The Himalayan wolf (Canis lupus) is a canine of debated taxonomy. It is distinguished by its genetic markers, with mitochondrial DNA indicating that it is genetically basal to the Holarctic grey wolf, genetically the same wolf as the Tibetan wolf, and has an association with the African golden wolf (Canis anthus). There are no striking morphological differences between the wolves from the Indian Himalayas and those from Tibet. The wolf is found in northern India in the Ladakh region of eastern Kashmir, the Lahaul and Spiti region in the northeastern part of Himachal Pradesh, parts of Uttarakhand and North Sikkim. It is also found in the Himalayan regions of Nepal.
The taxonomic classification of the wolves living in the Himalayas have been referred to as Canis laniger Hodgson 1847, Canis chanco Grey 1863, Canis filchner Matschie 1907, and Canis himalayensis Aggawal 2003.
In 1847, the British naturalist Brian Houghton Hodgson classified a female wolf from Tibet as Canis lupus laniger. In 1907, the German zoologist Paul Matschie classified a wolf skin from Xining in the Qinghai province of China as Canis lupus filchneri. In 1938, the American zoologist Glover Morrill Allen classified Canis lupus filchneri and Canis lupus laniger as taxonomic synonyms for Canis lupus chanco (Mongolian wolf). In the third edition of Mammal Species of the World published in 2005, the American mammalogist W. Christopher Wozencraft listed under the wolf Canis lupus the subspecies Canis lupus filchneri, under which he included as a taxonomic synonym the taxon laniger Hodgson 1847.
The wolves living in the Trans-Himalaya region have unique haplotypes, do not cluster phylogenetically with other grey wolves, were basal to all other wolves and are closer to the jackal. This indicates that these are the descendants of an ancient wolf distribution and the taxonomic classification of Canis himalayensis or Canis lupus himalayensis. are proposed.
The taxonomic reference Mammal Species of the World does not recognize Canis himalayensis, however NCBI/Genbank lists Canis lupus himalayensis. Its lineage shows a 3.9% divergence in the mDNA cytochrome b gene when compared with the Holarctic grey wolf, which may justify it being classified as a distinct species.
|Phylogenetic tree of the extant wolf-like canids with timing in millions of years[a]|
|Blue shading represents the species Canis lupus
DNA sequences can be mapped to reveal a phylogenetic tree that represents evolutionary relationships, with each branch point representing the divergence of two lineages from a common ancestor. On this tree the term “basal” is used to describe a lineage that forms a branch diverging nearest to the common ancestor. An animal's mitochondrial DNA (mDNA) is inherited only from its mother.
The Himalayan wolf is distinguished by its genetic markers, which indicate that it is genetically basal to the Holarctic grey wolf based on mDNA, and on both mDNA and DNA taken from the cell nucleus. Whole genome sequencing indicates that it is the most genetically divergent wolf population.
In 2004, a study compared the mDNA of 27 wolves from the Himalayas and the Tibetan Plateau. The study indicates that there were 5 related haplotypes which formed a clade that is basal to all other wolves. This clade included one sequence from Ladakh in eastern Kashmir, nine from the Spiti Valley in Himachal Pradesh, four from Nepal, and two from Tibet. The study proposes that the Himalayan wolf clade diverged from other canids 800,000 years ago. Seven wolves also from Kashmir did not fall into this clade.
Hodgson (1847) described the Tibetan wolf as C. laniger. A study of the mDNA of the specimen that Hodgson collected was found to fall within the proposed Himalayan wolf clade. However, the 50% likelihood provided by the model on which this study rested provides only weak support for this proposal. A criticism of this study is that it was based on zoo specimens, and it is known that all zoo specimens have been captive-bred, descended from only two females, therefore the study did not provide a representative sample. Additionally, the wolf population in the Kashmir valley is known to have recently arrived in that area.
