Elephant Research Articles

Non-volatile cysteine sulphoxides and volatile organosulphur compounds in cloves of garlic (Allium sativum L.) and elephant garlic (Allium ampeloprasum L.) local accessions from northern and central Italy.

Garlic (Allium sativum L.) and other species of genus Allium are popular vegetables and food seasonings, owing to their spicy flavour and richness in health-promoting compounds. Several local garlic types are still grown on a small scale in different Italian regions, not being however yet properly characterized for their chemical composition. In the present investigation ten garlic and four elephant garlic (Allium ampeloprasum L.) populations cultivated in northern and central Italy were evaluated for their alk(en)yl cysteine sulphoxide (ACSO) and volatile compound profiles. Three non-volatile ACSOs (methiin, alliin, and isoalliin) and 27 volatile compounds were identified and quantified. A high and significant within-type variability was detected, with total ACSOs in the range 2759-5756, 4533-15 520, and 6565-10 643 mg kg-1 of fresh weight (f.w.). in elephant, white and red garlic, respectively. Elephant garlic showed a total sulphoxide content and a relative alliin amount significantly lower than white and red garlic. Remarkable within-type differences were also assessed for volatile compound content, ranging 260-599, 333-981, and 618-845 mg kg-1 f.w. in elephant, white, and red garlic, respectively. Diallyl trisulphide was the major individual compound, accounting for more than 0.30 mg mg-1 of volatiles in all the analysed samples. The three garlic types were clearly separated by discriminant analysis of analytical traits. This study investigated for the first time different Italian garlic and elephant garlic populations with respect to non-volatile and volatile organosulphur compound content, allowing the possibility of selecting garlic accessions according to the bioactive content. © 2022 Society of Chemical Industry.

Population genetic structure of the elephant tick Amblyomma tholloni from different elephant populations in Kenya

Understanding factors that shape tick population genetic structure is important as they may be exploited in crafting strategies for vector control. Amblyomma tholloni, or “elephant tick” is a three-host tick whose adults preferentially parasitize African elephants. The aim of this study was to determine the influence of fragmentation of the host populations on the genetic structure of this tick species from different ecosystems in Kenya, using the second internal transcribed spacer (ITS-2) and mitochondrial cytochrome oxidase 1 (CO1) loci. Population genetic analysis of ticks collected from four elephant populations using ITS-2 and CO1 loci revealed high gene diversity. Gene diversity at the ITS-2 locus was 0.91 and the nucleotide diversity was, 0.01. ITS-2 gene diversity was highest in Laikipia-Samburu ecosystem (0.947) and lowest in Tsavo (0.80). The CO1 locus also had high gene diversity, 0.790, and low nucleotide diversity, 0.006, and like ITS-2, gene diversity was higher in Laikipia-Samburu ecosystem (1.00) and lower in Tsavo (0.286). There was a modest statistically significant genetic differentiation among the four tick populations based on ITS-2 (FST = 0.104, P < 0.001; ΦST = 0.105, P < 0.001), and a 10% of molecular variance attributed to genetic variation between populations. There was also statistically significant differentiation among tick populations using haplotype frequencies for CO1 locus (FST = 0.167, P < 0.001) accounting for 17% of genetic variance among populations, but not modelled genetic distances (ΦST = 0.029, P = 0.095) suggesting very recent genetic differentiation. In addition, populations of A. tholloni in Kenya had a significantly negative Tajima D and Fu & Li's F* and D* at the CO1 locus suggesting recent positive selection. The extensive acaricide use in livestock, which host the larval stage, could be driving purifying selection and genetic hitchhiking of the CO1 locus. However, tests sensitive to demography such as Fu's FS, Ramos-Onsins & Rozas's R2 and raggedness index r were statistically significant at the ITS-2 locus suggesting ancient demographic expansion. Elephant population fragmentation appears to shape the genetic structure of A. tholloni, while agro-ecological factors could influence the genetic diversity of ticks.

Constraints, crashes and conservation: were historical African savanna elephants Loxodonta africana densities relatively high or lower than those seen in protected areas today?

