scholarly journals Distribution, encounter rate and conservation status of Aquiloeurycea cafetalera (Caudata: Plethodontidae), a recently described Mexican salamander

2017 ◽  
Vol 16 (2) ◽  
pp. 211 ◽  
Author(s):  
José Luis Aguilar-López ◽  
Adriana Sandoval-Comte ◽  
Eduardo Pineda

The knowledge of the natural history of a species, its population traits and spatial distribution are essential to evaluate its risk of extinction and proposing strategies for its conservation. For poorly studied species inhabiting regions with a high degree of habitat conversion by anthropogenic activities, it is even more urgent to obtain this information. In this study, we carried out fieldwork and database analyses to obtain information on the ecology, natural history and spatial distribution of the plethodontid salamander Aquiloeurycea cafetalera, and we evaluated its conservation status according to the IUCN and the Mexican environmental agency (SEMARNAT). We found 109 individuals in 20 of the 43 localities visited (sampling effort = 1,174 person-hours). The salamander counts ranged from one to 21 individuals per locality and the average encounter rate was 21 salamanders per 100 person-hours of surveying, within a range from 2 to 117 salamanders. The current potential distribution calculated is about 2,000 km2 and fragmented, which means less than half of its original potential distribution. Our results suggest that it is necessary to include this species in biodiversity conservation programs because only a very small portion of its spatial distribution falls within natural protected areas.


2021 ◽  
pp. 1-9
Author(s):  
Nana Ismaila ◽  
Ulrich Maloueki

Accurate measures of animal population densities are essential to evaluate conservation status and implement action plans to ensure species survival. Gorilla numbers were assessed using the recce survey method within Moukalaba-Doudou National Park (MDNP) in Gabon using fresh nest counts of up to 1 week old. We walked 3,592 km within a 23.01-km<sup>2</sup> study site totalling a sampling effort of 297 days. Encounter rate was 0.12 fresh nests per kilometre, and gorilla density estimates generated by home range sizes (by minimal convex polygon) ranged between 1.14 and 1.48 gorillas/km<sup>2</sup>. Gorillas preferred mixed forest for nesting over other habitats (Cheason index value 1.31). Results showed that gorilla density values within the study area concurred with previous studies that used line transect methodologies. We conclude that the choice of sampling design is dependent on environmental conditions characterised by each habitat type and target species.



2020 ◽  
Vol 68 (4) ◽  
Author(s):  
Alejandro Solórzano ◽  
Mahmood Sasa

Introduction: The Black-headed Bushmaster (Lachesis melanocephala) is a large venomous snake that inhabits tropical moist forest, wet forest, montane and premontane wet forest in Southwestern Costa Rica and extreme Western Panama. Objective: We assign a neotype for the species due to the loss of the original holotype and update the information on its geographical distribution, natural history, and conservation status. Methods: To determine the conservation status of L. melanocephala, we modeled its potential distribution using the species` locality records and distribution modeling analysis implemented in MaxEnt. Based on the species’ potential distribution, we evaluate the loss of its original habitat and estimate the percentage of its distribution area that is currently protected by the country’s protected area system. Results: The potential distribution of the species was estimated at 10 139 km2, including areas where the species currently occurs and historical areas where the species has been registered but is nowadays considered locally extinct. About 29 % of that potential distribution overlaps with protected wild areas, so less than a third of the potential distribution of the species is under protection. Conclusions: During the last decade, accelerated habitat loss and growing evidence of declining natural populations indicate the need for urgent protective measures to prevent the extinction of this species in the foreseeable future.



Author(s):  
José Irving Monjarás-barrera ◽  
Mario Rocandio-rodríguez ◽  
Cristina Domínguez-castro ◽  
Francisco Reyes-zepeda ◽  
Sandra Grisell Mora-ravelo ◽  
...  