In 2007, a study compared the mDNA for 18 wolves from the Padmaja Naidu Himalayan Zoological Park near Darjeeling in West Bengal, northern India. The study found that the wolves were basal to all other wolves and formed one haplotype, indicating that they shared a common female ancestor. The study did not ascertain if the zoo specimens were all related. The conclusion supported the 2004 study that the Himalayan wolf differed from other Tibetan wolves. A criticism of this study is that it was based on limited data with no samples collected from the Kashmir valley population, despite suggesting that Kashmir is an area of potential contact of the closely related wolf clades. Instead, the samples were collected from Indian zoos or museum specimens. Additionally, the areas under study are part of the same landscape, and the question of what ecological or behavioral barriers could be facilitating such strict divergence, particularly when no striking morphological differences occur between the wolves from Tibet and Indian Trans-Himalaya, remains unanswered.
In April 2009, the Latin binomen Canis himalayensis was proposed for this clade as a separate species of wolf through the Nomenclature Specialist on the CITES Animals Committee. The proposal was based on one study that relied on only a limited number of museum and zoo samples that may not have been representative of the wild population. The committee recommended against this proposal but suggested that the name be entered into the CITES species database as a synonym for Canis lupus. The committee stated that the classification was for conservation purposes only, and did not "reflect the latest state of taxonomic knowledge". Further fieldwork was called for.
In 2012, a study compared the mDNA from the scats of 2 wolves from remote and widely separated areas in the Upper Dolpa, Nepal and found that these matched the Himalayan wolf. In 2016, a study compared the mDNA from the fecal remains of 4 wild wolves from the Upper Mustang region of the Annapurna Conservation Area, Nepal. The study showed that they fell within the Himalayan wolf clade but formed a separate haplotype to those previously studied.
Relationship with the Tibetan wolf
Studies based on mDNA, and X chromosome and Y chromosome DNA indicate that the Himalayan wolf is genetically the same wolf as the Tibetan wolf. This wolf contrasts with the wolves found in the lower altitudes of Inner Mongolia, Mongolia, and the Xinjiang province of China (Mongolian wolf). A further analysis based on single-nucleotide polymorphisms indicates this wolf possesses a genetic adaptation to help it cope with living in low-oxygen, high-altitude habitats. This adaptation could not be found in the Holarctic grey wolf. Some specimens found from as far away as China and Mongolia also fell within a Himalayan/Tibetan wolf clade, indicating a common maternal ancestor and a wider genetic distribution of this wolf. There was evidence of hybridization with the grey wolf at Sachyat-Ertash in the Issyk-Kul region of Kyrgyzstan, and of introgression from either the grey wolf or the dog into the Himalayan wolf in Nepal.
Relationship with the African golden wolf
Two studies of the mitochondrial genome of both modern and extinct grey wolves (Canis lupus) have been conducted but these excluded the genetically divergent lineages of the Himalayan wolf and the Indian gray wolf. The ancient specimens were radiocarbon dated and stratagraphically dated, and together with DNA sequences a time-based phylogenetic tree was generated for wolves. The study inferred that the most recent common ancestor for all other Canis lupus specimens – modern and extinct – was 80,000 years before present. An analysis of the Himalayan wolf mitochondrial genome indicates that the Himalayan wolf diverged between 740,000—691,000 years ago from the lineage that would become the Holarctic grey wolf.
Between 2011 and 2015, two mDNA studies found that the Himalayan wolf and Indian grey wolf were genetically closer to the African golden wolf than they were to the Holarctic grey wolf. From 2017, two studies based on mDNA, and X-chromosome and Y-chromosome markers taken from the cell nucleus, indicate that the Himalayan wolf is genetically basal to the Holarctic grey wolf. Its degree of divergence from the Holarctic grey wolf is similar to the degree of divergence of the African golden wolf from the Holarctic grey wolf. The Himalayan wolf shares a maternal lineage with the African golden wolf. It possesses a unique paternal lineage that falls between the grey wolf and the African golden wolf. The specimens used in these two studies show the high-altitude range of the Himalayan wolf to include the Himalayas then north across the Tibetan plateau to the Qinghai Lake in Qinghai Province, China. The first study called for the Himalayan wolf to be recognised as the species Canis himalayensis or at least as the subspecies Canis lupus himalayensis. The second study called for a taxonomic review of the wolves inhabiting the Himalayas and Tibet.