ABSTRACT African savanna elephants (Loxodonta africana) are significant ecosystem engineers – having profound effects on the vegetation when at high population densities. To provide a context for modern conservation decisions it would be useful to know the ‘natural’ population densities prior to the arrival of firearms in Africa. Here, we use botanical and archaeological arguments to suggest a lower density of elephant populations than in some present protected areas over at least the last few millennia, and arguably much longer. This suggests that elephant population densities seen in some protected areas during the second half of the twentieth century are likely higher than those seen in the past and so have the potential to result in significant negative impacts on associated fauna and flora.

Sanksi Pidana terhadap Pelaku Perburuan Gading Gajah di Indonesia

Humans as social beings have different behaviors, traits and attitudes from one another. Humans do various ways to meet their needs, one of which is hunting. Hunting for elephant tusks is one of the causes of the decline in the elephant population. Thus, criminal sanctions against the perpetrators are one of the things that need to be considered to keep the elephant population from becoming extinct. This research aims to reveal the form of criminal sanctions against perpetrators of poaching elephant ivory in Indonesia. The method used is a normative legal research method with an approach to legal norms in accordance with the applicable laws and regulations. Sources of data used in the form of primary, secondary and tertiary data. Data were analyzed by descriptive method. The analyzed data reveals that the legal regulation regarding the prohibition of hunting for elephant ivory in Indonesia is contained in Article 21 paragraph (2) of Law Number 5 of 1990 and Article 17 jo. Article 20 of Government Regulation Number 13 of 1994. Criminal sanctions against perpetrators of poaching elephant ivory are regulated in Article 40 of Law Number 5 of 1990. Law enforcers are expected to provide the fairest sanctions and can provide a deterrent effect to perpetrators so that perpetrators and potential perpetrators do not do the same thing.

Human-elephant conflict: challenges in agriculture Sector in Polonnaruwa district; A study based on literature review

Human-elephant conflict is a major challenge to support the survivors and survival of elephants in tropical countries. Elephant-human conflicts occur when it comes to farmland and chena plantations scattered over a large area. In addition, we can say that the elephant population has decreased significantly due to human-elephant conflicts in the last few decades. The North Central Province of Sri Lanka has been designated as a high-risk area with 42% incidents. This study is based on the Polonnaruwa district, to identify the nature of the human-elephant conflict. In addition, the current elephant-human conflict challenges in agriculture and farming and the search for causes of elephant deaths have been reviewed. Primary and secondary sources were used to systematically review the concepts of the elephant-human conflict and the identified features related to agriculture, farming, and the challenges faced by elephants. Causes of elephant-human conflict, crop damage, property damage, human death, and other damages have been discussed. The theme of the review is local measures taken by farmers to reduce conflicts, government measures low compensation methods for victims, use of bio fences, and use of electric fences. The elephant-human conflict has become a major socio-environmental issue in Sri Lanka. Although human-elephant conflict can be eliminated through inter-cooperation, methodological research has recommended the implementation of the challenges of minimizing human-elephant conflict in the Polonnaruwa district.

Elephant Endotheliotropic Herpesvirus 1, 4 and 5 in China: Occurrence in Multiple Sample Types and Implications for Wild and Captive Population Surveillance.

Elephant endotheliotropic herpesviruses (EEHVs) are important causes of death in both captive and wild Asian elephants (Elephas maximus). Nothing is known about the prevalence of EEHVs in wild or domestic elephants in China. To determine if EEHVs are present in elephants in China, 126 wild elephants from three populations and 202 captive individuals from zoos (n = 155) and the Wild Elephant Valley (n = 47) were screened using semi-nested polymerase chain reaction assays with EEHV-redundant and EEHV1/4/5-specific primers. EEHV1B and EEHV4 were detected in samples from both wild (EEHV1B:8/126; EEHV4:2/126) and captive (EEHV1B:5/155; EEHV4:9/155) elephants, while EEHV1A (six cases) and EEHV5 (one case) were only present in the captive elephants from the Wild Elephant Valley. EEHV1 was detected in blood and trunk and oral swabs; EEHV4 was detected in trunk and oral swabs as well as feces; EEHV5 was found in trunk and oral swabs. No significant age or sex association with EEHV1A, EEHV1B, or EEHV5 positivity was observed. An age association with EEHV4 positivity was found, with all unweaned elephants being EEHV4 positive, but an association with the sex of the elephant was not observed. These findings represent the first documentation of EEHV presence in captive and wild elephants in China. These findings also document EEHV1B and EEHV4 shedding in feces and demonstrate the utility of fecal screening as a tool for investigating EEHV4 infection in wild populations of elephants. It is recommended that EEHV testing be included in surveillance programs for captive and wild elephants in China.

