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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Evidence for Indonesian Songbirds being traded on TikTok.

Wild-caught Songbirds are traded across Southeast Asia to be kept as pets or ornaments, released in ceremonies, and, particularly, to be used in singing competitions. This is considered to be a significant threat to many species, to the extent that the International Union for the Conservation of Nature declared an Asian Songbird Extinction Crisis in 2017, with Indonesia considered to be the critical hotspot for this activity. The advent of the internet has provided Songbird dealers with ample new opportunities to reach potential customers, through sites such as the online marketplace OXL. The trade in wildlife (and other illegal goods) via online marketplaces can be fast moving and difficult to address, as dealers will often quickly move to a new website once conservationist or law enforcement agencies become aware of their activities.

In a letter to the journal Oryx published on 21 July 2023, Sicily Fiennes of the Faculty of Biological Sciences at the University of Leeds, and Silvi Dwi Anasari and Novi Hardianto of Kausa Resliensi Indonesia, report that the TikTok platform is being used by traders in in protected and threatened species of Indonesian Birds.

TikTok has about 110 million users in Indonesia. The site joined the Coalition to End Wildlife Trafficking Online in 2021, and subsequently released guidelines which stated that t ‘any content that depicts or promotes the poaching or illegal trade of wildlife is not allowed on our platform and will be removed when identified’. The site claims that 74% of such content is taken down before it is observed by a single viewer, but some well documented breaches of this have occurred, including the promotion of exotic pets in the US, some of which may have been sourced illegally, and the organisation and promotion of Badger persecution in the UK.

Fiennes et al. report an example of at Greater Green Leafbird, Chloropsis sonnerati, being offered for sale on TikTok. Greater Green Leafbirds are currently considered to be Endangered under the terms of terms of the International Union for the Conservation of Nature’s Red List of Threatened Species, and are protected under Indonesian Law. However, the species remains a popular pet across Java. 

An example TikTok post that depicts wild songbird trade in Indonesia. Cak ijo is shorthand for cucak ijo, the trade name for Leafbirds (Chloropsis spp.), PH, paruh hitam (black beak); jamin jantan (guaranteed male, although the photo could show either a juvenile male or an adult female of the Greater Green Leafbird, Chloropsis sonnerati); 450 ecer implies 450 000 Indonesian Rupiah (about UK£24 or US$30); WA is shorthand for WhatsApp. The telephone number and the name of the shop has been obscured.

The online trade in Songbirds presents a range of new challenges for conservationists monitoring the trade in Indonesia. Dealers are clearly incentivised to use such platforms, which give a perception of anonymity, and enable them to reach a wider potential customer base, thereby securing higher sales prices. Fiennes et al. are able to demonstrate that such dealers are able to flout TikTok's guidelines, and recommend that wildlife trade monitoring programs pay more attention to TikTok and other emerging platforms.

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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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Eruption on Anak Krakatoa produces column of ash 3 km high.

Anak Krakatoa, a volcanic island located in the Sunda Strait between Sumatra and Java, underwent a major eruption on Sunday 24 April 2022, producing a column of ash about 3 km high. The volcano had been erupting intermitantly for several weeks, but this event was significantly larger than previous eruptions in this cycle, and 24 hours after the initial eruption the Anak Krakatoa was still erupting intermitently, producing ash columns between 500 m and 3 km high. The Badan Nasional Penanggulangan Bencana has advised that people living close to the volcano wear dust masks when going outside until the volcano subsides.

 

An ash column over Anak Krakatoa (at the right of the image) on 24 April 2024. Dziki Oktomauliyadi/AFP.

Anak Krakatau is a volcanic island located in the Sunda Strait between Sumatra and Java. The volcano (then known simply as Krakatoa) famously exploded in 1883, killing over 36 000 people (possibly over 120 000), largely through a series of tsunamis. This explosion more-or-less completely destroyed the island, but since then a new volcano, Anak Krakatau (meaning the 'son of Krakatoa'), has grown in its place. Anak Krakatau is almost never completely quiet, but goes through periods of greater and lesser activity. An eruption on 22 December 2018 triggered a tsunami which tsunami caused over 430 fatalities, injured 14 000 people, and displaced 33 000 more along the Sunda Strait. The tsunami risk of this area is particularly high as the coast is very popular with both locals and tourists and is home to over 20 million people within a 100 km distance from the volcano.

Anak Krakatau is located to the north of the Sunda Trench, along which the Australian Plate is being subducted beneath the Sunda Plate, on which the island sits. As the Australian Plate is subducted it is partially melted by the friction and the heat of the planet's interior. Some of this melted material then rises through the overlying Sunda Plate, fuelling Krakatau and the volcanoes of Sumatra and Java.

 

The Subduction zone beneath Sumatra. NASA/Earth Observatory.

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