Search results for: species distribution models

Authors: Zahira Belkacemi

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One of the most important tools in conservation biology is information on the geographic distribution of species and the variables determining those patterns. In this study, we used maximum-entropy niche modeling (Maxent) to predict the current and future distribution of Anthus pratensis using climatic variables. The results showed that the species would not be highly affected by the climate change in shifting its distribution; however, the results of this study should be improved by taking into account other predictors, and that the NATURA 2000 protected sites will be efficient at 42% in protecting the species.

Keywords: anthus pratensis, climate change, Europe, species distribution model

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Authors: Camille Van Eupen, Dirk Maes, Marc Herremans, Kristijn R. R. Swinnen, Ben Somers, Stijn Luca

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In ecology, species distribution models are commonly implemented to study species-environment relationships. These models increasingly rely on opportunistic citizen science data when high-quality species records collected through standardized recording protocols are unavailable. While these opportunistic data are abundant, uncertainty is usually high, e.g., due to observer effects or a lack of metadata. Data quality filtering is often used to reduce these types of uncertainty in an attempt to increase the value of studies relying on opportunistic data. However, filtering should not be performed blindly. In this study, recommendations are built for data quality filtering of opportunistic species occurrence data that are used as input for species distribution models. Using an extensive database of 5.7 million citizen science records from 255 species in Flanders, the impact on model performance was quantified by applying three data quality filters, and these results were linked to species traits. More specifically, presence records were filtered based on record attributes that provide information on the observation process or post-entry data validation, and changes in the area under the receiver operating characteristic (AUC), sensitivity, and specificity were analyzed using the Maxent algorithm with and without filtering. Controlling for sample size enabled us to study the combined impact of data quality filtering, i.e., the simultaneous impact of an increase in data quality and a decrease in sample size. Further, the variation among species in their response to data quality filtering was explored by clustering species based on four traits often related to data quality: commonness, popularity, difficulty, and body size. Findings show that model performance is affected by i) the quality of the filtered data, ii) the proportional reduction in sample size caused by filtering and the remaining absolute sample size, and iii) a species ‘quality profile’, resulting from a species classification based on the four traits related to data quality. The findings resulted in recommendations on when and how to filter volunteer generated and opportunistically collected data. This study confirms that correctly processed citizen science data can make a valuable contribution to ecological research and species conservation.

Keywords: citizen science, data quality filtering, species distribution models, trait profiles

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Authors: Champika S. Kariyawasam

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The distribution of gorse (Ulex europaeus) plants in South Australia has been modelled using 126 presence-only location data as a function of seven climate parameters. The predicted range of U. europaeus is mainly along the Mount Lofty Ranges in the Adelaide Hills and on Kangaroo Island. Annual precipitation and yearly average aridity index appeared to be the highest contributing variables to the final model formulation. The Jackknife procedure was employed to identify the contribution of different variables to gorse model outputs and response curves were used to predict changes with changing environmental variables. Based on this analysis, it was revealed that the combined effect of one or more variables could make a completely different impact to the original variables on their own to the model prediction. This work also demonstrates the need for a careful approach when selecting environmental variables for projecting correlative models to climatically distinct area. Maxent acts as a robust model when projecting the fitted species distribution model to another area with changing climatic conditions, whereas the generalized linear model, bioclim, and domain models to be less robust in this regard. These findings are important not only for predicting and managing invasive alien gorse in South Australia and Sri Lanka but also in other countries of the invasive range.

Keywords: invasive species, Maxent, species distribution modelling, Ulex europaeus

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Authors: M. Bounechada, M. Fenni, S. Bouharati, S. E. Doumandji

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The study was taken in Setif region (36° 11' 29 N and 5° 24' 34 E) located at the north-eastern of Algeria. This paper recorded and discusses zoogeography and host plant relationships of Setifian species Alticinae subfamily. A total of 50 species belonging to Alticinae subfamily of Chrysomelidae which is the economically important familty, were recorded from differentes localities of Setif region. They are included in 10 genera. Genera Longitarsus Berthold, 1827 is less species-rich than the other Alticinae genera captured. It represens about 38% of the all species collected. Cruciferae and Compositae were the mostly prefered host plant families representing Alticinae species. For each species we mentioned the collecting sites, geographical distribution and the host plants.

