Blog

Discover the Nilgiri Marten’s habitat, behaviour, conservation status, identification, and the best places to see this rare Western Ghats mammal.

Part 1

Nilgiri Marten (Martes gwatkinsii): India’s Most Elusive Forest Predator

Among India’s mammals, few are as little known as the Nilgiri Marten (Martes gwatkinsii). Endemic to the Western Ghats, it is the country’s only marten species and one of its rarest carnivores. Even experienced wildlife researchers can spend years working in suitable habitat without seeing one in the wild. Despite its rarity, recent field studies and habitat modelling have improved our understanding of where it lives, how it survives, and why its conservation deserves greater attention.

For wildlife travellers, spotting a Nilgiri Marten is never something that can be planned with confidence. Unlike tigers or elephants, it cannot be tracked on regular safaris, and sightings are usually brief and unexpected. However, learning about its ecology offers a deeper appreciation of the unique shola forests and montane landscapes of the Western Ghats, where many of India’s endemic species have evolved over millions of years.

This guide brings together current research, practical wildlife travel advice, and conservation insights to help readers understand one of India’s most elusive mammals.

What Is the Nilgiri Marten?

The Nilgiri Marten belongs to the weasel family (Mustelidae), a diverse group that also includes otters, badgers, polecats, ferrets, and weasels. Within this family, martens are agile forest-dwelling carnivores known for their climbing ability and varied diets.

Unlike the several marten species found across Europe, North America, and northern Asia, the Nilgiri Marten is found only in the Western Ghats of southern India. This restricted range makes it one of India’s true endemic mammals and an important indicator of healthy montane forest ecosystems.

Although it remains poorly studied compared to larger mammals, recent research suggests that suitable habitat extends across parts of Kerala, Tamil Nadu, and Karnataka, including both protected forests and adjoining multi-use landscapes. This has changed how conservationists view the species and highlights the importance of protecting habitat beyond national parks alone.

Quick Facts

Why the Nilgiri Marten Matters

Large mammals often receive most of the conservation attention in the Western Ghats, but smaller carnivores play equally important ecological roles. As a predator of rodents, birds, reptiles, insects and other small animals, while also feeding on fruits, the Nilgiri Marten occupies a unique position within the forest food web. Its varied diet means it may contribute both to regulating prey populations and to seed dispersal, although aspects of its ecological role remain under study.

The species also serves as an indicator of landscape health. Because it depends on connected forest habitats, its presence often reflects the quality of the surrounding ecosystem. Recent habitat modelling suggests that a substantial proportion of suitable habitat lies outside protected areas, making conservation in plantations, forest corridors and other multi-use landscapes increasingly important.

How to Identify a Nilgiri Marten

Correct identification is important because the Nilgiri Marten is frequently confused with civets or mongooses, especially during brief roadside or forest sightings.

Several features help distinguish it.

• A long, slender body adapted for climbing.
• Rich dark brown to blackish fur over most of the body.
• Reddish-brown colouring on the neck and shoulders.
• A large yellow to orange throat patch that stands out clearly.
• A long, bushy tail that provides balance while moving through trees.
• Rounded ears and a pointed muzzle typical of martens.

The bright throat patch is often the easiest field mark, particularly when the animal pauses or climbs. Unlike civets, the Nilgiri Marten lacks bold body spots or stripes, and its movement is more agile and weasel-like. Researchers also note that it is an accomplished climber, spending considerable time in trees while foraging or travelling through forest canopies.

Expert Tip

If you briefly spot a dark mammal with a vivid yellow throat moving confidently through trees in a high-elevation Western Ghats forest, you’re more likely looking at a Nilgiri Marten than a civet. The combination of its throat patch, bushy tail and active climbing behaviour is one of the best field identification clues.

End of Part 1.

                              Part 2

Distribution and Habitat

The Nilgiri Marten has one of the smallest natural ranges of any carnivore in India. It is found only in the Western Ghats, a mountain chain that stretches from Gujarat to Kerala but contains suitable habitat for the species only in its southern and central sections. Its distribution is patchy rather than continuous, with populations occupying isolated forest blocks separated by valleys, plantations and human settlements. This fragmented range is one of the reasons the species remains vulnerable despite occurring across three states.

