scholarly journals The Endangered giant nuthatch Sitta magna: population size, habitat availability and the implications for its conservation in Thailand

Oryx ◽  
2021 ◽  
pp. 1-7
Author(s):  
Daphawan Khamcha ◽  
Rongrong Angkaew ◽  
Andrew J. Pierce ◽  
George A. Gale
Keyword(s):  
Basal Area ◽  
Dry Forest ◽  
Habitat Characteristics ◽  
Western China ◽  
Suitable Habitat ◽  
Thai Population ◽  
Point Count ◽  
Pinus Kesiya ◽  
Large Tree ◽  
Preferred Habitat

Abstract Available habitat and hence the global population of the Endangered giant nuthatch Sitta magna, restricted to lower montane habitats of south-western China, eastern Myanmar and northern Thailand, remains poorly quantified. Thailand is the only portion of the species’ range for which there is a population estimate. To obtain a more precise estimate of the Thai population and clarify the extent and characteristics of suitable habitat remaining, we conducted 335 point-count surveys at 67 points across eight localities during November 2019–February 2020. We estimated abundance and identified preferred habitat characteristics using N-mixture models, and created suitable habitat maps based on data from surveys and remote sensing. Our estimate for Thailand was 578 (95% CI 391–854) individuals based on a density of 3.7 (95% CI 2.5–5.5) individuals/km2 in 156 km2 of suitable habitat. The giant nuthatch prefers dry forest with a large amount of mature native or planted pine Pinus kesiya and with a large tree basal area and an open canopy. Our estimate of suitable habitat remaining was less than previously reported and thus the population has probably decreased, although most of this habitat is within protected areas. Habitats for the species in Thailand have a stronger level of protection than in Myanmar and China, although habitat in China remains unquantified. We recommend further research in Myanmar and China, which may hold the majority of available habitat for the giant nuthatch. For long-term management, detailed study of the association of the giant nuthatch with pine plantations is required.

Tree density, basal area and species diversity in a disturbed dry tropical forest of northern India: implications for conservation

2006 ◽  
Vol 33 (3) ◽  
pp. 256-262 ◽  
Author(s):  
R. SAGAR ◽  
J.S. SINGH
Keyword(s):  
Species Diversity ◽  
Tropical Forest ◽  
Basal Area ◽  
Tree Density ◽  
Dry Forest ◽  
Conservation Strategies ◽  
Stem Density ◽  
Dry Tropical Forest ◽  
Number Of Species ◽  
Northern India

Dry tropical forest communities are among the world's most threatened systems and urgent measures are required to protect and restore them in degraded landscapes. For planning conservation strategies, there is a need to determine the few essential measurable properties, such as number of species and basal area, that best describe the dry forest vegetation and its environment, and to document quantitative relationships among them. This paper examines the relationships between forest basal area and diversity components (number of species and evenness) for a disturbed dry tropical forest of northern India. Data were collected from five sites located in the Vindhyan dry tropical forest of India, selected on the basis of satellite images and field observations to represent the entire range of conditions in terms of canopy cover and disturbance regimes. These sites represented different communities in terms of species composition. The forest was poorer in species richness, and lower in stem density and basal area than wet forests of the tropics. Across sites (communities), the diversity components and tree density were positively related with total tree basal area. Considering basal area as a surrogate of biomass and net production, diversity is found to be positively associated with productivity. A positive relationship between basal area, tree density and species diversity may be an important characteristic of the dry forest, where recurring disturbance does not permit concentration of biomass or stems in only a few strong competitors. However, the relationships of basal area with density, alpha diversity and evenness remain statistically significant only when data from all sites, including the extremely disturbed one, are used in the analysis. In some sites there was a greater coefficient of variation (CV) of basal area than in others, attributed to patchy distribution of stems and resultant blanks. Therefore, to enhance the tree diversity of these forests, the variability in tree basal area must be reduced by regulating local disturbances. Conservation activities, particularly fuelwood plantations near human settlements, deferred grazing and canopy enrichment through multi-species plantations of nursery-raised or wild-collected seedlings of desirable species within the forest patches of low basal area, will be needed to attain restoration goals, but reforestation programmes will have to be made attractive to the forest-dwelling communities.

