Prionodon pardicolor: The Spotted Linsang detected within the Murlen National Park in Mizoram, India.

The Spotted Linsang, Prionodon pardicolor, is a small, nocturnal, tree-dwelling Carnivoran Mammal found across much of Southeast Asia and neighbouring areas. Together with the Banded Linsang, Prionodon linsang, it makes up the Family Prionodontidae, which has recently been shown to be the sister group to the Felids (African Linsangs, Poiana spp., are more closely related to Civits). The Spotted Linsang is known from Assam, Mizoram, Manipor, Nagaland, Sikkim, Arunachal Pradesh, and Meghalaya states in India, as well as eastern Nepal, northeastern India, Bhutan, northern & central Myanmar, northern and central Thailand, Laos, Cambodia, most of Vietnam, and central to southern China. Because of its wide geographical distribution, it is considered to be of Least Concern under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species, but because of its secretive nature, it is far from clear how abundant this species actually is, nor whether it is threatened by the widespread Human encroachment into forest habitats across much of its range.

In a paper published in the Journal of Threatened Taxa on 26 November 2022, Amit Kumar Bal of the Society for the Preservation of Endangered Carnivores and their International Ecological Study, and the Amity Institute of Forestry and Wildlife at Amity University,  and Anthorny Giordano, also of the Society for the Preservation of Endangered Carnivores and their International Ecological Study, present the first evidence for the presence of the Spotted Linsang within the Murlen National Park in southern Mizoram State, a significant increase in the species known range, and discus the potential impact of Human-Linsang interactions upon the future of the species.

Range extension of the Spotted Linsang further south into northeastern India, added onto the IUCN global distribution map for the species. Bal & Giordano (2022).

The Murlen National Park lies within the Champhai District of Mizoram, and forms part of the Indo-Burman Biodiversity Hotspot. The park covers a range of hilly and mountainous terrains, and includes areas of tropical and subtropical forests. While in theory protected, wildlife in the park is threatened by a number of Human activities, including logging, hunting, Cattle grazing, and the Jhum cultivation (a form of slash-and-burn agriculture).

Bal and Giordano deployed 10 camera traps within the park between November 2019 and May 2022, as part of a wider study into small carnivore populations, and the threats that they face. During this time (over 400 nights of observation), Bal and Giordano captured six images of Spotted Linsangs, an Animal not previously thought to be present within the park. 

Four individuals of Spotted Linsang photographed in Murlen National Park, Mizoram. Bal & Giordano (2022).

During the course of the study, Bal and Giordano also observed the carcass of a Spotted Linsang within the home of a hunter in Murlen. When questioned on the subject, the hunter admitted to having shot the Animal with a hand-held catapult, in the belief that it was a Leopard Cat, several body parts of which can be traded locally. The hunter stated that he did not know what the Spotted Linsang was, and that he had never seen such an Animal before. This specimen was 69 cm in length, 35 cm of which was made up by the tail.

Carcass of a Spotted Linsang observed in the how of a hunter during the study. Amit Kumar Bal in Bal & Giordano (2022).

Camera trap observations, or observations of any kind, are rare for Spotted Linsangs, which makes estimations of their population difficult. This presumably also makes them less prone to being targeted by Human hunters, although they are clearly not immune from this threat. Dead Spotted Linsangs have also been observed by Amit Kumar Bal caught in snare traps in Arunachal Pradesh, a more indiscriminate form of hunting widely practised in India and Southeast Asia. There are also reports of their having been killed for their skins in Arunachal Pradesh, as well as in retribution for their hunting of domestic poultry. Bal and Giordano suggest that the species should be subject to a more detailed study, covering a wider geographical area, to better understand its population structure and the threats it faces from Human encroachments.

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Magnitude 6.2 Earthquake in the India-Myanmar border region.

