scholarly journals Mapping local and regional distribution of Lygophis paucidens Hoge, 1952 (Serpentes, Dipsadidae), an elusive snake from the sandy savannas of Brazil and Paraguay

Check List ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 75-81
Author(s):  
Filipe Alexandre Cabreirinha Serrano ◽  
João Paulo dos Santos Vieira-Alencar ◽  
Juan Camilo Diaz-Ricaurte ◽  
Cristiano de Campos Nogueira

Lygophis paucidens Hoge, 1952 is a rare Neotropical snake, previously mapped using only a few individuals in five localities. Herein we update and discuss the distribution and conservation status of L. paucidens within major Neotropical ecoregions, providing previously unavailable data on distribution and habitat use. We compiled and mapped point locality records from literature and museum specimens, complemented by field studies in three localities. We used those records to map the species Extent of Occurrence (EOO) and Area of Occupancy (AOO), two range-related metrics of central relevance for conservation. We recovered 52 records from 46 vouchered specimens and six field records, distributed in 35 individual point localities, all within the diagonal of open vegetation in South America, with most records in cerrado savannas with sandy soils. Lygophis paucidens is likely a psammophilous species, which might explain its occurrence in savanna enclaves in forested ecoregions and its potentially discontinuous distribution. This knowledge is, therefore, useful in aiding future conservation assessments.

Hacquetia ◽  
2020 ◽  
Vol 19 (2) ◽  
pp. 307-315
Author(s):  
Ümit Subaşı ◽  
Fatoş Şekerciler ◽  
Mecit Vural

AbstractLotus sanguineus is one of the endemic taxa from Mediterranean Region of Turkey. It has hitherto been known from type locality and was assessed under VU and EN categories despite the lack of information on the population size, number of location and habitat quality. This study aims to determine the global conservation status and conservation strategies of the narrow endemic species. We collected all available data and evaluated them with the field studies. We reported the sizes of populations, altitude, coordinates, habitat types and the threats it faces for each locality. GeoCAT analyses at global levels indicate the extent of occurrence 19.965 km2 and area of occupancy 9 km2 and there could be an inferred decline due to habitat loss and fragmentation of the original population, suggesting this species might be classified as Critically Endangered, based on criterium B1ab (i, ii, iii) + 2ab (i, ii, iii) in the Red List categorization. Conservation priorities include life history and ecology studies, in-situ conservation, population monitoring and ex-situ conservation to prevent the destruction of the existing gene pool.


2020 ◽  
Vol 47 (2) ◽  
pp. 146
Author(s):  
Graeme R. Gillespie ◽  
Yusuke Fukuda ◽  
Peter McDonald

Abstract ContextSpecies conservation assessments require information on distribution, habitat requirements and population demography and trends. Uncertain conservation assessments limit effective planning and may lead to poor management decisions. Top-order predators generally receive considerable attention from ecologists and conservation biologists, with the notable exception of large pythons and boas. They are typically elusive and have low population densities, posing challenges for ecological research and monitoring. Ecological and demographic data are lacking for most large snake species and are generally inadequate to properly assess conservation status or to evaluate their broader ecological roles. The Oenpelli python (Simalia oenpelliensis) is Australia’s second-longest snake species, but remains one of the least-known of the world’s pythons. AimsWe sought to use non-systematically collected data from multiple sources to evaluate Oenpelli python population trends and habitat associations, and to assess its conservation status. MethodsWe identified a priori biases in data and evaluated their influences on environmental models and temporal variability in reporting patterns. We then used these findings to assess the conservation status of this species, identify knowledge gaps, and refine future survey and monitoring methods. Key resultsOenpelli python records were strongly associated with monsoon rainforest, sandstone outcrops and perennial streams, irrespective of detection biases. Total area of occupancy was estimated to be 19252km2. Detection patterns were strongly seasonal and associated with periods of low rainfall and low moonlight, informing better-targeted survey and monitoring methods with improved sensitivity. ConclusionsOenpelli pythons have a highly fragmented distribution owing to their strong association with monsoon rainforest. This habitat is likely to provide more food resources and refuge from high temperatures than are the surrounding savanna woodlands. Detection probability should improve by surveying Oenpelli pythons in September on moonless nights and following periods of high rainfall. Taking a precautionary approach, the Oenpelli python qualifies as Vulnerable under IUCN criteria, supporting its current Red List and Northern Territory Government status. ImplicationsNon-systematically collected data on poorly known species can be used to improve conservation assessments where there may otherwise be high uncertainty. The present study also highlighted the paucity of ecological knowledge of large iconic snake species globally.