scholarly journals Habitat selection of Himalayan Musk Deer Moschus leucogaster (Mammalia: Artiodactyla: Moschidae) with respect to biophysical attributes in Annapurna Conservation Area of Nepal

2021 ◽  
Vol 13 (7) ◽  
pp. 18703-18712
Author(s):  
Bijaya Neupane ◽  
Nar Bahadur Chhetri ◽  
Bijaya Dhami
Keyword(s):  
Endangered Species ◽  
Management Strategies ◽  
Mixed Forest ◽  
Habitat Characteristics ◽  
Musk Deer ◽  
Importance Value Index ◽  
Importance Value ◽  
Conservation Area ◽  
Preferred Habitat ◽  
Annapurna Conservation Area

Himalayan or White-bellied Musk Deer Moschus leucogaster, an IUCN indexed endangered species, is distributed in isolated pockets in the Himalaya. The deer population is decreasing owing to several pressures that include habitat loss and fragmentation, and poaching. It is essential to identify preferred habitat characteristics to support appropriate management strategies for conserving this endangered species. This study was carried out in the Nysheang basin of Annapurna Conservation Area of Nepal to identify habitats preferred by the musk deer. Habitat field parameters were collected using transect surveys. To analyze vegetation use and availability, nested quadrate plots size 20 m2 were established. Ivlev’s electivity index (IV) (-1 to +1) was employed to determine habitat preference, and one-way ANOVA (F) and chi-square tests (χ2) were used to examine different habitat parameters. Similarly, the importance value index (IVI) of the vegetation was calculated. Our results showed that the Himalayan Musk Deer strongly preferred habitats at 3601–3800 m altitude (IV= 0.3, F= 4.58, P <0.05), with 21–30º slope (IV= 0.2, F= 4.14, P <0.05), 26–50 % crown cover (IV= 0.25, F= 4.45, P <0.05), 26–50 % ground cover (IV= 0.15, F= 4.13, P <0.05), and mixed forest (IV= 0.29, χ2= 28.82, df= 3, p <0.001). Among the trees, Abies spectabilis (IVI= 74.87, IV= 0.035) and Rhododendron arboretum (IVI= 55.41, IV= 0.02) were the most preferred, while Rhododendron lepidotum, Cassiope fastigiata (IV= 0.35) and Berberis aristata (IV= 0.25) were the most preferred shrubs, and Primula denticulata (IV= 0.87) and Primula rotundifolia (IV= 0.31) were the most preferred herbs. These preferred habitat conditions should be maintained and conserved to sustain a viable population of deer in the study area. Further studies will be required to assess the effects of climate change on habitat suitability. 

scholarly journals Factors affecting the species richness and composition of bird species in a community managed forest of Nepal

2021 ◽  
Vol 13 (9) ◽  
pp. 19212-19222
Author(s):  
Bishow Poudel ◽  
Bijaya Neupane ◽  
Rajeev Joshi ◽  
Thakur Silwal ◽  
Nirjala Raut ◽  
...  
Keyword(s):  
Diversity Index ◽  
Bird Species ◽  
Habitat Characteristics ◽  
Lower Percentage ◽  
Bird Diversity ◽  
Limited Information ◽  
Managed Forest ◽  
Point Count ◽  
Community Forests ◽  
Wiener Diversity Index