The Indian National Centre for Seismology recorded a Magnitude 6.1 Earthquake at a depth of 27 km, in the India-Myanmar border region, about 140 km to the southeast of the city of Aizawl in Mizoram State, India, at about 5.15 am local time on Friday 26 November 2021 (slightly after 11.45 pm on Thursday 25 November, GMT). Earthquakes this large and at this shallow a depth are considered to be extremely dangerous, as much energy is being dissipated close to the surface, where it can potentially do the most harm, although on this occasion there are no reports of any damage or casualties. The Earthquake was felt across northern Myanmar, Bangladesh, northeast India, and Bhutan.

 

The approximate location of the 26 November 2021 India-Myanmar border region Earthquake. USGS.

Earthquake activity in northeast India is influenced by the uplift of the Tibetan Plateau, due to the impact of India into Eurasia to the south. The Indian Plate is moving northwards at a rate of 5 cm per year, causing it to impact into Eurasia, which is also moving northward, but only at a rate of 2 cm per year. The collision of the Indian and Eurasian plates has led to the formation of the Himalayan Mountains, the Tibetan Plateau, and the mountains of southwest China, Central Asia and the Hindu Kush.

 

Block diagram showing how the impact of the Indian Plate into Eurasia is causing uplift on the Tibetan Plateau. Jayne Doucette/Woods Hole Oceanographic Institution.

The India-Myanmar border region is an area particularly prone to Earthquakes; much of Myanmar lies on the Burma Plate, a small tectonic plate caught between  the Eurasian Plate to the northeast, the Indian Plate to the west and southwest and the Sunda Plate to the southeast. As these larger plates move together the Burma Plate is being squeezed and fractured, with a major fault line, the Kabaw Fault, having formed across much of the north of the country, along which the Burma Plate is slowly splitting. Most Earthquakes in the region are caused by movement on this fault.

 

The movement of the Burma and surrounding plates. Sheth et al. (2011).

Witness accounts of quakes can help geologists to understand these events and the rock structures that cause them. If you felt this quake you can report it to the Indian National Centre for Seismology here.

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Cuon alpinus: Understanding the distribution of Dholes in northeast India.

The Dhole, or Asian Wild Dog, Cuon alpinus, is an Endangered social carnivore found in forested landscapes of South and Southeast Asia. Historically widespread across Asia, the species’ range has contracted by about 80%. The current distribution extends across most of South and Southeast Asia and parts of China but is largely restricted to protected areas. The protected forest landscapes south of the River Ganges in India are a stronghold for the species, with the largest Dhole population. However, the species has undergone local extirpation across parts of its former range as a result of declines of prey species, loss of habitat and, potentially, disease. Information on Dholes in northeast India in particular is limited, despite the fact that this landscape shares continuous forest with Myanmar and Southeast Asia, forming an important part of the species' global range.

A Dhole, or Asian Wild Dog, Cuon alpinus. David Raju/Wikimedia Commons.

In a paper published in the journal Orynx on 23 October 2019, Priya Singh of Researchers for Wildlife Conservation at the National Centre for Biological Sciences, and the School of Natural Resources and Environment at the University of Florida, Arjun Srivastha of the Department of Wildlife Ecology and Conservation at the University of Florida, and David Macdonald of the Wildlife Conservation Research Unit at the University of Oxford, provide a compilation of dhole presence records from across northeast India using data extracted from multiple sources.

Current knowledge of Dholes in north-east India is restricted to landscapes north of the River Brahmaputra. This is primarily because of the paucity of baseline ecological data from the region, given its undulating terrain, difficulty of access, wet climatic conditions, and socio-political insurgencies.

Using data from camera-trap surveys Singh et al. examine factors influencing fine-scale site-use by Dholes in Dampa Tiger Reserve in Mizoram State. They discuss the implications of their results for Dhole conservation in northeast India, where the focus of wildlife managers is directed mainly towards population recoveries of and local recolonisation by the Tiger, Panthera tigris. They further provide recommendations for management interventions that could facilitate conservation of Dholes in this hitherto neglected landscape.

