Higher Species Abundance Research Articles

Diversity of bats (Mammalia, Chiroptera) in the Parque Estadual de São Camilo, Paraná, Southern Brazil

Diversity of bats (Mammalia, Chiroptera) in the Parque Estadual de São Camilo, Paraná, Southern Brazil

Diversity and spatio-temporal variation of phlebotomine sand flies (Phlebotominae: Diptera: Psychodidae) in three different types of land use and seasons in the state of Veracruz, Mexico

A sand fly fauna inventory was conducted in an ecotourism area of central Veracruz, Mexico. We recorded and analyzed the sand fly diversity at 3 different land use types (well-preserved forest, fruit-tree plantations, and human settlements) with sampling conducted 3 times in 1 year (dry, rainy, and cold seasons). A total of 891 specimens of 6 genera and 14 species was recorded. High diversity was detected in the preserved area due to a high species richness and abundance as compared with the fruit-tree plantations and human settlements, respectively. In relation to the seasons of the year, high diversity was found in the cold season as compared with the rainy and dry seasons. The variation of the Phlebotominae assemblage in space and time in the ecotourism zone is described, serving as a baseline to recommend preventive actions to settlers and travelers. Additionally, we include new species records for the state of Veracruz.

South European mountain butterflies at a high risk from land abandonment and amplified effects of climate change

Abstract Data from existing monitoring schemes point to a global crisis of butterflies across Europe, with habitat loss/degradation, climate change and chemical pollution as the main drivers of decline. The existing butterfly time series from Western Europe come from densely populated, relatively flat areas. However, population trends from less populated areas, such as mountain ranges in the south of Europe, have been less studied, despite these areas harbouring one of the highest butterfly biodiversity of the continent. Here, we analyse trends for butterfly populations in a Southwestern Europe mountain range (Picos de Europa, Northwest Spain), for the last 9 years (2013–2021), across an altitudinal gradient (80–2000 m). We show that this region, protected as National Park more than 100 years ago, is nonetheless under a great threat, with a decline in butterfly abundance of, on average, 5.7% per year (45.7% cumulative decline in the last 9 years). Species at higher elevations are faring worse than those at low elevations and communities at mid‐elevations (below the tree line) are changing towards higher abundance of species with a preference from closed habitats. Combined effects of amplified climate change in mountains and habitat loss, due to abandonment of traditional management, appear to be affecting both individual species and community composition of butterflies in our study area.

The Diversity of Reptile Species in Mangrove Ecotourism of Kampung Rawa Mekar Jaya, Siak Regency

Rawa Mekar Jaya mangrove ecotourism is the last mangrove forest on the east coast of Sumatra Island. This mangrove forest is a home for reptiles. The reptilian fauna of the Mekar Jaya mangrove has the potential to become an ecotourism object. This study aims to determine the diversity, evenness, abundance, and status of reptile species in the Mekar Jaya mangrove ecotourism. Four 3 x 400 m transects were conducted in two habitat types: aquatic (10 m of bank) and terrestrial (30 m of bank). Observations were made in the morning and evening at low tide and repeated five times at three-day intervals. Direct collection of reptile data using a visual survey (VES) and passive sampling (glue trap). The researchers managed to capture 52 individuals, which were reptiles, consisting of 4 species (Draco sumatranus, Hemidactylus platyurus, Mabuya multifasciata, and Varanus savator) found directly in the field. The results of the interviews with the managers indicate that there are 2 species of crocodiles: Crocodylus porosus and Tomistoma schlegelii. Shannon-Wiener diversity index value was medium (H'=1.02). Evenness index was labile (0.57). The highest species abundance was M. multifasciata (0.65), while the lowest abundance was H. platyurus (0.12). All reptile species found were not protected. V. salvator is classified as a low-risk species (LC/Minor Concern) and is listed in Appendix II of CITES. Two crocodile species reported by the community are protected. T. schlegelii is vulnerable and listed in Appendix I of CITES. C. porosus is low-risk and listed in CITES Appendix II.

