scholarly journals Primates of Serranía de las Minas (Upper Magdalena Valley, Colombia)

2014 ◽  
Vol 1 (2) ◽  
pp. 17-20
Author(s):  
Eduardo Gallo-Cajiao ◽  
Carlos Julián Idrobo
Keyword(s):  
Habitat Loss ◽  
Forest Cover ◽  
Mountainous Region ◽  
Isolated Populations ◽  
Hunting Pressure ◽  
Colombian Andes ◽  
Risk Of Extinction ◽  
Mountain System

Primate populations have declined and disappeared from many localities of the Colombian Andes as a result of habitat loss and hunting pressure. The original forest cover of this mountainous region has been cleared by 70%, even though there has been a recent recovery of the area. Additionally, hunting practices have extirpated populations from otherwise suitable areas. These threats have resulted in smaller and isolated populations, with a higher risk of extinction, scattered across this mountain system.

scholarly journals Which is worse for the red-billed curassow: habitat loss or hunting pressure?

Oryx ◽  
2020 ◽  
pp. 1-9
Author(s):  
Elaine Rios ◽  
Philip J. K. McGowan ◽  
Nigel J. Collar ◽  
Maíra Benchimol ◽  
Gustavo R. Canale ◽  
...  
Keyword(s):  
Habitat Loss ◽  
Habitat Quality ◽  
Forest Cover ◽  
Explanatory Power ◽  
Forest Patches ◽  
Hunting Pressure ◽  
North East ◽  
Forest Remnants ◽  
The Status ◽  
Patch Density

Abstract Large ground-dwelling Neotropical gamebirds are highly threatened by habitat loss and hunting, but conservationists rarely attempt to distinguish between these two threats in the management of populations. We used three different types of species records to determine the status (i.e. persistence level) of the Endangered red-billed curassow Crax blumenbachii in 14 forest remnants in north-east Brazil, as either persistent, precarious or extirpated. We related these persistence levels to variables measured in a 2-km buffer radius, including variables associated with habitat quality (proportion of forest cover, length of rivers, patch density, distance from rivers) and hunting pressure (proportion of cacao agroforests and farmlands, length of roads, total area occupied by settlements, distance from roads and from settlements). Curassows were more persistent in forest patches located (1) more distant from settlements, (2) in landscapes with few settlements, (3) in landscapes with a high incidence of roads, (4) in a mosaic with a high proportion of forest, shaded cacao agroforest and farmland, and (5) more distant from other forest patches. Hunting pressure potentially exerts more influence on persistence than habitat quality: (1) hunting pressure submodels had a higher explanatory power than habitat quality submodels, (2) final models comprised four hunting pressure variables but only two habitat quality variables, and (3) hunting pressure variables appeared in all models whereas habitat quality variables appeared in only one final model. If hunting pressure is driving declines in curassows, regions with low human presence and a high proportion of forest cover are recommended for establishing new reserves.

scholarly journals LAND COVER DYNAMICS AND LANDSCAPE STRUCTURE IN THE AREA SURROUNDING WATER RESERVOIRS, MOUNTAINOUS REGION OF RIO DE JANEIRO

FLORESTA ◽  
2020 ◽  
Vol 50 (4) ◽  
pp. 1808
Author(s):  
Lucas De Siqueira Cardinelli ◽  
José Marinaldo Gleriani ◽  
Sebastião Venâncio Martins
Keyword(s):  
Land Cover ◽  
Landscape Structure ◽  
Rio De Janeiro ◽  
Forest Cover ◽  
Water Area ◽  
Mountainous Region ◽  
Water Reservoirs ◽  
Landsat Images ◽  
Surrounding Water ◽  
Land Cover Dynamics

The aim of this study is to evaluate land cover dynamics and landscape structure in the area surrounding two water reservoirs built-in 2009 for energy production, in the mountainous region of the State of Rio de Janeiro (Serra Fluminense). The analysis was developed through the interpretation of Landsat images from 2003, 2009, and 2013, considering the following land cover classes: early successional forest, mid successional forest, pasture, pasture with shrubs and trees, geological outcrop, urban area, and water area. We used thematic maps to determine landscape metrics of size and proximity in the reservoirs catchment area and the Permanent Preservation Area (PPA). At catchment level, pasture was predominant, a consequence of the extensive livestock production carried out in the whole watershed. During the evaluated period, the forest area remained consistent, however, fragmented in many small patches of mid successional forest. The average patch area of mid successional forest is three times the size of the early successional forest patches. For neither forest land cover classes, no significant variations through time in area or isolation were identified. On the PPA, an overall reduction of the forest cover was registered before the construction of the reservoir. However, from 2009 to 2013, after the enclosure of PPA areas, the forest cover increased 35% via assisted natural regeneration, suggesting a high potential for cost-effective restoration in the region.

