1
|
LaDue CA, Davis M, Emory R, Snyder RJ. Male elephant management in AZA institutions: Current status and priorities for the future. Zoo Biol 2024. [PMID: 38698564 DOI: 10.1002/zoo.21835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 01/13/2024] [Accepted: 04/09/2024] [Indexed: 05/05/2024]
Abstract
Asian elephant (Elephas maximus) and African savanna elephant (Loxodonta africana) populations collectively managed by ex-situ facilities accredited by the Association of Zoos and Aquariums (AZA) face sustainability challenges. Among the priorities to strengthen animal wellbeing and population sustainability is male elephant management. We conducted a survey of AZA facilities currently housing male elephants to assess the status, challenges, and priorities in three areas of male elephant management: musth, socialization, and semen collection. Surveys were administered to elephant care teams at AZA-accredited institutions between November 2022 and February 2023, and we received responses from 34 institutions (91.9% of AZA-accredited facilities holding adult male elephants), housing 32 adult male Asians and 26 adult male Africans. Most facilities prioritized breeding and male socialization over musth management and semen collection (although most facilities acknowledged that all these efforts are important), citing leadership support and staffing as most important to achieve male management goals. Behaviors most commonly accompanying musth included reduced appetite, difficulty training or shifting, human-directed aggression, and interest in females. Musth timing was variable between males and facilities. Most males were well-socialized with females and/or other males, though elephant compatibility and facility design were limiting factors in managing socialization. Although 60.6% of facilities collected semen or were training for semen collection, very few male elephants could reliably provide viable semen samples, challenging assisted reproductive efforts that could bolster population sustainability in both species. Together, our results provide a better understanding of the state of male elephant management, offering specific areas deserving of research and development to enhance wellbeing and sustainability.
Collapse
Affiliation(s)
- Chase A LaDue
- Oklahoma City Zoo and Botanical Garden, Oklahoma City, Oklahoma, USA
| | | | - Rachel Emory
- Oklahoma City Zoo and Botanical Garden, Oklahoma City, Oklahoma, USA
| | - Rebecca J Snyder
- Oklahoma City Zoo and Botanical Garden, Oklahoma City, Oklahoma, USA
| |
Collapse
|
2
|
Gautam H, Vidya TNC. Do food distribution and competitor density affect agonistic behaviour within and between clans in a high fission-fusion species? ROYAL SOCIETY OPEN SCIENCE 2023; 10:230990. [PMID: 38077213 PMCID: PMC10698478 DOI: 10.1098/rsos.230990] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 11/13/2023] [Indexed: 01/11/2024]
Abstract
According to the ecological model of female social relationships (EMFSR), within-group competition and between-group competition in female-bonded species are shaped by food distribution. Strong between-group contests are expected over large, monopolizable resources and high population density, but not when low-quality food is distributed across large, undefended home ranges. Within-group contests are expected to be more frequent with increasing heterogeneity among feeding sites and with group size. We tested these predictions in female Asian elephants, which show traits associated with infrequent contests-graminivory, high fission-fusion and overlapping home ranges. We examined how food distribution and competitor density affected agonistic interactions within and between female elephant clans (social groupings) in the Kabini grassland, southern India. We found stronger between-clan contest in the grassland than that known from neighbouring forests, and more frequent agonism between females between clans than within clans. Such strong between-clan contest was attributable to the grassland being a food-rich habitat patch, thus supporting the EMFSR. Within-clan agonism was also frequent, but did not increase with food heterogeneity, contradicting the EMFSR. Contrary to recent claims, increasing within-clan agonism with group size suggested ecological constraints on large groups despite high fission-fusion. High population density may explain such frequent contests despite graminivory and fission-fusion.
Collapse
Affiliation(s)
- Hansraj Gautam
- Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru, India
| | - T. N. C. Vidya
- Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru, India
| |
Collapse
|
3
|
Sooriyabandara MGC, Jayasundara JMSM, Marasinghe MSLRP, Hathurusinghe HABM, Bandaranayake AU, Jayawardane KANC, Nilanthi RMR, Rajapakse RC, Bandaranayake PCG. Genetic features of Sri Lankan elephant, Elephas maximus maximus Linnaeus revealed by high throughput sequencing of mitogenome and ddRAD-seq. PLoS One 2023; 18:e0285572. [PMID: 37310948 DOI: 10.1371/journal.pone.0285572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 04/26/2023] [Indexed: 06/15/2023] Open
Abstract
Elephas maximus maximus Linnaeus, the Sri Lankan subspecies is the largest and the darkest among Asian elephants. Patches of depigmented areas with no skin color on the ears, face, trunk, and belly morphologically differentiate it from the others. The elephant population in Sri Lanka is now limited to smaller areas and protected under Sri Lankan law. Despite its ecological and evolutionary importance, the relationship between Sri Lankan elephants and their phylogenetic position among Asian elephants remains controversial. While identifying genetic diversity is the key to any conservation and management strategies, limited data is currently available. To address such issues, we analyzed 24 elephants with known parental lineages with high throughput ddRAD-seq. The mitogenome suggested the coalescence time of the Sri Lankan elephant at ~0.2 million years, and sister to Myanmar elephants supporting the hypothesis of the movement of elephants in Eurasia. The ddRAD-seq approach identified 50,490 genome-wide SNPs among Sri Lankan elephants. The genetic diversity within Sri Lankan elephants assessed with identified SNPs suggests a geographical differentiation resulting in three main clusters; north-eastern, mid-latitude, and southern regions. Interestingly, though it was believed that elephants from the Sinharaja rainforest are of an isolated population, the ddRAD-based genetic analysis clustered it with the north-eastern elephants. The effect of habitat fragmentation on genetic diversity could be further assessed with more samples with specific SNPs identified in the current study.
Collapse
Affiliation(s)
| | - J M S M Jayasundara
- Agricultural Biotechnology Centre, Faculty of Agriculture, University of Peradeniya, Peradeniya, Sri Lanka
| | | | - H A B M Hathurusinghe
- Agricultural Biotechnology Centre, Faculty of Agriculture, University of Peradeniya, Peradeniya, Sri Lanka
| | - A U Bandaranayake
- Department of Computer Engineering, Faculty of Engineering, University of Peradeniya, Peradeniya, Sri Lanka
| | | | - R M R Nilanthi
- Department of Wildlife Conservation, Battaramulla, Sri Lanka
| | - R C Rajapakse
- Department of National Zoological Gardens, Anagarika Dharmapala Mawatha, Dehiwala, Sri Lanka
| | - P C G Bandaranayake
- Agricultural Biotechnology Centre, Faculty of Agriculture, University of Peradeniya, Peradeniya, Sri Lanka
| |
Collapse
|
4
|
Montero-De La Torre S, Jacobson SL, Chodorow M, Yindee M, Plotnik JM. Day and night camera trap videos are effective for identifying individual wild Asian elephants. PeerJ 2023; 11:e15130. [PMID: 37009152 PMCID: PMC10064994 DOI: 10.7717/peerj.15130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 03/06/2023] [Indexed: 03/30/2023] Open
Abstract
Regular monitoring of wild animal populations through the collection of behavioral and demographic data is critical for the conservation of endangered species. Identifying individual Asian elephants (Elephas maximus), for example, can contribute to our understanding of their social dynamics and foraging behavior, as well as to human-elephant conflict mitigation strategies that account for the behavior of specific individuals involved in the conflict. Wild elephants can be distinguished using a variety of different morphological traits—e.g., variations in ear and tail morphology, body scars and tumors, and tusk presence, shape, and length—with previous studies identifying elephants via direct observation or photographs taken from vehicles. When elephants live in dense forests like in Thailand, remote sensing photography can be a productive approach to capturing anatomical and behavioral information about local elephant populations. While camera trapping has been used previously to identify elephants, here we present a detailed methodology for systematic, experimenter differentiation of individual elephants using data captured from remote sensing video camera traps. In this study, we used day and night video footage collected remotely in the Salakpra Wildlife Sanctuary in Thailand and identified 24 morphological characteristics that can be used to recognize individual elephants. A total of 34 camera traps were installed within the sanctuary as well as crop fields along its periphery, and 107 Asian elephants were identified: 72 adults, 11 sub-adults, 20 juveniles, and four infants. We predicted that camera traps would provide enough information such that classified morphological traits would aid in reliably identifying the adult individuals with a low probability of misidentification. The results indicated that there were low probabilities of misidentification between adult elephants in the population using camera traps, similar to probabilities obtained by other researchers using handheld cameras. This study suggests that the use of day and night video camera trapping can be an important tool for the long-term monitoring of wild Asian elephant behavior, especially in habitats where direct observations may be difficult.
