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The article is a critique of the Right of Passage (ROP) document, which identifies elephant corridors in India for conservation purposes. The authors argue that the ROP lacks a working definition of "corridor" and does not use rigorous scientific methods to identify and validate corridors. They also point out that the ROP misses important existing corridors and fails to consider the hierarchical nature of corridor networks. The authors recommend using more objective modeling methods to map and prioritize elephant corridors in India. They emphasize the need for accurate and comprehensive information to guide conservation efforts. [Extracted from the article]

The western Terai Arc Landscape (wTAL) in Uttarakhand, India, marks the range limit for the Asian elephant in north‐western India. This region has been impacted by land‐use changes and infrastructure expansion for the last seven decades. To evaluate the impact of habitat deterioration on the population structure of elephants in the region, we characterized their genetic diversity and local genetic structure using mitochondrial (D loop) and nuclear DNA (microsatellites; n = 15) markers. We used tissue samples of 114 elephants from five different sub‐populations, collected between 2005 and 2014. The genetic variation was moderate (HO = 0.49–0.55) compared with other Indian elephant populations. Two mtDNA haplotypes were identified without strong spatial patterns across wTAL. Bayesian individual‐based clustering algorithm identified two genetic clusters (K = 2) with high admixture (50% at Q < 0.7) and no spatial adherence. Though K = 1 was not supported by the Bayesian algorithm, multivariate analysis and sibship patterns did not indicate genetic differentiation. The lack of spatial genetic structuring suggests high levels of gene flow, indicating that this population is still panmictic. This suggests that the life history traits of elephants as well as the ecological features of this landscape influence genetic connectivity. However, ongoing land use changes necessitate regular genetic monitoring in wTAL to identify incipient structuring caused by anthropogenic barriers to movement. [ABSTRACT FROM AUTHOR]

The Asian elephant is mostly confined to mountainous ranges and therefore risks population fragmentation if hard protected area (PA) boundaries near steep slopes prevent movement. We tested whether elephant gene flow is (i) controlled by slope and (ii) affected by the interplay between barriers and slope. We used 176 unique genotypes obtained non-invasively from fresh elephant dung to assess individual-by-individual genetic distance across the Western Ghats of India, a biodiversity hotspot. To assess landscape distance, 36 resistance models were produced by transforming a slope raster. Core areas and corridors were calculated from the raster that provided the best correlation between the genetic and distance matrices. The influence of the closure of PAs on gene flow was examined for one region, the Nilgiri Biosphere Reserve. The best resistance raster obtained by transforming the slope occupancy model was better than Euclidean distance for explaining genetic distance, indicating that slope partially controls gene flow. Fencing elephant PAs on hilly terrain reduces core areas and disrupts corridors. Consequently, hard PA boundaries abutting slopes can fragment elephant populations, but this can be ameliorated by protecting the adjacent flatter terrain. [ABSTRACT FROM AUTHOR]

Management of wildlife depends mostly on scientific data; ignoring this can lead to unintended consequences. We take the case study of the wild male Asian Elephant Rivaldo of the Sigur Region, who was translocated out of his range. Rivaldo returned to his home range within a few days, which could have been expected if scientific publications had been consulted. We suggest that a simple checklist of relevant publications can help park managers to decide on a proper management procedure. We also used a simple Bayesian framework to visually show how the probability of predicting a management outcome is increased by prior knowledge. The expensive and risky effort to relocate the elephant could have been avoided altogether if prior knowledge had been taken into consideration. [ABSTRACT FROM AUTHOR]