scholarly journals Multi-taxa ecological responses to habitat loss and fragmentation in western Amazonia as revealed by RAPELD biodiversity surveys

2021 ◽  
Vol 51 (3) ◽  
pp. 234-243
Author(s):  
Gabriel M. MOULATLET ◽  
Emmanuel AMBRIZ ◽  
Jennifer GUEVARA ◽  
Karima G. LÓPEZ ◽  
Marina RODES-BLANCO ◽  
...  
Keyword(s):  
Species Composition ◽  
Habitat Loss ◽  
Forest Cover ◽  
Landscape Fragmentation ◽  
Dung Beetles ◽  
Landscape Configuration ◽  
Edge Density ◽  
Logistic Regression Models ◽  
Habitat Loss And Fragmentation ◽  
Taxonomic Groups

ABSTRACT Habitat loss and fragmentation caused by deforestation are important anthropogenic drivers of changes in biodiversity in the Amazon rainforest, and has reached its highest rate in recent decades. However, the magnitude and direction of the effects on species composition and distribution have yet to be fully understood. We evaluated the responses of four taxonomic groups − birds, amphibians, orchid bees, and dung beetles - to habitat loss and fragmentation at both species and assemblage level in the northern Ecuadorian Amazon. We sampled fifteen 250-m long plots in terra-firme forest remnants. We calculated one landscape fragmentation index (fragindex), which considers the proportion of continuous forest cover, edge density and isolation in the landscape, and nine landscape configuration metrics. Logistic regression models and multivariate regression trees were used to analyze species and assemblage responses. Our results revealed that over 80% of birds, amphibians or orchid-bee species, and 60% of dung beetles were negatively affected by habitat loss and fragmentation. Species composition of all taxonomic groups was significantly affected by differences in forest cover and connectivity. Less than 5% of all species were restricted to landscapes with fragindex values higher than 40%. Landscape metrics related to the shape and area of forest patches determined the magnitude and direction of the effect on species responses. Therefore, changes in the landscape configuration of Ecuadorian Amazonia should be minimized to diminish the effects of habitat loss and fragmentation on species occurrence and assemblage composition.

scholarly journals Realities of rarity: climatically and ecologically restricted, critically endangered Kandian Torrent Toads (Adenomus kandianus) breed en masse

2015 ◽  
Author(s):  
Madhava Meegaskumbura ◽  
Nayana Wijayathilaka ◽  
Nirodha Abayalath ◽  
Gayani Senevirathne
Keyword(s):  
Forest Cover ◽  
High Elevation ◽  
Habitat Associations ◽  
Egg Laying ◽  
Primary Forest ◽  
Isolated Populations ◽  
In The Wild ◽  
Suitable Habitats ◽  
Wide Geographic Distribution ◽  
Forest Habitats

Endemic to Sri Lanka, genus Adenomus contains two torrent-associated toad species whose ecology and natural history in the wild is virtually unknown. Adenomus kelaartii is relatively common, with a wide geographic distribution. Its sister species, A. kandianus, however, is restricted to two isolated populations in fast-disappearing montane and sub-montane forests. Formally declared extinct after not being recorded for over a century, a few A. kandianus were rediscovered in 2012 and redescribed as "the world's rarest toad". Here we report the results of a two-year study of the occurrence, habits and habitat associations of adult and larval A. kandianus using both general surveys and quadrat sampling. We show this to be a secretive species with a patchy distribution. Non-breeding female toads dwell in primary-forest habitats, but after heavy and sudden downpours they form large mating congregations in large streams. Amplexed pairs swim synchronously, enabling them to traverse fast currents. Egg-laying sites remain unknown, but the ability to dive and vocalize underwater, and characteristics of the eggs, suggest that they lay eggs in dark recesses of the stream. Tadpoles show microhabitat partitioning within the stream, with the greatest diversity of stages in slow-flowing rocky areas. The more robust stages possessing sucker discs exploit rocky-rapids, while metamorphic stages inhabit stream margins. We use DNA-barcoding to show the existence of two disparate toad populations. Distribution modeling with forest-cover layers added, predict a very small remaining area of suitable habitats. Conservation of this climatically and ecologically restricted species hinge largely on the preservation of high-elevation primary and riparian forests and unpolluted torrents.

