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 ◽  
...  

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.

Oryx ◽  
1993 ◽  
Vol 27 (3) ◽  
pp. 146-154 ◽  
Author(s):  
Jonathan C. Eames ◽  
Craig R. Robson

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.


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 ◽  
...  

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.


2014 ◽  
Vol 1 (2) ◽  
pp. 17-20
Author(s):  
Eduardo Gallo-Cajiao ◽  
Carlos Julián Idrobo

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.


GIS Business ◽  
2019 ◽  
Vol 14 (6) ◽  
pp. 341-348
Author(s):  
Dr. Mini Jain ◽  
Dr. Mini Jain

In India, higher education is a need of hour. The excellence of Higher Edification decides the production of skilled manpower to the nation. Indian education system significantly teaching has not been tested too economical to form youths of our country employable in line with the requirement of job market. Despite the rise in range of establishments at primary, secondary and tertiary level our young educated folks don't seem to be capable of being used and recovering job opportunities. Reason being they need not non-heritable such skills essential for demand of the duty market. The present study is aimed at analyzing the status of higher education institutions in terms of Infrastructure, various courses of the institute, quality Initiatives and skill development program offered by the Institutes, in the North-East India region, so as to see whether the Higher Educational Institutes of this region are in the process of gradually developing the skills of the students in attaining excellence. The paper also laid emphasis on the measures adopted by these institutes for quality improvement, and to find out their role in combating the adversity acclaimed in the region, since this region’s development is impeded by certain inherent difficulties However, this paper focuses attention on high quality education with special emphasis on higher education for forward linkages through value addition.


Author(s):  
Allen Buchanan

This chapter helps to confirm the explanatory power of the naturalistic theory of moral progress outlined in previous chapters by making two main points. First, it shows that the theory helps to explain how and why the modern human rights movement arose when it did. Second, it shows that the advances in inclusiveness achieved by the modern human rights movement depended upon the fortunate coincidence of a constellation of contingent cultural and economic conditions—and that it is therefore a dangerous mistake to assume that continued progress must occur, or even that the status quo will not substantially deteriorate. This chapter also helps to explain a disturbing period of regression (in terms of the recognition of equal basic status) that occurred between the success of British abolitionism and the founding of the modern human rights movement at the end of World War II.


2018 ◽  
Vol 38 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Sihem Hedjal ◽  
Derradji Zouini ◽  
Abdelwaheb Benamara

AbstractThe wetland complex of Guerbes-Sanhadja (north-eastern Algeria), has experienced in recent years a certain economic expansion, particularly agricultural, about 47% of the useful agricultural area marked by several varieties of crops ranging from market gardening to speculative crops, requiring large quantities of water for irrigation purposes, however the swampy areas are the main sources used for irrigation purposes in this practice. It is therefore necessary for this water to have physicochemical properties adapted to plants, in particular the absence of salinity. This study was done to evaluate the status of the swamps areas quality and its suitability for irrigated agriculture. To achieve this objective, water samples from ten swamps areas water were collected from Guerbes-Sanhadja in February and June of 2016. The water quality of these swamps was estimated from different water quality parameters such as pH and electrical conductivity (EC), the chemical parameters like Na+, K+, Ca2+, HCO3−, SO42−, Cl−, BOD5, NO3−, NO2−, NH4+ and PO43−. Based on the physico-chemical analyses, irrigation quality parameters like sodium absorption ratio (SAR), percent sodium (% Na), residual sodium carbonate (RSC), permeability index (PI), magnesium hazard (MH) were calculated. The results showed that the overall concentration of nitrate was very high. About 60 percent of the swampy areas had suitable water quality for chloride, and they had a concentration below the permissible limit for crop irrigation. From the Richards diagram, it is observed that most of the samples from the study area fall in the good to permissible classes for irrigation purpose.


2021 ◽  
Vol 51 (3) ◽  
pp. 234-243
Author(s):  
Gabriel M. MOULATLET ◽  
Emmanuel AMBRIZ ◽  
Jennifer GUEVARA ◽  
Karima G. LÓPEZ ◽  
Marina RODES-BLANCO ◽  
...  

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.


2021 ◽  
Vol 02 (04) ◽  
pp. 1-1
Author(s):  
Giorgos Mountrakis ◽  
◽  
Sheng Yang ◽  

While numerous studies have considered forest loss factors at local scales, there is a gap of comparative quantitative regional modeling at the U.S. national level. Here, we investigated statistical relationships between gross forest cover loss (GFCL) and numerous socioeconomic, biophysical and ownership variables between two decades, the 1990s and the 2000s. A spatial error model was employed to compensate for spatial autocorrelation effects. Models from the 2000s had stronger explanatory power than the 1990s models, especially in the Northeast and the South (R<sup>2</sup> of 0.89 and 0.87 respectively). The amount of forested areas in low slopes was a highly influential factor for high GFCL, followed by urban area cover and mill density. On the other hand, agricultural cover was negatively correlated with GFCL acting as a stabilizing factor in the South and Midwest regions. Our study offers an important insight in regional drivers of GFCL, drivers that should be further examined in the local context to gather better understanding of their contributions.


2017 ◽  
Author(s):  
Olga Makarieva ◽  
Nataliia Nesterova ◽  
Lyudmila Lebedeva ◽  
Sergey Sushansky

Abstract. As of 2017, 70 years have passed since the beginning of work at the Kolyma water-balance station (KWBS), a unique scientific research hydrological and permafrost catchment. The volume and duration (50 continuous years) of hydrometeorological standard and experimental data, characterizing the natural conditions and processes occurring in mountainous permafrost conditions, significantly exceeds any counterparts elsewhere in the world. The data are representative of the vast territory of the North-East of Russia. In 1997, the station was terminated, thereby leaving Russia without operating research watersheds in the permafrost zone. This paper describes the dataset containing the series of daily runoff from 10 watersheds with area from 0.27 to 21.3 km2, precipitation, meteorological observations, evaporation from soil and snow, snow surveys, soil thaw and freeze depths, and soil temperature for the period 1948–1997. It also highlights the main historical stages of the station's existence, its work and scientific significance, and outlines the prospects for its future, where the Kolyma water-balance station could be restored to the status of a scientific research watershed and become a valuable international center for hydrological research in permafrost. The data is available at https://doi.pangaea.de/10.1594/PANGAEA.881731.


1997 ◽  
Vol 13 (6) ◽  
pp. 857-866 ◽  
Author(s):  
Xue Ying Zhuang ◽  
Richard T. Gorlett

ABSTRACTHong Kong is on the northern margin of the Asian tropics. The original forest cover was cleared centuries ago but secondary forest has developed since 1945 at many sites protected from fire and cutting. There are also older forest patches maintained behind villages for reasons of ‘feng shui’, the Chinese system of geomancy. All plants >2 cm dbh were identified and measured in forty-four 400-m2 plots. Detrended correspondence analysis showed a floristic continuum, with the montane sites (>500 m) most distinct and some overlap between lowland post-1945 secondary forest and the feng shui woods. The 30–40 year-old secondary forest is dominated by Persea spp. Montane forest is similar but lacks several common lowland taxa of tropical genera and includes more subtropical taxa. The feng shui woods have the most complex structure and contain some tree species not found in other forest types. Their origin and history is obscure but we suggest that both planting and selective harvesting have had a role in their current species composition


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