scholarly journals KELIMPAHAN, ASOSIASI DAN ANCAMAN HABITAT Nepenthes bicalcarata Hook.f. DI CAGAR ALAM MANDOR, KALIMANTAN BARAT

2021 ◽  
Vol 24 (2) ◽  
pp. 66-75
Author(s):  
Sunardi Sunardi ◽  
Muhammad Mansur

Nepenthes bicalcarata Hook.f. merupakan jenis endemik dengan status konservasi rentan (vulnerable) menurut IUCN Red List. Penelitian ini bertujuan untuk mengetahui kelimpahan populasi, asosiasi, dan keterancaman habitat N. bicalcarata di Cagar Alam Mandor, Kalimantan Barat. Penelitian ini menggunakan metode analisis vegetasi, asosiasi jenis tumbuhan menggunakan indeks Ochiai, dan metode unsupervised classification pada citra Landsat 8 untuk mengetahui perubahan penutupan lahan. Penentuan lokasi pengambilan data dilakukan menggunakan metode purposive sampling. Pengambilan data vegetasi tumbuhan menggunakan sepuluh plot berukuran 10Í10 m. Hasil penelitian menunjukkan bahwa N. bicalcarata tersebar di delapan dari 14 kabupaten/kota di Kalimantan Barat. Populasi N. bicalcarata pada hutan kerangas berjumlah 300 individu/ha dan dan berasosiasi dengan jenis pohon Cratoxylum glaucum, Gymnostoma nobile, Antidesma coriaceum, Ficus variegata, dan Tristaniopsis merguensis. N. bicalcarata juga berasosiasi dengan Nepenthes lainnya, seperti N. ampullaria, N. rafflesiana, N. gracilis, N. mirabilis dan N. hookeriana. Perubahan penutupan lahan yang signifikan mengakibatkan peningkatan luasan areal terbuka dan pertambangan, sehingga mengancam habitat dan populasi N. bicalcarata. Kelimpahan N. bicalcarata di CA Mandor diprediksi akan semakin berkurang dengan adanya ancaman perubahan penutupan lahan tersebut. Berdasarkan kondisi tersebut, jenis ini perlu dilindungi dan dijaga kelestariannya di alam.

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 ◽  
2017 ◽  
Vol 53 (1) ◽  
pp. 159-164 ◽  
Author(s):  
Tariq Mahmood ◽  
Faraz Akrim ◽  
Nausheen Irshad ◽  
Riaz Hussain ◽  
Hira Fatima ◽  
...  

AbstractThe Endangered Indian pangolin Manis crassicaudata, a burrowing, armoured mammal, plays an important role in the food web by consuming insects and termites. In Pakistan the species’ range includes the 22,000 km2 Potohar Plateau, where it is under pressure from illegal hunting for its scales and requires conservation attention. We used a geographical information system to quantify the range of the Indian pangolin on the Plateau and to compare this with the range estimated in the IUCN Red List assessment of the species. We found that the species occupies c. 89% of the Plateau, in eight of the 10 protected areas, compared with the IUCN estimate of 71%, and we recorded the species at 40 locations on the Plateau outside the range predicted by the IUCN assessment. We collected data on the illegal capture and killing of the species, recording 412 individuals that had been killed at 48 locations between January 2011 and the end of April 2013. The highest number of killings was recorded in Chakwal District (n = 156, at 13 sites) followed by the Attock District (n = 149, at eight sites). Although the Indian pangolin's range on the Potohar Plateau is c. 18% larger than that estimated in the IUCN assessment, the species is under pressure from illegal killing and requires urgent conservation measures to save the small remaining population and avoid the extirpation of this vital insectivorous predator from the area.


Author(s):  
H. Reşit Akçakaya ◽  
Axel Hochkirch ◽  
Jason T. Bried ◽  
Roy H. A. van Grunsven ◽  
John P. Simaika ◽  
...  

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.


2021 ◽  
Vol 13 (11) ◽  
pp. 2233
Author(s):  
Rasa Janušaitė ◽  
Laurynas Jukna ◽  
Darius Jarmalavičius ◽  
Donatas Pupienis ◽  
Gintautas Žilinskas

Satellite remote sensing is a valuable tool for coastal management, enabling the possibility to repeatedly observe nearshore sandbars. However, a lack of methodological approaches for sandbar detection prevents the wider use of satellite data in sandbar studies. In this paper, a novel fully automated approach to extract nearshore sandbars in high–medium-resolution satellite imagery using a GIS-based algorithm is proposed. The method is composed of a multi-step workflow providing a wide range of data with morphological nearshore characteristics, which include nearshore local relief, extracted sandbars, their crests and shoreline. The proposed processing chain involves a combination of spectral indices, ISODATA unsupervised classification, multi-scale Relative Bathymetric Position Index (RBPI), criteria-based selection operations, spatial statistics and filtering. The algorithm has been tested with 145 dates of PlanetScope and RapidEye imagery using a case study of the complex multiple sandbar system on the Curonian Spit coast, Baltic Sea. The comparison of results against 4 years of in situ bathymetric surveys shows a strong agreement between measured and derived sandbar crest positions (R2 = 0.999 and 0.997) with an average RMSE of 5.8 and 7 m for PlanetScope and RapidEye sensors, respectively. The accuracy of the proposed approach implies its feasibility to study inter-annual and seasonal sandbar behaviour and short-term changes related to high-impact events. Algorithm-provided outputs enable the possibility to evaluate a range of sandbar characteristics such as distance from shoreline, length, width, count or shape at a relevant spatiotemporal scale. The design of the method determines its compatibility with most sandbar morphologies and suitability to other sandy nearshores. Tests of the described technique with Sentinel-2 MSI and Landsat-8 OLI data show that it can be applied to publicly available medium resolution satellite imagery of other sensors.


Author(s):  
M. García–Luis ◽  
M. Briones–Salas ◽  
M. C. Lavariega

We present a revised checklist of bat species occurring in the semi–urbanized region of the Central Valleys of Oaxaca, Mexico. The checklist is based on surveys using mist nets, recordings of echolocation calls, data from literature, and museum databases. Results show that the Central Valleys of Oaxaca have a species richness of 33 bat species belonging to 22 genera and five families. Species like the Mustached bat Pteronotus parnellii, the Western Red bat Lasiurus blossevillii and the Free–tailed bat Promops centralis were recorded after 32, 30 and 19 years respectively according to the records of the literature. We also recorded four species classified in some risk category according to either the Mexican government’s red list (NOM–059) or the IUCN red list. The recordings of the echolocation calls are the first from the region of Central Valleys of Oaxaca. Bat diversity in the Central Valleys of Oaxaca was underestimated and emphasizes the need for further research


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.


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