Collapse
Affiliation(s)
- Sasha Montero-De La Torre
- Department of Psychology, Hunter College, City University of New York, New York, New York, United States
| | - Sarah L. Jacobson
- Department of Psychology, Hunter College, City University of New York, New York, New York, United States
- Department of Psychology, The Graduate Center, City University of New York, New York, New York, United States
| | - Martin Chodorow
- Department of Psychology, Hunter College, City University of New York, New York, New York, United States
- Department of Psychology, The Graduate Center, City University of New York, New York, New York, United States
| | - Marnoch Yindee
- Akkhraratchakumari Veterinary College and One Health Research Centre, Walailak University, Thasala, Nakhon Si Thammarat, Thailand
| | - Joshua M. Plotnik
- Department of Psychology, Hunter College, City University of New York, New York, New York, United States
- Department of Psychology, The Graduate Center, City University of New York, New York, New York, United States
| |
Collapse
|
5
|
Hoornweg TE, Perera VP, Karunarathne RN, Schaftenaar W, Mahakapuge TA, Kalupahana AW, Rutten VP, de Haan CA. Young elephants in a large herd maintain high levels of elephant endotheliotropic herpesvirus-specific antibodies and do not succumb to fatal haemorrhagic disease. Transbound Emerg Dis 2022; 69:e3379-e3385. [PMID: 35757981 PMCID: PMC9796006 DOI: 10.1111/tbed.14644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 06/23/2022] [Accepted: 06/24/2022] [Indexed: 12/30/2022]
Abstract
Elephant endotheliotropic herpesviruses (EEHVs) have co-existed with elephants for millions of years, yet may cause fatal haemorrhagic disease (EEHV-HD), typically in elephants between 1 and 10 years of age. EEHV is omnipresent in (sub)adult elephants, and young elephants with low EEHV-specific antibody levels are at risk for EEHV-HD, suggesting that fatal disease may occur due to an insufficiently controlled primary infection. To further address this hypothesis, sera of three large elephant cohorts were subjected to a multiple EEHV species ELISA: (I) 96 Asian elephants between 0 and 57 years, including 13 EEHV-HD fatalities, from European zoo herds typically sized five to six elephants, (II) a herd of 64 orphaned elephants aged 0-15 years at the Elephant Transit Home in Sri Lanka and (III) 31 elephants aged 8-63 years, part of a large herd of 93 elephants at Pinnawala Elephant Orphanage, Sri Lanka. All Sri Lankan elephants showed high EEHV-specific antibody levels regardless of their age. While antibody levels of most European zoo elephants were comparable to those of Sri Lankan elephants, the average antibody level of the European juveniles (1-5 years of age) was significantly lower than those of age-matched Sri Lankan individuals. Moreover, the European juveniles showed a gradual decrease between 1 and 4 years of age, to be attributed to waning maternal antibodies. Maintenance of high levels of antibodies in spite of waning maternal antibodies in young Sri Lankan elephants is likely due to the larger herd size that increases the likelihood of contact with EEHV-shedding elephants. Together with the observation that low levels of EEHV-specific antibodies correlate with increased numbers of EEHV-HD fatalities, these results suggest that infection in presence of high maternal antibody levels may protect calves from developing EEHV-HD, while at the same time activating an immune response protective in future encounters with this virus.
Collapse
Affiliation(s)
- Tabitha E. Hoornweg
- Section of VirologyDivision Infectious Diseases and ImmunologyFaculty of Veterinary MedicineDepartment of Biomolecular Health SciencesUtrecht UniversityUtrechtThe Netherlands,Section of ImmunologyDivision Infectious Diseases and ImmunologyFaculty of Veterinary MedicineDepartment of Biomolecular Health SciencesUtrecht UniversityUtrechtThe Netherlands
| | - Vijitha P. Perera
- Department of Wildlife Conservation, Elephant Transit HomeUdawalaweSri Lanka
| | | | - Willem Schaftenaar
- Veterinary Advisor EAZA Elephant TAGRotterdam ZooRotterdamThe Netherlands
| | - Thilini A.N. Mahakapuge
- Faculty of Veterinary Medicine and Animal ScienceDepartment of Veterinary PathobiologyUniversity of PeradeniyaPeradeniyaSri Lanka
| | - Anil. W. Kalupahana
- Faculty of Veterinary Medicine and Animal ScienceDepartment of Veterinary PathobiologyUniversity of PeradeniyaPeradeniyaSri Lanka
| | - Victor P.M.G. Rutten
- Section of ImmunologyDivision Infectious Diseases and ImmunologyFaculty of Veterinary MedicineDepartment of Biomolecular Health SciencesUtrecht UniversityUtrechtThe Netherlands,Faculty of Veterinary ScienceDepartment of Veterinary Tropical DiseasesUniversity of PretoriaOnderstepoortSouth Africa
| | - Cornelis A.M. de Haan
- Section of VirologyDivision Infectious Diseases and ImmunologyFaculty of Veterinary MedicineDepartment of Biomolecular Health SciencesUtrecht UniversityUtrechtThe Netherlands
| |
Collapse
|
6
|
Fuchs E, Beeck VC, Baotic A, Stoeger AS. Acoustic structure and information content of trumpets in female Asian elephants (Elephas maximus). PLoS One 2021; 16:e0260284. [PMID: 34813615 PMCID: PMC8610244 DOI: 10.1371/journal.pone.0260284] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 11/05/2021] [Indexed: 12/02/2022] Open
Abstract
Most studies on elephant vocal communication have focused on the low-frequency rumble, with less effort on other vocalization types such as the most characteristic elephant call, the trumpet. Yet, a better and more complete understanding of the elephant vocal system requires investigating other vocalization types and their functioning in more detail as well. We recorded adult female Asian elephants (Elephas maximus) at a private facility in Nepal and analyzed 206 trumpets from six individuals regarding their frequency, temporal and contour shape, and related acoustic parameters of the fundamental frequency. We also tested for information content regarding individuality and context. Finally, we recorded the occurrence of non-linear phenomena such as bifurcation, biphonation, subharmonics and deterministic chaos. We documented a mean fundamental frequency ± SD of 474 ± 70 Hz and a mean duration ± SD of 1.38 ± 1.46 s (Nindiv. = 6, Ncalls = 206). Our study reveals that the contour of the fundamental frequency of trumpets encodes information about individuality, but we found no evidence for trumpet subtypes in greeting versus disturbance contexts. Non-linear phenomena prevailed and varied in abundance among individuals, suggesting that irregularities in trumpets might enhance the potential for individual recognition. We propose that trumpets in adult female Asian elephants serve to convey an individual's identity as well as to signal arousal and excitement to conspecifics.