Keywords: Algeria, Alticinae, Chrysomelidae, Coleoptera, distribution, host plants, species composition, Setif

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Authors: Tamirat Solomon, Tadesse Faltamo, Belete Limani

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This study was conducted on the mountain Damota of Wolaita to assess the abundance and spatial distribution of two locally important indigenous medicinal plants on the mountain landscape. A total of 130 plots measuring 20x20m were established along eight systematically laid transect lines. In each plot, the abundance and distribution of Hagenia abyssinica (tree) and Pentas schiperiana Vatke (shrub) were evaluated. The abundance and distribution of H. abyssinica were evaluated by measuring height and DBH for mature trees and counting seedlings and saplings, whereas the P. schiperiana Vatke was assessed for its abundance and distribution by counting in each plot. In the entire study plots, a total of 485 H. abyssinica and 760 P. schiperiana vatake were recorded. It was observed that the distribution of the species increased while the altitude increased and the highest abundance of the species was recorded at an altitude range between 2332 and 2661m.a.s.l. However, at the altitudes below 2320 m.a.s.l., the species distributions and abundance was decreased, indicating either the ecological preference of the species or the extraction of the local community surrounding the mountain influenced the species. On average, only 28 seedlings/ha of H. abyssinica and 146/ha of P. schiperiana vatke were recorded in the study areas showing the tendency of decline in the abundance and distribution of both species. Finally, we recommend management intervention for the socially important species which are under threat on the mountain landscape.

Keywords: indigenous medicinal plants, H.abyssinic, P. schiperiana, distribution, abundance, socio-economic importance

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Authors: Nurtazin Sabir, Begon Michael, Yeszhanov Aidyn, Alexander Belyaev, Hughes Nelika, Bethany Levick, Salmurzauly Ruslan

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This paper describes the features of the distribution of the most abundant species of fleas that are carriers of the most dangerous infections in the Balkhash-Alakol depression of Kazakhstan. We show that of 153 species of fleas described in the territory of the great gerbil (Rhombomys opimus Licht.), 35 species are parasitic. 21 of them are specific to gerbils species, and four species of fleas from the Xenopsylla genus are dominant in number and value of epizootic. We also describe the modern features of habitats of these species and their relationship with the great gerbil populations found in the South Balkhash region. It indicates the need for research on the population structure of the most abundant fleas species and their relationship with the structure of the populations of main carrier of transmission infections in the region-great gerbil.

Keywords: Balkhash-Alakol depression, natural foci of plague, species diversity and distribution of fleas, flea and great gerbil population structure, epizootic activity, mass species of fleas

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Authors: Katyana A. Vert-Pre, James T. Thorson, Thomas Trancart, Eric Feunteun

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In marine ecosystems, spatial and temporal species structure is an important component of ecosystems’ response to anthropological and environmental factors. Although spatial distribution patterns and fish temporal series of abundance have been studied in the past, little research has been allocated to the joint dynamic spatio-temporal functional patterns in marine ecosystems and their use in multispecies management and conservation. Each species represents a function to the ecosystem, and the distribution of these species might not be random. A heterogeneous functional distribution will lead to a more resilient ecosystem to external factors. Applying a Vector-Autoregressive Spatio-Temporal (VAST) model for count data, we estimate the spatio-temporal distribution, shift in time, and abundance of 140 species of the Eastern English Chanel, Bay of Biscay and Mediterranean Sea. From the model outputs, we determined spatio-temporal clusters, calculating p-values for hierarchical clustering via multiscale bootstrap resampling. Then, we designed a functional map given the defined cluster. We found that the species distribution within the ecosystem was not random. Indeed, species evolved in space and time in clusters. Moreover, these clusters remained similar over time deriving from the fact that species of a same cluster often shifted in sync, keeping the overall structure of the ecosystem similar overtime. Knowing the co-existing species within these clusters could help with predicting data-poor species distribution and abundance. Further analysis is being performed to assess the ecological functions represented in each cluster.

Keywords: cluster distribution shift, European marine ecosystems, functional distribution, spatio-temporal model

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Authors: Karina Reiter, Stefan Dullinger, Christoph Plutzar, Dietmar Moser

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Due to population growth and changing patterns of production and consumption, the demand for natural resources and, as a result, the pressure on Earth’s ecosystems are growing. Biodiversity mapping can be a useful tool for assessing species endangerment or detecting hotspots of extinction risks. This paper explores the benefits of using the change in trophic energy flows as a consequence of the human alteration of the biosphere in biodiversity mapping. To this end, multiple linear regression models were developed to explain species richness in areas where there is no human influence (i.e. wilderness) for three taxonomic groups (birds, mammals, amphibians). The models were then applied to predict (I) potential global species richness using potential natural vegetation (NPPpot) and (II) global ‘actual’ species richness after biomass appropriation using NPP remaining in ecosystems after harvest (NPPeco). By calculating the difference between predicted potential and predicted actual species numbers, maps of estimated species richness loss were generated. Results show that biomass appropriation for human use can indeed be linked to biodiversity loss. Areas for which the models predicted high species loss coincide with areas where species endangerment and extinctions are recorded to be particularly high by the International Union for Conservation of Nature and Natural Resources (IUCN). Furthermore, the analysis revealed that while the species distribution maps of the IUCN Red List of Threatened Species used for this research can determine hotspots of biodiversity loss in large parts of the world, the classification system for threatened and extinct species needs to be revised to better reflect local risks of extinction.