Diversity of Diurnal Beetles in Banguntapan District Yogyakarta

<span>Beetles are insects that have the highest species diversity and abundance of individuals and have various roles in the ecosystem. Changes in land use will certainly affect the diversity, abundance, and dominance of beetles in an ecosystem. This study aims to determine species diversity, species abundance, and individual dominance of beetles, and to compare beetle diversity on non-built land (rice fields and vacant land) compared to built-up land (4 UAD campus and housing). The method in this study is a survey method. Sampling was carried out in October-December 2021 at each sampling location for the UAD 4 campus area, rice fields, housing, and vacant land in Banguntapan District, DIY using <em>pitfall trap </em>planted in the morning and taken in the afternoon, also direct sampling was carried out using bare hand. The beetles that have been obtained are then taken to the laboratory for the identification process. The highest beetle diversity index value was in the rice fields of Banguntapan District, DIY, which was 2,302, while the lowest beetle diversity index value was on campus 4, which was 0.725. The beetle species with the highest species abundance was <em>Gonocephalum </em>sp., while the beetle with the lowest species abundance was <em>Bradycellus</em> <em>nigrinus, Cassida circumdata, Aspidomorpha sanctaecrusis, Verania lineata, </em>and <em>Onthophagus </em>sp. The dominant beetle was <em>Gonocephalum </em>sp., while the less dominant beetle was <em>B. nigrinus.</em></span>

Molluscan assemblages in shelf and slope sedimentary habitats of the Northern Alboran Sea and their linkage to environmental variables

The composition and structure of molluscan assemblages inhabiting circalittoral and upper and middle slope soft bottoms along the northern Alboran Sea, including the Alboran Ridge, was studied in relation to sediment characteristics and water bottom variables. Samples were collected using a beam-trawl (50 sampling stations) during 2014, 2015 and 2016 MEDITS expeditions. A total of 29464 individuals were collected and 215 taxa of six different classes have been found, with gastropods and bivalves representing the most diverse and abundant ones. It is remarkable the presence of rare and uncommon species such as Parthenina palazzii, Cerithiopsis nofronii and Thyasira obsoleta, as well as a new record for Spanish waters: Xanthodaphne dalmasi and two new records for Andalusian waters: Turbonilla amoena and Emarginula pustula. Multivariate analyses using abundance data of living molluscs indicated the presence of seven assemblages in relation to depth and type of sediment. The assemblages identified on circalittoral soft bottoms displayed high species richness and abundance values, and were related to different sediment types. The assemblages located on the platform of the Alboran Ridge displayed the highest species richness values, with a large amount of exclusive species. Some sediment characteristics such as percentage of mud (>80%) and organic matter content, together with depth, were the most influential variables regarding the spatial distribution of the molluscan assemblages. The geographic position of the Alboran Sea, the peculiar oceanographic and hydrological conditions, the diverse sediment types promoting habitat heterogeneity, and the wide depth range may promote the high molluscan biodiversity reported in the present study. The information provided in this study is of importance for improving the knowledge on the diversity of circalittoral and bathyal soft bottoms of the northern Alboran Sea, and provides a baseline for monitoring programs under the framework of different directives such as the Marine Strategy Framework Directive.

Ecological Survey on Species of Poaceae Family Present in Nnamdi Azikiwe University Campus Awka, Anambra State

An ecological survey was done on the species of poaceae family present in Nnamdi Azikiwe University Awka campus. Data was collected from eight different zones of the campus which was randomly divided for adequate coverage and proper representation. Species dominance, percentage cover of species, abundance and diversity of poaceae species were recorded. The result of the study showed that a total of 24 poaceae species were identified in the study area; Eleusine indica had the highest species abundance across the eight zones, with a total frequency of 36 and a total average cover of 28.59, while Sporobulus pyramidalis is the second most abundant with a frequency of 35 and Pennisetum polystachion is the third most abundant with a frequency of 25. The result went further to show the various distributions of the poaceae species across the different zones. Eleusine indica had a relative abundance of 19.4%, followed by Sporobulus pyramidalis (16%) and Pennisetum polystachion (13.5%). More so, Andropogon gayanus had a relative abundance of (8.1%) while Andropogon tectorum, Brachiaria falcifera, Dactyloctenium aegyptium and Digistaria horizontalis as well as Eragrostis tenella, Eragrostis tremela, Panicum maximum and Pennisetum violaccum all had the lowest relative abundance of 0.5 % each. The result of Shannon Wiener index for species of poaceae family in the study area was 2.59 and this showed that there is high diversity of species of poaceae family in the study area which invariably indicates a great potential for utilization in conservation and ecological purposes.