Ecological interactions between mites (predatory and phytophagous) and wild plants growing in undisturbed environments play a crucial role to understand their natural settlement, development and dispersion patterns. Pequin chili pepper, Capsicum annuum L. var. glabriusculum, is a low-cost natural resource for local communities living inside Natural Protected Areas (ANP) of Tamaulipas State in Mexico. The aims of this research work were: 1) determine the spatial distribution pattern of predatory and phytophagous mites, 2) determine the spatiotemporal association between predatory and phytophagous mites, and 3) determine the association among different mite species and some phenological stages of Pequin chili pepper. The most abundant phytophagous mites were Tetranychus merganser and Aculops lycpoersici, and the predatory species were Amblyseius similoides, Euseius mesembrinus and Metaseiulus (Metaseiulus) negundinis. Most mite species showed an aggregated distribution pattern according to the plant phenological stages. However, the distribution of mite species throughout time showed different types of aggregation. On the other hand, we found positive associations among A. lycopersici and T. merganser phytophagous mites with A. similoides, E. mesembrinus and M. (M.) negundinis predators mites. The association between plants and mite species were influenced by the phenological stages of Pequin chili pepper. This is an indication of the complexity among trophic-chain interactions that depend largely on the available resources and competition. These two factors serve as foundations for settlement, development and dispersion patterns of certain species.



2022 ◽  
Author(s):  
Gerard Gorman

This book details the natural history and cultural symbolism of a most unusual woodpecker – a species that neither excavates nest holes in trees, nor bores into wood to find insect prey. The elusive Wryneck is best renowned for performing a twisting, writhing head and neck display when threatened, but this ground-breaking study reveals many more secrets of its behaviour and evolution. Detailed information is presented on the species' origins, taxonomy, anatomy, appearance, moult, calls, distribution, conservation status, habitats, movements, breeding, diet and relationships, along with a chapter on its closest relative, the Red-throated Wryneck. The text is richly illustrated throughout with high quality photographs as well as sound spectrograms. This all-encompassing and engaging account has been written for a wide audience, whether professional ornithologist, citizen scientist, amateur birder, woodpecker aficionado and simply someone who wishes to learn more about this curious and remarkable bird.



Author(s):  
S.R. Chandramouli ◽  
K.V. Devi Prasad

The poorly-known, insular endemic frog species, Minervarya nicobariensis (Stoliczka, 1870) is re-described based on new material from the Nicobar Archipelago. A neotype is designated as its holotype had been lost. Novel data on biology, ecology, distribution and natural history of this poorly known species are provided. Breeding biology and larval morphology are described in detail. Potential threats to the species are discussed and an assessment of its conservation status is attempted.



Author(s):  
Barnaby Walker ◽  
Tarciso Leão ◽  
Steven Bachman ◽  
Eve Lucas ◽  
Eimear Nic Lughadha

Extinction risk assessments are increasingly important to many stakeholders (Bennun et al. 2017) but there remain large gaps in our knowledge about the status of many species. The IUCN Red List of Threatened Species (IUCN 2019, hereafter Red List) is the most comprehensive assessment of extinction risk. However, it includes assessments of just 7% of all vascular plants, while 18% of all assessed animals lack sufficient data to assign a conservation status. The wide availability of species occurrence information through digitised natural history collections and aggregators such as the Global Biodiversity Information Facility (GBIF), coupled with machine learning methods, provides an opportunity to fill these gaps in our knowledge. Machine learning approaches have already been proposed to guide conservation assessment efforts (Nic Lughadha et al. 2018), assign a conservation status to species with insufficient data for a full assessment (Bland et al. 2014), and predict the number of threatened species across the world (Pelletier et al. 2018). The wide range in sources of species occurrence records can lead to data quality issues, such as missing, imprecise, or mistaken information. These data quality issues may be compounded in databases that aggregate information from multiple sources: many such records derive from field observations (78% for plant species in GBIF; Meyer et al. 2016) largely unsupported by voucher specimens that would allow confirmation or correction of their identification. Even where voucher specimens do exist, different taxonomic or geographic information can be held for a single collection event represented by duplicate specimens deposited in different natural history collections. Tools are available to help clean species occurrence data, but these cannot deal with problems like specimen misidentification, which previous work (Nic Lughadha et al. 2019) has shown to have a large impact on preliminary assessments of conservation status. Machine learning models based on species occurrence records have been reported to predict with high accuracy the conservation status of species. However, given the black-box nature of some of the better machine learning models, it is unclear how well these accuracies apply beyond the data on which the models were trained. Practices for training machine learning models differ between studies, but more interrogation of these models is required if we are to know how much to trust their predictions. To address these problems, we compare predictions made by a machine learning model when trained on specimen occurrence records that have benefitted from minimal or more thorough cleaning, with those based on records from an expert-curated database. We then explore different techniques to interrogate machine learning models and quantify the uncertainty in their predictions.



