Examining Temporal Sample Scale and Model Choice with Spatial Capture-Recapture Models in the Common Leopard \u3ci\u3ePanthera pardus\u3c/i\u3e

Many large carnivores occupy a wide geographic distribution, and face treats from habitat loss and fragmentation, poaching, prey depletion, and human wildlife-conflicts. Conservation requires robust techniques for estimating population densities and trends, but the elusive nature and low densities of many large carnivores make them difficult to detect. Spatial capture-recapture (SCR) models provide a means for handling imperfect detectability, while linking population estimates to individual movement patterns to provide more accurate estimates than standard approaches. Within this framework, we investigate the effect of different sample interval lengths on density estimates, using simulations and a common leopard (Panthera pardus) model system. We apply Bayesian SCR methods to 89 simulated data sets and camera-trapping data from 22 leopards captured 82 times during winter 2010-2011 in Royal Manas National Park, Bhutan. We show that sample interval length from daily, weekly, monthly or quarterly periods did not appreciably affect median abundance or density, but did influence precision. We observed the largest gains in precision when moving from quarterly to shorter intervals. We therefore recommend daily sampling intervals for monitoring rare or elusive species where practicable, but note that monthly or quarterly sample periods can have similar informative value. We further develop a novel application of Bayes factors to select models where multiple ecological factors are integrated into density estimation. Our simulations demonstrate that these methods can help identify the true explanatory mechanisms underlying the data. Using this method, we found strong evidence for sex-specific movement distributions in leopards, suggesting that sexual patterns of space-use influence density. This model estimated a density of 10.0 leopards/100 km2 (95% credibility interval: 6.25-15.93), comparable to contemporary estimates in Asia. These SCR methods provide a guide to monitor and observe the effect of management interventions on leopards and other species of conservation interest

Royal Manas National Park, Bhutan: A Hot Spot for Wild Felids

The non-uniformity of the distribution of biodiversity makes allocation of the limited resources available for conservation of biodiversity a difficult task. Approaches such as biodiversity hotspot identification, endemic bird areas, crisis ecoregions, global 200 ecoregions, and the Last of the Wild are used by scientists and international conservation agencies to prioritize conservation efforts. As part of the biodiverse Eastern Himalayan region, Bhutan has been identified as a conservation priority area by all these different approaches, yet data validating these assessments are limited. To examine whether Bhutan is a biodiversity hot spot for a key taxonomic group, we conducted camera trapping in the lower foothills of Bhutan, in Royal Manas National Park, from November 2010 to February 2011. We recorded six species of wild felids of which five are listed on the IUCN Red List: tiger Panthera tigris, golden cat Pardofelis temminckii, marbled cat Pardofelis marmorata, leopard cat Prionailurus bengalensis, clouded leopard Neofelis nebulosa and common leopard Panthera pardus. Our study area of 74 km(2) has c. 16% of felid species, confirming Bhutan as a biodiversity hot spot for this group

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Estimating the response of Himalayan old-growth mountain forests to decreased monsoon precipitation

Forests in the Himalayas are a major carbon store, but are under threat due to changes in precipitation regime. To simulate a precipitation decline, throughfall-exclusion (TFE) shelters were applied during three consecutive monsoon seasons in an oak forest (2.650 m a.s.l.) and a conifer-dominated forest (3.260 m a.s.l.) in central Bhutan. Leaf water potentials, tree mortality, stem increment, soil CO2 efflux, litterfall and fine root dynamics were assessed. TFE significantly and consistently decreased topsoil (0–30 cm) moisture and leaf water potentials of Quercus lanata and Quercus griffithii (lower elevation), and to a lesser extend those of Tsuga dumosa and Quercus semecarpifolia, (higher elevation). TFE did not impose tree mortality. Stem increment remained unaffected until the second TFE year, but showed reductions during the third year with Tsuga dumosa being most severely affected (-60%). Standing fine root biomass stocks were hardly affected by TFE. Increased root necromass and faster fine root growth in the lower elevation forest suggest that the oak trees increased C allocation below ground. Soil CO2 efflux sharply declined during all three TFE years in both forests. Above ground litter input was unaffected by TFE until the second treatment year. Overall, both forest ecosystems appeared highly resistant to the imposed soil drying, with no signs of tree mortality and stable living root biomass stocks.ISSN:0168-1923ISSN:1873-224

Tiger reappearance in Bhutan's Bumdeling Wildlife Sanctuary: a case for maintaining effective corridors and metapopulations

The tiger Panthera tigris is globally 'Endangered'(Goodrich et al., 2015). The Himalayan Kingdom of Bhutan is an important stronghold (Tempa et al., 2019) for this ecologically and economically important apex predator (Estes et al., 2011; Thinley et al., 2018). Here, we report the reappearance of the tiger in Bumdeling Wildlife Sanctuary (BWS) in north-eastern Bhutan (Fig. 1a), after a likely absence of 12 years