Dampa Tiger Reserve lies in the Indo-Myanmar Biodiversity Hotspot. The reserve is contiguous with the Chittagong Hill Tract region of Bangladesh to the west. The core area of the Reserve covers 500 km², and the multi-use buffer covers an area of 488 km². The Lushai Hills traverse the reserve, with altitudes of 250-1100 m. Mean annual rainfall is 2000-2500 mm. The Reserve supports a high diversity of Carnivores, including, in addition to the Dhole, four species of Felids and two species of Ursids. In the course of the study Singh et al. also recorded the Elephant, Elephas maximus, Gaur, Bos gaurus, Sambar, Rusa unicolor, Red Serow, Capricornis rubidus, Muntjac, Muntiacus muntjak, and Wild Pig, Sus scrofa.

Northeast India, with the Dampa Tiger Reserve in Mizoram and locations where the Dhole, Cuon alpinus, has been recorded, with corresponding reliability scores. Singh et al. (2019).

Singh et al. compiled Dhole presence records for nine northeastern states: Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim, Tripura, and West Bengal. They searched for records from 1990 onwards in newspaper reports, scientific articles, grey literature (including species checklists), and reports by Forest Department personnel, local informants and naturalists working in the region. For each record they noted the type of evidence (direct/indirect), the date of the sighting, the administrative status of location (protected/non-protected), and the source person or reference. They assigned reliability scores for each record, from 1 to 5, with 1 being most reliable, and 5 least reliable.

From December 2014 to March 2015, Singh et al. deployed 79 pairs of Cuddeback Ambush IR camera traps across 80 km² in the northeast of Dampa Tiger Reserve’s core area. At each station they placed two cameras facing each other, about 30 cm above the ground, on either side of forest trails or on riverbeds. Mean inter-trap distance was 1.02 km, with traps remaining active for an average of 64 days. Although the stations were intended to photograph wild Felids, they also photographed other Carnivores. Dholes generally use forest trails and riverbeds for movement, marking territories and hunting, and our sampling design therefore incorporated areas used by the species.

Singh et al. obtained presence records from 80 locations for 1990-2018, of which we considered 41 records from 2010–2018 with reliability scores of 1-3. In the case of multiple records for the same site, they considered the most recent record with the highest reliability score. Most records were from Arunachal Pradesh (14) and Assam (8), with five records from Mizoram and Nagaland, four from West Bengal, three from Meghalaya and two from Sikkim. There were no recent records of Dholes from Manipur and Tripura. A total of 5033 camera trap-days in Dampa Tiger Reserve generated 500 photoencounters of Dholes, comprising 92 detections (one per 24 hour duration) across 33 sites. 

Singh et al. found photo-capture frequencies of key prey species: Sambar (236), Muntjac (145), Wild Pig (92); to be positive influences, as were the distance to reserve boundary, and photo-capture frequencies of Forest Department personnel, while photo-capture frequencies of other humans were  negative influences on site-use by Dholes.

There are records of Dholes across several areas of northeast India, including in unprotected areas. Previous global assessments indicated that the species faced near or complete local extirpation to the south of the River Brahmaputra, something refuted by Sigh et al.'s findings from Dampa Tiger Reserve. Corroborating current knowledge from other landscapes, showed a positive relationship between Dhole site-use and Sambar presence. Across their extant distribution, the range of Dholes overlaps with that of Tigers and Leopards, Panthera pardus. Wildlife managers in this region and elsewhere subscribe to unsubstantiated notions that dhole presence impedes colonisation by Tigers, and consequently treat Dholes as a problem species. On the contrary, Tigers, Leopards and Dholes can co-exist provided protected areas support adequate densities of medium- to large-sized prey species.

Dampa Tiger Reserve is an important refuge for Dholes in northeast India. It supports large tracts of inviolate protected spaces, and habitat connectivity with forested landscapes of the Chittagong Hill Tract region to the west, Mamit Forest Division to the north and Thorangtlang Wildlife Sanctuary to the south. Singh et al's camera-trap data indicate the presence of a guild of large herbivores in the Reserve, with at least five prey species of medium and large ungulate herbivores, facilitating the long-term persistence of dholes there. The findings re-emphasise the importance of protected areas, which can serve as source sites for sustaining Dhole populations across the region.