Keywords: biodiversity loss, biomass harvest, human appropriation of net primary production, species richness

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Authors: Malay K. Pramanik

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Climate change is continuously affecting the ecosystem, species distribution as well as global biodiversity. The assessment of the species potential distribution and the spatial changes under various climate change scenarios is a significant step towards the conservation and mitigation of habitat shifts, and species' loss and vulnerability. In this context, the present study aimed to predict the influence of current and future climate on an ecologically vulnerable medicinal species, Garcinia gummi-gutta, of the southern Western Ghats using Maximum Entropy (MaxEnt) modeling. The future projections were made for the period of 2050 and 2070 with RCP (Representative Concentration Pathways) scenario of 4.5 and 8.5 using 84 species occurrence data, and climatic variables from three different models of Intergovernmental Panel for Climate Change (IPCC) fifth assessment. Climatic variables contributions were assessed using jackknife test and AOC value 0.888 indicates the model perform with high accuracy. The major influencing variables will be annual precipitation, precipitation of coldest quarter, precipitation seasonality, and precipitation of driest quarter. The model result shows that the current high potential distribution of the species is around 1.90% of the study area, 7.78% is good potential; about 90.32% is moderate to very low potential for species suitability. Finally, the results of all model represented that there will be a drastic decline in the suitable habitat distribution by 2050 and 2070 for all the RCP scenarios. The study signifies that MaxEnt model might be an efficient tool for ecosystem management, biodiversity protection, and species re-habitation planning under climate change.

Keywords: Garcinia gummi gutta, maximum entropy modeling, medicinal plants, climate change, western ghats, MaxEnt

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Authors: Mostafa R. Sharaf, Shehzad Salman, Hathal M. Al Dhafer, Shahid A. Akbar, Abdulrahman S. Aldawood

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The ant genus Trichomyrmex Mayr is revised for the Arabian Peninsula based on the worker caste. Nine species are recognized and descriptions of two new species, T. almosayari sp. n. and T. shakeri sp. n. from Riyadh Province, the Kingdom of Saudi Arabia (KSA) are given. A key to species and diagnostic characters of the treated species are presented. New country records are presented, T. abyssinicus (Forel) for the KSA and T. destructor (Jerdon) and T. mayri (Forel) for the State of Qatar. New distribution records for T. destructor (Jerdon) and T. mayri (Forel) in the KSA are provided. Regional and world distributions, and distribution maps for the treated species are included. Ecological and biological data are given where known.

Keywords: ants, Trichomyrmex, Arabian Peninsula, T. almosayari, T. shakeri

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Authors: Masoud Sheidaei, Fahimeh Koohdar

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Date palms are economically important tree plants with high nutrition and medicinal values. More than 400 date palm cultivars are cultivated in many regions of Iran, but no report is available on landscape genetics and species distribution modeling of these trees from the country. Therefore, the present study provides a detailed insight into the genetic diversity and structure of date palm populations in Iran and investigates the effects of geographical and climatic variables on the structuring of genetic diversity in them. We used different computational methods in the study like, spatial principal components analysis (sPCA), redundancy analysis (RDA), latent factor mixed model (LFMM), and Maxent and Dismo models of species distribution modeling. We used a combination of different molecular markers for this study. The results showed that both global and local spatial features play an important role in the genetic structuring of date palms, and the genetic regions associated with local adaptation and climatic variables were identified. The effects of climatic change on the distribution of these taxa and the genetic regions adaptive to these changes will be discussed.

Keywords: adaptive genetic regions, genetic diversity, isolation by distance, populations divergence

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Authors: Negar Ghotbeddin, Seied Mohammad Reza Fatemi, Tooraj Valinassab

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The samplings were carried out at 8 stations (Govatr, Pasabandar, Beriss, Ramin, Chabahar, Pozm, Gordim, and Meidani) in subtidal zones of Oman Sea during the year 2009-2010. The specimens were collected by trawl net and preserved in 70% alcohol. A total of 23 species belonged to 9 families and 15 genera were caught. The results of the present study revealed that families Portunidae had the highest species enriched with 9 species. Most of the species had high distribution in the west Indian Ocean (69.56%) and 8.69% of species were endemic. Almost species were similar to those found in the Persian Gulf.