Unlike wide-ranging predators that can adapt to many environments, the Nilgiri Marten is closely associated with cool, moist forests at higher elevations. Even within the Western Ghats, suitable habitat is limited to specific landscapes where forest structure, food availability and connectivity meet its ecological requirements.

Where Is the Nilgiri Marten Found?

Confirmed records come primarily from the Western Ghats of:

• Kerala
• Tamil Nadu
• Karnataka

Over the years, sightings have been reported from several important mountain ranges, including:

• Nilgiri Hills
• Anamalai Hills
• Cardamom Hills
• Brahmagiri Hills
• Pampadum Shola National Park
• Gudalur landscape
• Parts of the Nilgiri Biosphere Reserve

Many of these records come from scientific surveys, camera traps and opportunistic observations rather than regular wildlife tourism. Because sightings are infrequent, the known distribution continues to evolve as researchers gather new evidence from previously unsurveyed forests.

The Importance of Shola Forests

The Nilgiri Marten is strongly associated with the distinctive shola–grassland ecosystem of the southern Western Ghats.

This landscape consists of:

• Dense evergreen forest patches occupying valleys and depressions.
• Rolling montane grasslands covering surrounding hilltops.
• Cool temperatures throughout much of the year.
• High rainfall and persistent moisture.

These forests provide several advantages:

• Large trees suitable for climbing.
• Dense canopy cover.
• Abundant prey.
• Seasonal fruit resources.
• Relatively low levels of human disturbance in protected areas.

Shola forests also support many of India’s endemic plants, birds, amphibians and mammals. The Nilgiri Marten shares this habitat with species such as the Lion-tailed Macaque, Nilgiri Langur, Nilgiri Tahr, Malabar Giant Squirrel and numerous endemic birds, reflecting the exceptional conservation importance of these montane forests.

It Doesn’t Live Only Inside National Parks

One of the most significant findings from recent research is that the Nilgiri Marten cannot be conserved by protecting national parks alone.

Species distribution modelling indicates that around 62% of suitable habitat lies outside protected areas, often within landscapes that include tea, coffee, cardamom and wattle plantations interspersed with forest fragments. This challenges the long-held assumption that the species depends exclusively on pristine forests.

Researchers have documented Nilgiri Martens moving through:

• Tea estates bordering forests.
• Coffee plantations with native shade trees.
• Cardamom plantations.
• Forest edges.
• Connected woodland corridors.

These observations suggest that some modified landscapes can function as movement corridors, provided they retain sufficient tree cover and remain connected to natural forests.

However, plantations should not be viewed as substitutes for intact forests. They may allow movement and occasional foraging, but they generally cannot replace the ecological complexity of mature evergreen forests that support breeding populations.

Field Note: A Nilgiri Marten seen crossing a plantation does not necessarily indicate that plantations are ideal habitat. In many cases, the animal may simply be travelling between larger forest patches.

Habitat Modelling Has Changed What We Know

For decades, knowledge of the Nilgiri Marten’s range was based largely on scattered sightings. Recent studies have improved this picture using species distribution modelling, particularly the MaxEnt approach.

Rather than relying solely on observed locations, researchers combined verified records with environmental variables such as:

• Elevation.
• Rainfall.
• Forest cover.
• Temperature.
• Vegetation characteristics.

The resulting model identified approximately 8,900 km² of suitable habitat across the southern Western Ghats. More importantly, it revealed that a substantial proportion of this habitat occurs beyond the boundaries of protected areas, highlighting the need for landscape-level conservation rather than isolated reserve management.

These findings have practical implications:

• Forest corridors become more valuable.
• Private landowners gain an important role in conservation.
• Plantation management practices can influence habitat quality.
• Infrastructure projects require careful ecological planning to maintain connectivity.

Why Habitat Connectivity Matters

The Nilgiri Marten is unlikely to thrive in small, isolated forest patches over the long term.

Road construction, expanding settlements, hydropower projects and agricultural development can divide forests into disconnected fragments. As these fragments become increasingly isolated, animals may struggle to:

• Find mates.
• Disperse into new territories.
• Maintain healthy genetic diversity.
• Access seasonal food resources.

Connectivity between forests therefore becomes just as important as the protection of individual reserves. Continuous or linked habitats allow wildlife to move naturally across the landscape and reduce the long-term risks associated with isolated populations.

Habitat Comparison

Decision Guide: Where Should Wildlife Travellers Look?

