One anti-predator adaptation of R. eldii is periodically forming large groups or herds, even though these deer are usually solitary creatures. Large groups decrease the risk of predation, both by increasing the chance that a predator will kill a neighboring animals rather than a lone individual, and by the increased vigilance for predators which can be provided by all members of the group.
The most common predators of R. eldii are tigers, leopards, and dholes. But only the latter two predators still exist in abundant numbers in the present range of this deer. Jackals and occasionally feral dogs also hunt R. eldii. Poaching by humans is a serious problem to Eld's deer populations.
Known Predators:
Adults weigh between 70 and 130 kg. Eld's deer have selenodont teeth, a large body and foregut fermentation type of digestion.
Eld's deer, like many other cervids, have a reddish brown to gray colored coat. They are similar in size to white-tailed deer, but differ somewhat in appearance. They have uniquely shaped antlers that are replaced every year. The antlers of Eld's deer are shaped in one continuous curve from the pedicle on the head to the very tip of the antler. There is a lesser branch of the antler that is positioned directly off the pedicel that grows in the direction of the front of the head.
Range mass: 70 to 130 kg.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger; ornamentation
The maximum recorded longevity of a R. e. siamensis male in captivity is 14 years and 11 months. Females can live up to 19 years and 7 months in captivity.
Range lifespan
Status: captivity: 19 (high) years.
The main habitat for Eld's deer is referred to as an indaing forest and is usually dominated by the tree Dipterocarpus tuberculatus. Indaing refers to sandy, flat terrain that floods seasonally. The range of Eld's deer also includes monsoonal forest. Rucervus eldii thamin is found in a variety of habitats, ranging from dry scrub and thorn forest to open deciduous forest. There are three main types of deciduous forests in southeastern Asia: dipterocarp (indaing), dry (thandahat), and mixed (teak). All three of these receive between 100 and 200 cm of rainfall a year.
The ability of Eld's deer to obtain adequate amounts of nutrients to sustain both the bone growth and body mass of males, and the gestation and lactation needs of females, depends heavily on the types and abundances of food sources in the habitat. Rucervus eldii exhibits seasonal movements that are slightly correlated with crop cycles. They tend to wander farther from crop land during the hot-dry season, mainly because they are moving closer to existing water holes.
Habitat Regions: temperate ; tropical ; terrestrial
Terrestrial Biomes: savanna or grassland ; chaparral ; forest ; scrub forest
Other Habitat Features: agricultural
Eld's deer are sometimes refered to as brow-antlered deer. They were previously considered a member of the genus Cervus as Cervus eldi or Cervus eldii.
Most cervids have numerous glands on their feet, legs, and faces. These scent glands are used for intraspecific communication. Males often use chemosignaling through urine and feces to inform females that they are in reproductive condition. Not only do cervids utilize chemosignaling, they also use sight and touch. This is mostly commonly displayed before breeding when their antlers are at their largest. Rucervus eldii does not use combat as its primary mode of hierarchy, but it is sometimes necessary to fend off a competing male.
Communication Channels: visual ; tactile ; chemical
Other Communication Modes: scent marks
Perception Channels: visual ; tactile ; acoustic ; chemical
All three subspecies of R. eldii have become threatened. Conservation of these deer in tropical regions is difficult because of the fragmentation of their forest home caused by farming. These deer are a targer for poaching, as they can be used for food, trophies, and "traditional" medicinal products. The increase of the human population within the range of this species puts a additional stress upon these animals. There is a lack of funding for protection.
One of the subspecies, R. e. eldii, has become so rare that survival will eventually rely on the practice of gene exchange of the wild and captive organisms by means of assisted reproduction. This type of assisted breeding is being used in Thailand and Burma/Myanmar on the other subspecies as well.
Poaching reduced the R. e. siamensis population from a reported 500 individuals in 1964, to 26 in 1976. Hainan Datian Nature Reserve was established to help R. e. siamensis recover, and the population increased to 151 individuals by 1986.