scholarly journals Carnivores (Mammalia) from areas of Nearctic–Neotropical transition in Puebla, central Mexico: presence, distribution, and conservation

Check List ◽  
2016 ◽  
Vol 12 (1) ◽  
pp. 1833 ◽  
Author(s):  
Osvaldo Eric Ramírez-Bravo ◽  
Lorna Hernandez-Santin
Keyword(s):  
Habitat Loss ◽  
Conservation Status ◽  
The State ◽  
Lynx Rufus ◽  
Risk Category ◽  
Central Mexico ◽  
Leopardus Pardalis ◽  
Lethal Control ◽  
Hunting Pressure ◽  
Carnivore Species

The Nearctic and Neotropical realms converge in central Mexico, where many areas have not been adequately characterized. Our objective was to revise the distribution and conservation status of carnivores in the state of Puebla, central Mexico. Between September 2008 and January 2011, we conducted interviews and fieldwork on seven previously selected areas. We complemented our data with bibliographical research. We obtained 733 records for 21 species, representing 63% of the carnivores reported for Mexico. We expanded known ranges of three species: Ocelot (Leopardus pardalis), Bobcat (Lynx rufus), and Tropical Ringtail (Bassariscus sumichastrii). Fifty percent of the carnivore species we recorded in Puebla are considered under some risk category. We found that carnivores in our study area are vulnerable to hunting pressure, human-carnivore conflicts that result in lethal control practices, and extensive habitat loss.

scholarly journals Threatened primates in southern Vietnam

Oryx ◽  
1993 ◽  
Vol 27 (3) ◽  
pp. 146-154 ◽  
Author(s):  
Jonathan C. Eames ◽  
Craig R. Robson
Keyword(s):  
Protected Areas ◽  
Habitat Loss ◽  
Hunting Pressure ◽  
Southern Vietnam ◽  
The Status ◽  
Pygathrix Nemaeus ◽  
Rich Fauna ◽  
Human Encroachment

Vietnam's exceptionally rich fauna is threatened by habitat loss and hunting. Although a system of protected areas has recently been developed, many of the sites selected are subject to human encroachment, hunting pressure and other forms of exploitation. Other protected areas may be too small to hold viable populations of primates. Following faunal surveys of existing and proposed protected areas in Vietnam between 1988 and 1991, this paper documents the status of and identifies threats to three species of threatened primate: white-cheeked gibbon Hylobates leucogenys gabriellae, red-shanked douc langur Pygathrix nemaeus and blackshanked douc langur P. nigripes.

scholarly journals Conservation status of birds on Mindoro, Philippines

1992 ◽  
Vol 2 (4) ◽  
pp. 303-325 ◽  
Author(s):  
Guy C. L. Dutson ◽  
Tom D. Evans ◽  
Thomas M. Brooks ◽  
Desiderio C. Asane ◽  
Robert J. Timmins ◽  
...  
Keyword(s):  
Forest Cover ◽  
Conservation Status ◽  
Bird Species ◽  
Concerted Action ◽  
Medium Term ◽  
Lowland Forest ◽  
Risk Of Extinction ◽  
Forest Remnants ◽  
The Status

SummaryFour weeks of fieldwork in the forests of Mindoro, Philippines, in 1991 has elucidated the status of the six bird species endemic to the island. Of these, Ducula mindorensis and Otus mindorensis are high-altitude species with restricted ranges and in need of active conservation in the medium term. Three of the four lowland species, Gallicolumba platenae, Centropus steerü and Penelopides mindorensis are under immediate threat of extinction through forest clearance and fragmentation, while the fourth, Dicaeum retrocinctum, s i not under immediate threat but is certainly at risk of extinction in the long term. Whilst deforestation is an enormous problem across the entire Philippines, Mindoro is the smallest centre of endemism with the least forest cover after the Sulu Islands. Extinctions are believed inevitable within the next 10 years unless concerted action is urgently taken. The Halcon range must receive attention in order to conserve the montane species, but more urgent by far is the preservation of lowland forest remnants, concentrating on central-west Mindoro.