Abundance of Non-Native Birds in the City: Spatial Variation and Relationship with Socioeconomics in a South American City.

Cities commonly support a high abundance of non-native species that can affect both wildlife and human health; however, their distribution across the urban environment and their relationship with socioeconomics are not well documented. Here, we map the abundance of three non-native birds in a Latin American city-domestic pigeon (Columba livia f. domestica), house sparrow (Passer domesticus), and monk parakeet (Myiopsitta monachus)-and investigate the effect of socioeconomics on their abundance. We found that C. livia f. domestica exhibited a random distribution of abundance across the city but reached its greatest abundance in low-income areas. P. domesticus exhibited an aggregated distribution of abundance, being most abundant in the southern and western areas of the city and in low-income areas. M. monachus exhibited an aggregated distribution of abundance, being most abundant in the northeastern part of the city and reaching its greatest abundance in high-income areas. Low-income areas likely provide high abundance of food, shelter, and nesting sites for both C. livia f. domestica and P. domesticus, whereas high income areas have greater tree cover and larger trees in which M. monachus can build communal nests. Our study finds that the abundance of non-native birds varies across the city and between socioeconomic groups; therefore, targeted management is needed in different city zones to limit negative effects on native species and prevent zoonotic diseases.

Commercial banana and macadamia plantations in a savanna matrix support high levels of arthropod diversity

Expansion and intensification of agroecosystems is one of the major causes of habitat loss in the savanna biome in South Africa. As such, this study sought to determine the influence of commercial subtropical fruit plantations (banana and macadamia) on species richness, abundance, and composition of surface-active arthropods compared to the savanna biome. Given that pesticides and herbicides are applied from spring to early autumn in banana and macadamia plantations, we sampled in winter to reduce the potential impact of pesticides and herbicides. Surface-active arthropods were sampled using pitfall traps. Habitat type did not affect species richness and abundance of ants and spiders, as well as species richness of beetles. However, significantly greater abundance of beetles was recorded in the macadamia plantation compared to the banana and savanna. This could have been due to greater abundance of herbivorous beetles and other insects, which would have increased the diversity of predatory beetles. Furthermore, unlike the banana plantation, the macadamia plantation was characterised by a deep leaf litter layer and the presence of weeds and grasses, which probably increased abundance of beetles. Species composition indicated that the studied arthropod taxa associate with specific habitats, as demonstrated by the three habitats supporting different species composition. Despite savanna habitat not supporting high species richness or abundance of surface-active arthropods, we recorded the highest number of unique species of ants and spiders in the savanna rather than in the plantations. These results highlight the importance of natural landscapes in conservation of surface-active arthropods.

Population response of intestinal microbiota to acute Vibrio alginolyticus infection in half-smooth tongue sole (Cynoglossus semilaevis).

Vibriosis causes enormous economic losses of marine fish. The present study investigated the intestinal microbial response to acute infection of half-smooth tongue sole with different-dose Vibrio alginolyticus within 72 h by metagenomic sequencing. The inoculation amount of V. alginolyticus for the control, low-dose, moderate-dose, and high-dose groups were 0, 8.5 × 101, 8.5 × 104, and 8.5 × 107 cells/g respectively, the infected fish were farmed in an automatic seawater circulation system under a relatively stable temperature, dissolved oxygen and photoperiod, and 3 ~ 6 intestinal samples per group with high-quality DNA assay were used for metagenomics analysis. The acute infections with V. alginolyticus at high, medium, and low doses caused the change of different-type leukocytes at 24 h, whereas the joint action of monocytes and neutrophils to cope with the pathogen infection only occurred in the high-dose group at 72 h. The metagenomic results suggest that a high-dose V. alginolyticus infection can significantly alter the intestinal microbiota, decrease the microbial α-diversity, and increase the bacteria from Vibrio and Shewanella, including various potential pathogens at 24 h. High-abundance species of potential pathogens such as V. harveyii, V. parahaemolyticus, V. cholerae, V. vulnificus, and V. scophthalmi exhibited significant positive correlations with V. alginolyticus. The function analysis revealed that the high-dose inflection group could increase the genes closely related to pathogen infection, involved in cell motility, cell wall/ membrane/envelope biogenesis, material transport and metabolism, and the pathways of quorum sensing, biofilm formation, flagellar assembly, bacterial chemotaxis, virulence factors and antibiotic resistances mainly from Vibrios within 72 h. It indicates that the half-smooth tongue sole is highly likely to be a secondary infection with intestinal potential pathogens, especially species from Vibrio and that the disease could become even more complicated because of the accumulation and transfer of antibiotic-resistance genes in intestinal bacteria during the process of V. alginolyticus intensified infection.

