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1.
Conserv Biol ; 32(6): 1313-1324, 2018 12.
Article in English | MEDLINE | ID: mdl-29855078

ABSTRACT

The Himalayas are a global biodiversity hotspot threatened by widespread agriculture and pasture expansion. To determine the impact of these threats on biodiversity and to formulate appropriate conservation strategies, we surveyed birds along elevational gradients in primary forest and in human-dominated lands spanning a gradient of habitat alteration, including forest-agriculture mosaics, mixed agriculture mosaics, and pasture. We surveyed birds during the breeding season and in winter to account for pronounced seasonal migrations. Bird abundance and richness in forest-agriculture and mixed agriculture mosaics were equal to or greater than in primary forest and greater than in pasture at local and landscape scales during both seasons. Pasture had greater abundance and richness of birds in winter than primary forest, but richness was greater in primary forest at the landscape scale during the breeding season. All 4 land-use types held unique species, suggesting that all must be retained in the landscape to conserve the entire avifauna. Our results suggest forest-agriculture and mixed agriculture mosaics are particularly important for sustaining Himalayan bird communities during winter and primary forests are vital for sustaining Himalayan bird communities during the breeding season. Further conversion of forest-agriculture and mixed agriculture mosaics to pasture would likely result in significant biodiversity losses that would disproportionately affect breeding species. To ensure comprehensive conservation, strategies in the western Himalayas must balance the protection of intact primary forest with the minimization of pasture expansion.


Subject(s)
Conservation of Natural Resources , Forests , Agriculture , Animals , Biodiversity , Birds , Ecosystem , Seasons
2.
Conserv Biol ; 31(2): 416-426, 2017 04.
Article in English | MEDLINE | ID: mdl-27558794

ABSTRACT

The impacts of land-use change on biodiversity in the Himalayas are poorly known, notwithstanding widespread deforestation and agricultural intensification in this highly biodiverse region. Although intact primary forests harbor many Himalayan birds during breeding, a large number of bird species use agricultural lands during winter. We assessed how Himalayan bird species richness, abundance, and composition during winter are affected by forest loss stemming from agriculture and grazing. Bird surveys along 12 elevational transects within primary forest, low-intensity agriculture, mixed subsistence agriculture, and intensively grazed pastures in winter revealed that bird species richness and abundance were greatest in low-intensity and mixed agriculture, intermediate in grazed pastures, and lowest in primary forest at both local and landscape scales; over twice as many species and individuals were recorded in low-intensity agriculture than in primary forest. Bird communities in primary forests were distinct from those in all other land-use classes, but only 4 species were unique to primary forests. Low-, medium-, and high-intensity agriculture harbored 32 unique species. Of the species observed in primary forest, 80% had equal or greater abundance in low-intensity agricultural lands, underscoring the value of these lands in retaining diverse community assemblages at high densities in winter. Among disturbed landscapes, bird species richness and abundance declined as land-use intensity increased, especially in high-intensity pastures. Our results suggest that agricultural landscapes are important for most Himalayan bird species in winter. But agricultural intensification-especially increased grazing-will likely result in biodiversity losses. Given that forest reserves alone may inadequately conserve Himalayan birds in winter, comprehensive conservation strategies in the region must go beyond protecting intact primary forests and ensure that low-intensity agricultural lands are not extensively converted to high-intensity pastures.