US Federal List: no special status
CITES: appendix i
IUCN Red List of Threatened Species: endangered
Rucervus eldii is known to feed heavily on the cultivated crops of the local farmers. These deer are a major destroyer of crops, and are considered by locals to be a significant agricultural problem.
Negative Impacts: crop pest
Eld's deer are hunted as game animals and are used as a food source. They are prized as a game animal because of their antlers and hides. There have been cases when these deer have been used for "traditional" medicinal products. Oftentimes, Els's deer are poached for this purpose. In addition to these destructive uses, Eld's deer have become a major zoo animal, especially since their populations are decreasing in the wild.
Positive Impacts: food ; body parts are source of valuable material; source of medicine or drug ; research and education
Rucervus eldii plays an important role in dispersing seeds due to its dependence upon fruit as a food source. This species is probably also important in structuring plant communities as a result of its browsing behavior.
Ecosystem Impact: disperses seeds
Rucervus eldii is a species known to graze and browse opportunistically on wild fruits and cultivated crops from nearby fields. A few commonly eaten crops are rice, lentils, maize, peas and rape. Rucervus eldii thamin tends to eat the fruits of various woody species such as Emblica officinalis, Terminalia chebula, and Diospyrous burmanica. They also eat forbs and grasses in these areas.
Rucervus eldii is closely associated with areas that are seasonally burned. These deer eat the new grasses as they emerge after the burn.
Feeding may vary seasonally, not just with food availability, but with reproductive considerations. During rut males, experience a decline in body weight. This is proably due to a decrease in their food intake.
All cervids are foregut fermentators. This means that they have four-chambered stomachs, and are able to extract the majority of the nutrients offered by their poor quality food source.
Plant Foods: leaves; wood, bark, or stems; seeds, grains, and nuts; fruit
Primary Diet: herbivore (Folivore )
Eld's deer (Rucervus eldii) are indigenous to Southeast Asia. They were discovered in the Manipur Valley of India in 1838 by Lieutenant Percy Eld. Three recognized subspecies of R. eldii exist today. They are Rucervus eldii eldii in Manipur, Rucervus eldii thamin, previously in Burma/Myanmar and the Malay Peninsula, and Rucervus eldii siamensis, in Thailand, Annam, and Hainan island. The subspecies Rucervus eldii thamin is now restricted to Burma/Myanmar. Rucervus eldii siamensis is found throughout Hainan island . Some individuals of R. eldii live as far north as 48°N. Eld's deer have also been documented in Cambodia, Laos, and Vietnam.
Biogeographic Regions: palearctic (Native ); oriental (Native )
Rucervus eldii exhibits polygynous mating.
Mating System: polygynous
Rucervus eldii females can begin reproducing at 2 years of age and typically continue to reproduce until they are 10 years of age. They begin estrus in the late winter or early spring. They exhibit a long period of ovarian activity of 225 to 342 days, during which the females average 10 to 17 estrous cycles. Then after they have mated, females enter anestrus. This is just the opposite of estrus, and is a period when they are not sexually receptive. This cycle occurs in the autumn months. Some studies have shown that the presence of males triggers ovarian function in females.
The proportion of males to females at birth tends to be a 1:1. The average gestation period for Eld's deer is about 34 weeks or 8 and a half months. Females of the subspecies R. eldii siamensis have been shown to give birth annually for up to 6 consecutive years. Females are fertile for a maximum of 12 to 14 years. Most births of R. e. siamensis occur between October and November (75 percent if 171 reported births). Of all births, 94 percent occurred betweem October 1 to February 28. About 92 percent of births involve single young, while the remaining 8 percent are twins. Most twins are apparently stillborn or die within a few days of birth.
The average weight of a newborn from the subspecies R. e. thamin is between 4.7 and 4.8 kg. Newborns of R. e. eldii are slightly larger, averaging between 4.7 and 6 kg. The young are weaned at about 5 months of age.
Breeding interval: Eld's deer tend to breed once per year.
Breeding season: Breeding occurs from February to May.
Range number of offspring: 1 to 2.
Average number of offspring: 1.
Average gestation period: 7.93 months.
Range weaning age: 4 to 6 months.