Collapse
Affiliation(s)
- Evelyn Fuchs
- Mammal Communication Lab, Department of Behavioral and Cognitive Biology, University of Vienna, Vienna, Austria
| | - Veronika C. Beeck
- Mammal Communication Lab, Department of Behavioral and Cognitive Biology, University of Vienna, Vienna, Austria
| | - Anton Baotic
- Mammal Communication Lab, Department of Behavioral and Cognitive Biology, University of Vienna, Vienna, Austria
| | - Angela S. Stoeger
- Mammal Communication Lab, Department of Behavioral and Cognitive Biology, University of Vienna, Vienna, Austria
| |
Collapse
|
7
|
Thevarajah SJ, Readyhough TS, Davis M, Moresco A, Joseph S, Schreier AL. Nighttime behavior and the length of social relationships in male Asian elephants. J APPL ANIM WELF SCI 2021:1-16. [PMID: 34761998 DOI: 10.1080/10888705.2021.1998777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
To evaluate elephant welfare, it is important to understand their use of time both during day and night. The length of social relationships can influence how much time they spend in different activities. We assessed daytime and nighttime activity budgets of male Asian elephants at Denver Zoo and examined how length of relationships influenced nighttime behavior. Using scan sampling we investigated activity budget and proximity to a conspecific, and used General Estimating Equations to compare them across day and night and across new and established dyads at night. During daytime, elephants spent significantly more time exhibiting affiliative and agonistic behaviors, and in proximity to a conspecific, and less time resting, compared to night. Overnight, the odds of resting were significantly lower in new social dyads compared to established dyads, and new dyads spent more time exhibiting agonistic behavior and in proximity to a conspecific compared to established dyads. Our study suggests that male elephants at Denver Zoo have developed strong relationships and highlights the importance of systematically observing elephants overnight so that managers make decisions that improve animal welfare.
Collapse
Affiliation(s)
| | - Taylor S Readyhough
- Department of Biology, Regis University, CO, USA.,Department of Animal Wellness and Research, Denver Zoo, CO, USA
| | - Maura Davis
- Department of Animal Care, Denver Zoo, CO, USA
| | - Anneke Moresco
- Department of Animal Wellness and Research, Denver Zoo, CO, USA.,Reproductive Health Surveillance Program, Morrison, CO
| | - Sharon Joseph
- Department of Animal Wellness and Research, Denver Zoo, CO, USA.,Birmingham Zoo, Birmingham, AL
| | - Amy L Schreier
- Department of Biology, Regis University, CO, USA.,Department of Animal Wellness and Research, Denver Zoo, CO, USA
| |
Collapse
|
8
|
LaDue CA, Schulte BA, Kiso WK, Freeman EW. Musth and sexual selection in elephants: a review of signalling properties and potential fitness consequences. BEHAVIOUR 2021. [DOI: 10.1163/1568539x-bja10120] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Sexual selection mediated by multimodal signals is common among polygynous species, including seasonally breeding mammals. Indirect benefit models provide plausible explanations for how and why mate selection can occur in the absence of direct benefits. Musth — an asynchronous reproductive state in male elephants — facilitates both inter- and intrasexual selection via indirect benefits, and it is further communicated through a multimodal signal. In this review, we synthesise existing evidence that supports the hypothesis that musth is a multimodal signal subject to sexual selection and that male elephants increase their direct fitness by propagating this signal while females accrue indirect benefits. Musth is characterised by a suite of physiological and behavioural changes, serving to facilitate copulation between the sexes, and via multisensory modalities musth conveys honest information about the condition of a male. Female elephants mate preferentially with musth males, increasing their own fitness in the absence of direct benefits. In addition, musth resolves dynamic dominance hierarchies among male elephants and often eliminates the need for costly physical combat. Future work in this field should investigate potential postcopulatory selection mechanisms in elephants, including sperm competition and cryptic female choice. These topics join other fundamental questions related to sexual selection, signalling, and indirect benefits that are still unanswered in elephants.
Collapse
Affiliation(s)
- Chase A. LaDue
- Department of Environmental Science and Policy, George Mason University, Fairfax, VA, USA
| | - Bruce A. Schulte
- Department of Biology, Western Kentucky University, Bowling Green, KY, USA
| | | | | |
Collapse
|
9
|
Athira TK, Vidya TNC. Elephant Social Systems: What Do We Know and How Have Molecular Tools Helped? J Indian Inst Sci 2021. [DOI: 10.1007/s41745-021-00226-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
10
|
Aznar-Cormano L, Bonnald J, Krief S, Guma N, Debruyne R. Molecular sexing of degraded DNA from elephants and mammoths: a genotyping assay relevant both to conservation biology and to paleogenetics. Sci Rep 2021; 11:7227. [PMID: 33790303 PMCID: PMC8012363 DOI: 10.1038/s41598-021-86010-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 01/29/2021] [Indexed: 11/24/2022] Open
Abstract
It is important to determine the sex of elephants from their samples-faeces from the field or seized ivory-for forensic reasons or to understand population demography and genetic structure. Molecular sexing methods developed in the last two decades have often shown limited efficiency, particularly in terms of sensitivity and specificity, due to the degradation of DNA in these samples. These limitations have also prevented their use with ancient DNA samples of elephants or mammoths. Here we propose a novel TaqMan-MGB qPCR assay to address these difficulties. We designed it specifically to allow the characterization of the genetic sex for highly degraded samples of all elephantine taxa (elephants and mammoths). In vitro experiments demonstrated a high level of sensitivity and low contamination risks. We applied this assay in two actual case studies where it consistently recovered the right genotype for specimens of known sex a priori. In the context of a modern conservation survey of African elephants, it allowed determining the sex for over 99% of fecal samples. In a paleogenetic analysis of woolly mammoths, it produced a robust hypothesis of the sex for over 65% of the specimens out of three PCR replicates. This simple, rapid, and cost-effective procedure makes it readily applicable to large sample sizes.
Collapse
Affiliation(s)
- Laetitia Aznar-Cormano
- CNRS, Centre de Recherche en Paléontologie Paris (CR2P), Muséum national d'Histoire naturelle, Sorbonne Université, 57 rue Cuvier, CP 38, 75005, Paris, France
| | - Julie Bonnald
- CNRS, Eco-Anthropologie (EA), Muséum national d'Histoire naturelle, Université Paris Diderot, 17 place du Trocadéro, 75016, Paris, France
- Sebitoli Chimpanzee Project, Sebitoli Research Station, Kibale National Park, Fort Portal, Uganda
| | - Sabrina Krief
- CNRS, Eco-Anthropologie (EA), Muséum national d'Histoire naturelle, Université Paris Diderot, 17 place du Trocadéro, 75016, Paris, France
- Sebitoli Chimpanzee Project, Sebitoli Research Station, Kibale National Park, Fort Portal, Uganda
| | | | - Régis Debruyne
- Direction Générale Déléguée à la Recherche, à l'Expertise, la Valorisation et l'Enseignement (DGD-REVE), Muséum national d'Histoire naturelle, 57 rue Cuvier, CP 17, 75005, Paris, France.
| |
Collapse
|
11
|
Abstract
AbstractWe studied garbage consumption by Asian elephants at the Uddakandara garbage dump in southern Sri Lanka. Garbage at the dump was classified under six categories and quantified using a grid overlay. Elephants visiting the dump were individually identified by morphological criteria and items and quantities consumed by them were determined by focal animal sampling. Dung of elephants that did not consume garbage and those from the dump were compared quantitatively and dung constituents assessed by washing through three layered sieves. A total of 17 individual elephants visited the garbage dump during the study period, all of who were males. The observed sexual bias could be related to behavioural differences between the sexes. Elephants mostly consumed ‘fruits and vegetables’ and ‘prepared food’, possibly due to their higher palatability and nutritional value. Ingestion of polythene was incidental and associated with consuming prepared food. Proportions of the six categories in elephant diet and garbage piles were significantly different, indicating that elephants were highly selective when feeding. Elephant arrivals increased in response to unloading of garbage, suggesting attraction to fresh garbage. Dung analysis found that garbage consumption did not change the quantity and constituents of dung, except for the presence of anthropogenic items. As consumed anthropogenic items were regularly excreted, retention and obstruction of the alimentary tract are unlikely in elephants. Elephants feeding on garbage had better body condition than non-garbage consuming elephants, indicating that garbage provided better nutrition than natural food and was not detrimental to their health.
