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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Magnitude 5.6 Earthquake in West Java kills at least 162 people

The Baden Meteorologi, Klimatologi, dan Geofisika recorded a Magnitude 5.6 Earthquake at a depth of 10 km in the Cianjur Districs of West Java Province, Indonesia, slightly after 1.20 pm local time (slightly after 6.20 am GMT) on Monday 21 November 2022. The event triggered a series of landslides, as well as causing a large number of building collapses, and is now known to have killed at least 162 people. 

The approximate location of the 21 November 2022 West Java Earthquake. United States Geological Survey.

Many of those who have died are reported to have been children, with at least one school having been severely damaged by the Earthquake, which struck with very little warning. Many homes have also been destroyed and damaged, a hospital in Cianjur District damaged. Much of the area has been left without power, and many roads have been damaged, making communication with more remote areas very difficult. Nurses from the Indonesian Red Cross are reported to be trying to reach several remote villages on motorbikes.

Damage to a school in the Cianjur District of West Java, Indonesia, following an Earthquake on 21 November 2022. ABC News.

The Indo-Australian Plate, which underlies the Indian Ocean to the south of Java, Bali and Lombok, is being subducted beneath the Sunda Plate, a breakaway part of the Eurasian Plate which underlies the islands and neighbouring Sumatra, along the Sunda Trench, passing under the islands, 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 neighbouring islands.

Subduction along the Sunda Trench beneath Java, Bali and Lombok. Earth Observatory of Singapore.

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Double landslide kills at least twelve in West Java.

Twelve people are now known to have died, with another eighteen injured and 27 missing after two landslides hit the village of Cihanjuang in West Java Province, Indonesia, on Saturday 9 January 2020. The first incident happened at about 4.00 pm local time, with a second landslide at about 7.30 pm burying several rescue workers trying to help people buried by the initial incident. The landslides are thought to have been triggered by heavy rain in the area 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.

 

The aftermath of a pair of landslides that hit the village of Cihanjuang in West Java Province, Indonesia, on Saturday 9 January 2020. Antata Photo/Novrian/Reuters.

Landslides are a common problem in Java, particularly during the Northeast Monsoon, which lasts from November to February, with peak rainfall in January and February, and can result in an annual rainfall of around of 4000 mm in parts of Central Java. 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.

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.

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.

Indonesia, and other countries of the western Pacific margin, are experiencing a particularly wet year, due to a prevailing La Niña weather system over the Pacific. The La Niña weather system is the opposite of the El Niño weather system, in which unusually cold surface temperatures spread across the equatorial Pacific from the upwelling zone on the South American coast. This traps warm water from the western Pacific, preventing it from spreading east and warming the central Pacific. This leads to lower evaporation over the (cooler) east Pacific, leading to low rainfall on the west coast of South America, and higher evaporation over the (warmer) west Pacific, leading to higher rainfall over East and Southeast Asia and northern Australia.

The effects of a La Niña weather system in December-February. NOAA.

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Landslide in West Java kills one and injures two.

One person has been killed and another two injured in a landslide that hit the village of Sindangkerta in West Java, on Friday 20 November 2020. The landslip covered a road damaging a car and motorcycle, and occurred during a severe rainstorm. 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.

 

The scene of a landeslide in West Java that killed one person and injured two others on Friday 20 November 2020. Agung Rajasa/Antara News.

Landslides are a common problem in Java, particularly during the Northeast Monsoon, which lasts from November to February, with peak rainfall in January and February, and can result in an annual rainfall of around of 4000 mm in parts of Central Java. 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.

The approximate location of the 20 November 2020 landslide. Google Maps.

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.

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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