Some population characteristics and viability of captive Asian elephant (Elephas maximus) in Thailand

Abstract. Pla-ard M, Sukmasuang R, Uthairasmee S. 2022. Some population characteristics and viability of captive Asian elephant (Elephas maximus) in Thailand. Biodiversitas 23: 1072-1081. Sustaining long-term viable populations of captive Asian elephants poses a challenge in managing the existing populations. Therefore, studies of the characterization and long-term persistence of the population are an important aspect of the action. The results of long-term population analysis of captive Asian elephants (Elephas maximus Linnaeus, 1758) using Population Viability Analysis (PVA) from the demography information showed that the birth and reproductive rate of the captive elephants in Thailand are declining significantly while the mortality rate trends are stable. Analysis results of the population's ability to persist in the long term from the initial population of 4,252 elephants, it was found that extinction of the population if the percentage adult female breeding is 80%, which is the best-case scenario, if the mortality rate increases by 6% from the present, the population will start going into extinction. If the percentage adult female breeding is set to 2.3%, which is the lowest breeding condition in captive Asian elephants, the population will become extinct in every scenario. Therefore, the most important method in maintaining the captive Asian elephant population is to increase the birth rate improve the well-being, health, nutrition, environment, and welfare of elephants in captivity are important factors that would reduce deaths and are very important for the long-term survival of the population in Thailand.

Landscape characteristics influence ranging behavior of Asian elephants at the human-wildlands interface in Myanmar

ContextAsian elephant numbers are declining across much of their range driven largely by serious threats from land use change resulting in habitat loss and fragmentation. Myanmar, holding critical range for the species, is undergoing major developments due to recent sociopolitical changes. To effectively manage and conserve the remaining populations of endangered elephants in the country, it is crucial to understand their ranging behavior.ObjectivesOur objectives were to (1) estimate the sizes of dry, wet, and annual ranges of wild elephants in Myanmar; and quantify the relationship between dry season (the period when human-elephant interactions are the most likely to occur) range size and configurations of agriculture and natural vegetation within the range, and (2) evaluate how percentage of agriculture within dry core range (50% AKDE range) of elephants relates to their daily distance traveled.MethodsWe used autocorrelated kernel density estimator (AKDE) based on a continuous-time movement modeling (ctmm) framework to estimate dry season (26 ranges from 22 different individuals), wet season (12 ranges from 10 different individuals), and annual range sizes (8 individuals), and reported the 95%, 50% AKDE, and 95% Minimum Convex Polygon (MCP) range sizes. We assessed how landscape characteristics influenced range size based on a broad array of 48 landscape metrics characterizing aspects of vegetation, water, and human features and their juxtaposition in the study areas. To identify the most relevant landscape metrics and simplify our candidate set of informative metrics, we relied on exploratory factor analysis and Spearman’s rank correlation coefficient. Based on this analysis we adopted a final set of metrics into our regression analysis. In a multiple regression framework, we developed candidate models to explain the variation in AKDE dry season range sizes based on the previously identified, salient metrics of landscape composition.ResultsElephant dry season ranges were highly variable averaging 792.0 km2 and 184.2 km2 for the 95% and 50% AKDE home ranges, respectively. We found both the shape and spatial configuration of agriculture and natural vegetation patches within an individual elephant’s range play a significant role in determining the size of its range. We also found that elephants are moving more (larger energy expenditure) in ranges with higher percentages of agricultural area.ConclusionOur results provide baseline information on elephant spatial requirements and the factors affecting them in Myanmar. This information is important for advancing future land use planning that takes into account space-use requirements for elephants. Failing to do so may further endanger already declining elephant populations in Myanmar and across the species’ range.

