Causes and correlates of calf mortality in captive Asian elephants (Elephas maximus)

Juvenile mortality is a key factor influencing population growth rate in density-independent, predation-free, well-managed captive populations. Currently at least a quarter of all Asian elephants live in captivity, but both the wild and captive populations are unsustainable with the present fertility and calf mortality rates. Despite the need for detailed data on calf mortality to manage effectively populations and to minimize the need for capture from the wild, very little is known of the causes and correlates of calf mortality in Asian elephants. Here we use the world''s largest multigenerational demographic dataset on a semi-captive population of Asian elephants compiled from timber camps in Myanmar to investigate the survival of calves (n = 1020) to age five born to captive-born mothers (n = 391) between 1960 and 1999. Mortality risk varied significantly across different ages and was higher for males at any age. Maternal reproductive history was associated with large differences in both stillbirth and liveborn mortality risk: first-time mothers had a higher risk of calf loss as did mothers producing another calf soon (<3.7 years) after a previous birth, and when giving birth at older age. Stillbirth (4%) and pre-weaning mortality (25.6%) were considerably lower than those reported for zoo elephants and used in published population viability analyses. A large proportion of deaths were caused by accidents and lack of maternal milk/calf weakness which both might be partly preventable by supplementary feeding of mothers and calves and work reduction of high-risk mothers. Our results on Myanmar timber elephants with an extensive keeping system provide an important comparison to compromised survivorship reported in zoo elephants. They have implications for improving captive working elephant management systems in range countries and for refining population viability analyses with realistic parameter values in order to predict future population size of the Asian elephant.     

Why inter‐country loans will not help sumatra's elephants

Asian elephants (Elephas maximus) in western zoos are likely to become extinct unless elephants are regrouped into breeding units or additional elephants are imported from range States. There have been proposals for the export of elephants from elephant camps in Sumatra, Indonesia. In exchange, zoos would be expected to provide funds or support ‘in kind’ for the camps or for the conservation of wild elephants. Most of the elephants in the Sumatran camps were captured because of crop‐raiding problems around protected areas or because elephant habitat has been and continues to be lost to development schemes and illegal conversion of protected areas to agriculture. Capture‐related mortality rates are high and conditions in the camps are poor, with low standards of veterinary care and husbandry. This is partly due to over‐crowding and inadequate budgets. It might seem, therefore, that the loan of elephants to western zoos would improve the lot of these elephants and reduce the pressures on the camps. However, we show that both total and annual demand for Asian elephants, and particularly Sumatran elephants (E. m. sumatranus), by western zoos are low, and consequently the resources generated by any loan scheme would be limited. Elephant loan schemes are unlikely to have significant beneficial impact on either the conservation or welfare of elephants in Sumatra. More importantly, a credible loan scheme would require a permanent moratorium on the capture of wild elephants in Sumatra. Such a moratorium is needed to prevent illicit captures for sale or loan. At present, wild elephants are caught to replace those that die at the camps or are moved to other facilities. Without a moratorium, the loan of elephants to overseas zoos would contribute directly to reductions in wild elephant populations in Sumatra. However, a moratorium is likely to prove impossible to enforce, and this alone should call into question the desirability of any loan scheme. Zoo Biol 25:235–246, 2006. © 2006 Wiley‐Liss, Inc.     

A test of the counting of elephants from the air

Aerial counts of elephants made three times a day over the same region tended to be consistent if due allowance is made for observed movements to and from the area. There was little difference between observers when two were present. Ground counts made on the same day as the aerial counts tended to return lower totals, due probably to elephants in dense vegetation being hidden from the ground observer but visible from the air. It is concluded that aerial survey is the most efficient way of counting elephants, at least in the Queen Elizabeth National Park.     

Seasonality of reproduction in Asian elephants Elephas maximus and African elephants Loxodonta africana: underlying photoperiodic cueing?

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犬、猫肾功能衰竭的中西医结合疗法

本文介绍了中医的肾脏生理功能理论、阐述了目前西兽医及中兽医对犬猫急性肾功能衰竭、慢性肾功能衰竭发病原因的认识,分析了肾功能衰竭的中医辨证分型和急性肾功能衰竭、慢性肾功能衰竭的治疗原则。     

Ultrasonography: an important tool in captive breeding management in elephants and rhinoceroses

Nearly two decades ago, modern wildlife medicine started to gradually use the advantages of the non-invasive ultrasonography, which was already well established in human and classical veterinary medicine. For more than one decade now, the application of imaging ultrasound for reproductive assessments and as a supportive tool during assisted reproduction procedures such as artificial insemination (AI) in elephants and rhinoceroses has dramatically improved the breeding success in captive breeding programmes. The opportunity for identifying potential breeding candidates on the basis of their reproductive health status is widely used for natural mating or for AI, today. The longitudinal sonographic monitoring of pathological processes on the internal female genital tract allowed the identification of pathogenetic causes for the rapid infertility development in older nulliparous females. The factors causing temporary infertility in captive male elephants and rhinoceroses were also identified by the use of ultrasound. Today, ultrasonography is the golden standard for reproductive assessments in megavertebrates such as elephants and rhinoceroses in captive management settings and also in the wild.     