Keywords: Brachyura, biogeography, subtidal, Oman Sea

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Authors: Tariq Mahmood, Faiza Lehrasab, Faraz Akrim, Muhammad Sajid nadeem, Muhammad Mushtaq, Unza waqar, Ayesha Sheraz, Shaista Andleeb

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Brown bear (Ursus arctos), a member of the family Ursidae, is distributed in a wide range of habitats in North America, Europe and Asia. Suspectedly, the global distribution range of brown bears is decreasing at the moment due to various factors. The carnivore species is categorized as ‘Least Concern’ globally by the IUCN Red List of Threatened Species. However, there are some fragmented, small populations that are on the verge of extinction, as is in Pakistan, where the species is listed as ‘Critically Endangered’, with a declining population trend. Importantly, the global historical distribution range of brown bears is undocumented. Therefore, in the current study, we reconstructed and estimated the historical distribution range of brown bears using QGIS software and also analyzed the network of protected areas in the past and current ranges of the species. Results showed that brown bear was more widely distributed in historic times, encompassing 52.6 million km² area as compared to their current distribution of 38.8 million km², resulting in a total range contraction of up to approximately 28 %. In the past, a total of N = 62,234 protected Areas, covering approximately 3.89 million km² were present in the distribution range of the species, while now a total of N= 33,313 Protected Areas, covering approximately 2.75 million km² area, are present in the current distribution range of the brown bear. The brown bear distribution range in the protected areas has also contracted by 1.15 million km² and the total percentage reduction of PAs is 29%.

Keywords: brown bear, historic distribution, range contraction, protected areas

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Authors: Chad Goldsworthy, B. Rajeswari Matam

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The use of deep learning for species identification in camera trap images has revolutionised our ability to study, conserve and monitor species in a highly efficient and unobtrusive manner, with state-of-the-art models achieving accuracies surpassing the accuracy of manual human classification. The high imbalance of camera trap datasets, however, results in poor accuracies for minority (rare or endangered) species due to their relative insignificance to the overall model accuracy. This paper investigates the use of Focal Loss, in comparison to the traditional Cross Entropy Loss function, to improve the identification of minority species in the “255 Bird Species” dataset from Kaggle. The results show that, although Focal Loss slightly decreased the accuracy of the majority species, it was able to increase the F1-score by 0.06 and improve the identification of the bottom two, five and ten (minority) species by 37.5%, 15.7% and 10.8%, respectively, as well as resulting in an improved overall accuracy of 2.96%.

Keywords: convolutional neural networks, data imbalance, deep learning, focal loss, species classification, wildlife conservation

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Authors: Imen Labidi, Said Nouira

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Dung beetles Scarabaeides of Tunisia constitute a major component of soil fauna, especially in the Mediterranean region. In the first phase of the present study, an intensive investigation of this group following the gathering of all the bibliographic, museological data and based on a recent collection of 17020 specimens in 106 localities in Tunisia, allowed to confirm with certainty the presence of 94 species distributed in 43 genera, 4 families and 3 sub-families. Only 81 species distributed in 38 genres, 4 families, and 3 sub-families, have been found during our prospections. The population of dung beetles Scarabaeides is composed of 58% of Aphodiidae, 39.51% of Scarabaeidae, and 8.64% of Geotrupidae. Biogeographic affinities of the species were determined and showed that 42% of the identified species have a wide Palaearctic distribution, the endemism is very low, only 3 species are endemic to Tunisia Mecynodes demoflysi, Neobodilus marani, and Thorectes demoflysi, 29 species have a wide distribution, 35 are northern and 17 are southern species. Moreover, others are dependent on very specific Biotopes like Sisyphus schaefferi linked to the northwest of Tunisia and Scarabaeus semipunctatus related to the coastal area north of Tunisia.

Keywords: dung beetles, Tunisia, composition, biogeography

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Authors: Abdullahi Jibrin, Aishetu Abdulkadir

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The development of allometric models is crucial to accurate forest biomass/carbon stock assessment. The aim of this study was to develop a set of biomass prediction models that will enable the determination of total tree aboveground biomass for savannah woodland area in Niger State, Nigeria. Based on the data collected through biometric measurements of 1816 trees and destructive sampling of 36 trees, five species specific and one site specific models were developed. The sample size was distributed equally between the five most dominant species in the study site (Vitellaria paradoxa, Irvingia gabonensis, Parkia biglobosa, Anogeissus leiocarpus, Pterocarpus erinaceous). Firstly, the equations were developed for five individual species. Secondly these five species were mixed and were used to develop an allometric equation of mixed species. Overall, there was a strong positive relationship between total tree biomass and the stem diameter. The coefficient of determination (R2 values) ranging from 0.93 to 0.99 P < 0.001 were realised for the models; with considerable low standard error of the estimates (SEE) which confirms that the total tree above ground biomass has a significant relationship with the dbh. The F-test value for the biomass prediction models were also significant at p < 0.001 which indicates that the biomass prediction models are valid. This study recommends that for improved biomass estimates in the study site, the site specific biomass models should preferably be used instead of using generic models.