In 2018, whole genome sequencing was used to compare members of the genus Canis. The African golden wolf was found to be the descendant of a genetically admixed canid of 72% grey wolf and 28% Ethiopian wolf ancestry. The Ethiopian wolf is native to the Ethiopian Highlands. The Ethiopian wolf does not share the same single-nucleotide polymorphisms that confer hypoxia adaptation with the Himalayan wolf. The adaptation of the Ethiopian wolf to living in high altitudes may occur at other single-nucleotide polymorphism locations. This indicates that the Ethiopian wolf's adaptation has not been inherited by descent from a common ancestor shared with the Himalayan wolf.
It is proposed that the Indian wolf, Himalayan wolf, and African golden wolf represent ancient wolf lineages, with the African golden wolf having colonised Africa prior to the northern hemisphere radiation of the Holarctic grey wolf.
Hodgson described his type specimen as follows:
Lupus laniger. The Changu of the Tibetans. Hab. Tibet. Wolf with long sharp face, elevated brows, broad head, large pointed ears, thick woolly pilage, and very full brush of medial length. Above, dull earthy-brown; below, with the entire face and limbs yellowish-white. No marks on the limbs. Tail concolorous with the body, that is brownish above and yellowish below, and no dark tip. Length 45 in (110 cm). Height 30 in (76 cm). This animal is found all over Tibet.
The British naturalist Richard Lydekker wrote in 1900:
In order to withstand the intense winter cold of the bleak altitudes of which it dwells, and at the same time to harmonise with its physical surroundings, the wolf of Ladak and Tibet has developed a woolly character in its fur, and at the same time has become a much paler animal than ordinary examples of the European race.
The British zoologist Thomas C. Jerdon wrote in 1874 that the Tibetan wolf is larger than the Indian Wolf and known as "chankodi" among the people who live near the Niti Pass on the Tibet/Indian border (Kumaon District, India). Black wolves in Tibet are known locally as "chanko nagpo", and these are considered bolder and more aggressive than the pale coloured variety.
The British naturalist William Thomas Blanford, writing in his The Fauna of British India, Including Ceylon and Burma in 1888, described the variety of wolf found in Ladakh and Tibet as very pale-coloured, with woolly fur, and has generally been distinguished as Canis laniger. There are no striking morphological differences between the wolves from the Indian Trans-Himalayas and those from Tibet.
Morphological appearance of the wolves from different parts of India shows certain dissimilarities. Skulls of the two males from Chumar, Ladakh were measured by Allen (234 and 236 mm), which are the largest for wolves in India, but smaller compared to North American wolves, which can measure up to 290 mm. The wolf from peninsular India appears smaller in size and more brownish in colour, whereas wolves from the Himalayan regions are large and whitish. Peninsular wolf weighs 25 kg on an average, which may be the lowest among all wolves, whereas wolves from the Himalayan region weigh about 35 kg, similar to Tibetan wolves.
The wolves from Upper Mustang, Nepal are characterized by their
distinct white coloration around the throat, chest, belly, and inner part of the legs; woolliness of body fur; stumpy legs; unusual elongation of the muzzle, a muzzle arrayed with closely-spaced black speckles which extend below the eye on to the upper cheeks and ears; and smaller size compared to the European wolf.
Canis lupus pallipes has the smallest skull length, measuring maximum up to 220 mm. Zygomatic widths of the skull of wolves from Ladakh (129 and 128 mm) were also comparatively larger than those of peninsular wolves from India (90.2–109 mm). Upper cheek teeth, i.e. canine to last molar of two wolves from Ladakh measured 105 and 98.4 mm, which is larger compared to those of peninsular wolves and Arabian wolves (93.6–97 mm and 81.3–93 mm respectively).
A comparative study of Himalayan wolves with other grey wolf subspecies howls demonstrated that the Himalayan wolf howls typically had lower frequencies and were shorter in duration. The study found that Himalayan and North African wolves showed the most acoustically distinct howls and differed significantly from each other and to the other wolf subspecies.