Aim: Climate change alters the water cycle, potentially affecting the distribution of species. Using an ensemble of species distribution models (SDMs), we predicted changes in distribution of the Asian elephant in South Asia due to increasing climatic variability under warming climate and human pressures. Location: India and Nepal. Methods: We compiled a comprehensive geodatabase of 115 predictor variables, which included climatic, topographic, human pressures and land use, at a resolution of 1 km2, and an extensive database on current distribution of elephants. For variable selection, we first developed 14 candidate models based on different hypotheses on elephant habitat selection. For each candidate model, a series of 240 individual models were evaluated using several metrics. Using three climatic and one land use change datasets for two greenhouse gas scenarios, ensemble SDMs were used to predict future projections. Results: Nine predictor variables were selected for ensemble SDMs. Elephant distribution is driven predominantly by changes in climatic water balance (>60%), followed by changes in temperature and human‐induced disturbance. The results suggest that around 41.8% of the 256,518 km2 of habitat available at present will be lost by the end of this century due to combined effects of climate change and human pressure. Projected habitat loss will be higher in human‐dominated sites at lower elevations due to intensifying droughts, leading elephants to seek refuge at higher elevations along valleys with greater water availability in the Himalayan Mountains. Main conclusions: Changes in climatic water balance could play a crucial role in driving species distributions in regions with monsoonal climates. In response, species would shift their range upwards along gradients of water availability and seasonal droughts. Conservation and management of elephant populations under global change should include design of movement corridors to enable dispersal of the elephant and other associated species to more conducive environments. [ABSTRACT FROM AUTHOR]

A ratio-based logistic model developed to assess elephant harvest rates, based on a study at Nagarhole Tiger Reserve in India, was recommended as a management tool to control human–elephant conflict through culling. Considering this reserve among others violates an assumption of the logistic model: isolation. Nevertheless, assuming this violation was irrelevant, we re-evaluated the model, with minor modifications, for the neighbouring Mudumalai Tiger Reserve, where we used data from 13 elephant Elephas maximus population surveys to derive bootstrapped sets of population ratios, and mortality records. We generated arrays of harvest regimes and examined which ratio outputs were closest to the bootstrapped ratios. Our results indicated that (1) model outputs corresponded best with the Mudumalai population structure when harvest regimes were extreme and unlikely, (2) there were significant differences in population structure and harvest regimes between Nagarhole and Mudumalai, and (3) only 49% of adult male deaths predicted by model outputs were recorded in official governmental records. The model provides significantly different results among reserves, which invalidates it as a tool to predict change across the entire elephant population. Variability in survey data and inaccuracies in transition probabilities are sufficiently large to warrant caution when using them as a basis for deterministic modelling. Official mortality databases provide a weak means of validation because poaching incidents are poorly recorded. We conclude that the model should be based on validated transition probabilities and encompass the entire regional population. [ABSTRACT FROM PUBLISHER]

The article reports that South and Southeast Asian countries must protect and restore ecological connectivity between elephant habitats and accelerate trans boundary conservation networks through international cooperation to increase genetic diversity, and preserve ecosystem.

We compiled records of 291 elephant deaths over a 33-year period (1979-2011) from the Mudumalai Tiger Reserve and the reserved forests of Nilgiri North and South divisions of southern India from the databases of the Tamil Nadu Forest Department, the Wildlife Protection Society of India and the Nilgiri Wildlife and Environment Association. We tested the null hypothesis that the causes of elephant deaths would not differ with time, by gender and with level of protection. We classified records by gender and age: adults (=15 years), sub adults (5-15 years), juveniles (>1-<5) and calves (= 1). We organised records over 3-decade periods. The database consisted of 209 adults (=15 years), 27 sub adults (5-15 years), 33 juveniles (>1-<5) and 22 calves (= 1). MTR had the maximum records (148) followed by NND (138) and NSD (4). The median age of death was 20 years for adult males and 30 years for adult females. Mean survival time for adult males was 22.45 years, and 31.84 for females. Poaching was responsible for the majority of deaths (40%), particularly of male elephants (82%), and unknown causes (31%) for the majority of female deaths (66%). Human-caused deaths, which included poaching and some accidents, averaged 72% between 1979 and 2000 and decreased to 22% during 2001-2011. Deaths due to unknown causes and diseases increased from 28% in 1979-1989 to 69% in 2001-2011. Relative to estimated population size, deaths attributed to poaching was higher in NND (47%) than in MTR (34%). The causes of death differed by region. In conclusion, the elephant population in the Nilgiris is at risk and needs stringent protection; the mortality database should be systematised; forensic capabilities upgraded, and detection of carcasses improved. [ABSTRACT FROM AUTHOR]