There exists limited information on biodiversity including avifaunal diversity and habitat condition in community forests (CF) of Nepal; thus we aimed to fulfill such gaps in Tibrekot CF of Kaski district. We used the point count method for assessing bird diversity and laid out a circular plot size of radius 5-m within 15-m distance from each point count station for recording the biophysical habitat characteristics. Bird species’ diversity, richness and evenness were calculated using popular indexes and General Linear Model (GLM) was used to test the respective effect of various biophysical factors associated with the richness of bird species. In total, 166 (summer 122, winter 125) bird species were recorded in 46 sample plots. The Shannon-Wiener diversity index was calculated as 3.99 and 4.09, Margalef’s richness index as 16.84 and 17.53 and Pielou’s evenness index as 0.83 and 0.84 for summer and winter, respectively. The influencing factors for richness of bird species were season (χ21, 90= 112.21; P= 0.016) with higher richness in the summer season and low vegetation cover (χ21, 89= 113.88; P= 0.0064) with higher richness in lower percentage cover. Thus, community managed forest should be protected as it has a significant role in increasing bird diversity, which has potential for attracting avifaunal tourism for the benefit of the local communities.

Extensive forest management contributes to maintain suitable habitat characteristics for the endangered Atlantic-Gaspésie caribou

2016 ◽  
Vol 46 (7) ◽  
pp. 933-942 ◽  
Author(s):  
Marie-Audrey Nadeau Fortin ◽  
Luc Sirois ◽  
Martin-Hugues St-Laurent
Keyword(s):  
Forest Management ◽  
Maximum Sustainable Yield ◽  
Habitat Characteristics ◽  
Coniferous Forests ◽  
Suitable Habitat ◽  
Habitat Conditions ◽  
Natural Forests ◽  
Forest Practices ◽  
Partial Canonical Correspondence Analysis ◽  
Conservation Of Endangered Species

Extensive forest management aims at minimizing differences between managed and natural forests and at contributing to the conservation of endangered species such as the Atlantic-Gaspésie caribou. The decline of this isolated population was exacerbated by intensive forest practices, as the over-representation of regenerating forests supports high densities of bears and coyotes. These predators select such stands for the high availability of berries and browse suitable to alternative prey, especially moose. Our objective was to verify whether extensive treatments can provide suitable habitat characteristics for caribou. We compared the impacts of different intensive and extensive treatments on habitat attributes known to be selected by caribou, moose, and their predators. We sampled 291 sites in seven treatments and in mature coniferous forests (as the control). A partial canonical correspondence analysis highlighted which treatments maintain habitat attributes that are comparable with those found in mature forests, including some characteristics suitable for caribou such as a substantial biomass of arboreal lichen and a lower availability of resources for predators. Although being more suitable than the three intensive treatments tested, none of the four extensive treatments we studied provided similar habitat conditions to mature forest. Favouring extensive treatments could nevertheless be a relevant conservation compromise at the forest stand level, but their utility remains uncertain under the maximum sustainable yield paradigm as they impact a larger area.

scholarly journals The mismatch between location of protected areas and suitable habitat for the Vulnerable taruka Hippocamelus antisensis

Oryx ◽  
2018 ◽  
Vol 53 (4) ◽  
pp. 752-756 ◽  
Author(s):  
Cristina Mata ◽  
Nicolás Fuentes-Allende ◽  
Juan E. Malo ◽  
André Vielma ◽  
Benito A. González
Keyword(s):  
Protected Areas ◽  
Protected Area ◽  
Species Distribution Model ◽  
Human Impacts ◽  
Atacama Desert ◽  
Distribution Model ◽  
Suitable Habitat ◽  
Core Habitat ◽  
Preferred Habitat ◽  
Educational Programmes

AbstractProtected areas help to decrease human impacts on threatened mammals but do not always include species’ core habitats. Here we focus on the Vulnerable taruka Hippocamelus antisensis near the Atacama Desert, Chile, a population that is mainly threatened by interactions with local human communities. We develop a species distribution model for taruka and assess the contribution of protected areas to safeguarding its preferred habitat. From sightings (collected during 2004–2015), absence records (collected in 2014), and environmental variables, we determined that taruka habitat is scarce, highly fragmented and limited to humid areas. Only 7.7–11.2% of the taruka's core habitat is under protection. We recommend the establishment of a protected area in the south of Arica-Parinacota district, an area without settlements that lies within the taruka's core habitat, along with educational programmes, fencing of crops, and inclusion of communities in decision-making in areas where farmer–taruka interactions are negative.