Collapse
|
12
|
Abstract
AbstractFeeding of wild Asian elephants at the Udawalawe National Park perimeter electric fence by the general public is longstanding. We monitored the elephants and feeding activities, and conducted questionnaire surveys of stakeholders. Over 50 individual adult male elephants engaged in the activity. The exclusive male presence was consistent with a high-risk high-gain male strategy. The elephants were mostly offered fruits and vegetables. Over a thousand people a day watched and fed the elephants. Most people bought food for elephants from roadside stalls and vendors had significantly more sales if elephants were present. The feeding of elephants brought significant economic benefit to communities bordering the park. We found the impacts of feeding on the elephants and environment to be largely neutral. Impacts on people and conservation were mainly positive. Actions taken by authorities to stop the feeding have targeted the elephants and resulted in the decrease of feeding but not its elimination. Managing the activity instead would help increase economic benefits and ensure safe interaction between people and elephants. Such management, by directly benefitting local communities, could make them partners in the conservation process and form the basis of an effective outreach program.
Collapse
|
13
|
Lohay GG, Weathers TC, Estes AB, McGrath BC, Cavener DR. Genetic connectivity and population structure of African savanna elephants ( Loxodonta africana) in Tanzania. Ecol Evol 2020; 10:11069-11089. [PMID: 33144949 PMCID: PMC7593188 DOI: 10.1002/ece3.6728] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 07/27/2020] [Accepted: 08/06/2020] [Indexed: 11/07/2022] Open
Abstract
Increasing human population growth, exurban development, and associated habitat fragmentation is accelerating the isolation of many natural areas and wildlife populations across the planet. In Tanzania, rapid and ongoing habitat conversion to agriculture has severed many of the country's former wildlife corridors between protected areas. To identify historically linked protected areas, we investigated the genetic structure and gene flow of African savanna elephants in Tanzania using microsatellite and mitochondrial DNA markers in 688 individuals sampled in 2015 and 2017. Our results indicate distinct population genetic structure within and between ecosystems across Tanzania, and reveal important priority areas for connectivity conservation. In northern Tanzania, elephants sampled from the Tarangire-Manyara ecosystem appear marginally, yet significantly isolated from elephants sampled from the greater Serengeti ecosystem (mean F ST = 0.03), where two distinct subpopulations were identified.Unexpectedly, elephants in the Lake Manyara region appear to be more closely related to those across the East African Rift wall in the Ngorongoro Conservation Area than they are to the neighboring Tarangire subpopulations. We concluded that the Rift wall has had a negligible influence on genetic differentiation up to this point, but differentiation may accelerate in the future because of ongoing loss of corridors in the area. Interestingly, relatively high genetic similarity was found between elephants in Tarangire and Ruaha although they are separated by >400 km. In southern Tanzania, there was little evidence of female-mediated gene flow between Ruaha and Selous, probably due to the presence of the Udzungwa Mountains between them. Despite observing evidence of significant isolation, the populations of elephants we examined generally exhibited robust levels of allelic richness (mean A R = 9.96), heterozygosity (mean µH E = 0.73), and effective population sizes (mean N e = 148). Our results may inform efforts to restore wildlife corridors between protected areas in Tanzania in order to facilitate gene flow for long-term survival of elephants and other species.
Collapse
Affiliation(s)
- George G. Lohay
- Biology DepartmentThe Pennsylvania State UniversityUniversity ParkPAUSA
| | - Thomas Casey Weathers
- Ecosystem Science and ManagementThe Pennsylvania State UniversityUniversity ParkPAUSA
| | - Anna B. Estes
- Environmental Studies DepartmentCarleton CollegeNorthfieldMNUSA
- The Nelson Mandela African Institution of Science and TechnologyArushaTanzania
| | | | - Douglas R. Cavener
- Biology DepartmentThe Pennsylvania State UniversityUniversity ParkPAUSA
- The Nelson Mandela African Institution of Science and TechnologyArushaTanzania
| |
Collapse
|
14
|
He C, DU J, Zhu D, Zhang L. Population viability analysis of small population: a case study for Asian elephant in China. Integr Zool 2020; 15:350-362. [PMID: 32246885 DOI: 10.1111/1749-4877.12432] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Small populations are at risk of extinction from deterministic and stochastic factors. Less than 250 Asian elephants (Elephas maximus) remain in China, and are distributed in a few isolated areas; yet, population viability analyses of this endangered population have not been conducted. Here, the current genetic status of the Pu'Er-Mengyang Asian elephant populations in China was analyzed, and the risk of extinction was predicted over the next 500 years. Factors affecting the viability of this population were determined through simulations. The genetic diversity of the population was very low (mean allele number: 3.1; expected heterozygosity: 0.463), even though a recent population bottleneck was not detected. The effective population size was approximately 24.1 adult elephants. Enough adult breeding individuals exist to maintain population viability. VORTEX simulation model showed that this population would not go extinct in the next 500 years. However, illegal poaching and harvesting could negatively affect population size. A sensitivity analysis showed that the mean stochastic growth rate of the study population is sensitive to sex ratio, number of breeding females, mortality of females of different age classes, carrying capacity, and lethal equivalents. Based on our results, we suggest that action should be taken to alleviate inbreeding and any further loss of genetic diversity, by connecting fragmented elephant habitat or by translocating individual elephants. In addition, human-elephant conflict should be mitigated using various modern approaches, including crop guarding techniques, and by encouraging farmers to switch to crops and income sources not vulnerable to elephant raids.
Collapse
Affiliation(s)
- Changhuan He
- College of Life Sciences, Beijing Normal University, Beijing, China
| | - Jiaojiao DU
- College of Life Sciences, Beijing Normal University, Beijing, China
| | - Di Zhu
- College of Life Sciences, Beijing Normal University, Beijing, China
| | - Li Zhang
- College of Life Sciences, Beijing Normal University, Beijing, China
| |
Collapse
|
15
|
Social structure and demography of a remnant Asian elephant Elephas maximus population and the implications for survival. ORYX 2020. [DOI: 10.1017/s0030605319000504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
AbstractThe Asian elephant Elephas maximus is at risk of extinction as a result of anthropogenic pressures, and remaining populations are often small and fragmented remnants, occupying a fraction of the species' former range. Once widely distributed across China, only a maximum of 245 elephants are estimated to survive across seven small populations. We assessed the Asian elephant population in Nangunhe National Nature Reserve in Lincang Prefecture, China, using camera traps during May–July 2017, to estimate the population size and structure of this genetically important population. Although detection probability was low (0.31), we estimated a total population size of c. 20 individuals, and an effective density of 0.39 elephants per km2. Social structure indicated a strong sex ratio bias towards females, with only one adult male detected within the population. Most of the elephants associated as one herd but three adult females remained separate from the herd throughout the trapping period. These results highlight the fragility of remnant elephant populations such as Nangunhe and we suggest options such as a managed metapopulation approach for their continued survival in China and more widely.
