Abundance Of Most Species Research Articles

Microbiome Dysbiosis Is Associated with Castration Resistance and Cancer Stemness in Metastatic Prostate Cancer.

Prostate cancer is the second leading cause of death in males in America, with advanced prostate cancers exhibiting a 5-year survival rate of only 32%. Castration resistance often develops during the course of treatment, but its pathogenesis is poorly understood. This study explores the human microbiome for its implications in castration resistance and metastasis in prostate cancer. RNA sequencing data were downloaded for the bone and soft tissue biopsies of patients with metastatic castration-resistant prostate cancer. These included both metastatic and adjacent normal biopsies. These sequences were mapped to bacterial sequences, yielding species-level counts. A vast majority of species were found to be significantly underabundant in the CRPC samples. Of these, numerous were found to correlate with the expression of known markers of castration resistance, including AR, PI3K, and AKT. Castration resistance-associated signaling pathways were also enriched with these species, including PI3K-AKT signaling and endocrine resistance. For their implications in cancer aggression and metastasis, cancer stem cell markers were further explored for a relation to these species. EGFR and SLC3A2 were widely downregulated, with a greater abundance of most species. Our results suggest that the microbiome is heavily associated with castration resistance and stemness in prostate cancer. By considering the microbiome's importance in these factors, we may better understand the highly aggressive and highly invasive nature of castration-resistant prostate cancer, allowing for the needed improvements in the treatment of this disease.

Associations with landscape and local‐scale wetland habitat conditions vary among migratory shorebird species during stopovers

Wetlands provide many ecosystem services and functions, including critical stopover habitat for numerous migratory bird species. Yet, loss and degradation of wetlands due to land use and land cover changes have greatly reduced wetland extent worldwide, leading to declines of many migratory shorebirds globally. In the Western Hemisphere, wetlands of the North American Great Plains provide important stopover habitat for shorebirds; however, much remains to be learned about shorebird habitat use during stopovers in this region, including species‐specific associations with landscape‐scale wetland availability and characteristics of individual wetlands. To improve understanding of shorebird habitat use during migration, we conducted shorebird surveys at > 14 000 wetlands throughout Oklahoma, USA, from 2007 to 2009. For 16 shorebird species, we analyzed associations between observed abundance and wetland variables, including within‐wetland characteristics and availability of wetlands at multiple spatial scales surrounding survey locations. We found that the scale at which observed abundance of shorebirds was associated with wetland extent varied among species; 10 species responded most strongly to wetland extent at the 500 m scale, but 5 species and 1 species responded most strongly at 1000 and 2000 m scales, respectively. Observed abundance for most species was generally associated with higher wetland density at broad scales, presence of extensive shallow water, more usable area, and limited vegetation within wetlands, yet there was considerable interspecific variation in the strength and in some cases direction of effects of these within‐wetland characteristics. This interspecies variability highlights the importance of conserving a variety of wetland types with differing characteristics that support the entire shorebird community during migration. By informing optimal habitat requirements for shorebirds during a critical stage of their annual cycle, knowledge gained about species‐specific habitat needs from studies like ours can assist with development of conservation and management strategies that contribute to halting and reversing global shorebird declines.

Species-specific adaptations, individual condition, and life-history-induced dispersal strategies of fish larvae along a transverse gradient in a large river

Early life-history properties reveal a considerable variation among riverine fish species and may play a major role in the downstream drift of larval fish. This role, however, remains largely unexplored. Assemblages of drifting fish larvae and their condition during the peak seasons were analyzed along a cross-section from littoral to midstream zones in a free-flowing section in the middle Yangtze River. Assemblage structure and larval body injuries revealed pronounced transverse patterns. These patterns were mainly explained by hydraulic gradients. Highest species occurrence was recorded in the littoral zone. Larval abundance of most species and larval body injury rates were higher in littoral and sublittoral zones. Relative inshore and nearshore larval abundance revealed a significant negative relationship with species-specific initial body size, and varied among species. Larval abundance, body injury rate, and feeding intensity were all higher at night. Our findings revealed considerable habitat preferences of drifting larval fish and suggest important adaptations for reducing starvation- and predation risks. These factors should be considered in species conservation and river management.