Dietary overlap and selectivity among mountain steppe river fish in the United States and Mongolia.

Lotic systems in mountain regions have historically provided secure habitat for native fish populations because of their relative isolation from human settlement and lack of upstream disturbances. However, rivers of mountain ecoregions are currently experiencing heightened levels of disturbance due to the introduction of nonnative species impacting endemic fishes in these areas. We compared the fish assemblages and diets of mountain steppe fishes of the stocked rivers in Wyoming with rivers in northern Mongolia where stocking is absent. Using gut content analysis, we quantified the selectivity and diets of fishes collected in these systems. Nonnative species had more generalist diets with lower levels of selectivity than most native species and native species had high levels of dietary specificity and selectivity. High abundances of nonnative species and high levels of dietary overlaps in our Wyoming sites is a cause of concern for native Cutthroat Trout and overall system stability. In contrast, fish assemblages characterizing Mongolia mountain steppe rivers were composed of only native species with diverse diets and higher selectivity values, suggesting low probability for interspecific competition.

Metabarcoding analysis identifies high diversity of harmful algal bloom species in the coastal waters of the Beibu Gulf.

Harmful algal blooms (HABs) have occurred more frequently in recent years. In this study, to investigate their potential impact in the Beibu Gulf, short-read and long-read metabarcoding analyses were combined for annual marine phytoplankton community and HAB species identification. Short-read metabarcoding showed a high level of phytoplankton biodiversity in this area, with Dinophyceae dominating, especially Gymnodiniales. Multiple small phytoplankton, including Prymnesiophyceae and Prasinophyceae, were also identified, which complements the previous lack of identifying small phytoplankton and those unstable after fixation. Of the top 20 phytoplankton genera identified, 15 were HAB-forming genera, which accounted for 47.3%-71.5% of the relative abundance of phytoplankton. Based on long-read metabarcoding, a total of 147 OTUs (PID > 97%) belonging to phytoplankton were identified at the species level, including 118 species. Among them, 37 species belonged to HAB-forming species, and 98 species were reported for the first time in the Beibu Gulf. Contrasting the two metabarcoding approaches at the class level, they both showed a predominance of Dinophyceae, and both included high abundances of Bacillariophyceae, Prasinophyceae, and Prymnesiophyceae, but the relative contents of the classes varied. Notably, the results of the two metabarcoding approaches were quite different below the genus level. The high abundance and diversity of HAB species were probably due to their special life history and multiple nutritional modes. Annual HAB species variation revealed in this study provided a basis for evaluating their potential impact on aquaculture and even nuclear power plant safety in the Beibu Gulf.

Benthic foraminiferal response to the Oceanic Anoxic Event 2 (Late Cretaceous) and evidence of bottom water re‐oxygenation during the Plenus Cold Event at Clot Chevalier (Vocontian Basin, SE France)

