scholarly journals Biogeography and conservation of Andean and Trans-Andean populations of Pyrrhura parakeets in Colombia: Modelling geographic distributions to identify independent conservation units

2012 ◽  
Vol 22 (4) ◽  
pp. 445-461 ◽  
Author(s):  
ESTEBAN BOTERO-DELGADILLO ◽  
CARLOS ANDRÉS PÁEZ ◽  
NICHOLAS BAYLY

SummaryThe criteria and categories of the IUCN red list can be applied to any taxonomic unit, including taxa below species level or non-formally described forms, but this is seldom practiced. Because conservation priorities largely focus on well-established taxa that deserve urgent action, cryptic species may be facing a critical situation. This could be the case for some Andean and trans-Andean populations of Pyrrhura parakeets in Colombia that have restricted and isolated geographic ranges, and whose conservation status has been overlooked because nominal species covering them are considered of “Least Concern”. As part of research into the biogeographic history and biogeographic patterns of the genus Pyrrhura, we used MaxEnt modelling to make a first approach to the geographic distribution and conservation status of these populations, and to determine if they could be considered independent conservation units. As with other members of Pyrrhura, we found that their climatic niche was restricted to humid regions of the Andes and the Andean foothills, resulting in isolated and discontinuous distributions associated with the Tropical humid forest Zonobiome. Comparing our estimates of area of occupancy with the established thresholds for IUCN criterion B2, the four subspecies studied could be considered threatened. The small geographic ranges, apparent vulnerability to forest fragmentation compared with other parrots, and extensive habitat loss experienced by the Andean and trans-Andean subspecies of P. melanura and P. picta allow us to conclude that they are valid conservation units. Although further research on these taxa is necessary, our results imply that they must be included as target populations in local and national policies for management plans and decision making, and urgent actions are needed for the subspecies of P. picta such as P. p. subandina and P. p. caeruleiceps.

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.


2011 ◽  
Vol 2011 ◽  
pp. 1-14 ◽  
Author(s):  
Beth A. Polidoro ◽  
Cristiane T. Elfes ◽  
Jonnell C. Sanciangco ◽  
Helen Pippard ◽  
Kent E. Carpenter

Given the economic and cultural dependence on the marine environment in Oceania and a rapidly expanding human population, many marine species populations are in decline and may be vulnerable to extinction from a number of local and regional threats. IUCN Red List assessments, a widely used system for quantifying threats to species and assessing species extinction risk, have been completed for 1190 marine species in Oceania to date, including all known species of corals, mangroves, seagrasses, sea snakes, marine mammals, sea birds, sea turtles, sharks, and rays present in Oceania, plus all species in five important perciform fish groups. Many of the species in these groups are threatened by the modification or destruction of coastal habitats, overfishing from direct or indirect exploitation, pollution, and other ecological or environmental changes associated with climate change. Spatial analyses of threatened species highlight priority areas for both site- and species-specific conservation action. Although increased knowledge and use of newly available IUCN Red List assessments for marine species can greatly improve conservation priorities for marine species in Oceania, many important fish groups are still in urgent need of assessment.


Oryx ◽  
2006 ◽  
Vol 40 (2) ◽  
pp. 183-188 ◽  
Author(s):  
Walter J. Reisinger ◽  
Devi M. Stuart-Fox ◽  
Barend F.N. Erasmus

We quantified habitat associations and evaluated the conservation status of a recently identified, undescribed species of dwarf chameleon, Bradypodion sp. nov. Dhlinza, endemic to scarp forest remnants in KwaZulu-Natal Province, South Africa. At the microhabitat scale the Dhlinza dwarf chameleon was found more often in forest gaps and near paths than highly disturbed edges or forest interior. Chameleon presence was not explained by forest physiognomic variables such as vine cover, shrub and tree density, or canopy cover. Presence near gaps may be better explained by the combined effects of the thermal microenvironment and food availability. The species is moderately common where it occurs, with estimated densities of 4.7, 8.7 and 29.7 individuals per ha within forest interior, edges and gaps respectively. At the landscape scale, the chameleon occurs only in three remnant forests: the Dhlinza, Entumeni and Ongoye Forests. The species' extent of occurrence was estimated to be 88 km2 and its area of occupancy 49 km2. Based on the small area of remaining suitable habitat, this species meets the requirements for categorization as Endangered according to IUCN Red List criteria.