Integrating assemblage structure and habitat mapping data into the design of a multispecies reef fish survey

AbstractObjectiveSince 2010, three spatially disjunct reef fish video surveys have provided fishery‐independent data critical to the assessment and management of reef fishes in the Gulf of Mexico. Although analytical approaches have recently been developed to integrate data from these surveys into a single measure of relative abundance and size composition, a more parsimonious approach would be to integrate survey efforts under a single Gulf‐wide survey design. Accordingly, we conducted a retrospective analysis of historical video‐ and habitat‐mapping data to develop a novel stratified random sampling design for conducting surveys of natural and artificial reef habitats.MethodsWe conducted a series of classification and regression tree analyses to delineate both spatial and habitat strata, and conducted simulations to assess the performance of an optimized survey design.ResultSpatially, classification and regression tree results identified three depth strata (10–25 m, >25–50 m, >50–180 m) and three regional strata (north‐central Gulf, Big Bend, southwest Florida) in the eastern Gulf. For both natural and artificial reefs, habitat strata were delineated based on a combination of relative relief (low, medium, high) and size of the individual reef feature, although reef scale differed markedly between natural (<100 m2, 100–1000 m2, >1000 m2) and artificial habitats (<25 m2, 25–100 m2, >100 m2). To optimize effort among sampling strata, effort was allocated proportionally based on a combination of habitat availability and managed‐species richness for each stratum. Simulation results indicated that relative median biases were <10% and relative median absolute deviations <30% on estimates of abundance for most species examined on natural reefs under the optimal design, except Greater Amberjack Seriola dumerili. These measures of bias and imprecision were similar or higher for most species simulated using simple random and stratified random survey designs. Estimated relative median bias and relative median absolute deviations were notably higher for artificial reef surveys.ConclusionBased on these results, survey efforts were integrated as the Gulf Fishery Independent Survey of Habitat and Ecosystem Resources (G‐FISHER) in 2020.

Grassland songbird abundance is influenced more strongly by individual types of disturbances than cumulative disturbances associated with natural gas extraction.

Grassland birds have undergone widespread global population declines due to loss and degradation of native grasslands. Activities associated with non-renewable energy derived from oil and natural gas extraction have substantially increased on grasslands. The cumulative disturbance generated by natural gas development creates a network of non-linear (e.g., bare ground and exotic plant species) and linear (e.g., roads, trails, pipelines) features that may degrade habitat quality for grassland species. We quantified grassland songbird abundance in two areas of southwestern Saskatchewan, Canada, to determine whether variation in abundance 1) depended on the type and amount of disturbance at two spatial extents, and 2) was more affected by the cumulative impacts of natural gas development than any single type of disturbance. We found that specific types of disturbances impacted the abundance of most species to varying degrees. The cover of different types of linear disturbance had the strongest effect on the most species. Natural gas disturbance within 450 m of point counts was more influential than disturbance within 200 m for nearly all species in both areas. Only Savannah sparrow (Passerculus sandwichensis) abundance was most strongly influenced by the cumulative amount of disturbance with abundance decreasing with increased disturbance. Overall, we detected few consistent patterns among species, or within species between our two study areas. Our results indicated that the impact of natural gas infrastructure can extend beyond the local influences associated with well sites and that relatively small amounts of disturbance (<2%) may impact grassland songbird abundance. We recommend that researchers use caution when studying well-density effects or combining individual types of disturbance without understanding the separate effects each type of disturbance has on the species or community of interest. Not doing so may lead to investing resources into management practices that do not have the greatest possible benefit for grassland songbirds.