Travellers hoping to glimpse a Nilgiri Marten should set realistic expectations.

Your chances improve if you:

• Visit high-elevation evergreen forests.
• Spend time in landscapes with extensive forest cover.
• Explore areas where researchers have documented previous sightings.
• Join experienced naturalists familiar with local wildlife.
• Stay in the field during early morning or late afternoon, when martens are generally more active.

Even under ideal conditions, sightings remain uncommon. For most visitors, learning about the species and the specialised habitats it depends on is likely to be the most rewarding part of the experience.

End of Part 2.

Part 3

Behaviour and Ecology

The Nilgiri Marten is one of the least-studied carnivores in India. Much of what researchers know comes from opportunistic sightings, camera-trap images and a handful of dedicated field studies rather than decades of continuous observation. As a result, some aspects of its behaviour remain uncertain, and new research continues to refine our understanding.

Even so, existing evidence paints the picture of an agile, intelligent predator that spends much of its time moving through the forest canopy while also foraging on the ground. Unlike many small carnivores that specialise in a narrow range of prey, the Nilgiri Marten is an adaptable feeder capable of exploiting whatever seasonal resources are available.

Is the Nilgiri Marten Active During the Day?

Unlike many members of the weasel family, the Nilgiri Marten is not strictly nocturnal.

Field observations indicate that it is primarily diurnal to crepuscular, meaning it is often active during daylight hours, particularly in the early morning and late afternoon. Researchers have also recorded daytime sightings, which partly explains why occasional encounters occur along forest roads and trekking routes rather than exclusively after dark.

Activity patterns may vary depending on:

• Season
• Weather
• Food availability
• Human disturbance
• Local habitat conditions

This flexibility is common among carnivores living in mountainous forests, where environmental conditions change rapidly.

A Skilled Climber

One of the Nilgiri Marten’s defining characteristics is its climbing ability.

Its long body, flexible spine, sharp claws and bushy tail allow it to move confidently through trees while maintaining balance on branches. Researchers frequently describe it as semi-arboreal, meaning it divides its time between the forest floor and the canopy.

Tree climbing offers several advantages:

• Access to nesting birds.
• Opportunities to hunt squirrels and other arboreal mammals.
• Escape from larger predators.
• Access to seasonal fruits.
• Efficient travel through connected forest canopies.

Although it spends considerable time above the ground, it also travels extensively along fallen logs, rocky slopes and forest trails while searching for food.

What Does the Nilgiri Marten Eat?

The Nilgiri Marten is an opportunistic omnivore with strong carnivorous tendencies.

Rather than relying on a single prey species, it consumes a wide variety of foods depending on season and local availability.

Its diet includes:

• Small mammals
• Rodents
• Birds
• Bird eggs
• Lizards
• Frogs
• Large insects
• Fruits
• Other invertebrates

Fruit becomes particularly important when animal prey is less abundant. This varied diet allows the species to cope with seasonal changes in food availability while occupying a relatively small geographic range.

Why Fruit Matters

At first glance, fruit may seem unusual for a member of the weasel family.

However, many martens around the world supplement their diets with berries and other fruits when available. By consuming fruit and later dispersing seeds, the Nilgiri Marten may contribute to forest regeneration, although the extent of this ecological role has not yet been fully quantified.

Hunting Behaviour

The Nilgiri Marten relies more on agility than brute strength.

It typically hunts by:

• Searching actively through vegetation.
• Investigating tree cavities.
• Climbing between branches.
• Exploring fallen logs.
• Moving quietly along forest edges.

Its slender body allows it to reach prey hidden in places that larger predators cannot access.

Unlike pack-hunting carnivores such as wolves or dholes, Nilgiri Martens usually hunt alone or in small family groups.

Social Behaviour

Very little is known about the social organisation of this elusive species.

Most sightings involve:

• Single individuals.
• Pairs.
• Occasionally small family groups.

There is no evidence that Nilgiri Martens form large social groups similar to dholes or primates.

Like many mustelids, they are thought to maintain individual home ranges, although the size of these territories remains poorly understood because long-term tracking studies are still limited.

Field Note: Some of the most memorable Nilgiri Marten observations involve pairs moving rapidly through the canopy, communicating with one another before disappearing into dense forest within seconds.