2020 ◽  
Vol 21 (8) ◽  
Author(s):  
Iyan Robiansyah ◽  
Wita Wardani

Abstract. Robiansyah I, Wardani W. 2020. Increasing accuracy: The advantage of using open access species occurrence database in the Red List assessment. Biodiversitas 21: 3658-3664. IUCN Red List is the most widely used instrument to assess and advise the extinction risk of a species. One of the criteria used in IUCN Red List is geographical range of the species assessed (criterion B) in the form of extent of occurrence (EOO) and/or area of occupancy (AOO). While this criterion is presumed to be the easiest to be completed as it is based mainly on species occurrence data, there are some assessments that failed to maximize freely available databases. Here, we reassessed the conservation status of Cibotium arachnoideum, a tree fern distributed in Sumatra and Borneo. This species was previously assessed by Praptosuwiryo (2020, Biodiversitas 21 (4): 1379-1384) which classified the species as Endangered (EN) under criteria B2ab(i,ii,iii); C2a(ii). Using additional data from herbarium specimens recorded in the Global Biodiversity Information Facility (GBIF) website and from peer-reviewed scientific papers, in the present paper we show that C. arachnoideum has a larger extent of occurrence (EOO) and area of occupancy (AOO), more locations and different conservation status compared to those in Praptosuwiryo (2020). Our results are supported by the predicted suitable habitat map of C. arachnoideum produced by MaxEnt modelling method. Based on our assessment, we propose the category of Vulnerable (VU) C2a(i) as the global conservation status for C. arachnoideum. Our study implies the advantage of using open access databases to increase the accuracy of extinction risk assessment under the IUCN Red List criteria in regions like Indonesia, where adequate taxonomical information is not always readily available.


2021 ◽  
Vol 28 (3A) ◽  
pp. 1-110
Author(s):  
Nikolay A. Poyarkov ◽  
Tan Van Nguyen ◽  
Evgeniy S. Popov ◽  
Peter Geissler ◽  
Parinya Pawangkhanant ◽  
...  

The Indochinese Peninsula is recognized as one of the key global biodiversity hotspots. The amphibian fauna of Indochina (including Vietnam, Laos, Cambodia and Thailand) is one of the richest in the world. About 60% of the known species were described within the last 20 years. We review the literature and our data to assess all recent discoveries and taxonomic changes and compile the first annotated checklist of the amphibian fauna of Indochina since the middle of the 20th century, including updated faunal lists for Vietnam and Thailand. Amphibian checklists for Laos and Cambodia are published for the first time. For each species we provide the following information: scientific name; recommended common name in English; information on type specimens; type locality; data on its distribution within Indochina and beyond; IUCN conservation status; taxonomic comment and the most important references. We review the distribution of each species across the 23 biogeographic subregions of Indochina, estimate the similarity among the regional faunas and evaluate their species richness and endemism. In total we record 423 amphibian species belonging to three orders, 11 families and 71 genera; 199 species (47%) are endemic to Indochina. Comprising 270 known species, the amphibian fauna of Vietnam is the richest (98 endemics, 36.3%), followed by Thailand with 194 species (29 endemics, 14.9%), Laos with 121 species (13 endemics, 10.7%), and Cambodia with 72 species (6 endemics, 8.3%). A cluster analysis of faunal similarity between the subregions shows two major assemblages, divided by the Isthmus of Kra. Within the northern mainland portion of Indochina three clusters can be distinguished: (1) northeastern and northwestern uplands of Vietnam and northern Laos; (2) Northern, Central, and Southern Annamites, the Bolaven Plateau, and central-south Vietnam lowlands; (3) western Indochinese subregions. We identify the Northeast and Northwest Uplands of Vietnam, the Northern, Central and Southern Annamites, the Cardamom Mountains, the mountains of Northeast Thailand, Northern Tenasserim and southern Peninsular Thailand as nine major centers of diversity and endemism of Indochinese amphibians. The analysis of amphibian distribution patterns across Indochina suggests the presence of 14 chorotypes grouped in five major range types. Our results underline the role of Indochina as a key area for amphibian diversity and conservation. Among 423 species of Indochinese amphibians, 152 species (35.9%) were considered as data deficient (DD) or were not evaluated (NE) according to the IUCN Red List criteria; while 76 species (18.0%) were considered vulnerable (VU), endangered (EN) or critically endangered (CR), 20 species (4.7%) were considered to be near threatened (NT), and 175 species (41.4%) to be of the least concern (LC). Our study thus has implications for further conservation efforts on regional and global levels, as well as for understanding the biogeographic patterns of amphibian richness and endemism in Asia.


Oryx ◽  
2019 ◽  
pp. 1-10 ◽  
Author(s):  
P. J. Stephenson ◽  
Voahangy Soarimalala ◽  
Steven M. Goodman ◽  
Martin E. Nicoll ◽  
Vonjy Andrianjakarivelo ◽  
...  

Abstract The mammal family Tenrecidae (Afrotheria: Afrosoricida) is endemic to Madagascar. Here we present the conservation priorities for the 31 species of tenrec that were assessed or reassessed in 2015–2016 for the IUCN Red List of Threatened Species. Six species (19.4%) were found to be threatened (4 Vulnerable, 2 Endangered) and one species was categorized as Data Deficient. The primary threat to tenrecs is habitat loss, mostly as a result of slash-and-burn agriculture, but some species are also threatened by hunting and incidental capture in fishing traps. In the longer term, climate change is expected to alter tenrec habitats and ranges. However, the lack of data for most tenrecs on population size, ecology and distribution, together with frequent changes in taxonomy (with many cryptic species being discovered based on genetic analyses) and the poorly understood impact of bushmeat hunting on spiny species (Tenrecinae), hinders conservation planning. Priority conservation actions are presented for Madagascar's tenrecs for the first time since 1990 and focus on conserving forest habitat (especially through improved management of protected areas) and filling essential knowledge gaps. Tenrec research, monitoring and conservation should be integrated into broader sustainable development objectives and programmes targeting higher profile species, such as lemurs, if we are to see an improvement in the conservation status of tenrecs in the near future.