Keywords: allometriy, biomass, carbon stock , model, regression equation, woodland, inventory

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Authors: N. Norazlimi, R. Ramli

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A study was conducted to determine the diversity and abundance of shorebird species habituating the mudflat area of Jeram Beach and Remis Beach, Selangor, Peninsular Malaysia. Direct observation technique (using binoculars and video camera) was applied to record the presence of bird species in the sampling sites from August 2013 until July 2014. A total of 32 species of shorebird were recorded during both migratory and non-migratory seasons. Of these, eleven species (47.8%) are migrants, six species (26.1%) have both migrant and resident populations, four species (17.4%) are vagrants and two species (8.7%) are residents. The compositions of the birds differed significantly in all months (χ2=84.35, p<0.001). There is a significant difference in avian abundance between migratory and non-migratory seasons (Mann-Whitney, t=2.39, p=0.036). The avian abundance were differed significantly in Jeram and Remis Beaches during migratory periods (t=4.39, p=0.001) but not during non-migratory periods (t=0.78, p=0.456). Shorebird diversity was also affected by tidal cycle. There is a significance difference between high tide and low tide (Mann-Whitney, t=78.0, p<0.005). Frequency of disturbance also affected the shorebird distribution (Mann-Whitney, t=57.0, p= 0.0134). Therefore, this study concluded that tides and disturbances are two factors that affecting temporal distribution of shorebird in mudflats area.

Keywords: biodiversity, distribution, migratory birds, direct observation

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Authors: Hamisu Jibril

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The study explores changes in plant species composition along disturbance gradient in urban areas in Nigeria at Bayero University Kano campuses. The aim is to assess changes in plant species composition and distribution within a degraded dryland environment in Kano Metropolis, Nigeria. Vegetation sampling was conducted using plots quadrat and transect methods, and different plant species were identified in the three study sites. Data were analyzed using ANOVA, t-tests and conventional indices to compare species richness, evenness and diversity. The study found no significant differences in species frequency among sites or sampling methods but observed higher species richness, evenness and diversity values in grasses species compared to trees. The study addressed changes in plant species composition along a disturbance gradient in an urban environment, focusing on species richness, evenness, and diversity. The study contributes to understanding the vegetation dynamics in degraded urban environments and highlights the need for conservation efforts. The research also adds to the existing literature by confirming previous findings and suggesting re-planting efforts. The study suggests similarities in plant species composition between old and new campus areas and emphasizes the importance of further investigating factors leading to vegetation loss for conservation purposes.

Keywords: species diversity, urban kano, dryland environment, vegetation sampling

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Authors: Mohamed Thani Ibouroi, Ali Cheha, Claudine Montgelard, Veronique Arnal, Dawiyat Massoudi, Guillelme Astruc, Said Ali Ousseni Dhurham, Aurelien Besnard

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The Livingstone's flying fox (Pteropus livingstonii) and the Comorian fruit bat (P.seychellensis comorensis) are two endemic fruit bat species among the mostly threatened animals of the Comoros archipelagos. Despite their role as important ecosystem service providers like all flying fox species as pollinators and seed dispersers, little is known about their ecologies, population genetics and structures making difficult the development of evidence-based conservation strategies. In this study, we assess spatial distribution and ecological niche of both species using Species Distribution Modeling (SDM) based on the recent Ensemble of Small Models (ESMs) approach using presence-only data. Population structure and genetic diversity of the two species were assessed using both mitochondrial and microsatellite markers based on non-invasive genetic samples. Our ESMs highlight a clear niche partitioning of the two sympatric species. Livingstone’s flying fox has a very limited distribution, restricted on steep slope of natural forests at high elevation. On the contrary, the Comorian fruit bat has a relatively large geographic range spread over low elevations in farmlands and villages. Our genetic analysis shows a low genetic diversity for both fruit bats species. They also show that the Livingstone’s flying fox population of the two islands were genetically isolated while no evidence of genetic differentiation was detected for the Comorian fruit bats between islands. Our results support the idea that natural habitat loss, especially the natural forest loss and fragmentation are the important factors impacting the distribution of the Livingstone’s flying fox by limiting its foraging area and reducing its potential roosting sites. On the contrary, the Comorian fruit bats seem to be favored by human activities probably because its diets are less specialized. By this study, we concluded that the Livingstone’s flying fox species and its habitat are of high priority in term of conservation at the Comoros archipelagos scale.

Keywords: Comoros islands, ecological niche, habitat loss, population genetics, fruit bats, conservation biology

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Authors: Stephanie Watson, Fabrice Stephenson, Conrad Pilditch, Carolyn Lundquist