scholarly journals STRATIFIKASI PENGGUNAAN TAJUK OLEH YAKI (Macaca nigra) DI CAGAR ALAM TANGKOKO DUASUDARA SULAWESI UTARA

ZOOTEC ◽  
2015 ◽  
Vol 35 (1) ◽  
pp. 151
Author(s):  
Sylvia Laatung
Keyword(s):  
Habitat Loss ◽  
Nature Reserve ◽  
Nature Reserves ◽  
Local People ◽  
Habitat Condition ◽  
Hunting Pressure ◽  
North Sulawesi ◽  
Macaca Nigra ◽  
The Future

THE USE OF SHOOT STRATIFICATION OF YAKI (Macaca nigra) at DUASUDARA TANGKOKO NATURE RESERVE NORTH SULAWESI. The Sulawesi black macaques (Macaca nigra) habitat at the Tangkoko and Duasudara Nature Reserves in North Sulawesi Indonesia has been the focus of periodic assessment since the late 1970s.  Ongoing habitat loss and hunting remain the primary threats to the macaques in these adjacent reserves.  Surveyed on habitat condition (including vegetation stratum utilization profile) and the interaction between yaki and local people around the nature reserve were conducted over a four-month period. Methods used diagram for habitat profile and interviewed for interaction between yaki and local people. They used stratum A and B frequently (65.21%) in the forest and prefer big trees, with many branch to sleep. The spread of population depends on the availability of resources in the forest. Without increased efforts to reduce hunting pressure and habitat loss, the future of this population is in question. Keywords: The use of shoot stratification, macaca nigra, nature reserve

Assessing spatial dispersion, abundance, and conservation perspectives of Military Macaw Ara militaris populations in Mexico

2021 ◽  
pp. 1-19
Author(s):  
TIBERIO C. MONTERRUBIO-RICO ◽  
JUAN F. CHARRE-MEDELLÍN ◽  
YAMEL RUBIO-ROCHA ◽  
CARLOS BONILLA-RUZ ◽  
CLAUDIA CINTA-MAGALLÓN ◽  
...  
Keyword(s):  
Habitat Restoration ◽  
Forest Cover ◽  
Climatic Conditions ◽  
Conservation Strategies ◽  
Primary Forest ◽  
Isolated Populations ◽  
Extent Of Occurrence ◽  
Area Of Occupancy ◽  
Conservation Organizations ◽  
Conservation Corridors

Summary The preservation of Military Macaw Ara militaris in Mexico required the implementation of a nationwide assessment evaluating its vulnerability using IUCN criteria. With the combined effort of several institutions, the abundance, location, dispersion, habitat availability, and climatic conditions of areas occupied by the species were determined. Although the species’ extent of occurrence is extensive (263,919 km2) only 29% of this constitutes area of occupancy. Published estimates indicate a series of isolated populations containing from four macaws to 215. Macaws occurred in 35 populations in four regions of 16 states containing an estimated 1,563–3,263 macaws; lower than required for long-term viability. Within regions, neighbouring populations were separated by an average of 68 km. The extent of occurrence is heterogeneous, and macaws inhabit areas that differ in elevation, precipitation, temperature, and forest cover. Higher local abundances occur in landscapes where annual precipitation is ≥1,100 mm, and primary forest availability ≥1,800 km2. Although the existence of undetected macaw groups in Mexico is possible, these are likely to contain only small numbers of individuals, as most detected areas with macaws contain less than 40 individuals, and larger concentrations are more likely to be noticed due to their conspicuous behaviour. The species is threatened primarily by its low overall abundance, fragmented distribution, and forest loss around populations with the highest abundance. With the information generated, it is possible to design and implement specific management and conservation strategies at different geographic scales for the recovery and maintenance of the species in Mexico. It is necessary to strengthen collaborative programmes among conservation organizations, government agencies, and local communities in each region of the country to organize and finance community-based actions such as monitoring, habitat restoration, protection from poaching and the creation of a network of conservation corridors and macaw reserves focused on conservation.

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