Assessing Coagulation Parameters in Healthy Asian Elephants (Elephas maximus) from European and Thai Populations

Simple SummaryAsian elephants (Elephas maximus) are considered endangered and their population is in continuous decline. Understanding their social interactions, health, and welfare status has been a topic of intense research in recent decades. Coagulation assessments have been underutilized in wildlife but can give valuable information on individual health. This study aims to increase the knowledge of the coagulation status in healthy Asian elephants from different backgrounds and age groups, using a fast point-of-care analyzer. This tool can be further used in either routine health check-ups performed by caretakers or in a clinical emergency, such as in cases of elephant endotheliotropic herpesvirus hemorrhagic disease outbreaks. We have also investigated the presence of genomic mutations in one coagulation factor—factor VII—where a disorder was previously reported in an Asian elephant. Hereby, we report new reference values for coagulation parameters, such as coagulation times and fibrinogen concentration of Asian elephants assessed in Thailand and in Europe, as well as several single point mutations found in the exons of Elephas maximus coagulation F7 gene. We found the point-of-care analyzer used in this study to be very practical and user friendly for a zoo and field environment and hope that this project will incentivize further coagulation studies in Asian elephants and in other wildlife species.The Asian elephant population is continuously declining due to several extrinsic reasons in their range countries, but also due to diseases in captive populations worldwide. One of these diseases, the elephant endotheliotropic herpesvirus (EEHV) hemorrhagic disease, is very impactful because it particularly affects Asian elephant calves. It is commonly fatal and presents as an acute and generalized hemorrhagic syndrome. Therefore, having reference values of coagulation parameters, and obtaining such values for diseased animals in a very short time, is of great importance. We analyzed prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen concentrations using a portable and fast point-of-care analyzer (VetScan Pro) in 127 Asian elephants from Thai camps and European captive herds. We found significantly different PT and aPTT coagulation times between elephants from the two regions, as well as clear differences in fibrinogen concentration. Nevertheless, these alterations were not expected to have biological or clinical implications. We have also sequenced the coagulation factor VII gene of 141 animals to assess the presence of a previously reported hereditary coagulation disorder in Asian elephants and to investigate the presence of other mutations. We did not find the previously reported mutation in our study population. Instead, we discovered the presence of several new single nucleotide polymorphisms, two of them being considered as deleterious by effect prediction software.

Ionized Calcium and Serum Electrolytes Profile in Captive Asian Elephants (Elephas maximus) of Tamil Nadu, India

Background: Serum electrolyte monitoring is essential in the health assessment of captive elephants. The major elements of calcium, sodium, potassium, chloride and bicarbonate are playing a major role in regulation of nerve and muscle functions and in maintaining acid base and water balance. Excess levels or loss of particular electrolytes may occur as secondary changes caused by certain diseases or changes in physiological regulations. The aim of this study was to evolve the baseline reference values for serum electrolyte levels in captive Asian elephants raised in Tamil Nadu state of India. Methods: As part of the periodical health assessment blood samples were collected from auricular vein for 42 apparently healthy captive Asian elephants in Tamil Nadu, India. Serum electrolyte levels such as sodium (Na+), potassium (K+), chloride (Cl-), ionized calcium (iCa), non-ionized calcium and total calcium (tCa) were determined by using an automated electrolyte analyzer. Result: Most of the ranges of electrolyte values observed in this study were similar to that of previous reports. As not much studies on ionized calcium are available on captive Asian elephants the value of ionized calcium found this study 1.16±0.13 mmol/L could serve as reference. There was no much variation observed in various age groups. This electrolyte profile values will serve as baseline values to evaluate the health and clinical conditions of captive elephant populations.

Simulated poaching affects global connectivity and efficiency in social networks of African savanna elephants-An exemplar of how human disturbance impacts group-living species.