Subject(s)
Agriculture , Birds , Conservation of Natural Resources , Animals , Biodiversity , Ecosystem , Forests
3.
Ecology ; 98(2): 337-348, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27869987

ABSTRACT

There is clear evidence that species' ranges along environmental gradients are constrained by both biotic and abiotic factors, yet their relative importance in structuring realized distributions remains uncertain. We surveyed breeding bird communities while collecting in situ temperature and vegetation data along five elevational transects in the Himalayas differing in temperature variability, habitat zonation, and bird richness in order to disentangle temperature, habitat, and congeneric competition as mechanisms structuring elevational ranges. Our results from species' abundance models representing these three mechanisms differed markedly from previous, foundational research in the tropics. Contrary to general expectations, we found little evidence for competition as a major determinant of range boundaries, with congeneric species limiting only 12% of ranges. Instead, temperature and habitat were found to structure the majority of species' distributions, limiting 48 and 40% of ranges, respectively. Our results suggest that different mechanisms may structure species ranges in the temperate Himalayas compared to tropical systems. Despite recent evidence suggesting temperate species have broader thermal tolerances than tropical species, our findings reinforce the notion that the abiotic environment has significant control over the distributions of temperate species.


Subject(s)
Biodiversity , Birds , Ecosystem , Temperature , Animals , Population Dynamics
4.
PLoS One ; 10(6): e0127626, 2015.
Article in English | MEDLINE | ID: mdl-26061171

ABSTRACT

Tiger (Panthera tigris), an endangered species, is under severe threat from poaching, habitat loss, prey depletion and habitat disturbance. Such factors have been reported causing local extermination of tiger populations including in one of the most important reserves in India, namely Sariska Tiger Reserve (STR) in northwestern India. Consequently, tigers were reintroduced in STR between 2008 and 2010, but inadequate breeding success was observed over the years, thus invoking an investigation to ascertain physiological correlates. In the present study, we report glucocorticoid stress responses of the reintroduced tigers in relation to anthropogenic disturbance in the STR from 2011 to 2013. We found anthropogenic disturbance such as encounter rates of livestock and humans, distance to roads and efforts to kill domestic livestock associated with an elevation in fecal glucocorticoid metabolite (fGCM) concentrations in the monitored tigers. In this regard, female tigers seem more sensitive to such disturbance than males. It was possible to discern that tiger's fGCM levels were significantly positively related to the time spent in disturbed areas. Resulting management recommendations include relocation of villages from core areas and restriction of all anthropogenic activities in the entire STR.


Subject(s)
Ecosystem , Endangered Species , Glucocorticoids/analysis , Stress, Physiological , Tigers/physiology , Animals , Feces/chemistry , Female , India , Male
5.
Ind Psychiatry J ; 23(2): 101-4, 2014.
Article in English | MEDLINE | ID: mdl-25788798

ABSTRACT

CONTEXT: Aging of population is currently a global phenomenon. At least one in 5 people over the age of 65 years will suffer from a mental disorder by 2030. Study of psychiatric morbidities in this age group is essential to prepare for upcoming challenges. AIMS: To find out the prevalence of different psychiatric morbidities in elderly population and to find out if there are any age and gender specific differences. SETTINGS AND DESIGN: Retrospective review; Psychiatric outpatient department of Manipal Teaching Hospital, Pokhara, Nepal. MATERIALS AND METHODS: Data for patients ≥ 65 years of age attending the psychiatric outpatient department of Manipal Teaching Hospital, Pokhara, Nepal, from 1(st) January 2012 to 15(th) January 2013 were collected retrospectively in a predesigned proforma. STATISTICAL ANALYSIS USED: Risk of having different psychiatric disorders was estimated using odds ratio. RESULTS: The mean age of 120 patients included in this study was 69.67 (SD = 5.94) years. Depressive disorder (26.7%) was the most common diagnosis. There was no statistically significant difference in psychiatric disorders in >75 years compared with ≤75 years except for dementia [odd ratio (OR) (≤75 years/>75 years)=0.055, 95% confidence interval (CI)=0.016; 0.194]. Alcohol dependence syndrome [OR (male/female)=7.826, 95% CI = 1.699;36.705] and dementia [OR (male/female)=3.394, 95% CI = 1.015;11.350] was more common in males. CONCLUSIONS: Depressive disorder was the most common psychiatric morbidity among the elderly patients. The odds suffering from dementia increased with increasing age. The odds of having alcohol related problems and dementia were more in males compared with females.

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