The wolf is found in northern India in the Ladakh region of eastern Kashmir and the Lahaul and Spiti region in the northeastern part of Himachal Pradesh. It is also found in the Himalayan regions of Nepal, in the Api Nampa Conservation Area, Upper Dolpa, Holma, Manaslu, Upper Mustang, and the Kanchenjunga Conservation Area. These wolves have been photographed in North Sikkim as well.
The Indian population consists of 350 wolves with a range of 70,000 km2 (27,000 sq mi). In 2004, a group of 33 Himalayan wolves were spotted in the Spiti Valley in the northeastern part of Himachal Pradesh. In the same year, the wolf was spotted for the first time in Nepal in the Upper Mustang region. Between 2005 and 2008, sightings and scat of Tibetan wolves were recorded in the alpine meadows above the tree line north-east of the Nanda Devi National Park in Uttarakhand, India. In 2013, the media reported that a Tibetan wolf was photographed by a camera trap installed at about 3,500 m (11,500 ft) altitude near the Sunderdhunga Glacier in Bageshwar district, Uttarakhand, India.
Himalayan wolves prefer wild over domestic prey. They prefer the smaller Tibetan gazelle than the larger white-lipped deer, and they prefer the plains-dwelling Tibetan gazelle over the cliff-dwelling naur. Supplementary food includes the small Himalayan marmot, woolly hare, and pikas. Himalayan wolves avoided livestock where wild prey is available, however habitat encroachment and the depletion of wild prey populations is forecast to lead to conflict with herders. To protect these wolves it will be important to secure healthy wild prey populations through setting aside wildlife habitat reserves and refuges.
The Indian wolf and the wolves of the Himalayan regions of India are listed under Schedule I of The Indian Wildlife Protection Act, 1972, which bans a zoo from acquiring or transferring a wolf unless it has previous permission from the government. The wolf populations of Bhutan, India, Nepal and Pakistan fall under the CITES Appendix I, which lists the species that are the most endangered among the CITES-listed animals and plants. The Indian Government has banned the export of all wild-taken species that falls under CITES Appendices I, II and III.
The Himalayan wolf is listed as an endangered species in certain areas of Jammu and Kashmir, Himachal Pradesh, and Uttarakhand. A large portion of the wolf population in these areas exists outside of the protected area network, which is alarming for the initiatives of their conservation and suggests that management for conservation in these areas should equally consider the area outside protected areas. Their scarce populations and evolutionary uniqueness have been underlined in some recent studies. Lack of information about their basic ecology in this landscape is a severe hindrance towards a sound conservation plan for these animals.
It has been suggested by several biologists in India for recognition as a critically endangered species of canid. Eighteen Himalayan wolves are being bred in captivity. They were captured in the wild and are now being preserved in the trans-Himalayan region of India, at the Padmaja Naidu Himalayan Zoological Park in Shiwalik Hills on the lower range of the Himalaya in West Bengal, and in the Kufri Zoo with Kufri Himalayan National Park located in Himachal Pradesh province.
The wolves of Nepal are protected under Schedule 1 of The National Parks and Wildlife Conservation Act, 2029 (1973), under which these are regarded as protected wildlife and their hunting prohibited.
The Himalayan wolf is genetically distinct and basal to the Holarctic grey wolf. Its vocalization differs significantly from the Holarctic grey wolf. It shows a genetic high-altitude adaptation that is unique amongst wolves and it continues to exist despite hybridization in the boundary areas around its high-altitude range. Its lineage shows a 3.9% divergence in the mDNA cytochrome b gene when compared with the Holarctic grey wolf, which may justify it being classified as a distinct species. It is a taxon of global conservation concern. Nepal is home to a considerable Himalayan wolf population that exists within its northern arch, an area that is dominated by the inaccessible Himalayan mountains and provides an important habitat refuge for the Himalayan wolf. One study recommends that Nepal takes the leading role in Himalayan wolf conservation.
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- Schedule 1, Part 1, Mammals
- Canis lupus
- Ban on trade in wild fauna and flora
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- Schedule 1