Full-scale activated sludge transplantation reveals a highly resilient community structure

Well-functioning and stable microbial communities are critical for the operation of activated sludge (AS) wastewater treatment plants (WWTPs). Bioaugmentation represents a potentially useful approach to recover deteriorated systems or to support specific AS processes, but its application in full-scale WWTPs is generally problematic. We conducted a massive transplantation (in one day) exchanging AS from a donor to a recipient full-scale WWTP with similar process type (biological removal of nitrogen and phosphorus) and performance, but with differences in microbial community structure. The treatment performance in the recipient plant was not compromised and the effluent quality remained stable. The AS community structure of the recipient plant was initially very similar to the donor AS, but it almost completely restored the pre-transplantation structure approximately 40 days after transplantation, corresponding to 3 times the solid retention time. Most of the unique species of donor AS added to recipient AS disappeared quickly, although some disappeared more slowly the following months, indicating some survival and potentially a time limited function in the recipient plant. Moreover, the addition in higher abundance of most species already present in the recipient AS (e.g., the polyphosphate accumulating organisms) or the reduction of the abundance of unwanted bacteria (e.g., filamentous bacteria) in the recipient plant was not successful. Moreover, we observed similar abundance patterns after transplantation for species belonging to different functional guilds, so we did not observe an increase of the functional redundancy. Investigations of the microbial community structure in influent wastewater revealed that for some species the abundance trends in the recipient plant were closely correlated to their abundance in the influent. We showed that a very resilient microbial community was responsible for the outcome of the transplantation of AS at full-scale WWTP, potentially as a consequence of mass-immigration from influent wastewater. The overall results imply that massive transplantation of AS across different WWTPs is not a promising strategy to permanently solve operational problems. However, by choosing a compatible AS donor, short term mitigation of serious operational problems may be possible.

Climate change without extinction: Tasmania's small-mammal communities persisted through the Last Glacial Maximum–Holocene transition

Global ecosystems underwent major changes through the Quaternary, as climates cycled from cool and dry glacial conditions to relatively warm and humid interglacial conditions. How these changes affected the diversity and composition of small-mammal communities is mostly unknown, especially for the southern-temperate regions of Australia. We used fossil assemblages from owl regurgitates to investigate changes in small mammals from Tasmania's forest environments over the last 20,000 years, encompassing the transition from cold glacial conditions of the Last Glacial′ Maximum (LGM) into the warmer Holocene. During the early part of this period, Tasmania was connected to mainland Australia via a low-elevation land bridge, but was transformed into a large island by rising sea levels during the Late Pleistocene – Holocene transition. Despite these changes, the regional small-mammal fauna appears to have been persistent over this entire period, with no loss of species. However, the relative abundance of most species changed dramatically, apparently in response to habitat changes, which also provoked substantial shifts in community composition and diversity. A strong indicator of the magnitude of change is Mastacomys fuscus, a graminivorus specialist murid, which dominated the assemblage prior to and during the LGM, but declined as temperature and sea level rose during the Late Pleistocene – Holocene. In contrast, the generalist rodent Pseudomys higginsi, along with the small forest-dependent marsupials Cercartetus spp. and Antechinus spp., became more common during the Holocene. The continued survival of these species to the present, despite divergent environmental needs, implies that Tasmania's complex geomorphology provided multiple refugia that conferred resilience in the face of environmental change.

Global observing for phytoplankton? A perspective

Abstract Environmental changes primarily caused by humans are putting our biosphere under growing pressure. The most optimistic predictions indicate that this will continue for decades, potentially much longer. Managing global ecology through these challenges requires knowledge of what species are present and how their populations are changing. Yet for vast areas of the ocean, the abundance of most species is simply unknown and not monitored. The failure to monitor means conclusions about their global ecological status cannot be robust (Bindoff, N.L., Cheung, W.W.L., Kairo, J.G., Arístegui, J., Guinder, V.A., Hallberg, R. et al. (2019) Changing ocean, marine ecosystems, and dependent communities. In Pörtner, H.-O., Roberts, D.C., Masson-Delmotte, V., Zhai, P., Tignor, M., Poloczanska, E., Mintenbeck, K., Alegría, A. et al. (eds), IPCC Special Report on the Ocean and Cryosphere in a Changing Climate. https://www.ipcc.ch/srocc/chapter/chapter-5/). Yet, this ignorance delays and limits any response. These changes are, however, disrupting the commercial and indigenous harvest of essential food resources as well as many other ecosystem services important to human well-being. While the global community has made significant progress on designing a monitoring program, there remain significant gaps, hurdles and other challenges to be overcome. Here, we consider some of these challenges and provide specific recommendations regarding potential next steps toward a minimum global monitoring program for plankton.