Selective harvest, such as poaching, impacts group-living animals directly through mortality of individuals with desirable traits, and indirectly by altering the structure of their social networks. Understanding the relationship between disturbance-induced, structural network changes and group performance in wild animals remains an outstanding problem. To address this problem, we evaluated the immediate effect of disturbance on group sociality in African savanna elephants-an example, group-living species threatened by poaching. Drawing on static association data from ten free-ranging groups, we constructed one empirically based, population-wide network and 100 virtual networks; performed a series of experiments 'poaching' the oldest, socially central or random individuals; and quantified the immediate change in the theoretical indices of network connectivity and efficiency of social diffusion. Although the social networks never broke down, targeted elimination of the socially central conspecifics, regardless of age, decreased network connectivity and efficiency. These findings hint at the need to further study resilience by modeling network reorganization and interaction-mediated socioecological learning, empirical data permitting. The main contribution of our work is in quantifying connectivity together with global efficiency in multiple social networks that feature the sociodemographic diversity likely found in wild elephant populations. The basic design of our simulation makes it adaptable for hypothesis testing about the consequences of anthropogenic disturbance or lethal management on social interactions in a variety of group-living species with limited, real-world data.

Current Population Status of Asian Elephant in Keonjhar Wildlife Division, Odisha

The Population of Wild elephants (<i>Elephas maximus</i>) is declining worldwide; therefore understanding the dynamics of the remaining population is critical for effective conservation. We monitored the population and distribution of elephants in Keonjhar wildlife division during 2015 and 2017. The Asian elephant (Elephas maximus) is facing a severe threat to its survival from large scale habitat losing and degradation, negative interaction between human and elephant and poaching across its range. India holds by far the largest number of wild Asian elephants, estimate as about 60% population of the species. <i>Elephas</i> <i>maximus</i> is placed in schedule 1 and part 1 of Indian wildlife protection Act (1972) conferring the highest level of protection. Most of the sightings were recorded near water bodies, foot paths & salt licks. During census period 2017 total 49 elephants were sighted out of which 25 were in Hadgarh, 15 in Deogaon, 9 in Brahmanipal Range. Simillarly in 2015 total 51 elephants were counts out of which 25 were in hadgarh, 16 in Dogaon, 9 in Brahmanipal Range It was found that in 2017 population of adult cow was high (43%) followed by calf (21%), adult bull (16%), sub adult cow (6%) and juvenile (4%). Simillarly in 2015 population of adult cow was high (33.33%) followed by sub-adult cow (19.60%), calf (17.64%), adult bull (13.72%), sub-adult bull (11.76%), adult/sub-adult U/K (1.96%) and juvenile (1.96%).

Population Size vs. Age structure and Seasonalmovement pattern of African Elephants (Loxodontaafricana, Blumenbach, 1797:Elephantidae) in Babile Elephant Sanctuary, Eastern Ethiopia

The focus of this paper is to study the population size and age structure of elephants, and their seasonal movement patterns in Babile Elephant Sanctuary (BES), Eastern Ethiopia. The study was carried out between May 2019 and April 2020. The population size of the elephant was estimated indirectly from the dung droppings using line-transect methods within a 42 km2 area; of which, each 12 km2 area in riverine and woodland, and 18 km2 in bushland habitats. The total estimate of the elephant population for the sanctuary was (230+20) or between (210 and 250). Besides, Elephant numbers were also estimated directly from sightings. The maximum number observed in a herd was 75. There was a declining trend for the past 49 years in the elephant population. The observed density for the whole sanctuary was 0.033 elephants per km2. In the elephant age structure, there were more intermediate (47%) and very few sub-adults (2.6%) size classes identified. The movement pattern of elephants was studied based on footprints, dung piles, and feeding signs The GPS recorded routes were marked on a geo-referenced map of the area using a GIS program (Arc map10.8). The result revealed that the present wet and dry seasonal movement patterns of elephants were noted following almost the Erer and Gobele valley routes in the oromia region of the sanctuary. Based on the study results, the following inference is drawn: identifying and documenting up-to-date information on population size and age structure, and seasonal movement of African elephants (i.e., the migratory routes and foraging areas for complete protection to maintain the animal's natural migratory patterns without disturbance) in BES is important to build gaps in knowledge for conservationists to design plans for restoring the species and sustaining the elephant’s existence. Therefore, strengthening the capacity of management and enforcing laws can minimize intimidation and enhance opportunities.