Reproduction and Life Cycle

Compared with larger Indian mammals such as tigers, elephants or leopards, very little has been published about the breeding biology of the Nilgiri Marten.

Researchers believe that many aspects of its reproductive behaviour remain undocumented in the wild.

Important knowledge gaps include:

• Courtship behaviour.
• Breeding season.
• Gestation period.
• Litter size.
• Juvenile survival.
• Age at sexual maturity.
• Longevity in the wild.

This lack of information reflects how rarely the species is encountered rather than a lack of scientific interest. Studying an elusive carnivore living in dense montane forests presents obvious logistical challenges, making every confirmed observation valuable.

Ecological Role

Although small compared with India’s large predators, the Nilgiri Marten performs several important ecological functions.

These include:

• Regulating populations of small mammals.
• Controlling certain reptiles and amphibians.
• Feeding on insects.
• Potentially dispersing seeds after eating fruit.
• Contributing to the balance of forest food webs.

Because it occupies a middle position in the ecosystem, changes in its population may reflect broader changes in forest health.

Why Scientists Still Have So Many Questions

The Nilgiri Marten remains one of India’s least understood mammals.

Several factors make research difficult:

• Naturally low population density.
• Extremely elusive behaviour.
• Dense, inaccessible mountain forests.
• Large areas receiving limited scientific surveys.
• Brief and unpredictable sightings.

Recent advances such as camera traps, GPS mapping and habitat modelling have significantly improved knowledge of its distribution. However, researchers continue to identify major gaps in understanding its ecology, movement patterns and population dynamics. Filling these gaps will be essential for developing effective conservation strategies.

Expert Tip

If you’re fortunate enough to encounter a Nilgiri Marten, resist the urge to follow it. These animals move quickly and naturally avoid prolonged contact with humans. Watching quietly from a distance not only minimises disturbance but also gives you a better chance of observing natural behaviour.

End of Part 3.

Part 4

Best Places to See the Nilgiri Marten

Seeing a Nilgiri Marten in the wild is more a matter of luck than careful planning. Unlike flagship species such as tigers or Asiatic elephants, there are no dedicated safaris or wildlife drives focused on this elusive carnivore. Most confirmed observations come from researchers, experienced naturalists and long-term monitoring projects rather than routine tourism.

That said, a handful of landscapes consistently produce more records than others. These areas combine suitable habitat, long-term scientific monitoring and relatively intact montane forests.

Pampadum Shola National Park, Kerala

If one location is most closely associated with the Nilgiri Marten, it is Pampadum Shola National Park.

Although one of Kerala’s smallest national parks, it supports high-quality shola forest habitat and has been the focus of dedicated research. An intensive field study spanning 148 days recorded 42 independent Nilgiri Marten sightings, making it one of the best-studied populations currently known. This does not mean visitors should expect frequent encounters, but it demonstrates the importance of the park for the species.

For wildlife enthusiasts, Pampadum Shola offers another advantage: even without seeing a Nilgiri Marten, the surrounding landscape showcases one of the finest remaining examples of the shola–grassland ecosystem.

Nilgiri Hills

The Nilgiri Hills have long been associated with the species and continue to produce occasional sightings.

This landscape includes a mosaic of:

• Montane evergreen forests.
• Shola patches.
• Grasslands.
• Tea estates.
• Protected reserves.

Recent reports from the Ooty region have highlighted that Nilgiri Martens sometimes move surprisingly close to human-modified landscapes, particularly where forest connectivity remains intact. These sightings reinforce the importance of conserving habitat corridors beyond protected forests.

Anamalai Hills

The Anamalai landscape contains extensive evergreen forests, high rainfall and relatively continuous habitat, making it another important stronghold.

Researchers have documented the species from parts of this mountain range, although sightings remain uncommon. For wildlife travellers, the Anamalais offer the additional attraction of supporting several other Western Ghats endemics, making them rewarding destinations even if a Nilgiri Marten remains unseen.

Cardamom Hills

The Cardamom Hills illustrate an important conservation lesson.

Here, natural forests exist alongside cardamom plantations and other cultivated landscapes. Records from this region suggest that Nilgiri Martens sometimes use plantation–forest mosaics when sufficient tree cover and connectivity are maintained.

These observations underline the value of wildlife-friendly land management in landscapes where agriculture and conservation coexist.