Positive Reinforcement Training for a Trunk Wash in Nepal's Working Elephants: Demonstrating Alternatives to Traditional Elephant Training Techniques

Many trainers of animals in the zoo now rely on positive reinforcement training to teach animals to voluntarily participate in husbandry and veterinary procedures in an effort to improve behavioral reliability, captive management, and welfare. However, captive elephant handlers in Nepal still rely heavily on punishment- and aversion-based methods. The aim of this project was to determine the effectiveness of secondary positive reinforcement (SPR) in training free-contact elephants in Nepal to voluntarily participate in a trunk wash for the purpose of tuberculosis testing. Five female elephants, 4 juveniles and 1 adult, were enrolled in the project. Data were collected in the form of minutes of training, number of offers made for each training task, and success rate for each task in performance tests. Four out of 5 elephants, all juveniles, successfully learned the trunk wash in 35 sessions or fewer, with each session lasting a mean duration of 12 min. The elephants' performance improved from a mean success rate of 39.0% to 89.3% during the course of the training. This study proves that it is feasible to efficiently train juvenile, free-contact, traditionally trained elephants in Nepal to voluntarily and reliably participate in a trunk wash using only SPR techniques.     

Elephants of south‐east Angola in war and peace: their decline,re‐colonization and recent status

Angola’s intermittent 27‐year civil war displaced over four million people and decimated wildlife populations. During the 1980s, African elephants (Loxodonta africana Blumenbach) in Angola drew international alarm with reports of 100,000 elephants killed. Luiana Partial Reserve (PR), a conservation area in south‐east Angola, was the military operations centre for UNITA (National Union for the Total Independence of Angola), which used elephant ivory to pay for arms and meat. However, the full impact of the civil war on elephants is uncertain because there are no reliable estimates of Angolan elephant populations. Following the end of the civil war in 2002, our three aerial surveys of Luiana PR indicated that elephant numbers are increasing rapidly, from 366 in January 2004 to 1827 in November 2005, and expanding their range in the Reserve. Concurrently, elephants tagged with satellite collars in northern Botswana and the Caprivi Strip, Namibia, moved into Luiana PR. To facilitate re‐colonization and conservation of elephants and other wildlife in Luiana PR, we recommend: (i) realignment of the veterinary fence on the Botswana–Namibia border; (ii) development of effective land use management and anti‐poaching programmes; (iii) clearing of landmines; (iv) designation of the Reserve a national park; and (v) development of ecotourism and community conservation programmes.     

Activity budgets and the relationship between feeding and stereotypic behaviors in Asian elephants (Elephas maximus) in a Zoo

Activity budgets were studied in eight Asian elephants (Elephas maximus) at Chester Zoo (UK) for 35 days, between January and November 1999. Recordings were made between 10:00 and 16:00 hr (with most behavior frequencies calculated between 10:00 and 14:00 hr). The elephants exhibited variation in activity depending on their age, sex, the time of day and the time of year. Only the five adult cows exhibited stereotypic behavior, with frequencies ranging from 3.9 to 29.4% of all observations. These elephants exhibited individual, diurnal and seasonal variation in stereotypic behavior. This has implications for studies that use short sampling periods and may make comparisons of data collected at different times of the day or year invalid. The six adult elephants spent 27.4–41.4% of the time feeding (between 10:00 and 14:00 hr), 22.9–42.0% standing still, 6.1–19.2% walking and 3.9–9.6% dusting. The hypothesis that the frequency of stereotypic behavior in adult cow elephants was negatively correlated with the frequency of feeding behavior was tested and was found to be true. Stereotypic behavior increased in frequency toward the end of the day—while waiting to return to the elephant house for food—and elephants spent more time stereotyping during the winter months than during the summer months. Elephants were inactive (i.e. exhibited behaviors other than locomotion) for between 70.1 and 93.9% of the time. Creating more opportunities for elephants to exhibit foraging behavior and the introduction of greater unpredictability into management regimes, especially feeding times, may reduce the frequency of stereotypic behavior and increase general activity levels. Zoo Biol 28:79–97, 2009. © 2008 Wiley-Liss, Inc.     