Collapse
|
16
|
Menon V, Tiwari SKR. Population status of Asian elephants
Elephas maximus
and key threats. ACTA ACUST UNITED AC 2019. [DOI: 10.1111/izy.12247] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- V. Menon
- Founder, CEO and Executive Director Wildlife Trust of India; Chair, IUCN SSC Asian Elephant Specialist Group Noida Uttar Pradesh 201301 India
| | - S. KR. Tiwari
- Program Manager IUCN SSC Asian Elephant Specialist Group; Wildlife Trust of India Noida Uttar Pradesh 201301 India
| |
Collapse
|
17
|
Hartley M, Wood A, Yon L. Facilitating the social behaviour of bull elephants in zoos. ACTA ACUST UNITED AC 2019. [DOI: 10.1111/izy.12245] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- M. Hartley
- Department for Biological Science University of Chester Parkgate Road Chester CH1 4BJ United Kingdom
- Zoo and Wildlife Solutions Ltd Church View, Gresford Road, Hope, Flintshire Wrexham LL12 9PW United Kingdom
| | - A. Wood
- Department for Biological Science University of Chester Parkgate Road Chester CH1 4BJ United Kingdom
| | - L. Yon
- School of Veterinary Medicine & Science University of Nottingham Sutton Bonington Campus Leicestershire LE12 5RDUnited Kingdom
| |
Collapse
|
18
|
Schmidt H, Kappelhof J. Review of the management of the Asian elephantElephas maximusEEP: current challenges and future solutions. ACTA ACUST UNITED AC 2019. [DOI: 10.1111/izy.12233] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- H. Schmidt
- Studbook keeper Asian Elephant EEP Royal Rotterdam Zoological & Botanical Gardens Postbus 532 3000 AM Rotterdam The Netherlands
| | - J. Kappelhof
- Wageningen University & Research Droevendaalsesteeg 4 6708 PB Wageningen The Netherlands
- Royal Rotterdam Zoological & Botanical Gardens Postbus 532 3000 AM Rotterdam The Netherlands
| |
Collapse
|
19
|
Pardo MA, Poole JH, Stoeger AS, Wrege PH, O’Connell-Rodwell CE, Padmalal UK, de Silva S. Differences in combinatorial calls among the 3 elephant species cannot be explained by phylogeny. Behav Ecol 2019. [DOI: 10.1093/beheco/arz018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Michael A Pardo
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY, USA
| | | | - Angela S Stoeger
- Mammal Communication Lab, Department of Cognitive Biology, University of Vienna, Vienna, Austria
| | - Peter H Wrege
- Elephant Listening Project, Cornell Lab of Ornithology, Ithaca, NY, USA
| | - Caitlin E O’Connell-Rodwell
- Department of Otolargyngology, Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Shermin de Silva
- Division of Biological Sciences, UC San Diego, Ecology Behavior and Evolution Section, CA, USA
| |
Collapse
|
20
|
First country-wide survey of the Endangered Asian elephant: towards better conservation and management in Sri Lanka. ORYX 2019. [DOI: 10.1017/s0030605318001254] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
AbstractThe Endangered Asian elephant Elephas maximus comes into widespread conflict with agrarian communities, necessitating active management. The species’ distribution is of primary importance for management planning. However, data-based countrywide distribution maps have not been available for any of the 13 Asian elephant range states. We conducted a 5 × 5 km grid-based questionnaire survey in Sri Lanka to produce an island-wide elephant distribution map. Elephants occur over 59.9% of Sri Lanka and people are resident in 69.4% of elephant range, indicating the challenge of separating people and elephants at a landscape scale. Elephants in Sri Lanka have lost 16.1% of their range since 1960 but their current distribution remains largely contiguous. We found the range of adult males was 15.1% greater, and less seasonal, than that of herds, possibly because males have a higher tolerance for conflict with people. The distribution of conflict coincided with the co-occurrence of humans and elephants. We conclude that a human–elephant coexistence model is the only viable option for effectively mitigating human–elephant conflict and conserving elephants in Sri Lanka. The findings are currently being used to effect a paradigm change in elephant conservation and management in the country.
Collapse
|
21
|
Shaffer LJ, Khadka KK, Van Den Hoek J, Naithani KJ. Human-Elephant Conflict: A Review of Current Management Strategies and Future Directions. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2018.00235 10.3389/fevo.2018.00235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
22
|
Shaffer LJ, Khadka KK, Van Den Hoek J, Naithani KJ. Human-Elephant Conflict: A Review of Current Management Strategies and Future Directions. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2018.00235] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
|
23
|
Pokharel SS, Seshagiri PB, Sukumar R. Influence of the number of calves and lactating adult females in a herd on the adrenocortical activity of free-ranging Asian elephants. WILDLIFE RESEARCH 2019. [DOI: 10.1071/wr18163] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Abstract
ContextPhysiological stress has the potential to influence animal population persistence. The endangered Asian elephant (Elephas maximus) is involved in intense conflict with humans in many parts of its range, which likely leads to stress for individuals and groups, with consequences for population survival. Thus, it is important to understand how the elephants’ stress levels are influenced by socio-ecological factors when not directly exposed to human-induced threats, and to use this understanding to improve conservation and management strategies.
AimsThe present study was designed to provide baseline information on the link between socio-ecological factors and stress levels of undisturbed populations of elephants. The main aim was to determine the influence of a number of factors – herd size, season, number of calves and adult females present in a herd and their lactational status and body condition – on the adrenocortical activity of free-ranging adult female Asian elephants living in protected forests (without any direct exposure to human-induced threats), by measuring their faecal glucocorticoid metabolite (fGCM) levels.
MethodsA total of 145 fresh faecal samples were collected from 123 identified adult female elephants inhabiting Bandipur and Nagarahole National Parks of southern India, between the years 2013 and 2015. fGCM levels were measured by employing a group-specific standardised 11-oxoetiocholanolone enzyme immunoassay (EIA). A generalised linear mixed-effects model (GLMM) was used to assess the influence of socio-ecological factors on fGCM levels of adult female elephants.
Key resultsWhen fGCM levels were analysed with a GLMM, the following patterns were observed: fGCM levels were negatively correlated with the number of adult females (herd size) and positively correlated with the number of calves in a herd and active lactational status of an adult female. fGCM levels of adult female elephants were higher during the dry season (February to May) than wet season (August to December) and negatively correlated with body condition scores.
ConclusionsAdrenocortical activity of female elephants is significantly influenced by the number of calves and adult females present in the herd, seasonality and lactational status.
ImplicationsIt is important to consider the influence of multiple ecological and social correlates when assessing and interpreting the adrenocortical activity of Asian elephants. Our findings highlight the importance of maintaining the social structure of elephants in the wild to avoid detrimental effects on their physiological health. Insights from such assessments could be used to evaluate the stress in elephants that are involved in direct conflicts with humans to take appropriate management decisions for mitigating conflicts.
Collapse
|
24
|
Social Interactions in Two Groups of Zoo-Housed Adult Female Asian Elephants ( Elephas maximus) that Differ in Relatedness. Animals (Basel) 2018; 8:ani8080132. [PMID: 30071624 PMCID: PMC6115912 DOI: 10.3390/ani8080132] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 07/26/2018] [Accepted: 07/30/2018] [Indexed: 11/17/2022] Open
Abstract
Opportunities for positive social interaction are important in captive animals, and social interactions can be used as a welfare indicator. Wild elephants live in related multigenerational herds; however, in captivity they are often managed in less related groups, which could impact the quality of their social interactions, and thus their welfare. Here, we used a limited social network analysis to investigate the social interactions in two groups of four female captive Asian elephants, one of which contained individuals that were all related to one another, whilst the other was a mix of related and unrelated individuals. Data on pairwise social interactions was collected from eight days of video footage using an all-occurrence sampling technique. More affiliative, and fewer agonistic interactions were observed in the related elephant group. Additionally, non-contact displacement was observed at a higher frequency in the related elephant group, which we theorise represents an established functioning hierarchy, avoiding the need for overt aggression over resources. Although kinship is not likely to be the only factor affecting captive elephant social behaviour, these findings support the recommendation that for optimal welfare, elephants should be managed in multigenerational family herds. Evaluations of social interactions such as those conducted here would have wider applicability for aiding the management of any captive social species to identify when groups might be incompatible.