Physical and behavioral indicators associated with hormonal changes during musth in zoo-housed and free-ranging Asian elephants (Elephas maximus)

In-situ and ex-situ Asian elephant populations are threatened with extinction, and male elephants pose unique challenges to long-term sustainability. The heightened sexual state of “musth” is accompanied by a suite of physical, behavioral and physiological changes. Furthermore, musth is unique to male elephants and requires special consideration when developing short- and long-term management strategies for elephants in the wild and in human care. The purpose of this study was to identify associations between fecal hormone metabolites [fecal androgen metabolites, FAM; fecal glucocorticoid metabolites, FGM; and fecal triiodothyronine (T3) metabolites, FT3] and visible musth indicators [temporal gland secretions (TGS) and urine dribbling (UD)], and behavioral changes around musth. From fecal samples collected non-invasively from wild elephants in Wasgamuwa National Park, Sri Lanka, and zoo-housed elephants in the United States, we hypothesized that (1) TGS and/or UD would be associated with changes in FAM, FGM, and/or FT3 concentrations; (2) variation in fecal hormone metabolites would be associated with increased locomotion and chemosensory behavior, and decreased foraging; and (3) relationships we identified would be similar between wild and zoo-housed elephants. We found that FAM concentrations changed significantly with TGS and UD activity in both wild and zoo elephants. Further while FGM concentrations were higher with increased TGS and UD in zoo elephants, the opposite pattern occurred in wild elephants. We did not identify substantial change in FT3 concentrations with TGS/UD activity. Behavioral changes in zoo elephants were significantly associated with FAM concentration as predicted, but these relationships were more difficult to identify in wild elephants due to lower sample availability. Further, FGM concentration was directly related to time spent locomoting in zoo elephants, but no other apparent association existed between FGM concentration with other behaviors in zoo elephants, or in any behaviors in wild elephants. Likewise, we did not report associations between FT3 and any behaviors we measured. This study contributes to our understanding of the complex response patterns that male Asian elephants exhibit around musth, and it provides another example of complementary in-situ–ex-situ research that can be directly applied to improve the well-being of elephants and other wildlife.

元江-李仙江流域亚洲象生境适宜性评价——基于荟萃分析和遥感大数据分析

PDF HTML阅读 XML下载 导出引用 引用提醒 元江-李仙江流域亚洲象生境适宜性评价——基于荟萃分析和遥感大数据分析 DOI: 10.5846/stxb202106241680 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 第二次青藏高原综合科学考察研究（2019QZKK0402）；国家自然科学基金项目（41971239，41461017） Habitat suitability evaluation of Asian elephants in the Yuanjiang-Lixianjiang River Basin based on meta-analysis and remote sensing big data Author: Affiliation: Fund Project: The second comprehensive scientific expedition to the Qinghai-Tibet Plateau(2019QZKK0402);The National Natural Science Foundation of China(41971239，41461017) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:生境适宜性评价是物种保护和生境管理与规划的基础。近几十年来，云南境内野生亚洲象数量剧增，外扩迁移事件频发，而新迁入区域生境适宜状况因物种出现点数据缺乏而难以评价，掣肘迁移亚洲象保护与风险防范应急。以亚洲象新近迁入的元江-李仙江流域为案例区，采用荟萃分析统计亚洲象生境评价因子，结合相关性分析和方差膨胀因子独立性检验，筛选出生境评价因子；基于开源遥感数据产品量化生境因子，综合主成分分析和层次分析计算生境评价因子权重，采用生境适宜性指数（Habitat Suitability Index，HSI）模型评价元江-李仙江流域亚洲象生境适宜性，并分析其景观格局。结果表明：（1）元江-李仙江流域亚洲象生境适宜性空间格局主要表现为由下游至上游呈递减趋势，最适生境主要分布于流域下游段，而流域上游段适宜生境少；（2）元江流域生境适宜性低于李仙江流域，且其生境斑块连接度更低、破碎化更严重；（3）2021年"北移象群"北迁沿程生境适宜性由西南向东北呈下降趋势。基于亚洲象生境适宜性评价结果，科学引导野生亚洲象迁入适宜生境区，以规避人象冲突，保障外迁亚洲象群及其活动区居民生命财产安全，服务于区域生物多样性保护与乡村振兴。 Abstract:Habitat suitability evaluation is a basis for species conservation, habitat management and planning. Over the past decades, the number of wild Asian elephants in Yunnan Province of China has increased sharply, and elephants' emigration from their original habitats frequently occurred. However, habitat quality in the newly inhabited areas is often poorly known due to lack of records in presence of Asian elephants, which hinders Asian elephant protection and risk prevention. The rapid development of remote sensing big data mapping technology provides new data sources for habitat suitability evaluation studies, and offers the possibility of identifying suitable habitats for species on a large regional scale more accurately and finely. In this study, a remote sensing big data-driven habitat suitability evaluation system for Asian elephants is constructed. We selected the Yuanjiang-Lixianjiang River Basin newly immigrated by Asian elephants as a case area, used meta-analysis to search for environmental factors related to Asian elephants habitat evaluation, and screened out habitat suitability evaluation factors by combining correlation analysis with variance inflation factor test. Subsequently, all habitat suitability evaluation factors were quantified based on open-source remote sensing data products and their weights were calculated using principal component analysis and analytic hierarchy process. Finally, we used a Habitat Suitability Index (HSI) model to determine the habitat suitability of Asian elephants in the study area and analyzed landscape patterns of habitats of Asian elephants. The results show that (1) the habitat suitability of Asian elephants in the Yuanjiang-Lixian River Basin decreased gradually upstream. The optimal habitat mainly occurred in the downstream basin, with a small distribution in the midstream basin and almost no distribution in the upstream basin. (2) The Yuanjiang River Basin was less suitable for Asian elephants than the Lixian River Basin because it had less connected and more fragmented habitat patches, which cannot meet the minimum home range requirements of Asian elephant populations and make it difficult to sustain a long-term survival of the "northward migration elephant herd". (3) The habitat suitability decreased along the northward migration route of elephant herd called "northward migration elephant herd" roaming in 2021 with the decreased distribution of natural broad-leaved forests along the way. The findings provide a basis for scientifically guiding the elephant herd into suitable habitats to avoid the conflicts between the human and wild elephant and thereby to ensure the safety of the elephant herd and the affected residents, which will serve for the regional biodiversity conservation and rural revitalization. 参考文献 相似文献 引证文献