Elephants and human color-blind deuteranopes have identical sets of visual pigments

Being the largest land mammals, elephants have very few natural enemies and are active during both day and night. Compared with those of diurnal and nocturnal animals, the eyes of elephants and other arrhythmic species, such as many ungulates and large carnivores, must function in both the bright light of day and dim light of night. Despite their fundamental importance, the roles of photosensitive molecules, visual pigments, in arrhythmic vision are not well understood. Here we report that elephants (Loxodonta africana and Elephas maximus) use RH1, SWS1, and LWS pigments, which are maximally sensitive to 496, 419, and 552 nm, respectively. These light sensitivities are virtually identical to those of certain "color-blind" people who lack MWS pigments, which are maximally sensitive to 530 nm. During the day, therefore, elephants seem to have the dichromatic color vision of deuteranopes. During the night, however, they are likely to use RH1 and SWS1 pigments and detect light at 420-490 nm.     

Elephants caught in the middle: impacts of war, fences and people on elephant distribution and abundance in the Caprivi Strip, Namibia

We conducted wet [26 March–4 April 2003 (Apr03)] and dry [1–8 November 2005 (Nov05)] season aerial surveys of African elephants ( Loxodonta africana Blumenbach) in the Caprivi Strip, Namibia to provide an updated status report on elephant numbers and distribution and assist with a historical analysis of elephant distribution and abundance in the Caprivi Strip. During the wet season when water was available in seasonal pans, elephants were widely distributed throughout the survey area. In contrast, during the dry season, a majority of elephant herds occurred within 30 km of the perennial Kwando, Linyanti and Okavango rivers and few herds occurred within the West Caprivi Game Reserve where water in the seasonal pans was limited. We estimated 5318 elephants for the 7731-km² survey area (0.71 elephants km⁻²) for the Apr03 wet season survey and 6474 elephants for the 8597-km² survey area (0.75 elephants km⁻²) for the Nov05 dry season survey. Based on our aerial surveys and reports of elephant numbers and distribution from historical aerial surveys and telemetry studies, civil war, veterinary fences and human activities appear to have effected changes in African elephant abundance, distribution and movements in the Caprivi Strip, Namibia since 1988 when the first comprehensive aerial surveys were conducted.     

Demography of captive Asian elephants (Elephas maximus) in southern India

Historically, the Asian elephant has never bred well in captivity. We have carried out demographic analyses of elephants captured in the wild or born in captivity and kept in forest timber camps in southern India during the past century. The average fecundity during this period was 0.095/adult female/year. During 1969–89, however, the fecundity was higher at 0.155/adult female/year, which compares favorably with wild populations. There was seasonality in births with a peak in January. The sex ratio of 129 male to 109 female calves at birth is not significantly different from equality, although the excess of male calves born mainly to mothers 20–40 years old may have biological significance. Mortality rates were higher in females than in males up to age 10, but much lower in females than in males above age 10 years. The population growth rate, based on the lower secundity over the century, was 0.5% per year, and based on the higher secundity during 1969–89, was 1.8% per year. The analyses thus showed that timber camp elephants in southern India could potentially maintain a stationary or increasing population without resorting to captures from the wild. Breeding efforts for elephants in zoos can thus profitably learn from the experience of traditional management systems in part of Asia. Zoo Biol 16:263–272, 1997. © 1997 Wiley-Liss, Inc.     

The sexually active states of free-ranging male African elephants (Loxodonta africana): defining musth and non-musth using endocrinology, physical signals, and behavior

Musth in male African elephants, Loxodonta africana, is associated with increased aggressive behavior, continuous discharge of urine, copious secretions from the swollen temporal glands, and elevated androgen levels. During musth, bulls actively seek out and are preferred by estrous females although sexual activity is not restricted to the musth condition. The present study combines recently established methods of fecal hormone analysis with long-term observations on male-female associations as well as the presence and intensity of physical signals to provide a more detailed picture about the physical, physiological, and behavioral characteristics of different states of sexual activity in free-ranging African elephants. Based on quantitative shifts in individual bull association patterns, the presence of different physical signals, and significant differences in androgen levels, a total of three potential sub-categories for sexually active bulls could be established. The results demonstrate that elevations in androgen levels are only observed in sexually active animals showing temporal gland secretion and/or urine dribbling, but are not related to the age of the individual. Further, none of the sexually active states showed elevated glucocorticoid output indicating that musth does not represent an HPA-mediated stress condition. On the basis of these results, we suggest that the term "musth" should be exclusively used for the competitive state in sexually active male elephants and that the presence of urine dribbling should be the physical signal used for defining this state.     