Using tree rings to assess the potential of thinning to alleviate drought stress in a dry forest of western Canada

2021 ◽  
Author(s):  
David Montwé ◽  
Audrey Standish ◽  
Miriam Isaac-Renton ◽  
Jodi Axelson
Keyword(s):  
Tree Ring ◽  
Tree Rings ◽  
Basal Area ◽  
Dry Forest ◽  
Tree Level ◽  
Severe Drought ◽  
Western Canada ◽  
Drought Event ◽  
Individual Tree ◽  
Potential Benefits

&lt;p&gt;Increasing frequency of severe drought events under climate change is a major cause for concern for millions of hectares of forested land. One practical solution to improving forest resilience may be thinning. There may be several potential benefits, chief of which is that drought tolerance could be improved in the remaining trees due to lower competition for resources and increased precipitation throughfall. By improving resilience to drought, this may increase productivity of the remaining trees while lowering risks of mortality. Such potential benefits can effectively be quantified with data from statistically-sound, long-term field experiments, and tree rings provide a suitable avenue to compare treatments. We work with an experiment that applied different levels of tree retention to mature interior Douglas fir (&lt;em&gt;Pseudotsuga menziesii&lt;/em&gt; var. &lt;em&gt;glauca&lt;/em&gt;) in a dry ecosystem of western Canada. The treatments were applied in the winter of 2002/2003, coinciding with the aftermath of a severe natural drought event in 2002. We used tree-rings to quantify the extent to which thinning improves recovery and resilience of treated trees as compared to non-thinned controls. Tree-ring samples as well as height and diameter data were obtained from 83 trees from 8 treatment units of the randomized experimental design. Indicators for resilience to drought were calculated based on basal area increments. Thinning substantially increased basal area increments at the individual tree level, but more importantly, led to significantly higher recovery and resilience relative to the control. The results of this tree-ring analysis suggest that thinning may be a viable silvicultural intervention to counteract effects of severe drought events and to maintain tree cover.&lt;/p&gt;

scholarly journals Multiple Factors Influence Seasonal and Interannual Litterfall Production in a Tropical Dry Forest in Mexico

Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1241
Author(s):  
Hernán Morffi-Mestre ◽  
Gregorio Ángeles-Pérez ◽  
Jennifer S. Powers ◽  
José Luis Andrade ◽  
Astrid Helena Huechacona Ruiz ◽  
...  
Keyword(s):  
Linear Models ◽  
Tropical Dry Forest ◽  
Basal Area ◽  
Dry Forest ◽  
Maximum Temperature ◽  
Dry Forests ◽  
Evergreen Species ◽  
Flat Terrain ◽  
Litterfall Production ◽  
Successional Age

Litterfall production plays a fundamental role in the dynamics and function of tropical forest ecosystems, as it supplies 70–80% of nutrients entering the soil. This process varies annually and seasonally, depending on multiple environmental factors. However, few studies spanning several years have addressed the combined effect of climate variables, successional age, topography, and vegetation structure in tropical dry forests. In this study, we evaluated monthly, seasonal, and annual litterfall production over a five-year period in semideciduous dry forests of different successional ages growing on contrasting topographic conditions (sloping or flat terrain) in Yucatan, Mexico. Its relationship with climate and vegetation structural variables were also analyzed using multiple linear regression and generalized linear models. Litterfall was measured monthly in 12 litterfall traps of 0.5 m2 in three sampling clusters (sets of four 400 m2 sampling plots) established in forests of five successional age classes, 3–5, 10–17, 18–25, 60–79, and >80 years (in the latter two classes either on slopping or on flat terrain), for a total of 15 sampling clusters and 180 litterfall traps. Litterfall production varied between years (negatively correlated with precipitation), seasons (positively correlated with wind speed and maximum temperature), and months (negatively correlated with relative humidity) and was higher in flat than in sloping sites. Litterfall production also increased with successional age until 18–25 years after abandonment, when it attained values similar to those of mature forests. It was positively correlated with the aboveground biomass of deciduous species but negatively correlated with the basal area of evergreen species. Our results show a rapid recovery of litterfall production with successional age of these forests, which may increase with climate changes such as less precipitation, higher temperatures, and higher incidence of hurricanes.