The Cenomanian-Turonian boundary interval is characterized by environmental perturbations related to the Oceanic Anoxic Event 2 (OAE 2) that severely affected the marine biota, including benthic and planktonic foraminifera. We present a continuous high-resolution benthic foraminiferal record in combination with published planktonic foraminiferal and geochemical data across the Cenomanian-Turonian boundary interval in the Clot Chevalier section (Vocontian Basin, SE France) with the aim to interpret paleoceanographic changes in bottom waters. Benthic foraminiferal assemblages are characterized by low diversity and indicate an outer shelf-upper bathyal environment. Changes in composition and abundance of the benthic assemblages throughout the stratigraphic section allow identification of seven distinct environments. In the middle Cenomanian, below the OAE 2, benthic foraminifera show high species diversity and abundance of infaunal and epifaunal taxa, suggesting an environment characterized by oxic conditions at the seafloor. The microfossil assemblages in the upper Cenomanian within the OAE 2 interval are dominated by radiolaria (> 50%) followed by benthic calcareous taxa (Gavelinella sp., Gyroidinoides sp., Praebulimina elata, Tappanina laciniosa). Benthic agglutinated taxa (Ammobaculites sp., Ammodiscus cretaceus, Gaudryina sp., Textulariopsis bettenstaedti) show high abundance in the lowest part of the OAE 2 and disappear close to the top of the interval. The assemblage composition and the highest values of Total Organic Carbon (TOC) registered in this interval suggest eutrophication and suboxic conditions at the seafloor. However, at ∼1 m above the onset of the OAE 2, the repopulation by inferred oxic benthic foraminiferal taxa (i.e., Frondicularia sp. and Ramulina aculeata) suggests ventilation of bottom water masses, recording the Plenus Cold Event (PCE). In the lowermost Turonian, the assemblages exhibit high species diversity and abundance with the re-appearance of calcareous taxa, indicating oxic conditions, and of agglutinated taxa associated to moderate oxygen concentrations. Results show that the distribution of benthic foraminifera follows fluctuations in oxygenation and carbon export flux at the seafloor interpreted as the environmental changes associated to the onset of the OAE 2 and of the PCE across the Cenomanian-Turonian boundary interval.

Visible to near-infrared reflectance and Raman spectra of evaporites from sulfate-chloride Mars analogue brines

While much attention has been given to the identification and characterization of single-phase salts on Mars, relatively little has been applied to mixed evaporative assemblages. Given the likely existence of these assemblages on Mars (e.g., basin deposits) and the lack of data on their spectral signatures, here we present an experimental study of multicomponent S and Cl-bearing Mars-relevant brines. We modeled, synthesized and evaporated brines in the laboratory under both martian and terrestrial (P, T, pCO2) environmental conditions, and characterized the resulting precipitates using Visible–Near Infrared (VNIR), Raman spectroscopy, XRD and SEM-EDS. We compared these results to mineral assemblages calculated using the FREZCHEM thermodynamic model. For mixed brines primarily containing Na+, K+, Mg2+, Ca2+, SO42− and Cl−, epsomite (MgSO4•7H2O) and bischofite (MgCl2•6H2O) overwhelm VNIR and Raman spectra, while anhydrous crystalline salts and Na- and K-sulfates are unidentified. Mg-sulfates are identifiable in the VNIR and Raman even at low or no modeled mass abundance in an evaporative assemblage and are often the only clearly identifiable salt. These results imply that regions of Mg-sulfate identification on Mars may have only minor amounts of Mg-sulfate present, and significant amounts of halides or other sulfates may be undetectable. This may be due to a combination of late-stage Mg-sulfate precipitation and non-linear spectral mixing. Raman is more sensitive than VNIR to the identification of Ca-sulfate salts in these mixed assemblages. We predict that high abundances of mixed chloride and sulfate salts species will be identified as the Curiosity Rover continues to explore the Sulfate Unit of Gale Crater, and note that the Perseverance rover offers the first opportunity to identify such mixed assemblages in Jezero Crater with this combination of techniques.

DNA metabarcoding on repeat: Sequencing data of marine macrobenthos are reproducible and robust across labs and protocols

DNA metabarcoding can be used in marine environmental monitoring if results are reproducible between labs and robust against modifications to the lab protocol. In this interlaboratory study, we conducted a ring test where subsamples of blended macrobenthos samples were distributed to four laboratories located in Belgium, the Netherlands, Germany and Denmark. Samples were processed by a standardized lab protocol and by an adapted protocol, and the resulting datasets were analyzed with the same bioinformatics pipeline. Different biodiversity indicators were calculated. Our results show that bulkDNA metabarcoding of marine macrobenthos offers a highly reproducible assessment of alpha diversity patterns when using a standardized protocol, since comparable species numbers, Shannon indices and Inverse Simpson indices were found between laboratories. Especially high abundant species and species with large body sizes were shared between the laboratories. The need for using a standardized protocol to enhance comparability in alpha diversity between different studies was shown. Beta diversity patterns are less subjected to changes in the metabarcoding protocol and were almost identical between different laboratories, as the main clustering was always based on the macrobenthic community, independent of the used protocol or the laboratory that conducted the work. We conclude that DNA metabarcoding for marine environmental monitoring is an appropriate method when the aim is to study changes in community patterns and advocate its implementation in routine monitoring programs of national and European authorities, providing that a standardized protocol is implemented and/or a detailed description of the protocol is available.