2008 ◽  
Vol 23 (1) ◽  
pp. 1-4 ◽  
Author(s):  
Fanny M. Cornejo ◽  
Rolando Aquino ◽  
Carlos Jimenez


Zootaxa ◽  
2018 ◽  
Vol 4442 (4) ◽  
pp. 551 ◽  
Author(s):  
FLÁVIO KULAIF UBAID ◽  
LUÍS FABIO SILVEIRA ◽  
CESAR A. B. MEDOLAGO ◽  
THIAGO V. V. COSTA ◽  
MERCIVAL ROBERTO FRANCISCO ◽  
...  

Seed-finches are small-sized Neotropical granivorous birds characterized by extremely strong and thick beaks. Among these birds, the Great-billed Seed-Finch Sporophila maximiliani has been selectively and intensively trapped to the extent that has become one of the most endangered bird species in South America, yet its taxonomy remains complex and controversial. Two subspecies have been recognized: S. m. maximiliani (Cabanis, 1851), mainly from the Cerrado of central South America, and S. m. parkesi Olson (= Oryzoborus m. magnirostris), from northeastern South America. Originally, S. m. parkesi was diagnosed as being larger than the Large-billed Seed-Finch, S. c. crassirostris (Gmelin, 1789), but proper comparisons with S. m. maximiliani, which is larger than S. c. crassirostris, were never performed. Here we provide a review of the taxonomic and nomenclatural history of S. maximiliani, reevaluate the validity and taxonomic status of the subspecies based on morphological characters, and significantly revise its geographic distribution. Analyses based on plumage patterns and a Principal Component Analysis of morphometric characters indicated that S. m. parkesi is most appropriately treated as a synonym of the nominate taxon, which results in a monotypic S. maximiliani comprising two disjunct populations. Further, we conducted systematic searches for S. maximiliani in Brazil, in an attempt to obtain natural history information. After more than 6,000 hours of fieldwork in 45 areas of potential and historical occurrence, S. maximiliani was located only in two sites, in marshy environments called veredas, confirming the critical conservation status of this species, at least in Brazil. We discuss the conservation potential for, and the problems involved with, captive breeding of S. maximiliani for reintroduction into the wild. 



2019 ◽  
Vol 12 ◽  
pp. 117862211987277 ◽  
Author(s):  
Joan Nyika ◽  
Ednah Onyari

Groundwater is the most reliable resource for consumptive uses worldwide, but it is vulnerable to anthropogenic pollution in this post-industrialization era. Pollution of the resource may result from anthropogenic activities; hence, analysing the effects of leachate on groundwater is imperative. This study assessed the spatial distribution of physicochemical parameters of groundwater in Roundhill landfill vicinity of South Africa and conducted their hydrogeochemical analysis. Water samples were collected from 3 boreholes in the landfill surroundings and analysed for selected physicochemical characteristics. Spatial distribution of these parameters showed dominant pollution by Mn2+, Fe2+, and [Formula: see text], which surpassed prescribed allowable limits of the country in most of the study area. Possibilities of simple dissolution and ion mixing were deduced from the Durov diagram. Magnesium carbonate, sodium chloride, and mixed faces of groundwater were dominant in boreholes 1 to 3, respectively. The dominance of Ca2+, Cl−, Mg2+, and [Formula: see text] ions in some boreholes suggested anthropogenic pollution. Landfill leachate was associated with groundwater pollution in the study area.



2020 ◽  
Vol 12 (3) ◽  
pp. 1282 ◽  
Author(s):  
Hari Prasad Sharma ◽  
Bhagawat Rimal ◽  
Mingxia Zhang ◽  
Sandhya Sharma ◽  
Laxman Prasad Poudyal ◽  
...  

Anthropogenic activities have driven many wildlife species towards extinction. Among these species, the geographic distributions of many are poorly documented, which can limit the effectiveness of conservation. The critically endangered Chinese pangolin (Manis pentadactyla) is experiencing population decline throughout its range due to land-use changes and illegal trade for food and traditional medicine. Using distribution records and maximum entropy modeling, we predicted the potential distribution of the Chinese pangolin across Nepal. Most suitable potential habitats of the Chinese pangolin occurred in forest areas of the mid-hill region in central and eastern Nepal, followed by cultivated land. Almost all potential suitable habitats of the Chinese pangolin occurred outside of protected areas, and most of them were encroached upon by cultivated land, human settlements, and infrastructure developments. The results from this study provide baseline information on the potential suitable habitats of the Chinese pangolin in Nepal, which helps to develop site- and species-specific management plans and to identify priority areas to minimize the current threats to the pangolin and enhance the stewardship of species conservation.



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