Collapse
|
25
|
Matsudaira K, Ishida T, Malaivijitnond S, Reichard UH. Short dispersal distance of males in a wild white-handed gibbon (Hylobates lar
) population. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 167:61-71. [DOI: 10.1002/ajpa.23603] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Revised: 04/14/2018] [Accepted: 04/16/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Kazunari Matsudaira
- Unit of Human Biology and Genetics, Department of Biological Sciences, Graduate School of Science; The University of Tokyo; Tokyo Japan
- Department of Biology, Faculty of Science; Chulalongkorn University; Bangkok Thailand
| | - Takafumi Ishida
- Unit of Human Biology and Genetics, Department of Biological Sciences, Graduate School of Science; The University of Tokyo; Tokyo Japan
| | - Suchinda Malaivijitnond
- Department of Biology, Faculty of Science; Chulalongkorn University; Bangkok Thailand
- National Primate Research Center of Thailand, Chulalongkorn University; Saraburi Thailand
| | - Ulrich H. Reichard
- Department of Anthropology and Center for Ecology; Southern Illinois University Carbondale; Carbondale Illinois
| |
Collapse
|
26
|
Sharma R, Goossens B, Heller R, Rasteiro R, Othman N, Bruford MW, Chikhi L. Genetic analyses favour an ancient and natural origin of elephants on Borneo. Sci Rep 2018; 8:880. [PMID: 29343863 PMCID: PMC5772424 DOI: 10.1038/s41598-017-17042-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 11/18/2017] [Indexed: 12/02/2022] Open
Abstract
The origin of the elephant on the island of Borneo remains elusive. Research has suggested two alternative hypotheses: the Bornean elephant stems either from a recent introduction in the 17th century or from an ancient colonization several hundreds of thousands years ago. Lack of elephant fossils has been interpreted as evidence for a very recent introduction, whereas mtDNA divergence from other Asian elephants has been argued to favor an ancient colonization. We investigated the demographic history of Bornean elephants using full-likelihood and approximate Bayesian computation analyses. Our results are at odds with both the recent and ancient colonization hypotheses, and favour a third intermediate scenario. We find that genetic data favour a scenario in which Bornean elephants experienced a bottleneck during the last glacial period, possibly as a consequence of the colonization of Borneo, and from which it has slowly recovered since. Altogether the data support a natural colonization of Bornean elephants at a time when large terrestrial mammals could colonise from the Sunda shelf when sea levels were much lower. Our results are important not only in understanding the unique history of the colonization of Borneo by elephants, but also for their long-term conservation.
Collapse
Affiliation(s)
- Reeta Sharma
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, P-2780-156, Oeiras, Portugal.
| | - Benoit Goossens
- Organisms and Environment Division, School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK.
- Danau Girang Field Centre, c/o Sabah Wildlife Department, Wisma Muis, 88100, Kota Kinabalu, Sabah, Malaysia.
- Sabah Wildlife Department, Wisma Muis, 88100, Kota Kinabalu, Sabah, Malaysia.
- Sustainable Places Research Institute, Cardiff University, 33 Park Place, Cardiff, CF10 3BA, UK.
| | - Rasmus Heller
- Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100, Copenhagen Ø, Denmark
| | - Rita Rasteiro
- Department of Genetics and Genome Biology, University of Leicester, Adrian Building, University Road, Leicester, LE1 7RH, United Kingdom
- School of Biological Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Nurzhafarina Othman
- Organisms and Environment Division, School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK
- Danau Girang Field Centre, c/o Sabah Wildlife Department, Wisma Muis, 88100, Kota Kinabalu, Sabah, Malaysia
| | - Michael W Bruford
- Organisms and Environment Division, School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK
- Sustainable Places Research Institute, Cardiff University, 33 Park Place, Cardiff, CF10 3BA, UK
| | - Lounès Chikhi
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, P-2780-156, Oeiras, Portugal
- CNRS, Université Paul Sabatier, ENFA, UMR 5174 EDB (Laboratoire Evolution & Diversité Biologique), 118 route de Narbonne, F-31062, Toulouse, France
- Université Paul Sabatier, UMR 5174 EDB, F-31062, Toulouse, France
| |
Collapse
|
27
|
Ranjeewa AD, Pastorini J, Isler K, Weerakoon DK, Kottage HD, Fernando P. Decreasing reservoir water levels improve habitat quality for Asian elephants. Mamm Biol 2018. [DOI: 10.1016/j.mambio.2017.10.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
28
|
Nandini S, Keerthipriya P, Vidya TNC. Group size differences may mask underlying similarities in social structure: a comparison of female elephant societies. Behav Ecol 2017. [DOI: 10.1093/beheco/arx135] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
|
29
|
Seasonal variation in female Asian elephant social structure in Nagarahole-Bandipur, southern India. Anim Behav 2017. [DOI: 10.1016/j.anbehav.2017.10.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
30
|
Krzyszczyk E, Patterson EM, Stanton MA, Mann J. The transition to independence: sex differences in social and behavioural development of wild bottlenose dolphins. Anim Behav 2017. [DOI: 10.1016/j.anbehav.2017.04.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
31
|
Fritz H. Long-term field studies of elephants: understanding the ecology and conservation of a long-lived ecosystem engineer. J Mammal 2017. [DOI: 10.1093/jmammal/gyx023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
32
|
Gupta M, Joshi A, Vidya TNC. Effects of social organization, trap arrangement and density, sampling scale, and population density on bias in population size estimation using some common mark-recapture estimators. PLoS One 2017; 12:e0173609. [PMID: 28306735 PMCID: PMC5357017 DOI: 10.1371/journal.pone.0173609] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 02/22/2017] [Indexed: 11/18/2022] Open
Abstract
Mark-recapture estimators are commonly used for population size estimation, and typically yield unbiased estimates for most solitary species with low to moderate home range sizes. However, these methods assume independence of captures among individuals, an assumption that is clearly violated in social species that show fission-fusion dynamics, such as the Asian elephant. In the specific case of Asian elephants, doubts have been raised about the accuracy of population size estimates. More importantly, the potential problem for the use of mark-recapture methods posed by social organization in general has not been systematically addressed. We developed an individual-based simulation framework to systematically examine the potential effects of type of social organization, as well as other factors such as trap density and arrangement, spatial scale of sampling, and population density, on bias in population sizes estimated by POPAN, Robust Design, and Robust Design with detection heterogeneity. In the present study, we ran simulations with biological, demographic and ecological parameters relevant to Asian elephant populations, but the simulation framework is easily extended to address questions relevant to other social species. We collected capture history data from the simulations, and used those data to test for bias in population size estimation. Social organization significantly affected bias in most analyses, but the effect sizes were variable, depending on other factors. Social organization tended to introduce large bias when trap arrangement was uniform and sampling effort was low. POPAN clearly outperformed the two Robust Design models we tested, yielding close to zero bias if traps were arranged at random in the study area, and when population density and trap density were not too low. Social organization did not have a major effect on bias for these parameter combinations at which POPAN gave more or less unbiased population size estimates. Therefore, the effect of social organization on bias in population estimation could be removed by using POPAN with specific parameter combinations, to obtain population size estimates in a social species.