Quantitative Assessment of Aphid Parasitoids and Predators in Central Oklahoma Wheat Fields during Five Growing Seasons

Winter wheat (Triticum aestivum L.) is the most widely grown crop in Oklahoma and typically is planted in autumn and harvested in June. Wheat in Oklahoma is often infested by insect pests, the most important of which are the cereal aphids – greenbug, Schizaphis graminum (Rondani), and bird cherry-oat aphid, Rhopalosiphum padi (L.). We sampled a total of 69 wheat fields in central Oklahoma during five wheat-growing seasons. The number of wheat fields sampled ranged from seven in the 2016-2017 growing season to 24 fields in the 2009-2010 growing season. We used a D-vac suction sampler to collect aphids and their natural enemies in wheat fields in early November and again in the middle of March. During the five wheat-growing seasons, adult Lysiphlebus testaceipes (Cresson) and Aphelinus nigritus (Howard) were the most consistent and abundant parasitoids, with L. testaceipes present in each of the five growing seasons. The mean number of adult L. testaceipes per D-vac sample ranged from 1.38 in 2018-2019 to 64.3 adults per sample in the 2008-2009 growing season. Aphelinus nigritus was present in four of the five growing seasons and ranged from 0.86 to 7.82 adults per sample among the four growing seasons. Among arthropod predators, larval coccinellids were found in each growing season and ranged from 2.23 to 15.38 individuals per sample. Spiders were present in the five growing seasons and ranged from 1.63 to 19.0 per sample. Several other predator taxa in samples included Chrysopidae, Hemerobiidae, Nabidae, and Syrphidae. Abundance of most species increased from November to March. Abundance of most natural enemy species (or taxa) was positively correlated to aphid abundance, suggesting natural enemies had an aggregative and/or reproductive numerical response to aphid populations.

Partitioning resources through the seasons: abundance and phenology of carrion beetles (Silphidae) in southeastern Ontario, Canada

The coexistence of ecologically similar species is thought to require resource partitioning to minimize competition. Phenological, seasonal differences in activity may provide an important axis for resource partitioning. Here, we test for evidence of seasonal differences in activity within a diverse guild of carrion beetles (Silphidae) in a habitat preserve on the Frontenac Arch, southeastern Ontario, Canada, using a large-scale survey during their active seasons (April to October). We then used generalized additive models to test for differences in seasonal abundance among eight co-occurring carrion beetle species, including five species of burying beetles (Nicrophorinae: Nicrophorus Fabricius, 1775) and three species from the Silphinae subfamily. Consistent with previous work, all species showed seasonal variation in abundance, with peak abundance of most species occurring between June and August. All but one species (Nicrophorus sayi Laporte, 1840) showed positive relationships between abundance and temperature. We find evidence consistent with seasonal partitioning of resources among Nicrophorus habitat generalists that could potentially reduce competition for limited carrion resources. In contrast, we find little evidence for seasonal differences in abundance among Nicrophorus habitat specialists, which instead may partition resources spatially. Overall, our results provide evidence consistent with an important role for seasonal resource partitioning among carrion beetle species that show higher levels of spatial (habitat) overlap within a temperate beetle guild.

Amphibian occurrence and abundance patterns across a modified floodplain ecosystem

AbstractAmphibian populations have experienced unprecedented decline over the past few decades. River regulation, water diversions and reductions in the frequency of reconnections between rivers and floodplains have contributed to decreased floodplain inundation and overall wetland degradation, contributing to regional declines in amphibians. Hydrological modifications coupled with invasive exotic fish also have had a significant impact on inland floodplain frog communities. Using an eight‐year study of 21 wetlands across a nationally important inland floodplain system, we quantified occurrence and abundance patterns in six frog species (adults and tadpoles) to a range of landscape‐scale and site‐scale hydrological and vegetation‐related variables. Occurrence and abundance models for adult frogs and tadpoles were characterised by different suites of predictor variables and effect directions for each species. The occurrence of some frog species, such as the inland banjo frog (Limnodynastes interioris), was negatively related to distance to the main river and area of inundation, whereas the abundance of most species was positively related to mean daily discharge. Tadpoles of species such as the plains froglet (Crinia parinsignifera) had contrasting relationships to introduced common carp (Cyprinus carpio) and eastern gambusia (Gambusia holbrooki). Our findings suggest factors that lead to a particular species occurring at a wetland may differ from those that make them abundant once conditions necessary for occurrence have been met. Thus, management interventions to improve amphibian diversity across inland floodplain systems will need to consider watering actions that benefit a range of frog species, particularly endangered species, across their developmental stages.

