Thirty four confirmed dead and many more still missing following landslide in West Java.

Thirty four people have been confirmed dead and 56 are still missing following a landslide which hit the village of Pasirlangu on the side of Mount Burangrang in West Java Province, Indonesia, on Saturday 24 January 2026. As well as local villagers, the landslide is reported to have hit a group of Indonesian marines on a training exercise in the area, who are thought to have been wiped out. So far the bodies of four marines have been recovered, with another nine still missing. 

A rescue team searching the site of a landslide which hit the village of Pasirlangu in West Java on 24 January 2026. Septianjar Muharam/Xinhua.

The landslide is reported to have been triggered by heavy rains associated with the northeast monsoon. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. However, the root cause of the landslide appears to have been deforestation, with a large area of forest above the village cleared to create space for commercial vegetable farming. This process removes the root structure which binds soil together, making slopes more vulnerable to slippage, particularly in areas such as West Java, where soils tend to be volcanic, as such soils typically have much smaller particle sizes and lose cohesion more rapidly when they become waterlogged.

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 seasons, 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.

Java 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.

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

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Eruption on Mount Semeru.

People living close to Mount Semeru, a 3676 m high stratovolcano (cone-shaped volcano made up of layers of ash and lava) close to the city of Lumajang in East Java, have been advised to avoid going near the volcano, following an eruption on Wednesday 19 November 2025. The volcano began erupting at about 4.00 pm local time (about 9.00 am GMT) producing an ash column about 5.6 km high, and triggering a series of pyroclastic flows (avalanches of hot rock, ash and gas) which reached as far as 7.00 km from the volcano.

A column of Ash above Mount Semeru on 19 October 2025. Badan Geologi/AP.

Mount Semeru forms part of the Tengger Volcanic Complex is a string of five overlapping stratovolcanoes (cone-shaped volcanoes) forming a single massif, extending northward from Semeru. The whole massif sits within a vast caldera (volcanic crater), left by the explosion of an ancient volcano about 150 000 years ago. The volcanoes are at the center of this caldera, surrounded by a vast sea of sand, the Tengger Sand Sea.

The approximate location of Mount Semeru. Google Maps.

The Indo-Australian Plate, which underlies the Indian Ocean to the south of Java, is being subducted beneath the Sunda Plate, a breakaway part of the Eurasian Plate which underlies Java and neighbouring Sumatra, along the Sunda Trench, passing under Java, where friction between the two plates can cause Earthquakes. As the Indo-Australian Plate sinks further into the Earth it is partially melted and some of the melted material rises through the overlying Sunda Plate as magma, fuelling the volcanoes of Java and Sumatra.

Subduction along the Sunda Trench. Earth Observatory of Singapore.

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Panthera tigris sondaica: A possible sighting of the 'extinct' Javan Tiger.

Indonesia was once home to three species of Tiger, the Sumatran Tiger, Panthera tigris sumatrae, the Javan Tiger, Panthera tigris sondaica, and the Bali Tiger, Panthera tigris balica. Two of these species  have been declared extinct in the past twenty years, the Javan Tiger in 2008, and the Bali Tiger in 2013, using the International Union for the Conservation of Nature's criteria of not having been observed in more than 30 years; the last confirmed sighting of a Javan Tiger happened in 1976 in Meru Betiri National Park, East Java.

The Javan Tiger was endemic to Java, and in the eighteenth and nineteenth centuries was frequently encountered in lowland forests, thickets, and even gardens on the island. However, it was widely seen as a pest (Tigers will feed on both livestock and Humans), leading to widespread hunting of the species, and its presumed extinction in the last quarter of the twentieth century. The last systematic search for the species deployed 35 camera traps in the Meru Betiri National Park in 1999-2000, but made no observations.

A Javan Tiger observed in Ujung Kulon Nature Reserve (now Ujung Kulon National Park) in 1938. Andries Hoogerwerf/Wikimedia Commons.

Although there have been no confirmed sightings since 1976, rumours of the species' continued existence persist, with numerous unconfirmed sightings, reports of footprints too large to belong to a Leopard, and even reports of attacks on livestock. 

In a paper published in the journal Oryx on 21 March 2024, Wirdateti Wirdateti of the Research Center for Biosystematics and Evolution of the Indonesian National Research and Innovation Agency, Yulianto Yulianto of the Research Center for Applied Zoology of the Indonesian National Research and Innovation Agency, Kalih Raksasewu of the Yayasan Bentang Edukasi Lestari Bogor Foundation, and Bambang Adriyanto of the Cikepuh Wildlife Reserve, describe a possible sighting of a living Javan Tiger, and the results of an investigation which followed it.

On 18 August 2019, Ripi Yanur Fajar, a local resident and conservationist, reported seeing a Javan Tiger close to the village of Cipendeuy in South Sukabumi Forest, West Java, to Kalih Raksasewu, who visited the site the next day, along with Bambang Adriyanto. Ripi Yanur Fajar described the Tiger as having jumped a fence between a village road and a plantation, and examination of this fence by Raksasewu and Adriyanto led to the discovery of a single hair, which could potentially have come from a Tiger.