In areas with low prey densities, carnivores may have significant dependence on livestock, and are consequently stigmatised. There is a strong negative relationship between Dholes and livestock owners in Arunachal Pradesh and other locations in the region. Given that Dholes also occur outside protected areas in this region, they are potentially vulnerable to retributory killing. Negative interactions between people and Dholes necessitate interventions to reduce poaching and facilitate recovery of prey, especially for species such as Sambar that are impacted by low recovery rates following prolonged poaching. Singh et al.'s findings need to be augmented with a systematic survey across the locations they identified, specifically in the states of Mizoram and Nagaland, to facilitate a pan-northeast India strategy for Dhole conservation.

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Flooding kills 23 in northeastern India.

Twenty three people have died in flooding in northeastern India since the Southwest Monsoon arrived in the area five days ago. Twelve of the deaths occurred in the state of Assam, where five people died on Sunday 17 June alone, with the remaining deaths occurring in Manipur, and severe flooding also reported in Tripura, and Mizoram. Thousands of people across the region have been forced to abandon homes and farms in the region, and it in addition to the Human casualties, large numbers of livestock have died.

Floodwaters in Assam this week. Anuwar Hazarika/Reuters.

Monsoons are tropical sea breezes triggered by heating of the land during the warmer part of the year (summer). Both the land and sea are warmed by the Sun, but the land has a lower ability to absorb heat, radiating it back so that the air above landmasses becomes significantly warmer than that over the sea, causing the air above the land to rise and drawing in water from over the sea; since this has also been warmed it carries a high evaporated water content, and brings with it heavy rainfall. In the tropical dry season the situation is reversed, as the air over the land cools more rapidly with the seasons, leading to warmer air over the sea, and thus breezes moving from the shore to the sea (where air is rising more rapidly) and a drying of the climate.

 Diagrammatic representation of wind and rainfall patterns in a tropical monsoon climate. Geosciences/University of Arizona.

Much of Southeast Asia has two distinct Monsoon Seasons, with a Northeast Monsoon driven by winds from  the South China Sea that lasts from November to February and a Southwest Monsoon driven by winds from the southern Indian Ocean from March to October. Such a double Monsoon Season is common close to the equator, where the Sun is highest overhead around the equinoxes and lowest on the horizons around the solstices, making the solstices the coolest part of the year and the equinoxes the hottest. However northeast India is largely protected from the Northeast Monsoon by the mountains to its north and east, though these can also add to the severity of flooding in the region, with melting snow in the Himalayas swelling the rivers that flow through these states,

The winds that drive the Northeast and Southwest Monsoons in Southeast Asia. Mynewshub.

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Landslip at Mizoram quarry kills four.

Four people, including two minors, have died in a landslip at a quarry on the outskirts of the city of Aizawl in Mizoram State, India. The incident happened at about 7.30 am local time on Saturday 12 May 2018, when the four were working at the quarry, which is reported to be owned by local businessman John Halliday. The deceased have been named as Munga, 40, Linda Zodinpuii, 32, and her daughters Linda Hmingthianghlimi, 14, and Lalremzovi Zodinpuii, 10.

Rescue workers searching the scene of a landslip at a quarry in Aizawl. Mizoram, on 12 May 2018. Henry Khojol/Telegraph India.

Mizoram does not have a well developed mining industry, although it is thought to have deposits of metals, coal and other potentially commercial deposits, as it is remote from the main centres of industry in India, making it hard to export the produce of any large-scale mining operation, and presenting difficulties obtaining reliable power for such an industry. However a number of products are excavated locally, such as sandstone and limestone for use in construction and clay for the ceramics industry. As such mining operations that do exist tend to be small scale, locally owned and poorly regulated, with the industry known to have low safety standards and prone to illegal activities such as unlicensed extraction (which usually also implies no outside safety inspections) and the employment of minors (the employment of children under 14 in the mining industry is illegal in India.

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