Proboscideans on Parade: A review of the migratory behaviour of elephants, mammoths, and mastodons

The ecology and behaviour of woolly and Columbian mammoths and mastodons have been extensively studied. Despite this, their patterns of mobility, and particularly the question of whether or not they migrated habitually, remains unclear. This paper summarises the current state of knowledge regarding mobility in these species, reviewing comparative datasets from extant elephant populations as well as isotopic data measured directly on the ancient animals themselves.Seasonal migration is not common in modern elephants and varies between years. Nonetheless, non-migratory elephants can still have considerable home ranges, whose size is affected mainly by habitat, seasonal availability of water and food, and biological sex. Strontium isotope analyses of woolly mammoths, Columbian mammoths, and mastodons demonstrate plasticity in their migratory behaviour as well, probably in response to spatio-temporal variations in ecological conditions. However, biological sex is difficult to establish for most proboscidean fossils and its influence on the results of Sr analyses can therefore not be assessed. Advances in intra-tooth sampling and analytical methods for strontium isotope analysis have enabled research on intra-annual movement, revealing nomadic behaviour in all three species. Sulfur isotopes have been analysed from woolly mammoth remains numerous times, but its methodology is not yet developed well enough to inform on past proboscidean mobility in as much detail as strontium studies.The inter- and intra-individual variation in migratory behaviour in mammoths and mastodons implies that their role in the subsistence strategies of Palaeolithic people may have fluctuated as well. Further assessment of hominin-proboscidean predator-prey interactions will require a more detailed understanding of proboscidean habitual mobility in specific contexts and places. Strontium isotope studies based on multi-year enamel sequences from multiple individuals have the potential to provide this insight.