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Spatial data detailing both the distribution and density of functionally important marine species are needed to inform management decisions. Species distribution models (SDMs) have proven helpful in this regard; however, models often focus only on species occurrences derived from spatially expansive datasets and lack the resolution and detail required to inform regional management decisions. Boosted regression trees (BRT) were used to produce high-resolution SDMs (250 m) at two spatial scales predicting probability of occurrence, abundance (count per sample unit), density (count per km2) and uncertainty for seven coastal seafloor taxa that vary in habitat usage and distribution to examine prediction differences and implications for coastal management. We investigated if small scale regionally focussed models (82,000 km2) can provide improved predictions compared to data-rich national scale models (4.2 million km2). We explored the variability in predictions across model type (occurrence vs abundance) and model scale to determine if specific taxa models or model types are more robust to geographical variability. National scale occurrence models correlated well with broad-scale environmental predictors, resulting in higher AUC (Area under the receiver operating curve) and deviance explained scores; however, they tended to overpredict in the coastal environment and lacked spatially differentiated detail for some taxa. Regional models had lower overall performance, but for some taxa, spatial predictions were more differentiated at a localised ecological scale. National density models were often spatially refined and highlighted areas of ecological relevance producing more useful outputs than regional-scale models. The utility of a two-scale approach aids the selection of the most optimal combination of models to create a spatially informative density model, as results contrasted for specific taxa between model type and scale. However, it is vital that robust predictions of occurrence and abundance are generated as inputs for the combined density model as areas that do not spatially align between models can be discarded. This study demonstrates the variability in SDM outputs created over different geographical scales and highlights implications and opportunities for managers utilising these tools for regional conservation, particularly in data-limited environments.

Keywords: Benthic ecology, spatial modelling, multi-scalar modelling, marine conservation.

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Authors: Raees Khan, Mir A. Khan, Sheikh Z. Ul Abidin, Abdul S. Mumtaz

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In the present study, phytogeography and conservation status of gymnosperms of Pakistan were investigated. 44 gymnosperms species of 18 genera and 9 families were collected from 66 districts of the country. Among the 44 species, 20 species were native (wild) and 24 species were exotic (cultivated). Ephedra sarocarpa of Ephedraceae was not collected in this study from its distribution area and most probably it may be Nationally Extinct now from this area. Previously in Gymnosperms Flora of Pakistan 34 species was reported. 12 new gymnosperms species were recorded for the first time. Pinus wallichiana (40 districts), Cedrus deodara (39 districts) Pinus roxburghii (36 districts), Picea smithiana (36 districts) and Abies pindrow (34 districts) have the maximum ecological amplitude. Juniperus communis (17districts) and Juniperus excelsa (14 districts) were the widely distributed among the junipers. Ephedra foliata (23 districts), Ephedra gerardiana (20 districts) and Ephedra intermedia (19 districts) has the widest distribution range. Taxus fuana was also wider distribution range and recorded in 19 districts but its population was not very stable. These species was recorded to support local flora and fuana, especially endemics. PCORD version 5 clustered all gymnosperms species into 4 communities and all localities into 5 groups through cluster analyses. The Two Way Cluster Analyses of 66 districts (localities) resulted 4 various plant communities. The Gymnosperms in Pakistan are distributed in 3 floristic regions i.e. Western plains of the country, Northern and Western mountainous regions and Western Himalayas. The assessment of the National conservation status of these species, 10 species were found to be threatened, 6 species were endangered, 4 species were critically endangered and 1 species have become extinct (Ephedra sarcocarpa). The population of some species i.e. Taxus fuana, Ephedra gerardiana, Ephedra monosperma, Picea smithiana and Abies spectabilis is decreasing at an alarming rate.

Keywords: conservation status, gymnosperms, phytogeography, Pakistan

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Authors: Mohd Tariq, Shyamal K. Nandi, Indra D. Bhatt

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Paris polyphylla Smith (Family- Liliaceae; English name-Love apple: Local name- Satuwa) is an important folk medicinal herb of the Indian subcontinent, being a source of number of bioactive compounds for drug formulation. The rhizomes are widely used as antihelmintic, antispasmodic, digestive stomachic, expectorant and vermifuge, antimicrobial, anti-inflammatory, heart and vascular malady, anti-fertility and sedative. Keeping in view of this, the species is being constantly removed from nature for trade and various pharmaceuticals purpose, as a result, the availability of the species in its natural habitat is decreasing. In this context, it would be pertinent to conserve this species and reintroduce them in its natural habitat. Predictive distribution modelling of this species was performed in Western Himalayan Region. One such recent method is Ecological Niche Modelling, also popularly known as Species distribution modelling, which uses computer algorithms to generate predictive maps of species distributions in a geographic space by correlating the point distributional data with a set of environmental raster data. In case of P. polyphylla, and to understand its potential distribution zones and setting up of artificial introductions, or selecting conservation sites, and conservation and management of their native habitat. Among the different districts of Uttarakhand (28°05ˈ-31°25ˈ N and 77°45ˈ-81°45ˈ E) Uttarkashi, Rudraprayag, Chamoli, Pauri Garhwal and some parts of Bageshwar, 'Maximum Entropy' (Maxent) has predicted wider potential distribution of P. polyphylla Smith. Distribution of P. polyphylla is mainly governed by Precipitation of Driest Quarter and Mean Diurnal Range i.e., 27.08% and 18.99% respectively which indicates that humidity (27%) and average temperature (19°C) might be suitable for better growth of Paris polyphylla.