scholarly journals Long-Term Effects of Fuels Treatments, Overstory Structure, and Wildfire on Tree Regeneration in Dry Forests of Central Washington

Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 888
Author(s):  
Allison K. Rossman ◽  
Jonathan D. Bakker ◽  
David W. Peterson ◽  
Charles B. Halpern
Keyword(s):  
Prescribed Burning ◽  
Basal Area ◽  
Tree Regeneration ◽  
Dry Forest ◽  
Permanent Plots ◽  
Long Term Effects ◽  
Fuels Reduction ◽  
Forest Fuels ◽  
Fuels Treatments

The long-term effectiveness of dry-forest fuels treatments (restoration thinning and prescribed burning) depends, in part, on the pace at which trees regenerate and recruit into the overstory. Knowledge of the factors that shape post-treatment regeneration and growth is limited by the short timeframes and simple disturbance histories of past research. Here, we present results of a 15-year fuels-reduction experiment in central Washington, including responses to planned and unplanned disturbances. We explore the changing patterns of Douglas-fir regeneration in 72 permanent plots (0.1 ha) varying in overstory abundance (a function of density and basal area) and disturbance history—the latter including thinning, prescribed burning, and/or wildfire. Plots were measured before treatment (2000/2001), soon afterwards (2004/2005), and more than a decade later (2015). Thinning combined with burning enhanced sapling recruitment (ingrowth) into the overstory, although rates of ingrowth were consistently low and greatly exceeded by mortality. Relationships between seedling frequency (proportion of quadrats within a plot) and overstory abundance shifted from weakly negative before treatment to positive after thinning, to neutral in the longer term. However, these relationships were overshadowed by more recent, higher-severity prescribed fire and wildfire that stimulated seedling establishment while killing advanced regeneration and overstory trees. Our results highlight the dependence of regeneration responses on the history of, and time since, fuels treatment and subsequent disturbance. Managers must be aware of this spatial and temporal complexity and plan for future disturbances that are inevitable but unpredictable in timing and severity.

Surveys of Arboreal and Terrestrial Mammals in The Montane Forests of Queanbeyan, New South Wales.

1998 ◽  
Vol 20 (1) ◽  
pp. 9
Author(s):  
R. Goldingay ◽  
G. Daly
Keyword(s):  
New South ◽  
New South Wales ◽  
Dry Forest ◽  
Suitable Habitat ◽  
Pitfall Trapping ◽  
Terrestrial Mammals ◽  
Potential Habitat ◽  
South Wales ◽  
Moist Forest ◽  
Logged Forest

Surveys of arboreal and terrestrial mammals were conducted across four State Forests in south-east New South Wales encompassing 80 000 ha. Methods used included spotlighting, Elliott trapping, pitfall trapping, hair-tubing and predator scat analysis. The survey included a plot-based approach and the targeting of areas containing the potential habitat of endangered species. Seven species of arboreal marsupial were detected during spotlighting. The greater glider (Petauroides volans) was significantly more abundant in moist forest compared to dry forest. Its density in moist forest was twice as high in unlogged compared to logged forest and is equivalent to the highest recorded in any forest in NSW. Other arboreal species were less abundant. The yellow-bellied glider (Petaurus australis), which is Threatened in NSW, was detected at only two sites despite the occurrence of suitable habitat throughout the study area. Eight species of native terrestrial mammals were detected. The tiger quoll (Dasyurus maculatus), which is Threatened in NSW, appears to be more common in the southern part of the study area adjoining large areas of National Park, than in other State Forests of south-east NSW. Continued analysis of predator scats is required to determine whether several other species of Threatened terrestrial mammal occur in these forests.

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