Effects of dispersed broadleaved and aggregated conifer tree retention on ground beetles in conifer plantations

Retention forestry is thought to contribute to the balance between biological conservation and timber production. However, its efficacy has mainly been investigated in natural or naturally regenerated forests, and there have been few studies in plantations and Asia. Conifer plantations are quite common in boreal and temperate regions, and native broadleaved trees in conifer plantations are a key structure for maintaining biodiversity in the plantations. We focused on two retention methods in conifer plantations in northern Japan: dispersed broadleaved retention and aggregated conifer retention. We examined the effects of dispersed broadleaved and aggregated conifer retention on forest ground beetles at both the species and community levels and compared the efficacies of these two retention methods under different retention levels. Our results demonstrated that the abundance of forest species in harvested areas increased with the level of dispersed retained trees. We also found that the abundance of forest species decreased in clear-cut areas of aggregated retention sites, whereas the abundance of most species did not decrease within aggregated retention patches of conifer trees and was similar to that in unharvested plantations. It was inferred from the comparison of efficacy between dispersed broadleaved and aggregated conifer retention that the efficacies of the two retention methods were comparable but that at high retention levels, the efficacy of dispersed broadleaved retention could be higher than that of aggregated retention with respect to the species richness of forest species. Our findings demonstrated that retention forestry mitigated the harvest impacts on forest ground beetles in Asian conifer plantations.

Distribution and Abundance of Cetaceans in Icelandic Waters over 30 Years of Aerial Surveys

Beginning in 1986, 7 aerial surveys covering the coastal waters of Iceland have been conducted up to 2016. In addition, several partial surveys covering portions of the same area and at different times of the year have been flown in the same 30 year time span. We present previously unpublished abundance estimates, corrected to the extent feasible for known biases, for common minke whales (Balaenoptera acutorostrata), humpback whales (Megaptera novaeangliae), white-beaked dolphins (Lagenorhynchus albirostris) and harbour porpoises (Phocoena phocoena) from some or all of the 2007, 2009 and 2016 surveys. The relative abundance of most species was comparatively low in the spring and fall, and peaked June and July when all of the main surveys have been carried out. An analysis of changes in line transect density as an index of relative abundance from all surveys indicates that common minke whale abundance decreased by 75% after 2001 and has remained at a relatively low level since then. Relative abundance of humpback whales and white-beaked dolphins has increased over the period 1986-2016. We place these observed changes in context with oceanographic and ecosystem changes documented over the same period.

Breeding Conditions for Birds in the Nowaday Farmlands of the European Russia: the Impact of Agriculture Intensification and Polarization. Part II. Birds

The considerable polarization of bird habitats has been formed in European Russia – extensive abandoned lands, of low suitability for nesting of typical meadow species, alternate with increasingly intensively cultivated fields. Though the abundance of most species is low in these fields, the polarization has resulted in their increasing exploitation by Eurasian Curlew, Black-tailed Godwit, Common Redshank, Black-winged Pratincole, Demoiselle Crane, Montagu's Harrier, Grey Partridge, Short-eared Owl and Mallard, apart from those more typical for fields: Lapwing, Common Quail, Eurasian Skylark, Calandra Lark and Western Yellow Wagtail. However, nesting of these species on most crop fields often results in low breeding success. The trends most unfavorable for nesting birds in European Russia are conversion of grasslands into arable lands, associated with the switching to indoor keeping of cattle, and increasing no-till farming.