Brahmagiri Landscape

Located near the Karnataka–Kerala border, the Brahmagiri region forms another part of the species’ known range.

Its evergreen forests contribute to landscape connectivity across the Western Ghats and support a variety of endemic wildlife. Although tourist sightings are rare, records from this area help demonstrate that the Nilgiri Marten’s distribution extends beyond a few isolated parks.

Where Are You Most Likely to See One?

Why Sightings Remain So Rare

Even in suitable habitat, several factors work against seeing a Nilgiri Marten.

These include:

• Naturally low population density.
• Large home ranges.
• Excellent camouflage.
• Fast, agile movement.
• Dense forest vegetation.
• Limited time spent in open areas.

Unlike large herbivores that often feed in clearings, Nilgiri Martens spend much of their time within the forest interior, where visibility is poor. Many encounters last only a few seconds before the animal disappears into the canopy or thick undergrowth.

For this reason, experienced naturalists often consider any confirmed sighting a memorable bonus rather than an expected outcome of a visit.

Wildlife Photography Tips

Photographing a Nilgiri Marten is among the most challenging wildlife photography opportunities in India.

The species is:

• Fast-moving.
• Usually observed in low-light forest conditions.
• Frequently partially hidden by vegetation.
• Often visible only for a few moments.

Camera Recommendations

If an opportunity arises:

• Use continuous autofocus.
• Select a fast shutter speed to freeze movement.
• Increase ISO when necessary rather than risking motion blur.
• Keep burst mode enabled.
• Be prepared before entering suitable habitat rather than changing settings after spotting the animal.

Long telephoto lenses are helpful, but patience and quick reactions matter even more.

Photography Tip

Many successful Nilgiri Marten photographs are environmental portraits showing the animal within its forest habitat rather than tightly cropped close-ups. Including branches, moss-covered trees or shola vegetation helps tell the ecological story of the species.

Responsible Wildlife Tourism

Because Nilgiri Martens are so rarely encountered, every observation has scientific and conservation value.

If you see one:

• Stay where you are.
• Avoid blocking its path.
• Do not attempt to follow it through the forest.
• Never use playback calls or bait.
• Avoid flash photography if possible.
• Keep conversations quiet.
• Allow the animal to move away naturally.

These simple actions reduce stress and help ensure that future visitors and researchers can observe natural behaviour rather than animals disturbed by repeated human attention.

How Visitors Can Help Conservation

Wildlife travellers can contribute in meaningful ways without handling animals or participating in research projects.

You can:

• Report confirmed sightings to the relevant Forest Department or research organisations.
• Record the approximate location, date and time.
• Take photographs only if they can be obtained without disturbance.
• Note behaviour and habitat conditions.
• Support conservation organisations working in the Western Ghats.
• Choose responsible eco-lodges that value habitat protection.

Reliable sighting records remain valuable because the Nilgiri Marten is still incompletely surveyed across much of its range. Carefully documented observations may improve understanding of its distribution over time.

Practical Checklist for Reporting a Sighting

If you are fortunate enough to observe a Nilgiri Marten, try to record:

• Date and time.
• General location (avoid sharing precise GPS coordinates publicly).
• Habitat type.
• Number of individuals.
• Behaviour observed.
• Photographs, if safely possible.
• Weather conditions.
• Nearby human activity.

This information can be valuable to researchers while avoiding unnecessary disturbance or public disclosure of sensitive locations.

End of Part 4.

Part 5

Interesting Facts About the Nilgiri Marten

Despite being one of India’s least-known mammals, the Nilgiri Marten has several characteristics that make it unique among the country’s carnivores.

It Is India’s Only Marten

While martens occur across Europe, North America and Asia, the Nilgiri Marten is the only representative of the genus Martes in India. It is also the southernmost naturally occurring marten in the world, making it evolutionarily distinct within the mustelid family.

It Exists Nowhere Else on Earth

The species is endemic to the Western Ghats, meaning its entire global population is restricted to this mountain range. Protecting its habitat therefore contributes directly to the survival of the species worldwide.

Bright Colours Help Identify It

Unlike most Indian small carnivores, the Nilgiri Marten has a striking yellow to orange throat patch against a dark brown body. This feature is often the quickest way to distinguish it from civets or mongooses during a brief sighting.