Average age at sexual or reproductive maturity (female): 2 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
Like most cervids, R. eldii mothers hide their young immediately after birth. Females typically give birth during the cool-dry season when the flood waters have receded and vegetation has begun to grow. This provides the young with shelter and helps to conceal them.
After 4 to 5 months, the fawns are weaned. By the end of time of weaning, the climate has changed to the hot-dry season, and the deer tend to migrate. The 4 to 5 month nursing period allows fawns to have sufficient time to increase their mobility, so they are able to travel with the herd.
Fawns are primarily raised by their mothers. Males are around, usually watching over the herd, but they do not participate in most of the parental care.
Parental Investment: no parental involvement; altricial ; pre-fertilization (Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Male, Female); pre-independence (Protecting: Male, Female)
Eld's deer (Rucervus eldii or Panolia eldii[5]), also known as the thamin or brow-antlered deer, is an endangered species of deer endemic to South Asia and Southeast Asia.[2]
The species was first described by John McClelland in 1840 based on specimens obtained in Manipur, India.[6] It was described more detailed by Percy Eld in 1841; it was suggested to call the deer Cervus Eldii.[7] McClelland coined the scientific name Cervus (Rusa) frontals in 1843.[8] In 1850, John Edward Gray proposed the name Panolia eldii for the deer.[9][10] It has recently been proposed that it should be moved back to the genus Panolia on the basis of recent genetic findings that place it closer to Pere David's deer than to other members of the genus Rucervus.[5][11]
The three subspecies of the Eld's deer are:[2]
The following measurements have been reported for the Eld's deer:[14][15][16][17]
The deer are generally of medium size and are similar to the size and shape of the related barasingha (R. duvaucelli). The species has a very regal and graceful Cervus-like physique. Its legs are thin and long and have a long body with a large head on a thin neck. The throat of a male has a thick mane of long hair. Males (stags) are taller and heavier than females (hinds or does). Their coats, rough and coarse, change colour with the season; in summer the colour is reddish-brown, while in winter, it turns dark brown, with males tending to be darker than the females. The tail is short in length and the rump has no distinct patch. Despite these features, they have actually related to the Père David's deer.[5] The antlers, bow- or lyre-shaped, do not grow upwards, but tend to grow outwards and then inwards; a smaller branch grows towards the front of the head. The brow tines are especially long and noticeable. The brow-antlered deer is so named because they have long brow tines. The antlers of Eld's deer are structurally different from those of barasingha but have similarities to those of Père David's deer, consistent with the genetic relationship.[11] They shed their antlers every year, with the largest size attained during the breeding season.[14][16][17]
The conservation status of three subspecies of Eld's deer, by country, are:
The Keibul Lamjao National Park (KLNP), covering an area of 40 km2 (15.4 sq mi) of marshland called the Phumdis within the larger Loktak Lake, was gazetted in 1977 specifically to protect the Rucervus eldii eldii, the sangai in Meitei. Over time, public awareness and local support have evolved for conserving the subspecies of the endemic endangered Elds' deer. Concerted actions have been initiated to stop the encroachment of the park and adequate security arrangements have been made to stop poaching. This fact is very somberly presented in a story form in a popular children's magazine called Chandamama, which gives a first-person symbolic narrative by the affected 'deer' itself. The final conclusion by the deer, quoted below, concisely puts the security provided in the park in a proper perspective.[18]
" 'Thanks to these youngsters who live nearby', he said. I was happy and felt indebted to the youngsters for saving our lives. My friend added that these people really loved and respected the Sangai deer. They believed that killing the Sangai was an unpardonable sin. According to a Meitei legend, the Sangai are the link between humans and nature. So, killing us would mean breaking a bond. My friend informed me that people concerned about animals like us have formed a group. They teach others to protect animals, too.
The news that people are trying their best to save the phumdis, deer like me, and the Loktak Lake, infuse new hope in me. 'How nice of them!' I thought.
Anyway, it is getting dark and my friend and I have to return to our herd. And those of you who are around can enjoy our dancing gait as we trot back home. It would be great if I could meet you again. We could dance together at KLNP, if you can make it here some time!"