Long-term large-scale decline in relative abundances of butterfly and burnet moth species across south-western Germany

Current studies have shown a severe general decline in insect species diversity, their abundance, and a biomass reduction of flying insects. Most of previous studies have been performed at single sites, or were spatially restricted at the landscape level. In this study, we analyse trends of species richness and shifts in species composition of butterflies and burnet moth species across the federal state of Baden-Württemberg in south-western Germany, covering an area of 35,750 km2. The data set consists of 233,474 records and covers a period from 1750 until today. We grouped species according to their species´ specific functional traits and analyse how species with different habitat requirements and behaviour respond to land-use changes over time. Our data document a significant loss of relative abundance for most species, especially since the 1950s until today. Species demanding specific habitat requirements are more seriously suffering under this trend than generalists. This in particular affects taxa adapted to extensively used xerothermic grasslands, bogs or other habitats maintained by traditional low-productivity agricultural practices of the past. Our data indicate large-scale decline in relative abundance of many butterfly and burnet moth species, which happened in particular during the past few decades.

Effects of life‐history traits on stream fish abundances across spatial scales

AbstractIdentifying cross‐scale patterns of ecological processes is imperative, especially in hierarchically structured riverine ecosystems. The role of abiotic factors in determining cross‐scale spatial structure of stream fish populations and communities is well studied, but less is known about how species traits drive cross‐scale patterns. We investigated the role of species traits for explaining autocorrelation of stream fish abundance at spatial scales ranging from local stream reaches to major basins. We calculated intraclass correlation coefficients (ICCs) representing abundance autocorrelation within species (N = 47) at each of five spatial scales. A hierarchical Bayesian regression then modelled ICCs against spatial scale with the resulting regression coefficients modelled as functions of species traits. Finally, we ordinated the scale‐by‐species ICC matrix to calculate an overall metric describing species whose abundances were autocorrelated along a gradient of large to small scales, and modelled this metric as a function of species traits. Abundances of most species were autocorrelated at smaller spatial scales. Maximum fecundity had a significant positive relationship with abundance patterns across spatial scales. Species habitat affinities and body forms were significantly associated with overall abundance patterns across spatial scales: populations of upland/lotic‐affiliated species adapted to streams with high flow correlated at small (≤10 km2) spatial scales. Lowland/lacustrine species with laterally compressed bodies showed little correlation across scales. The appropriate spatial scale for modelling abundance is determined not only by exogenous (e.g. environmental) factors, but also endogenous factors, like traits. Careful consideration of traits and life history will aid researchers in designing more effective and efficient surveys and analyses.

Multiyear monitoring of bird communities in chlorpyrifos-treated orchards in Spain and the United Kingdom: Spatial and temporal trends in species composition, abundance, and site fidelity.

The relationship between agricultural practices and the welfare of wild birds has gained increased attention over the last decades. To assess the potential effects of chlorpyrifos on the bird community, a multiyear, multisite monitoring program was carried out in treated cider orchards (in the United Kingdom) and treated citrus orchards (in Spain). Constant‐effort mist netting was used over several consecutive years in the United Kingdom (2012–2014) and Spain (2010–2012). The general structure of the bird community and the presence of breeding species were analyzed. Twelve and 11 bird species (out of 81 and 45 trapped) in Spain and the United Kingdom, respectively, exceeded the 2% dominance value. For a selection of 6 species in citrus and 4 in cider orchards, N‐mixture models were fitted to the number of trapped birds. The abundance of most species was strongly and significantly affected by seasonality. No species showed any indication of reduction in population size over the years. The results of this extensive field program support the indications that chlorpyrifos spray applications present a low risk to the bird community over the years. Environ Toxicol Chem 2019;38:616–629. © 2018 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.

Inferring abundance trends of key species from a highly developed small-scale fishery off NE Atlantic