Collapse
Affiliation(s)
- Manan Gupta
- Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru, India
| | - Amitabh Joshi
- Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru, India
| | - T. N. C. Vidya
- Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru, India
| |
Collapse
|
33
|
de Silva S, Schmid V, Wittemyer G. Fission–fusion processes weaken dominance networks of female Asian elephants in a productive habitat. Behav Ecol 2016. [DOI: 10.1093/beheco/arw153] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
34
|
Meehan CL, Hogan JN, Bonaparte-Saller MK, Mench JA. Housing and Social Environments of African (Loxodonta africana) and Asian (Elephas maximus) Elephants in North American Zoos. PLoS One 2016; 11:e0146703. [PMID: 27414034 PMCID: PMC4944928 DOI: 10.1371/journal.pone.0146703] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 12/13/2015] [Indexed: 11/25/2022] Open
Abstract
We evaluated 255 African (Loxodonta africana) and Asian (Elephas maximus) elephants living in 68 North American zoos over one year to quantify housing and social variables. All parameters were quantified for the both the day and the night and comparisons were made across these time periods as well as by species and sex. To assess housing, we evaluated not only total exhibit size, but also individual animals’ experiences based on the time they spent in the unique environments into which the exhibits were subdivided. Variables developed to assess housing included measurements of area as a function of time (Total Space Experience), environment type (Indoor, Outdoor, In/Out Choice) and time spent on hard and soft flooring. Over the year, Total Space Experience values ranged from 1,273 square feet to 169,692 square feet, with Day values significantly greater than Night values (p<0.001). Elephants spent an average of 55.1% of their time outdoors, 28.9% indoors, and 16% in areas with a choice between being in or out. Time spent on hard flooring substrate ranged from 0% to 66.7%, with Night values significantly greater than Day (p<0.001). Social factors included number of animals functionally housed together (Social Experience) and social group characteristics such as time spent with juveniles and in mixed-sex groups. Overall Social Experience scores ranged from 1 to 11.2 and were significantly greater during the Day than at Night (p<0.001). There were few significant social or housing differences between African (N = 138) and Asian (N = 117) species or between males (N = 54) and females (N = 201). The most notable exception was Total Space Experience, with African and male elephants having larger Total Space Experience than Asian and female elephants, respectively (P-value<0.05). The housing and social variables evaluated herein have been used in a series of subsequent epidemiological analyses relating to various elephant welfare outcomes.
Collapse
Affiliation(s)
- Cheryl L. Meehan
- AWARE Institute, Portland, Oregon, United States of America
- * E-mail:
| | | | - Mary K. Bonaparte-Saller
- Department of Animal Science and Center for Animal Welfare, University of California Davis, Davis, California, United States of America
| | - Joy A. Mench
- Department of Animal Science and Center for Animal Welfare, University of California Davis, Davis, California, United States of America
| |
Collapse
|
35
|
Prado-Oviedo NA, Bonaparte-Saller MK, Malloy EJ, Meehan CL, Mench JA, Carlstead K, Brown JL. Evaluation of Demographics and Social Life Events of Asian (Elephas maximus) and African Elephants (Loxodonta africana) in North American Zoos. PLoS One 2016; 11:e0154750. [PMID: 27415437 PMCID: PMC4945030 DOI: 10.1371/journal.pone.0154750] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 04/16/2016] [Indexed: 11/19/2022] Open
Abstract
This study quantified social life events hypothesized to affect the welfare of zoo African and Asian elephants, focusing on animals that were part of a large multi-disciplinary, multi-institutional elephant welfare study in North America. Age was calculated based on recorded birth dates and an age-based account of life event data for each elephant was compiled. These event histories included facility transfers, births and deaths of offspring, and births and deaths of non-offspring herd mates. Each event was evaluated as a total number of events per elephant, lifetime rate of event exposure, and age at first event exposure. These were then compared across three categories: species (African vs. Asian); sex (male vs. female); and origin (imported vs. captive-born). Mean age distributions differed (p<0.05) between the categories: African elephants were 6 years younger than Asian elephants, males were 12 years younger than females, and captive-born elephants were 20 years younger than imported elephants. Overall, the number of transfers ranged from 0 to 10, with a 33% higher age-adjusted transfer rate for imported African than imported Asian elephants, and 37% lower rate for imported females than males (p<0.05). Other differences (p<0.05) included a 96% higher rate of offspring births for captive-born females than those imported from range countries, a 159% higher rate of birthing event exposures for captive-born males than for their imported counterparts, and Asian elephant females being 4 years younger than African females when they produced their first calf. In summarizing demographic and social life events of elephants in North American zoos, we found both qualitative and quantitative differences in the early lives of imported versus captive-born elephants that could have long-term welfare implications.
Collapse
Affiliation(s)
- Natalia A. Prado-Oviedo
- Center for Species Survival, Smithsonian Conservation Biology Institute, Smithsonian National Zoological Park, Front Royal, Virginia, United States of America
- Department of Environmental Science and Policy, George Mason University, Fairfax, Virginia, United States of America
| | - Mary K. Bonaparte-Saller
- Department of Animal Science and Center for Animal Welfare, University of California Davis, Davis, California, United States of America
| | - Elizabeth J. Malloy
- Department of Mathematics and Statistics, American University, 4400 Massachusetts Ave. NW, Washington, District of Columbia, United States of America
| | | | - Joy A. Mench
- Department of Animal Science and Center for Animal Welfare, University of California Davis, Davis, California, United States of America
| | - Kathy Carlstead
- Independent Researcher, Portland, Oregon, United States of America
| | - Janine L. Brown
- Center for Species Survival, Smithsonian Conservation Biology Institute, Smithsonian National Zoological Park, Front Royal, Virginia, United States of America
| |
Collapse
|
36
|
Goffe AS, Zinner D, Fischer J. Sex and friendship in a multilevel society: behavioural patterns and associations between female and male Guinea baboons. Behav Ecol Sociobiol 2016; 70:323-336. [PMID: 26900211 PMCID: PMC4748025 DOI: 10.1007/s00265-015-2050-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 12/02/2015] [Accepted: 12/07/2015] [Indexed: 11/30/2022]
Abstract
One key question in social evolution is the identification of factors that promote the formation and maintenance of stable bonds between females and males beyond the mating context. Baboons lend themselves to examine this question, as they vary in social organisation and male-female association patterns. We report the results from the first systematic observations of individually identified wild female Guinea baboons. Guinea baboons live in a multilevel society with female-biased dispersal. Although several males could be found within 5 m of females, each female chiefly associated with one "primary" male at the 2 m distance. Social interactions occurred predominantly with the primary male, and female reproductive state had little influence on interaction patterns. The number of females per primary male varied from 1 to 4. During the 17-month study period, half of the females transferred between different males one or multiple times. A subset of females maintained weaker affiliative nonsexual relationships with other "secondary" males. Units composed of primary males with females, and occasional secondary males, apparently form the core of the Guinea baboon society. The social organisation and mating patterns of Guinea and hamadryas baboons may have a common evolutionary origin, despite notable differences in relationship quality. Specifically, Guinea baboon females appear to have greater leverage in their association patterns than hamadryas baboon females. Although we cannot yet explain the lack of overt male control over females, results generally support the notion that phylogenetic descent may play an important role in shaping social systems.