The movement of African elephants in a human-dominated land-use mosaic

Land outside of gazetted protected areas is increasingly seen as important to the future of elephant persistence in Africa. However, other than inferential studies on crop raiding, very little is understood about how elephants Loxodonta africana use and are affected by human-occupied landscapes. This is largely a result of restrictions in technology, which made detailed assessments of elephant movement outside of protected areas challenging. Recent advances in radio telemetry have changed this, enabling researchers to establish over a 24-h period where tagged animals spend their time. We assessed the movement of 13 elephants outside of gazetted protected areas across a range of land-use types on the Laikipia plateau in north-central Kenya. The elephants monitored spent more time at night than during the day in areas under land use that presented a risk of mortality associated with human occupants. The opposite pattern was found on large-scale ranches where elephants were tolerated. Furthermore, speed of movement was found to be higher where elephants were at risk. These results demonstrate that elephants facultatively alter their behaviour to avoid risk in human-dominated landscapes. This helps them to maintain connectivity between habitat refugia in fragmented land-use mosaics, possibly alleviating some of the potential negative impacts of fragmentation. At the same time, however, it allows elephants to penetrate smallholder farmland to raid crops. The greater the amount of smallholder land within an elephant's range, the more it was utilized, with consequent implications for conflict. These findings underscore the importance of (1) land-use planning to maintain refugia; (2) incentives to prevent further habitat fragmentation; (3) the testing and application of conflict mitigation measures where fragmentation has already taken place.     

An elephantine challenge: human–elephant conflict distribution in the largest Asian elephant population,southern India

Wildlife conservation is a complex issue especially when it involves large carnivores or mega-herbivores that are conflict-prone. Karnataka state in southern India is known to harbor high density of wild elephants. This conservation success story also has opportunity costs for communities living in close proximity to elephants. Despite the fact that human–elephant conflict is a serious conservation and social issue, there is little quantitative understanding of conflict especially over large areas. Here we conduct the first analysis of human–elephant conflict distribution, severity and explanatory factors over the entire state of Karnataka. We use data from the state forest department records on villages that experience conflict, compensation payments made by the government, elephant densities, forest cover and perimeter, and presence of physical barriers to mitigate elephant conflict. In total, 60,939 incidences of crop loss were reported and US$ 2.99 m paid in compensation during April 2008–March 2011. A total of 91 people were killed by elephants and 101 elephants died in retaliatory killings during the study period. A total of 9.4 % of the state’s geographic area covering 25 of the 42 forest administrative divisions were affected. There was no significant difference in conflict incidences or compensation given between protected areas and non-protected areas. There was no correlation between conflict incidences/unit area and elephant density, forest cover, forest perimeter of protected areas and presence of physical barriers. The results depict the importance of efficient management of physical barriers, conserving key habitat linkages, and acts as baseline data for future work.     

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

With growing human and, possibly, elephant populations and a drastic increase in anthropogenic activities, human–elephant conflict in Asia has been on the rise. The Alur area in Karnataka state, southern India, is one such case in point, which has witnessed increasing levels of human–elephant conflict over the last two decades. The tiny, moderately protected habitat available for elephants in this human-dominated landscape does not appear to be able to support elephants over the long term. Options to deal with the escalating conflict include translocation of elephants, bringing elephants into captivity, and culling. We carried out a molecular genetic study of elephants in the Alur area to estimate the minimum number of elephants using the area, the sex ratio, genetic relatedness between individuals, and genetic structure with regard to the larger population in the landscape, so that informed management decisions could be made. Fresh dung samples were collected from the field and genotyped using 12 microsatellite loci. We found 29 unique individuals in the population, comprising 17 females and 12 males of different age classes. Relatedness between females suggested independent colonisations by discrete, small groups rather than by one cohesive clan of related females. This obviates the need for a single solution for dealing with all the females in the area in order to maintain social integrity, and has implications in terms how these elephants can be dealt with. We demonstrate how social organization inferred through molecular data from non-invasive sampling can inform management decisions.     