Oryx ◽  
2017 ◽  
Vol 52 (2) ◽  
pp. 300-315 ◽  
Author(s):  
J. Antonio de la Torre ◽  
José F. González-Maya ◽  
Heliot Zarza ◽  
Gerardo Ceballos ◽  
Rodrigo A. Medellín

AbstractThe IUCN Red List is widely used to guide conservation policy and practice. However, in most cases the evaluation of a species using IUCN Red List criteria takes into account only the global status of the species. Although subpopulations may be assessed using the IUCN categories and criteria, this rarely occurs, either because it is difficult to identify subpopulations or because of the effort involved. Using the jaguar Panthera onca as a model we illustrate that wide-ranging species that are assigned a particular category of threat based on the IUCN Red List criteria may display considerable heterogeneity within individual taxa in terms of the level of risk they face. Using the information available on the conservation status of the species, we evaluated the jaguar's current geographical range and its subpopulations. We identified the most threatened subpopulations, using the extent of occurrence, area of occupancy, population size and the level of threat to each subpopulation. The main outcome of this analysis was that although a large subpopulation persists in Amazonia, virtually all others are threatened because of their small size, isolation, deficient protection and the high human population density. Based on this approach, future conservation efforts can be prioritized for the most threatened subpopulations. Based on our findings we recommend that for future Red List assessments assessors consider the value of undertaking assessments at the subpopulation level. For the jaguar, sub-global assessments should be included on the Red List as a matter of urgency.


Oryx ◽  
2006 ◽  
Vol 40 (4) ◽  
pp. 464-467 ◽  
Author(s):  
Michael M. Driessen ◽  
Stephen A. Mallick ◽  
Andrew Lee ◽  
Shaun Thurstans

Extant representatives of the ancient crustacean family Anaspididae are restricted to the island State of Tasmania, Australia. Allanaspides hickmani and Allanaspides helonomus were first described in the early 1970s from surface pools in buttongrass moorland in two adjacent watersheds in south-west Tasmania. Both of these catchments have since been inundated for hydroelectric power generation (Lake Gordon and Serpentine Impoundments). Surveys indicate that both species persist in a small number of highly fragmented populations on the margins of the two impoundments. A. hickmani and A. helonomus have extant Areas of Occupancy of c. 21 and 54 km2, respectively. We estimate that inundation resulted in the loss of 85–94% of the original range of A. hickmani and c. 78% of the original range of A. helonomus. Under IUCN Red List guidelines and National threatened species legislation A. hickmani but not A. helonomus may qualify for listing as Vulnerable (Area of Occupancy <20 km2). At the present time only A. hickmani is listed as Rare under Tasmanian (State) threatened species legislation but A. helonomus merits the same listing under State legislation. Global warming appears to pose the most significant potential threat to Allanaspides species.


Oryx ◽  
2011 ◽  
Vol 45 (3) ◽  
pp. 439-443 ◽  
Author(s):  
Rodrigo C. Printes ◽  
Anthony B. Rylands ◽  
Júlio César Bicca-Marques

AbstractThe blond titi monkey Callicebus barbarabrownae lives in forest fragments in the caatinga (tropical thorn scrub and forest) of north-east Brazil. In 2004–2005 we carried out five surveys to determine its current distribution and conservation status; surveying forest fragments, interviewing local people, and recording vegetation types and patterns of land use. The blond titi monkey occurs mainly in Dense Arboreal Caatinga and Highland Coastal Rainforest in the state of Bahia, at elevations of 241–908 m. Its range extends over 291,438 km2, with an area of occupancy of 2,636 km2. Estimated minimum population was 260 individuals. It was not recorded in any protected area. Cattle ranching favours the persistence of forest fragments for this species, whereas agriculture, subsistence or commercial, does not. Our findings supported the IUCN Red List assessment of Critically Endangered for this species.


2018 ◽  
Vol 10 (8) ◽  
pp. 12056
Author(s):  
Kersley Bruno Pynee ◽  
David Harold Lorence ◽  
Poojanraj Khurun

Aerva congesta Balf.f. ex Baker (Amaranthaceae), an endemic of Mascarene Islands (Mauritius and Rodrigues) is assessed for its conservation status. Considering its local extinction in Rodrigues and very small population in Mauritius, in Round Island and at Gris Gris, south of Mauritius its area of occupancy (AOO) is estimated at 8km².  Due to its small AOO and threats by increasing native vegetation and alien species, A. congesta is evaluated as Critically Endangered following the latest IUCN Red List criteria.  The species needs an urgent well-defined restoration program and ecological studies to prevent its extinction.  


Sign in / Sign up

Export Citation Format

Share Document