Keywords: biodiversity conservation, Indian Himalayan region, Paris polyphylla, predictive distribution modelling

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Authors: Yousef Naserzadeh, Niloufar Mahmoudi

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The spotted-wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), a vinegar fly native to South East Asia, has recently invaded Europe, North- and South America and is spreading rapidly. Species distribution modeling has been widely employed to indicate probable areas of invasion and to guide management strategies. Drosophila sp. is native to Asia, but since 2015, it has invaded almost every country in the world, including Africa, Australia, India, and most recently, the Americas. The growth of this species of Drosophila suzukii has been rapidly multiplying and spreading in the last decade. In fact, we examine and model the potential geographical distribution of D. suzukii for both present and future scenarios. Finally, we determine the environmental variables that affect its distribution, as well as assess the risk of encroachment on protected areas. D.suzukii has the potential to expand its occurrence, especially on continents that have already been invaded. The predictive models obtained in this study indicate potential regions that could be at risk of invasion by D. suzukii, including protected areas. These results are important and can assist in the establishment of management plans to avoid the possible harm caused by biological invasions.

Keywords: climate change, Drosophila suzukii, environmental variables, host preference, host plant, nutrition

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Authors: Yosiya Chanta, Jantrararuk Tovaranont

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Species distribution model (SDMs) is one of the powerful tools used to create a suitability map used to predict and address ecology and conservation approaches. MaxEnt is a tool used among SDMs that is highly popular because it only uses presence data. Zanthoxylum rhetsa has more than 200 species distributed in the tropics. Most commonly found in cooler forest environments, there are 8-9 species found in Thailand. In northern Thailand, 3 varieties are commonly grown: Zanthoxylum myriacanthum, Zanthoxylum rhetsa and Zanthoxylum armatum. In the northern regions, these varieties are mainly used as a spice and as a cooking ingredient. MaxEnt has been used in this study to predict potential habitats for these Zanthoxylums in current and future times (2041and 2060). Suitable habitats are predicted using data from the EC-Earth3-Veg general circulation model with 19 climatic variables. The results indicate that the suitability of future habitats of Zanthoxylum rhetsa may expand into the lower northern part of Thailand. The habitat suitability map obtained from the MaxEnt tool shows that the Precipitation of Wettest Quarter (Bio16) is the most important climatic variable influencing the current and future spread of Zanthoxylum rhetsa.

Keywords: MaxEnt, Zanthoxylum rhets, species distribution modelling, climate change

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Authors: Dimpi A. Patel, Pankaj Raina, Ramesh Chinnasamy, Sunetro Ghosal

Abstract:

The herpetological fauna of Ladakh has been surveyed few times till 1999. In 2019, a rapid survey to document current herpetofaunal composition was undertaken in which a total of 6 species belonging to 2 orders and five families along with their altitudinal ranges were recorded. We present a revised checklist of reptiles found in Ladakh trans Himalayas based on historical records and recent field surveys. Records for erroneously reported species in literature are discussed and recommended for removal from the list from this region. For several species, new elevation range records have been recorded. This paper contributes to the present status of the richness of reptiles and amphibians in the region by documenting the composition and ecological distribution of the herpetofauna of unstudied sites. Species-specific temperature and humidity regimes were also recorded during the survey periods. Our study creates baseline information for future ecological and behavioral studies on the herpetofauna of the region by providing habitat preferences and distribution in detail.

Keywords: amphibians, distribution, diversity, reptiles, trans-Himalaya

Procedia PDF Downloads 129

Authors: Amy L. Irvine, Gabriel Reygondeau, Derek P. Tittensor

Abstract:

Marine protected areas (MPAs) within Canada’s exclusive economic zone help ensure the conservation and sustainability of marine ecosystems and the continued provision of ecosystem services to society (e.g., food, carbon sequestration). With ongoing and accelerating climate change, however, MPAs may become undermined in terms of their effectiveness at fulfilling these outcomes. Many populations of species, especially those at their thermal range limits, may shift to cooler waters or become extirpated due to climate change, resulting in new species compositions and ecological interactions within static MPA boundaries. While Canadian MPA management follows international guidelines for marine conservation, no consistent approach exists for adapting MPA networks to climate change and the resulting altered ecosystem conditions. To fill this gap, projected climate-driven shifts in species distributions on Canada’s east coast were analyzed to identify when native species emigrate and novel species immigrate within the network and how high mitigation and carbon emission scenarios influence these timelines. Indicators of the ecological changes caused by these species' shifts in the biological community were also developed. Overall, our research provides projections of climate change impacts and helps to guide adaptive management responses within the Canadian east coast MPA network.