The home range of brow-antlered deer in the park is confined to 15–20 km2 (5.8–7.7 sq mi) in the southwestern part of the lake where phumdis on which the deer thrive are abundant. A study conducted on the proportion, on the basis of body weight of stag, hind and fawn, is reported to be 4:2:1. The sangai distribution dictated by shelter and availability of food is high near Toyaching, Pabotching and the Yang Kokchambi area.[19]
Censuses conducted by the wildlife wing of the Forest Department in 1975, 1990, 2000, and 2003 have shown the Eld's deer population was 14, 76, 162 and 180, respectively. The 2000 survey of 162 deer included 54 stags, 76 hinds and 32 fawns.[19][20] The reports of 2004 indicate a figure of 182 as referred in another section here, which shows the subspecies in Manipur is on the rise.
A successful captive breeding programme is underway at the Alipore Zoological Gardens in Kolkata, and many specimens of the deer have been bred here.[14][15]
For the protection of the thiamin subspecies of the Eld's deer, Chatthin Wildlife Sanctuary and Shwesettaw Wildlife Sanctuary (both protected sanctuaries) and Alaungdaw Kathapa National Park were chosen. Chatthin Wildlife Sanctuary, with an area of 104 sq mi (269.4 km2) in Myanmar's central plains, 125 sq mi (323.7 km2) northwest of the city of Mandalay, has Indaing deciduous broadleaf forest dominated by Dipterocarpus tuberculatus and is the habitat for four species of deer: thamin, muntjac (Muntiacus muntjac), hog deer (Axis porcinus), and sambhar (Rusa unicolor). Subject to indiscriminate hunting in the past (till the ownership of guns was controlled after the 1960s), the thamin, highly threatened, now has a population of about 1,000. Initially, the Smithsonian National Zoo acquired a few thamin for observations and subsequently shifted a few to its Conservation and Research Center at Front Royal, Virginia for biological study.[2][21] For a cross–check of the biological studies done at the research center, the Smithsonian Institution selected the Chatthin Wildlife Sanctuary, a protected park. Special studies on the thamin deer were conducted by the conservation scientists headed by Christen Wemmer of the Smithsonian. They gathered details on the biology and survival of the species by duly correlating with the changes that occurred in the ecology of the region of the Chatthin Wildlife Sanctuary. Under the research project study, the ecology of thamin and a series of training courses in biodiversity were organised. The thamin's life cycle studies on 11 male and eight female radio–collared deer, supported by field studies by the scientists, revealed:[21]
Smithsonian National Zoological Park, which has been closely associated with the preservation of the thamin deer, has in its conclusive observations stated:[22]
"Chatthin Wildlife Sanctuary (CWS) in Myanmar (Burma) protects the largest population of the endangered Eld's deer left in the world. It also represents one of the largest remaining patches of dipterocarp forest–a dry forest that is one of the most threatened and least protected forest types globally. Local people rely on these forests for their livelihood. The forests provide wood, food, shelter, and medicine. Restricting people's access to these forests by declaring them protected is probably not a sustainable solution and will put greater burden on lower income households potentially increasing poverty. However, if people continue to use and abuse forests unregulated they will disappear and with them the Eld's deer and many other species."
With external funding for such protection drying up, though, the efforts had not yielded encouraging results and the conclusion was the conditions were not conducive even to protect the protected parks given the political and funding situation in the country.
The picture is not encouraging in Cambodia, Laos and Vietnam, either. The Burmese brow-antlered deer is 'Near Threatened' and still occurs in reasonable numbers.
