampling, including wet sieving and quantitative picking, and by quantitative surface collection. The collection consists of c. 460 specimens (foraminiferans not included) representing 54 species. In terms of abundance and species richness, it is strongly dominated by molluscs, especially gastropods. 97 % of the individuals are molluscs. The most abundant species are the gastropods Goniospira armata, Schartia carinata and Helenostylina convexa, followed by the scaphopod Plagioglypta undulata and the bivalve Palaeonucula strigilata. Disarticulated echinoderm ossicles (mostly echinoids, crinoids, few holothurians) comprise almost all of the rest of the assemblage. The studied assemblage shows moderate diversity, similar to those of previously reported assemblages or associations from basinal settings. However, it differs considerably in taxonomic composition from previously described associations of the Cassian Formation. The abundance of small gastropods is a result of their primary abundance in these ancient living communities and of the sampling method (sieving at 0.5 mm), because most of the previous associations were obtained by performing surface collections, in which small gastropods are easily overlooked. The fauna is interpreted as an autochthonous soft bottom assemblage dominated by species that lived in low epifaunal to shallow infaunal habitats. Detritivory, deposit feeding and microcarnivory represent the main feeding types. Most of the species were fully motile but slow, and either infaunal (scaphopods, nuculids, the gastropod Domerionina) or epifaunal (most other gastropods, echinoids). The present assemblage underlines the pronounced heterogeneity of the Cassian biota. The low grade of lithification and diagenetic alteration facilitates bulk sampling and the investigation of small species. This minimizes possible sampling and preservation biases, so the studied assemblage reflects the alpha diversity of this ancient living community to an unusually high degree. The following gastropod taxa are new: Helenostylina convexa n. sp., Schartia carinata n. gen. n. sp., Schartiinae n. subfam.; Cassianastraea Bandel non Volz is replaced with Bandelastraea nom. nov.     

鄱阳湖湿地大型底栖无脊椎动物多样性对群落次级生产力及稳定性的影响

理解生物多样性对生态系统功能及稳定性的影响对于制定有效的保护管理策略有重要意义。然而,目前生物多样性与群落生产力、稳定性的关系仍存在争议。在鄱阳湖湿地布设30个采样点,于2019年秋季开展大型底栖无脊椎动物群落野外调查。基于底栖动物群落数据,采用广义加性模型分析物种、谱系、功能多样性对鄱阳湖湿地底栖动物群落次级生产力与稳定性的影响。结果表明:底栖动物群落的次级生产力与反映物种多样性的指数(Simpson多样性指数、Shannon-Wiener多样性指数、Pielou均匀度指数)、分类多样性指数、平均分类差异指数、功能丰富度指数等呈显著的负相关,其中Pielou均匀度指数与次级生产力的相关度最高(r²=0.33)。功能多样性对群落次级生产力的空间分异有最高的解释度(r²=0.75)。P/B值(次级生产力与生物量之比代表群落稳定性)与物种、谱系、功能多样性指数均呈正相关,其中功能丰富度与P/B值的相关度最高(r²=0.22)。反映物种多样性的三个指数总体上对P/B值的空间分异解释度最高(r²=0.37)。谱系多样性与次级生产力、P/B值的相关性相对较弱。生物多样性指数总体分别解释了次级生产力和群落稳定性中81.9%、54.8%的变异。上述研究结果表明,生物多样性与群落生产力、稳定性的关系可能因具体的生物群落而异。研究结果对于鄱阳湖湿地的底栖生物多样性保护有参考价值。     

Large-Scale Spatial Distribution Patterns of Gastropod Assemblages in Rocky Shores

Gastropod assemblages from nearshore rocky habitats were studied over large spatial scales to (1) describe broad-scale patterns in assemblage composition, including patterns by feeding modes, (2) identify latitudinal pattern of biodiversity, i.e., richness and abundance of gastropods and/or regional hotspots, and (3) identify potential environmental and anthropogenic drivers of these assemblages. Gastropods were sampled from 45 sites distributed within 12 Large Marine Ecosystem regions (LME) following the NaGISA (Natural Geography in Shore Areas) standard protocol (www.nagisa.coml.org). A total of 393 gastropod taxa from 87 families were collected. Eight of these families (9.2%) appeared in four or more different LMEs. Among these, the Littorinidae was the most widely distributed (8 LMEs) followed by the Trochidae and the Columbellidae (6 LMEs). In all regions, assemblages were dominated by few species, the most diverse and abundant of which were herbivores. No latitudinal gradients were evident in relation to species richness or densities among sampling sites. Highest diversity was found in the Mediterranean and in the Gulf of Alaska, while highest densities were found at different latitudes and represented by few species within one genus (e.g. Afrolittorina in the Agulhas Current, Littorina in the Scotian Shelf, and Lacuna in the Gulf of Alaska). No significant correlation was found between species composition and environmental variables (r≤0.355, p>0.05). Contributing variables to this low correlation included invasive species, inorganic pollution, SST anomalies, and chlorophyll-a anomalies. Despite data limitations in this study which restrict conclusions in a global context, this work represents the first effort to sample gastropod biodiversity on rocky shores using a standardized protocol across a wide scale. Our results will generate more work to build global databases allowing for large-scale diversity comparisons of rocky intertidal assemblages.