Human-Elephant interactions and associated damage in the northern transboundary areas of Bangladesh

We have studied human-elephant interactions in the northern transboundary of Bangladesh and estimated the scale of associated damage due to the negative interaction by visiting conflict area, performing focus group discussions key informant interviews and using secondary data sources. Around 70-80 non-resident elephants regularly intruded to the study area through the international border fence using several trespassing points and engaged in conflicts with frontier villagers. We discussed the nature and scale of conflict and the financial losses due to the conflict. Besides severe casualties in both ends, the enumerated economic loss was USD 1,171, 665 in 2013 and 2014 due to the damage to cropland, houses and properties, trees and orchards. We have identified major human-elephant conflict (HEC) zones adjacent to the border fence through spatial analysis with different level of intensity. Appropriate human-elephant conflict mitigation measures such as habitat improvement and management, monitoring of elephant population, alternative income generation, awareness programs for the local people and working together with India regarding this issue is a timely and urgent need for Bangladesh

Elephant Population Status, Distribution and Conservation Threats in Kibale National Park, Uganda

This study focused on the estimation of the African elephant population, distribution, and conservation threats in Kibale National Park (KNP) from August 2019 to February 2020. The objectives of the study were to: generate population estimates, distribution and assess threats to the conservation of elephants. The line transect method based on the dung pile count density from line transect, dung decay, and defecation rates were used to estimate the elephant population. The density was calculated by multiplying the decay rate with the ratio of dung density to defecation rates. The overall elephant population was estimated at 566.27 (95% Confidence limits 377.24-850.02). This was a slow increase from 393 recorded in 2005 to 566 animals in 2019. Elephants were widely distributed within the park and these pose challenges such as increasing human-elephant conflicts. With a steady increase in the elephant population and seasonal movements out of the park, there is a need to continuously monitor elephant population growth and ranging behaviour vis-a-vis available habitat range and how this impacts ecosystem dynamics and human-elephant conflicts

Pan-India population genetics signifies the importance of habitat connectivity for wild Asian elephant conservation

Asian elephants are endangered while they have faced ~70% population decline in India in the last 60 years. Climate change projections indicate exacerbation of ongoing habitat loss (>40%) by 2070, potentially impacting genetic structure of wild elephants across India. Therefore, we provide consolidated baseline data on genetic diversity and structure of elephants across four eco-regions of India, i.e., north-western (NW), north-eastern (NE), east-central (ECI), and southern India (SI), to identify populations at greater risk of further divergence. We genotyped 169 faecal samples across 14 microsatellites with 90.0% overall success rate. The genetic diversity levels were moderate and varied between the eco-regions (HE =0.57–0.74). Allelic richness was higher in NE (3.73–3.78) and SI (3.62–3.71). We observed a high inbreeding coefficient in NE (FIS=0.55–0.58) compared to the other elephant populations, probably due to the presence of related individuals in our samples. Genetic differentiation between populations using FST statistics (FST=0.06–0.18) was significant. Bayesian and multivariate analyses identified three major genetic clusters in India – NW, NE, and combined ECI-SI, mostly consistent with their geographic distribution. We also observed an unexpected pattern of high genetic distance between adjacent populations. This fine-scale genetic structure suggests the presence of barriers (natural and anthropogenic) and complex social organisation. Additionally, incipient sub-structuring within NE and SI indicates potential genetic discontinuity. These results highlight the importance of maintaining genetic diversity, particularly of NE and ECI populations, by retaining habitat connectivity and ensuring gene flow for effective elephant conservation in India.

Illegal settlement in the Babile Elephant Sanctuary is threatening the resident elephant population

AbstractThe Babile Elephant Sanctuary in Ethiopia was established in 1970 specifically to protect its elephants Loxodonta africana. They were once part of a larger population that ranged in eastern Ethiopia and northern Somalia but that was largely extirpated during the 20th century. Since its establishment, the Sanctuary has experienced severe anthropogenic pressure, inadequate government support, and civil conflict. Mapping was undertaken to analyse the rate of human immigration into the Sanctuary in 2006, 2014 and 2017, as part of an assessment of the Sanctuary's effectiveness in protecting its resident elephant population and in mitigating anthropogenic pressures. From 2006 to 2017 the number of illegal houses in the Sanctuary increased from 18,000 to &gt; 50,000, of which &gt; 32,000 were in the area in which elephants range. This settlement, coupled with high demand for natural resources, has resulted in significant habitat destruction and could also have exacerbated human–elephant conflict. Elephant conservation and monitoring by the Born Free Foundation were challenging because of ethnic conflict; rural and political stability is required if efforts to protect wildlife are to be successful. Unless these issues are resolved and the integrity of the Sanctuary is restored, this elephant population will be extirpated in the near future.