The hair recovered by Kalih Raksasewu and Bambang Adriyanto from a fence in Cipendeuy Village, West Java. Indonesian National Research and Innovation Agency.

A genetic analysis was subsequently carried out in which DNA from the hair was compared to DNA from Sumatran Tigers, Bengal Tigers, Amur Tigers, Javan Leopards, and a museum specimen of the Javan Tiger, from Museum Zoologicum Bogoriense, collected in 1930. The hair was found to show a 4.2% difference to the Leopard sample, differences of between 3.7% and 4.1% from the Sumatran, Bengal, and Amur Tigers, but only a 0.3%d difference from the Javan Tiger museum specimen.

Wirdateti et al. stop short of claiming that they have proof that the Javan Tiger still exists on the basis of a single hair, but do believe that the hair comes from a member of the species, and that this merits further investigation into the possibility of a surviving population of these Tigers in West Java.

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Five dead and five missing in West Java following landslide.

Five people, including two children, have been confirmed dead after a landslide hit the village of Cibenda in West Java, Indonesia, slightly before midnight on Sunday 24 March 2024, with another five still unaccounted for. The landslide is reported to have destroyed about 30 houses, and came after weeks of heavy rain in the area, associated with the onset of the Southwest Monsoon. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall.

Rescue workers searching for missing persons following a landslide which hit the village of Cibenda in West Java, Indonesia, on 24 March 2024. Septianjar Muharam/Xinhua,

Landslides are a common problem in Java, particularly during the two Monsoon seasons, with parts of the island receiving 4000 mm of rain per year. This problem has been made worse as expanding populations has led to people farming higher on hillslopes, in an area where soils tend to be volcanic in action and poorly consolidated (i.e. lack much cohesion), making them more prone to landslides when trees are removed.

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 seasons, 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.

Java 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.

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

This year the rains in Indonesia and Southeast Asia have been particularly heavy, due to a prevailing el Niño weather-system over the Pacific Ocean, which is typically linked to more extreme weather patterns in Southeast Asia.

The El Niño is the warm phase of a long-term climatic oscillation affecting the southern Pacific, which can influence the climate around the world. The onset of El Niño conditions is marked by a sharp rise in temperature and pressure over the southern Indian Ocean, which then moves eastward over the southern Pacific. This pulls rainfall with it, leading to higher rainfall over the Pacific and lower rainfall over South Asia. This reduced rainfall during the already hot and dry summer leads to soaring temperatures in southern Asia, followed by a rise in rainfall that often causes flooding in the Americas and sometimes Africa. Worryingly climatic predictions for the next century suggest that global warming could lead to more frequent and severe El Niño conditions, extreme weather conditions a common occurrence.

Movements of air masses and changes in precipitation in an El Niño weather system. Fiona Martin/NOAA.

The development of an el Niño weather-system this year is considered particularly alarming by climate scientists, as the world has had several consecutive years in which average global sea-surface temperatures have equalled or slightly surpassed the hottest previous average temperatures recorded, despite the climate being in a la Niña phase. As sea surface temperatures are typically significantly warmer during an el Niño phase than a la Niña phase, the development of such a phase could push temperatures into areas not previously encountered on Earth since Modern Humans first appeared, potentially triggering or accelerating other climatic problems, such as glacial melting, droughts in tropical forests, and changes in ocean circulation, which might in turn take us further into unfamiliar climatic territory.

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A new population of the Critically Endangered rainforest tree Dipterocarpus littoralis discovered on Social Media.

Social media has become a surprisingly valuable tool for wildlife biologists, with a variety of new species described following posts by curious members of the public seeking to identify unknown organisms. 

In a letter to the journal Oryx published on 8 September 2023, Enggal Primananda and Iyan Robiansyah of the Research Center for Plant Conservation of the Indonesian National Research and Innovation Agency, report the discovery of a new population of the Critically Endangered rainforest tree Dipterocarpus littoralis based upon posts on the social media sites Facebook and Instagram.

Dipterocarpus littoralis had been thought to be restricted to the West Nusakambangan Nature Reserve on the western tip of Nusakambangan Island, which lies of the south coast of Central Java, where the known trees are found in a hilly forest at an altitude of about 100 m above sealevel.

The social media posts show a group of fruits and leaves which Primananda and Robiansyah believe clearly belong to Dipterocarpus littoralis, which were found in Tasikmalaya in West Java, about 70 km to the west of the West Nusakambangan Nature Reserve.

Image of an unknown Diptocarp fruit which Primananda and Robiansyah have identified as Dipterocarpus littoralis. Facebook.

If this identification is correct, then it indicates a significant range extension for Dipterocarpus littoralis, which may require a revision of its conservation status. Primananda and Robiansyah recommend that this new population be investigated as a matter of some urgency, and that specimens from the new location be added to the collection at Bogor Botanic Gardens. 

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