A checklist of wild mushroom diversity and distribution in the Jahangirnagar University campus area, Bangladesh

This comprehensive study focuses on a checklist survey of wild mushrooms and documents their morphological variability and diversity at Jahangirnagar University, a natural and social forest area in Bangladesh. Through field studies on the campus grounds from June to October 2021, 60 samples were collected from which 40 species were identified by morphological characters, belonging to 33 genera, 26 families, and 10 orders. Most species were identified from the order Agaricales and the highest frequency (83.33%) from the orders Polyporales and Agaricales. The highest species abundance was 83.33% for Ganoderma spp., Crepidotus applanatus and the density was 70% for Marasmiellus candidus. The dominant species were Ganoderma spp., Coprinus disseminates, Marasmius spp., Schizophyllum commune, Calvulina coralloides. The wild mushrooms were prevalent in the natural forest areas of the Jahangirnagar University campus. As far as we are aware, this report is the very first work on wild mushrooms or macro-fungi on the campus of Jahangirnagar University. This survey shows that the campus grounds are enriched with a wide variety of wild mushrooms.
 Jahangirnagar University J. Biol. Sci. 11(1 & 2): 41-67, 2022 (June & December)

Cervicovaginal Microbiota Profiles in Precancerous Lesions and Cervical Cancer among Ethiopian Women.

Although high-risk human papillomavirus infection is a well-established risk factor for cervical cancer, other co-factors within the local microenvironment may play an important role in the development of cervical cancer. The current study aimed to characterize the cervicovaginal microbiota in women with premalignant dysplasia or invasive cervical cancer compared with that of healthy women. The study comprised 120 Ethiopian women (60 cervical cancer patients who had not received any treatment, 25 patients with premalignant dysplasia, and 35 healthy women). Cervicovaginal specimens were collected using either an Isohelix DNA buccal swab or an Evalyn brush, and ribosomal RNA sequencing was used to characterize the cervicovaginal microbiota. Shannon and Simpson diversity indices were used to evaluate alpha diversity. Beta diversity was examined using principal coordinate analysis of weighted UniFrac distances. Alpha diversity was significantly higher in patients with cervical cancer than in patients with dysplasia and in healthy women (p < 0.01). Beta diversity was also significantly different in cervical cancer patients compared with the other groups (weighted UniFrac Bray-Curtis, p < 0.01). Microbiota composition differed between the dysplasia and cervical cancer groups. Lactobacillus iners was particularly enriched in patients with cancer, and a high relative abundance of Lactobacillus species was identified in the dysplasia and healthy groups, whereas Porphyromonas, Prevotella, Bacteroides, and Anaerococcus species predominated in the cervical cancer group. In summary, we identified differences in cervicovaginal microbiota diversity, composition, and relative abundance between women with cervical cancer, women with dysplasia, and healthy women. Additional studies need to be carried out in Ethiopia and other regions to control for variation in sample collection.

Low species turnover of upland Amazonian birds in the absence of physical barriers