The situation of protected areas for the Eld's deer is much worse in Thailand and along its border areas with Laos and Cambodia; it is feared that it may be difficult to prevent the "decline and likely extirpation of Eld's deer from the wild in Thailand".[2]
In Cambodia, Laos and Vietnam, Eld's deer was hunted for the traditional medicinal trade (particularly of this subspecies) and to meet demand for captive animals (especially from zoos) and forest habitat was degraded (deforested) to meet agriculture and infrastructural developments. The subpopulation in Hainan considered as a subspecies by Chinese conservationists was almost extinct in the wild.[2]
In the Savannakhet Province of Laos, conservation efforts centred around community management caused the local population to increase from 80 to 170. A 130,000 hectare National Eld's Deer Sanctuary was created in the area.[23]
In over 200 recent years of known history, the number of this species has declined substantially. Based on estimated rates of the decline of this species assessed in three generations (supposed to be at least a 15-year period) for all the species, the average value is reported to be in excess of 50%. Based on this assessment, IUCN has categorised the species as Endangered. In this assessment for determining the species-level, the numbers in India were considered to be numerically small (also found to be increasing), hence the numbers of wild populations only of Eld's deer P. e. thamin in Myanmar and P. e. siamensis of Cambodia, Laos and Vietnam were considered. The decline in population has been mainly attributed to hunting. In the case of the Myanmar thamin, the decline is discernible but not striking. The categorization is considered a middle-ground situation considering the extensively diverse conditions and conservation trends in the geographically isolated and distinct populations of this species.[2][16]
Female Eld's deer are generally found alone or in pairs with their young, but during the mating season, females and their young gather in herds of up to 50 individuals. Males also move around singly except during mating season. When rutting takes place, males compete with each other to gain control of a harem of females with which they can then mate. After a long gestation period, normally a single calf is born. The young have white spots at birth which fade away as they grow; they are weaned at seven months of age, and become sexually mature from 18 months of age onwards. The gestation period for three species is 220 to 240 days, with birthing occurring:.[2][16][17]
In India, the Eld's deer sangai subspecies is confined to the peculiar floating bog called Phumdis in Loktak Lake and is numbered at less than a few hundred animals. The subspecies P. e. siamensis, which occupied the vast monsoon forests from Thailand to Hainan was extinct in Thailand, very few in number in Laos and Cambodia, and almost extinct in Vietnam. A few hundred deer were protected in a large enclosure in Hainan Island, China.[2][14][21] The estimated figures are:
In 2003, the estimated number of captive animals of the three subspecies in zoos were[2] 180 P. e. eldii, 1100 P. e. thamin and 23 P. e. siamensis.
Peculiarities to each subspecies include:[2]
Some observations on the habits of Eld's deer common to all three subspecies are a) active most of the time, seek shelter from the midday sun and migrate for short periods seeking water in the dry season and food in the growing season, b)seek areas that are seasonally burned in search of new grasses that grow after the burn, c) their diets comprise a variety of grasses, herbaceous plants, and shoots, grasses, fruit and wetland plants and they poach into cultivated crops to graze and browse in nearby fields of rice, lentils, maize, peas and grapes.[2][14][15][24]
Thamin are prized as game by hunters due to their impressive antlers and hides that are in demand in local markets. They are also widely hunted for food; they were believed to have been used to feed armies during many Asian wars. Their population has additionally declined due to intense development activities necessitating reclamation of land for grazing, cultivation and fish farming within their range. In Myanmar, deforestion of the diperocarp forests is cited as a reason for the threat faced by the thamin deer. The habitat available for their protection is very limited; only 1% of the protected forests are suitable for its protection in South Asia. Even in protected areas, the animals are poached. Another striking problem is finding adequate funds and political will to protect the species. The species have a fragmented distribution and are therefore at risk from inbreeding and loss of genetic variation.[14] The film The Return of Sangai is a documentary by George Thengummoottil about the species in Keibul Lamjao National Park.
Rucervus eldii eldii
From Disney's Animal Kingdom
From Disney's Animal Kingdom
Skull of brow-antlered deer, Rucervus eldii, Natural History Museum Leiden
Prague zoo
Prague zoo
Prague zoo
Prague zoo
Prague zoo
{{cite journal}}: CS1 maint: multiple names: authors list (link) {{cite web}}: CS1 maint: unfit URL (link) Eld's deer (Rucervus eldii or Panolia eldii), also known as the thamin or brow-antlered deer, is an endangered species of deer endemic to South Asia and Southeast Asia.