2017 ◽  
Vol 28 (4) ◽  
pp. 653-661 ◽  
Author(s):  
KAI GEDEON ◽  
DENNIS RÖDDER ◽  
CHEMERE ZEWDIE ◽  
TILL TÖPFER

SummaryThe occurrence of the Black-fronted Francolin Pternistis atrifrons is restricted to a tiny area in southern Ethiopia. Based on field studies from 2012 to 2014, we modelled the range and estimated the population size of the species in order to evaluate its current conservation status. Annual mean temperature (relatively low) and precipitation (relatively high) proved to be key factors for the probability of its occurrence. The modelled range is 1,286 km2 (“extent of occurrence” according to the IUCN Red List criteria). However, only about one third of the modelled range is actually populated by the Black-fronted Francolin. This area, around 385 km2, corresponds to the IUCN’s “area of occupancy”. The total population size is estimated at 1,100 to 2,100 mature individuals. Thus, we conclude that the species should be classified as Endangered, criteria: A2c+B1ab(i,iii,v) + B2ab(i,iii,v); population trend: decreasing. This means that the Black-fronted Francolin is one of Africa’s most endangered galliforms. Major threats are range and habitat losses due to agricultural expansion, grazing pressure, commercial firewood and timber exploitation, and hunting. Furthermore, expected climate changes in south-east Ethiopia (higher temperatures, less precipitation) could further exacerbate these threats. We propose urgent conservation actions, including the extension of the currently projected Borana National Park.


2020 ◽  
Vol 96 (2) ◽  
pp. 411-429 ◽  
Author(s):  
Manfredo Alejandro Turcios-Casco ◽  
Hefer Daniel Ávila-Palma ◽  
Richard К. LaVal ◽  
Richard D. Stevens ◽  
Eduardo Javier Ordoñez-Trejo ◽  
...  

During the last century, survey efforts for mammals in Honduras have been few and most distributional and conservation assessments of bats have been based on historical records. Taxonomy of many records has changed. Moreover, a number of supposed Honduran occurrences are based on records from bordering countries without confirmation by a Honduran voucher. Therefore, the list of bats of Honduras lacks precision. Here, we update the number of species in the country, including taxonomic changes not reflected in recent works and new records based on museum specimens. The known number of species for Honduras is 113 with seven expected (Cormura brevirostris, Lampronycteris brachyotis, Mesophylla macconnelli, Molossus coibensis, M. pretiosus, Thyroptera discifera and Trinycteris nicefori), based on records in adjoining countries. We provide a new record for Honduras of Natalus lanatus. We confirm the presence of Cynomops greenhalli and Diaemus youngii and clarify the taxonomic status of Artibeus intermedius, Chiroderma gorgasi, Eumops ferox, Gardnerycteris keenani, Lasiurus frantzii, Myotis pilosatibialis, Molossus and Pteronotus species, and Tonatia bakeri. We recommend a reassessment of the conservation status of the bats of Honduras considering recent changes and that a number of species (e.g. Choeronycteris mexicana) have not been observed since their reports in historical records. This requires an update of the taxonomic identification keys for Honduras. The updated checklist below demonstrates the high biodiversity of Honduran bats but is also an example of how poorly many groups have been studied since they were first recorded in the country.


Author(s):  
Titien Ngatinem Praptosuwiryo

Abstract. Praptosuwiryo TN. 2020. Assessing the conservation status of tree fern Cibotium arachnoideum (C.Chr.) Holttum. Biodiversitas 21: 1379-1384. Cibotium arachnoideum (C.Chr.) Holttum (Cibotiaceae), is a large terrestrial fern with an upright or prostrate rhizome having densely shining reddish-brown of rigid hairs and one or two pairs of sori with two indusia forming a small cup on each lamina-segment. This tree fern is a rare species and strictly distributed in the Malesian region. The study aims to assess the conservation status of C. arachnoideum by using the 2012 IUCN Red List Catagories and Criteria (version 3.1.). Population size was estimated and observed both based on specimens deposited at the Herbarium Bogoriense (BO) and field studies in Sumatra. The area of occupancy (AOO) of this species is 44 km2. Cibotium arachnoideum is occurred in severely fragmented locations in the West Malesian region, in 2 locations, viz. Sumatra and Borneo. Sumatra has only two subpopulations, and Borneo has nine subpopulations. The number of mature individuals was only found 372 in one location of North Sumatra and 19 individuals in one location of Bengkulu. Therefore, C. arachnoideum is proposed as an endangered species, En: B2ab (i,ii,iii) + C2a (ii).


Oryx ◽  
2020 ◽  
pp. 1-4
Author(s):  
Germán Garrote ◽  
Beyker Castañeda ◽  
Jose Manuel Escobar ◽  
Laura Pérez ◽  
Brayan Marín ◽  
...  

Abstract The giant otter Pteronura brasiliensis, categorized as Endangered on the IUCN Red List, was once widely distributed throughout South America. By the middle of the 20th century the giant otter had become locally extinct along the main rivers of the Orinoco basin. Although some populations seem to have recovered, the paucity of information available does not permit a full evaluation of the species' conservation status. The objective of this study was to estimate the abundance and density of the giant otter population along the Orinoco river in the municipality of Puerto Carreño, Vichada, Colombia, where there is important commercial and recreational fishing. Thirty-nine linear km were surveyed, repeatedly, with a total of 315 km of surveys. Population size was estimated by direct counts of individuals. All individuals detected were photographed and identified individually from their throat pelage patterns. In total, 30 otters were identified, giving a minimum density of 0.77 individuals per km, one of the highest reported for the species in Colombia. Given the high density in this well-developed area, our results highlight the importance of this population for the conservation of the species.