It Can Live Beyond Protected Areas

One of the most important recent discoveries is that much of the species’ suitable habitat occurs outside national parks and wildlife sanctuaries. Carefully managed plantation landscapes and forest corridors can therefore play a meaningful role in its conservation, provided they remain connected to natural forests.

It Remains One of India’s Least-Studied Carnivores

Compared with tigers, leopards or even smaller mammals such as otters, remarkably little is known about the Nilgiri Marten’s breeding biology, population dynamics and ecology. Every well-documented observation contributes to improving scientific understanding.

Common Mistakes People Make

Understanding what not to assume about the Nilgiri Marten is just as important as knowing its natural history.

Assuming It Is Easy to Find

The Nilgiri Marten is among India’s most elusive mammals. Even experienced researchers working in suitable habitat may go months without seeing one.

Believing It Lives Only Inside Protected Areas

Recent habitat modelling has shown that a significant proportion of suitable habitat occurs in multi-use landscapes outside protected forests. Conservation therefore extends beyond national parks.

Confusing It with Civets or Mongooses

Brief sightings often lead to misidentification. The bright throat patch, bushy tail and agile climbing behaviour are the most reliable field characteristics.

Following or Chasing a Sighting

Attempting to get closer for photographs or videos can disturb the animal and reduce the scientific value of natural observations.

Sharing Exact Locations Online

Publishing precise locations of rare wildlife can unintentionally increase disturbance or create conservation risks. General locality information is usually sufficient for public posts, while detailed records should be shared privately with researchers or forest authorities.

Frequently Asked Questions

Is the Nilgiri Marten endangered?

The Nilgiri Marten is currently classified as Vulnerable on the IUCN Red List, reflecting its restricted range, fragmented habitat and continuing conservation challenges.

Where is the Nilgiri Marten found?

It occurs only in the Western Ghats of Kerala, Tamil Nadu and Karnataka, mainly in montane evergreen and shola forests.

Is it India’s only marten?

Yes. The Nilgiri Marten (Martes gwatkinsii) is the only marten species native to India.

How many Nilgiri Martens remain?

Reliable population estimates are difficult because of the species’ elusive nature. Published assessments suggest fewer than 1,000 mature individuals, but this should be treated as an estimate rather than an exact count.

Why is it so rarely seen?

Its low population density, secretive behaviour, dense forest habitat and large home ranges all contribute to the rarity of sightings.

What does it eat?

Its diet includes small mammals, birds, reptiles, insects and seasonal fruits, making it an adaptable omnivorous carnivore.

Is the Nilgiri Marten nocturnal?

Not entirely. Research suggests it is primarily diurnal to crepuscular, although activity patterns may vary between locations and seasons.

Can tourists see one on safari?

There are no safaris dedicated to the Nilgiri Marten. Sightings are always unpredictable and should be regarded as fortunate wildlife encounters rather than expected attractions.

Which national park offers the best chance?

Pampadum Shola National Park is considered one of the most important study sites because repeated scientific observations have been recorded there. However, sightings remain uncommon for visitors.

Can it survive in plantations?

Research indicates that the species may use plantation landscapes connected to natural forests, but intact evergreen forests remain its primary habitat.

What are its biggest threats?

Habitat fragmentation, land-use change, infrastructure development and the loss of forest connectivity are considered among the most significant threats.

How can travellers help conserve the species?

By supporting responsible tourism, respecting wildlife, reporting verified sightings to researchers or forest departments, and encouraging protection of connected forest landscapes.

Conclusion

The Nilgiri Marten may not have the fame of India’s tiger or leopard, but it represents something equally important—a specialised predator found nowhere else on Earth. Restricted to the forests of the Western Ghats, it reflects both the ecological uniqueness of these mountains and the challenges of conserving wildlife in increasingly fragmented landscapes.

Recent research has significantly improved our understanding of the species, revealing that conservation must extend beyond protected areas to include forest corridors and carefully managed multi-use landscapes. At the same time, many aspects of its life history remain unknown, making continued scientific study and responsible citizen reporting especially valuable.

For wildlife travellers, the Nilgiri Marten is best appreciated not as a species to tick off a checklist but as a symbol of the Western Ghats’ hidden diversity. Even if you never encounter one in the wild, exploring its habitat offers the opportunity to experience some of India’s most distinctive forests and to better understand why their conservation matters.