Collapse
Affiliation(s)
- Adeelia S. Goffe
- Cognitive Ethology Laboratory, German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany
| | - Dietmar Zinner
- Cognitive Ethology Laboratory, German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany
| | - Julia Fischer
- Cognitive Ethology Laboratory, German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany
| |
Collapse
|
37
|
Thitaram C, Dejchaisri S, Somgird C, Angkawanish T, Brown J, Phumphuay R, Chomdech S, Kangwanpong D. Social group formation and genetic relatedness in reintroduced Asian elephants (Elephas maximus) in Thailand. Appl Anim Behav Sci 2015. [DOI: 10.1016/j.applanim.2015.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
38
|
Chakraborty S, Boominathan D, Desai AA, Vidya TNC. Using genetic analysis to estimate population size, sex ratio, and social organization in an Asian elephant population in conflict with humans in Alur, southern India. CONSERV GENET 2014. [DOI: 10.1007/s10592-014-0587-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
39
|
Ahlering MA, Eggert LS, Western D, Estes A, Munishi L, Fleischer R, Roberts M, Maldonado JE. Identifying source populations and genetic structure for savannah elephants in human-dominated landscapes and protected areas in the Kenya-Tanzania borderlands. PLoS One 2012; 7:e52288. [PMID: 23300634 PMCID: PMC3530563 DOI: 10.1371/journal.pone.0052288] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Accepted: 11/13/2012] [Indexed: 11/19/2022] Open
Abstract
We investigated the genetic metapopulation structure of elephants across the trans Rift Valley region of Kenya and Tanzania, one of the remaining strongholds for savannah elephants (Loxodonata africana) in East Africa, using microsatellite and mitochondrial DNA (mtDNA) markers. We then examined this population structure to determine the source population for a recent colonization event of savannah elephants on community-owned land within the trans rift valley region. Four of the five sampled populations showed significant genetic differentiation (p<0.05) as measured with both mtDNA haplotypes and microsatellites. Only the samples from the adjacent Maasai Mara and Serengeti ecosystems showed no significant differentiation. A phylogenetic neighbour-joining tree constructed from mtDNA haplotypes detected four clades. Clade four corresponds to the F clade of previous mtDNA studies that reported to have originated in forest elephants (Loxodonta cyclotis) but to also be present in some savannah elephant populations. The split between clade four and the other three clades corresponded strongly to the geographic distribution of mtDNA haplotypes across the rift valley in the study area. Clade four was the dominant clade detected on the west side of the rift valley with rare occurrences on the east side. Finally, the strong patterns of population differentiation clearly indicated that the recent colonists to the community-owned land in Kenya came from the west side of the rift valley. Our results indicate strong female philopatry within the isolated populations of the trans rift valley region, with gene flow primarily mediated via male movements. The recent colonization event from Maasai Mara or Serengeti suggests there is hope for maintaining connectivity and population viability outside formal protected areas in the region.
Collapse
Affiliation(s)
- Marissa A Ahlering
- Division of Biological Sciences, University of Missouri, Columbia, Missouri, United States of America.
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Problem-elephant translocation: translocating the problem and the elephant? PLoS One 2012; 7:e50917. [PMID: 23236404 PMCID: PMC3517608 DOI: 10.1371/journal.pone.0050917] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 10/26/2012] [Indexed: 11/23/2022] Open
Abstract
Human-elephant conflict (HEC) threatens the survival of endangered Asian elephants (Elephas maximus). Translocating “problem-elephants” is an important HEC mitigation and elephant conservation strategy across elephant range, with hundreds translocated annually. In the first comprehensive assessment of elephant translocation, we monitored 16 translocations in Sri Lanka with GPS collars. All translocated elephants were released into national parks. Two were killed within the parks where they were released, while all the others left those parks. Translocated elephants showed variable responses: “homers” returned to the capture site, “wanderers” ranged widely, and “settlers” established home ranges in new areas soon after release. Translocation caused wider propagation and intensification of HEC, and increased elephant mortality. We conclude that translocation defeats both HEC mitigation and elephant conservation goals.
Collapse
|
41
|
Ahlering MA, Maldonado JE, Fleischer RC, Western D, Eggert LS. Fine-scale group structure and demography of African savanna elephants recolonizing lands outside protected areas. DIVERS DISTRIB 2012. [DOI: 10.1111/j.1472-4642.2012.00896.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
|
42
|
de Silva S, Wittemyer G. A Comparison of Social Organization in Asian Elephants and African Savannah Elephants. INT J PRIMATOL 2012. [DOI: 10.1007/s10764-011-9564-1] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
43
|
Herler A, Stoeger AS. Vocalizations and associated behaviour of Asian elephant (Elephas maximus) calves. BEHAVIOUR 2012. [DOI: 10.1163/156853912x648516] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
44
|
de Silva S, Ranjeewa ADG, Kryazhimskiy S. The dynamics of social networks among female Asian elephants. BMC Ecol 2011; 11:17. [PMID: 21794147 PMCID: PMC3199741 DOI: 10.1186/1472-6785-11-17] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Accepted: 07/27/2011] [Indexed: 11/28/2022] Open
Abstract
Background Patterns in the association of individuals can shed light on the underlying conditions and processes that shape societies. Here we characterize patterns of association in a population of wild Asian Elephants at Uda Walawe National Park in Sri Lanka. We observed 286 individually-identified adult female elephants over 20 months and examined their social dynamics at three levels of organization: pairs of individuals (dyads), small sets of direct companions (ego-networks), and the population level (complete networks). Results Corroborating previous studies of this and other Asian elephant populations, we find that the sizes of elephant groups observed in the field on any particular day are typically small and that rates of association are low. In contrast to earlier studies, our longitudinal observations reveal that individuals form larger social units that can be remarkably stable across years while associations among such units change across seasons. Association rates tend to peak in dry seasons as opposed to wet seasons, with some cyclicity at the level of dyads. In addition, we find that individuals vary substantially in their fidelity to companions. At the ego-network level, we find that despite these fluctuations, individuals associate with a pool of long-term companions. At the population level, social networks do not exhibit any clear seasonal structure or hierarchical stratification.
Collapse
Affiliation(s)
- Shermin de Silva
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | | | | |
Collapse
|
45
|
Genetic diversity, social structure, and conservation value of the elephants of the Nakai Plateau, Lao PDR, based on non-invasive sampling. CONSERV GENET 2010. [DOI: 10.1007/s10592-010-0148-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
46
|
Frère C, Krützen M, Mann J, Watson-Capps J, Tsai Y, Patterson E, Connor R, Bejder L, Sherwin W. Home range overlap, matrilineal and biparental kinship drive female associations in bottlenose dolphins. Anim Behav 2010. [DOI: 10.1016/j.anbehav.2010.06.007] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
47
|
Thitaram C, Somgird C, Mahasawangkul S, Angkavanich T, Roongsri R, Thongtip N, Colenbrander B, van Steenbeek FG, Lenstra JA. Genetic assessment of captive elephant (Elephas maximus) populations in Thailand. CONSERV GENET 2009. [DOI: 10.1007/s10592-009-0018-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
48
|
Parsons K, Balcomb K, Ford J, Durban J. The social dynamics of southern resident killer whales and conservation implications for this endangered population. Anim Behav 2009. [DOI: 10.1016/j.anbehav.2009.01.018] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
49
|
Intrasexual chemical communication and social responses of captive female African elephants, Loxodonta africana. Anim Behav 2008. [DOI: 10.1016/j.anbehav.2007.12.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
50
|
POTEAUX CHANTAL, BUSQUET NICOLAS, GOUAT PATRICK, KATONA KRISZTIÁN, BAUDOIN CLAUDE. Socio-genetic structure of mound-building mice, Mus spicilegus, in autumn and early spring. Biol J Linn Soc Lond 2008. [DOI: 10.1111/j.1095-8312.2007.00944.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|