Oryx ◽  
2020 ◽  
pp. 1-6
Author(s):  
María M. Torres-Martínez ◽  
Héctor E. Ramírez-Chaves ◽  
Elkin A. Noguera-Urbano ◽  
Fernando C. Passos

Abstract The brown hairy dwarf porcupine Coendou vestitus is a poorly studied Andean species endemic to Colombia. Its current Red List category is contradictory: globally it is categorized as Data Deficient but in Colombia it is categorized as Vulnerable. This contradiction has limited the implementation of conservation programmes. We evaluate the level of rarity of the species and provide consolidated information for a new assessment of its Red List status. We reviewed literature, photographs, and voucher specimens in natural history collections. Using the confirmed records, we estimated the extent of occurrence (EOO) based on the minimum convex polygon and the area of occupancy (AOO) summing the area of grid squares occupied by the species. We found that C. vestitus is very rare, with a small range, low estimated population density, occurrence in only one habitat type and small body size. The species has an EOO of 3,323 km2 and an AOO of 24 km2, based on six confirmed localities, all on the western slopes of the Eastern Cordillera, in the central Andean region of Colombia. Based on the species' rarity, restricted distribution, and threats to its natural habitat, we recommend its categorization as Endangered on the IUCN Red List. This will help delineate research and conservation efforts for this porcupine, which has a highly restricted range and inhabits the threatened Andean forest.


2006 ◽  
Vol 78 (5) ◽  
pp. 1081-1090 ◽  
Author(s):  
Werner Kördel ◽  
Michael Klein

Herein, we describe how pesticide leaching is assessed in Europe in order to fulfill EU Directive 91/414. The assessment schemes were developed to protect groundwater from unacceptable effects caused by pesticide use. They presently focus on chromatographic flow processes, which are dominant in sandy soils. Nevertheless, important regions in Europe are characterized by structured soils where transport through macropores is most relevant.Comparison of parallel field studies with isoproturon performed in sandy and silty soils showed that maximum concentration in the structured soil at a soil depth of 1 m may exceed respective concentrations in sandy soils by a factor of 60. Similar results were obtained by lysimeter studies using silty soil cores with maximum concentration of 40 μg/l at the soil bottom. These results demonstrate that preferential flow is more the rule than the exception in well-structured fine-textured soils, and pesticide losses via macropore flow may exceed losses via matrix transport considerably. All present information available for macropore flow suggest the need for greater regional assessments. Other recommendations include analysis of the influence of different soil management practices on the formation of macropores.


1991 ◽  
Vol 1 (2) ◽  
pp. 153-169 ◽  
Author(s):  
Philip Desenne ◽  
Stuart D. Strahl

SummaryAn assessment of trade in parrots throughout Venezuela, 1988–1989, reveals alarmingly high internal and international levels. The national trade has main outlets in major cities, but is now compounded by the use of feathers for Indian artifacts sold to tourists. International trade involves illegal export chiefly from the Orinoco Delta, the majority of such birds (65,000–75,000) destined for Guyana. The large macaws suffer badly from both types of trade, but owing to its restricted range the endemic Amazona barbadensis is perhaps the most critically threatened species. Other species are assessed and, along with key sites, identified in priority order for remedial action, which should include more detailed field studies, rigorous trade data analysis, exchange of trade data with major neighbours, census and monitoring technique improvements, educational campaigns, and strict breeding facility control.


2015 ◽  
Vol 25 (4) ◽  
pp. 451-465 ◽  
Author(s):  
ESTEBAN BOTERO-DELGADILLO ◽  
NICHOLAS BAYLY ◽  
CAMILA GÓMEZ ◽  
PAULO C. PULGARÍN-R. ◽  
CARLOS ANDRÉS PÁEZ

SummaryThe Santa Marta Foliage-gleaner Automolus rufipectus is one of 19 endemic bird species found in the Sierra Nevada de Santa Marta (SNSM) in northern Colombia but until recently it was considered a sub-species of the Ruddy Foliage-gleaner Automolus rubiginosus. Consequently, published information on its distribution and ecology is lacking, and while it is classified as near- threatened, this designation was based on limited quantitative data. To improve our knowledge of the Santa Marta Foliage-gleaner’s geographical distribution, elevation range, population density, habitat use and conservation status, we analysed both historical and recent site locality records and carried out variable distance transects within forested habitats and shade coffee plantations. We modelled the environmental niche of the species and subsequently estimated its extent of occurrence and area of occupancy, as well as population size. Our results consistently showed that the distribution of the Santa Marta Foliage-gleaner is more restricted than previously considered, both geographically and by elevation (we redefine elevation range as 600–1,875 m). This suggests that the species is more at risk of habitat transformation and combined with our estimates of population size (< 10,000 individuals), it is likely that the species will be uplisted to a higher threat category. More positively, and contrary to published accounts, we found that approximately 40% of the species’ range lies within protected areas. Nevertheless, we recommend the implementation of strategies to maintain forest cover on the western flank of the SNSM and further research to better define the species’ habitat needs and population dynamics.


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