Asian Elephant (Elephas maximus), Pig-Tailed Macaque (Macaca nemestrina) and Tiger (Panthera tigris) Populations at Tourism Venues in Thailand and Aspects of Their Welfare

This study focused on determining the size and welfare aspects of Asian elephant, pig-tailed macaque and tiger populations at facilities open to tourists in Thailand. Data were gathered from 118 venues through direct observations and interviews with staff. A score sheet-based welfare assessment was used to calculate scores between 1 and 10, indicating each venue’s welfare situation. Factors such as freedom of movement for the animals, access to veterinary care, environmental noise quality, hygiene standards and work intensity were included in the score sheet. 1688 elephants, 371 macaques and 621 tigers were found at the venues. 89 venues exclusively kept elephants, 9 designated ‘Monkey schools’ offered macaque shows, 4 venues kept primarily tigers, mostly for petting and photo opportunities, and the remaining venues kept a mix of these animals. A strong imbalance in female to male gender ratios was recorded with about 4:1 for adult elephants and 1:4 for adult macaques. Severely inadequate welfare conditions were common, with 75% of macaques and 99% of tigers being kept at venues with scores less than 5. 86% of elephants were kept in inadequate conditions at venues with scores between 3 and 5, but a significant number of venues with scores above 5 were found. 4.6% of elephants were provided commendable conditions, reaching assessment scores of 8 and above. 71% of venues did not offer any sort of education about animals to visitors. This study is the first to assess welfare aspects of captive wild animals at tourism venues across Thailand. It concludes that significant concerns exist about the welfare of wild animals in the tourism sector of Thailand. Urgent attention needs to be given to address these concerns and prevent further suffering. But also to ensure the demand for wild animals doesn’t have a negative impact on wild populations.     

Levels of aloe mortality with and without elephants in the Thicket Biome of South Africa

Studies concerning the influence of African elephants ( Loxodonta africana ) on vegetation have produced contradictory results; some show minimal or no effect while others report significant elephant-induced effects. Elephants are generalist megaherbivores but will selectively feed from preferred plant species. We investigated the mortality of aloe plants (highly preferred food items for elephants) at five sites with elephants (treatment) and five paired sites without elephants (control) in the Eastern Cape Province of South Africa. A significantly higher proportion of aloes were dead at treatment sites and significantly more aloes that had lost their crown (headless) were found at treatment sites compared with controls. We conclude that although the proportions of dead aloes at treatment sites were significantly higher, it remains unclear whether there is a need to be concerned with the potential small-scale extinction of aloes from parts of the Eastern Cape Province. The observed mortality may merely be an artefact of the loss of large herbivores through disease (e.g. rinderpest) and hunting in the past.     

Skewed birth sex ratio and premature mortality in elephants

Sex allocation theories predict equal offspring number of both sexes unless differential investment is required or some competition exists. Left undisturbed, elephants reproduce well and in approximately even numbers in the wild. We report an excess of males are born and substantial juvenile mortality occurs, perinatally, in captivity. Studbook data on captive births (CB, n = 487) and premature deaths (PD, <5 years of age; n = 164) in Asian and African elephants in Europe and North America were compared with data on Myanmar timber (Asian) elephants (CB, n = 3070; PD, n = 738). Growth in CB was found in three of the captive populations. A significant excess of male births occurred in European Asian elephants (ratio: 0.61, P = 0.044) and in births following artificial insemination (0.83, P = 0.003), and a numerical inclination in North American African elephants (0.6). While juvenile mortality in European African and Myanmar populations was 21–23%, it was almost double (40–45%) in all other captive populations. In zoo populations, 68–91% of PD were within 1 month of birth with stillbirth and infanticide being major causes. In Myanmar, 62% of juvenile deaths were at >6 months with maternal insufficient milk production, natural hazards and accidents being the main causes. European Asian and Myanmar elephants PD was biased towards males (0.71, P = 0.024 and 0.56, P < 0.001, respectively). The skewed birth sex ratio and high juvenile mortality hinder efforts to help captive populations become self-sustaining. Efforts should be invested to identify the mechanism behind these trends and seek solutions for them.     

The daily activity of the elephant in the Rwenzori National Park, Uganda

Eighteen elephants were followed individually in the Rwenzori National Park, Uganda for varying periods and their activity noted at 4-min intervals. Continuous data extending over 24 h or more were collected from seven of these elephants. About 75% of the total time was spent in feeding and about 75% of the feeding activity consisted of grazing or feeding at ground level. There were three feeding peaks, one in the morning, another in the afternoon and the third around midnight. The feeding rate tended to increase during the day. The proportion of the total feeding time spent in browsing increased in the dry season. Walking took place mainly at dusk. The principal sleeping period occurred during the small hours of the morning with a shorter rest period in the early afternoon. The elephants defaecated about eleven times in the 24 h and drank an average of 1–3 times. The rate of progress through the bush averaged 0–5 km/h. Comparisons are made with published data concerning the activity patterns of waterbuck and warthog in the Rwenzori Park and of elephants in the Tsavo National Park, Kenya.