Keywords: climate change, ecosystem modeling, marine protected areas, management

Procedia PDF Downloads 58

Authors: Seyedeh Belin Tavakoly Sany, Rosli Hashim, Majid Rezayi, Aishah Salleh, Omid Safari

Abstract:

The purpose of this paper is to describe the main characteristics of macroinvertebrate species in response to environmental forcing factors. Overall, 23 species of Mollusca, 4 species of Arthropods, 3 species of Echinodermata and 3 species of Annelida were identified at the 9 sampling stations during four sampling periods. Individual species of Mollusca constituted 36.4% of the total abundance, followed by Arthropods (27.01%), Annelida (34.3%) and Echinodermata (2.4%). The results of Kruskal-Wallis test indicated that a significant difference (p <0.05) in the abundance, richness and diversity of the macro-benthic community in different stations. The correlation analysis revealed that anthropogenic pollution and natural variability caused by these variations in spatial scales.

Keywords: benthic invertebrates, diversity, abundance, West Port

Procedia PDF Downloads 405

Authors: Wardatutthoyyibah, Satyawan Pudyatmoko, Sena Adi Subrata, Muhammad Ali Imron

Abstract:

The proboscis monkey is an endemic species to the island of Borneo with conservation status IUCN (The International Union for Conservation of Nature) of endangered. The population of the monkey has a specific habitat and sensitive to habitat disturbances. As a consequence of increasing rates of land-use change in the last four decades, its population was reported significantly decreased. We quantified the effect of land use change on the proboscis monkey’s habitat through the species distribution modeling (SDM) approach with Maxent Software. We collected presence data and environmental variables, i.e., land cover, topography, bioclimate, distance to the river, distance to the road, and distance to the anthropogenic disturbance to generate predictive distribution maps of the monkeys. We compared two prediction maps for 2000 and 2015 data to represent the current habitat of the monkey. We overlaid the monkey’s predictive distribution map with the existing protected areas to investigate whether the habitat of the monkey is protected under the protected areas networks. The results showed that almost 50% of the monkey’s habitat reduced as the effect of land use change. And only 9% of the current proboscis monkey’s habitat within protected areas. These results are important for the master plan of conservation of the endangered proboscis monkey and provide scientific guidance for the future development incorporating biodiversity issue.

Keywords: endemic species, land use change, maximum entropy, spatial distribution

Procedia PDF Downloads 122

Authors: Fatima Alkhayat, Abu Hassan Ahmed

Abstract:

Qatar as the one of Middle East and Gulf country is growing rapidly due to urbanization. Urbanization, population’s movement and goods transportation in addition to climatic change all together create suitable environments for remerging and/or introduction of new disease vectors species. Unfortunately, knowledge on mosquito species composition and their geographical distribution in Qatar is extremely limited. The objective of present study is to provide update information on species composition and distribution. Mosquito larval survey carried out in six sentinel sites in Qatar. The collection was made on monthly basis in period from October 2013 to May 2015 using dipping techniques and identified to species level using appropriate pictorial keys. In total about 3,085 mosquito larvae were collected and identified to species compromising three mosquito genera, Culex 87.4% (n=2697), Ochlerotatus 9.9% (n= 305) and Anopheles 2.6% (n= 81). Among Culex genera; Culex quinquefasciatus represent 87.8% (n= 2369), Cx. pipiens 8.7% (n=237), and Cx. mattinglyi 3.4% (n=91). Culex quinquefasciatus was the most commonly collected species, representing 93.5% in Alwakra (n= 2216) which was observed in November, December, March, April and May when reached the peak. 6.4% in Nuaija (n= 151) was found in February and March and reached the peak in March. 0.1% in Alkaraana (n=2) only observed in April. Cx. pipiens was observed 50.2% in Rwdat Alfaras (n=120) and 48.9% in Hazm Almurkhiya (n=117). While in Rowdat Alfaras it was observed in Oct-May and in Hazm Almurkhiya from Oct-April. Cx. mattinglyi (n= 91) was only found in Nuaija from October to December. Ochlerotatus genera account 1 species Oc. dorsalis (n=305). The majority of Oc. dorsalis were observed in March and May, 98% in Nuaija (n= 299), followed by 2% in Alkhor (n=6) which was observed in January and February. Anopheles was only represented by An. stephensi which was found 69% in Alwakra (n= 56) in November, December, April and May, while 25.9% in Hazm Almurkhiya (n=21) and found in May and November. 6.2% in Rwadat Alfaras and was observed only in November and 1.2% in Nuaija (n=1) and observed in October. Further investigation is required on the composition and distribution of mosquito for implementing a surveillance program and control of mosquito-borne diseases in Qatar.

Keywords: composition, distribution, mosquito, Qatar

Procedia PDF Downloads 252

Authors: Rafid Saeed Abdulrazak Alshkaki

Abstract:

In this paper, zero-one inflated negative binomial distribution is considered, along with some of its structural properties, then its parameters were estimated using the method of moments. It is found that the method of moments to estimate the parameters of the zero-one inflated negative binomial models is not a proper method and may give incorrect conclusions.

Keywords: zero one inflated models, negative binomial distribution, moments estimator, non negative integer sampling

Procedia PDF Downloads 255