AbstractAimOne of the oldest and most powerful ways for ecologists to explain distinct biological communities is to invoke underlying environmental differences. But in hyper‐diverse systems, which often display high species richness and low species abundance, these sorts of community comparisons are especially challenging. The classic view for Amazonian birds posits that riverine barriers and habitat specialization determine local and regional community composition. We test the tacit, complementary assumption that similar bird communities should therefore permeate uniform habitat between major rivers, regardless of distance.LocationUpland (terra firme) rainforests of central Amazonia.MethodsWe conducted intensive whole‐community surveys of birds in three pairs of 100‐ha plots, separated by 40–60 km. We then used dissimilarity indices, cluster analysis, and ordination to characterize differences among the six avian communities.ResultsIn all, we detected 244 forest‐dependent birds, with an average of 190 species (78%) per plot. Species turnover was negligible, no unique indicator species were found among plot pairs, and all documented species were already known from a complete inventory at one of the three sites.Main ConclusionsOur study corroborates the classic biogeographical pattern and suggests that turnover contributes little to regional avian diversity within upland forests. Using a grain size of 100 ha, this implies that upland birds perceive the environment as uniform, at least over distances of ~60 km. Therefore, to maximize both local species richness and population persistence, our findings support the conservation of very large tracts of upland rainforest. Our analyses also revealed that the avifauna at Reserva Ducke, encroached by urban sprawl from the city of Manaus, shows the hallmarks of a disturbed community, with fewer vulnerable insectivores. This defaunation signals that even an enormous preserve (10 × 10 km) in lowland Amazonia is not insulated from anthropogenic degradation within the surrounding landscape.

Seasonal variation in prey preference, diet partitioning and niche breadth in a rich large carnivore guild

AbstractLarge carnivore community structure is affected by direct and indirect interactions between intra‐guild members. Co‐existence between different species within a carnivore guild may occur through diet, habitat or temporal partitioning. Since carnivore species are highly dependent on availability and accessibility of prey, diet partitioning is potentially one of the most important mechanisms in allowing carnivores to co‐exist. Intra‐guild interactions may vary over time as carnivore prey preference and diet overlap can change due to seasonal changes in resource availability. We conducted scat analysis to compare the seasonal changes in prey preference, diet partitioning and niche breadth of four large carnivore species, namely leopard Panthera pardus, spotted hyena Crocuta crocuta, brown hyena Parahyaena brunnea and wild dog Lycaon pictus in central Tuli, Botswana. Large carnivores in central Tuli display a high dietary overlap, with spotted hyena and brown hyena displaying almost complete dietary overlap and the other carnivore species displaying slightly lower but still significant dietary overlap. Dietary niche breadth for both hyena species was high possibly due to their flexible foraging strategies, including scavenging, while leopard and wild dog showed a relatively low niche breadth, suggesting a more specialised diet. High dietary overlap in central Tuli is possibly explained by the high abundance of prey species in the area thereby reducing competition pressure between carnivore species. Our research highlights the need to assess the influence of diet partitioning in structuring large carnivore communities across multiple study sites, by demonstrating that in prey rich environments, the need for diet partitioning by carnivores to avoid competition may be limited.

Demography and spatial distribution of a threatened species from the Atlantic Forest in southern Brazil: differences between urban and rural remnants.

Logging and agricultural exploitation have led to the degradation of Araucaria Forest remnants and the alteration of its last preserved patches. This forest typology contains many endangered plant species, as is the case of the tree Oreopanax fulvus Marchal. To support conservation of this species and understand how different landscape matrices can influence its populations, we evaluated the demographic structure and spatial distribution of O. fulvus in two Araucaria Forest remnants in Paraná state. We delimited two plots (urban and rural population), each with 1 ha, subdivided them into 100 subplots (10 x 10 m), and recorded diameter at ground level (DGL), height, and coordinates of two post-germinative developmental stage of individuals. In each subplot, we measured slope, luminosity, and canopy height. We used Ripley's K function analysis to describe distribution patterns of the species and the spatial relationship between mature and juvenile trees. We performed correlations between abundance and environmental and structural variables of the O. fulvus populations. Abundance varied between remnants, from 183 individuals/ha (12 mature and 171 juvenile) to 1306 individuals/ha (10 and 1296). The remnants varied in abundance and plant frequency. The species showed an investment in seedling banks. Most juvenile had DGL up to 3.0 cm and height up to 1.0 m and presented aggregated spatial distribution, while adults had random distribution. In the rural population juvenile abundance were correlated with canopy height (positively) and distance to mature trees (negatively). The slope was correlated for both sites, but oppositely, indicating that other factors might have interfered in the regeneration abundance. The urban remnant showed a high abundance of this endangered species, calling attention for potential studies in urban arborization, management and conservation of these remnants.