Small-scale fisheries (SSFs) are large contributors to worldwide catches and local economies; however, SSFs have been historically under-attended in national and international policies. This work presents a standardization of catch-per-unit-of-effort data obtained from onboard observers for twenty commercial coastal species caught by the SSFs off the Galician coast from 2000 to 2016 using generalized linear mixed models. Operational, environmental, temporal and spatial data were included in the models as explanatory variables. The relative index of abundance for most species varied from year-to-year over the study period and between geographical areas (ICES 9.a and 8.c). Seasonal patterns, likely related to annual biological cycles, were found. Vessel size showed restricted significant effects in abundance estimates, and soak time of fishing operations revealed nonlinear responses of catch rates. Fishing at night or during daylight hours also have significant differences in catch rates that varied among species pointing to behavioural effects on catchability. Catch rates were often negatively related with depth as expected for species with a coastal distribution. Furthermore, seafloor type indicated species-specific habitat preferences, and sea surface temperature played a limited role in abundance estimations. The most common trend of species’ abundance indices showed opposite patterns among geographical areas, suggesting that local conditions may have a significant influence on fluctuations not only at the species level, but also at the community level. This study revealed a generalized lack of correlation between landings and abundance indices, thus landing data was considered, in general, a poor indicator of population status. The data presented increase the fishery knowledge of one of the most important European SSF fleets that ultimately would allow implementing future assessment strategies. It also underpins the fact that fine scale spatial, and temporal observer data, together with environmental and operational information, are critical to infer suitable and unbiased abundance indices within a complex SSF context.

ALMA Astrochemical Observations of the Infrared-luminous Merger NGC 3256

Abstract In external galaxies, molecular composition may be influenced by extreme environments such as starbursts and galaxy mergers. To study such molecular chemistry, we observed the luminous infrared galaxy and merger NGC 3256 using the Atacama Large Millimeter/submillimeter Array. We covered most of the 3 and 1.3 mm bands for a multispecies, multitransition analysis. We first analyzed intensity ratio maps of selected lines such as HCN/HCO+, which shows no enhancement at an active galactic nucleus. We then compared the chemical compositions within NGC 3256 at the two nuclei, tidal arms, and positions with influence from galactic outflows. We found the largest variation in SiO and CH3OH, species that are likely to be enhanced by shocks. Next, we compared the chemical compositions in the nuclei of NGC 3256, NGC 253, and Arp 220; these galactic nuclei have varying star formation efficiencies. Arp 220 shows higher abundances of SiO and HC3N than NGC 3256 and NGC 253. Abundances of most species do not show a strong correlation with star formation efficiencies, although the CH3CCH abundance seems to have a weak positive correlation with the star formation efficiency. Lastly, the chemistry of spiral arm positions in NGC 3256 is compared with that of W51, a Galactic molecular cloud complex in a spiral arm. We found higher fractional abundances of shock tracers, and possibly also a higher dense gas fraction in NGC 3256 compared with W51.

Biome‐scale signatures of land‐use change on raptor abundance: insights from single‐visit detection‐based models

Summary Declines in raptor populations often result from the transformation of natural habitats to anthropogenic land uses, but the rate of population change can vary greatly among species. Declines associated with land transformation have been linked to loss of foraging habitat, prey resources and nest sites due to expanding cultivation, overgrazing and disturbance of nests and persecution by humans. We combined extensive road‐survey counts of raptors, large‐scale GIS data sets and a single‐visit conditional likelihood N‐mixture model to generate biome‐scale projections of abundance as a function of environmental covariates while correcting for detection error and other forms of zero inflation. This approach was employed to investigate how land‐use transformations in the threatened Cerrado savannas and Pantanal wetlands in Brazil have affected the populations of raptors on a large scale (&gt;300 000 km2). We predicted that predominance of land uses with fewer or less accessible prey and scarcer nesting sites would sustain smaller raptor populations. Twelve species were encountered sufficiently to estimate abundance, while 20 others were encountered too infrequently to permit abundance estimation. Detection of all 12 species was influenced by time of day, with variable species‐specific effects that followed expectations based on foraging and flight behaviour. Abundance of most species was negatively influenced by conversion of natural habitats to pastures, an effect that held even for generalist species considered poor indicators of habitat quality, but was not universally impacted by urbanization and soya beans, sugarcane and Eucalyptus plantations, confirming the expectation that some species may tolerate these habitats. Spatial projections of abundance appeared realistic for most species. Synthesis and applications. Protection of the remaining natural habitats is essential to prevent further decline of raptor populations in the Brazilian Cerrado and Pantanal, and restoration of unproductive pastures into natural habitat could prove an efficient strategy to recover diminished raptor populations. The conditional likelihood single‐visit approach is a valid and useful tool for measuring population size and for making detection‐corrected inferences of abundance over large geographical scales with sensible research budgets. Incorporating the approach into a multispecies framework would allow future studies to make important inferences for entire communities.