Episode 488: The Java Tiger Mystery

Further reading: Is the Javan tiger Panthera tigris sondaica extant? DNA analysis of a recent hair sample The Sunda tiger [photo by Alfonsopazphoto – Own workAnimaisFotos, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=16029853]: Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. We’re going to learn about a mystery tiger this month, but first we have to learn about the place where it’s supposed to live. Java is a large island that was formed by volcanic activity millions of years ago, and it’s been home to humans and our ancestors for over a million years. Its soil is rich and the climate is tropical, but the island’s ecosystems include tall mountains, savannas, rainforests, and mangrove forests. Naturally, lots and lots of animals live on Java that are found nowhere else in the world. Unfortunately, a whole lot of people live on Java too, which means that many animals and their habitats are threatened by habitat loss and pollution. Many animals have gone extinct in the last few hundred years. That includes the Java tiger. The Java tiger was small compared to tigers in other areas, although even a small tiger is a big animal. A big male tiger can grow about ten feet long, or 3 meters, and the Java tiger could grow about 8 feet long, or almost two and a half meters. The Java tiger was lightly built, though, and rarely weighed much more than 300 pounds, or about 140 kilograms. Despite its relatively small size, it was extremely strong and had paws as big as the much larger Bengal tiger. It also had lots of thin stripes. Originally scientists thought the Java tiger was a separate subspecies of tiger, but in 2017 it was reclassified as a population of Sunda tigers that have only been isolated from other populations for around 12,000 years. That doesn’t mean it wasn’t important, though. It showed differences from other Sunda tigers that weren’t yet significant enough to warrant it being a separate subspecies, but which definitely indicated it was on its way to evolving into a separate subspecies. Unfortunately, the Java tiger’s habitat was largely destroyed to make way for farming and logging, and as a result its usual prey animals became rare or went extinct. People would also poison or shoot any tiger they could. It only survived in a few small nature preserves, but the last tiger footprints were spotted in 1989 and since then, no tigers have been officially seen on Java. A 1999 expedition that set up camera traps in hopes of spotting a few tigers mostly got photos of poachers hunting in what was supposed to be a protected area. The Java tiger was declared extinct. Rumors persisted that tigers still lived on Java, though. Sometimes I think people claim to see recently extinct animals as a way to feel less guilty about humans having driven an animal to extinction. But in 2019 someone saw a tiger outside a village in western Java and reported the sighting to some local foresters. The foresters investigated and discovered footprints, claw marks, and a single hair on a fence. The foresters collected the hair carefully and gave it to a team of geologists who were working in the area. The geologists sent it to the West Java Nature Conservation Authority, which sent it for genetic analysis. They also sent some tiger hairs from other types of tigers to compare it to, including hairs from a museum specimen of a tiger killed on Java in 1930. The hair discovered in 2019 was definitely from a tiger, and its genetic signature most closely matched the genetic signature of the 1930 Java tiger specimen. This doesn’t 100% mean the Java tiger isn’t extinct, but it does mean that there’s hope that it’s still around. Java is part of Indonesia these days, and a few days ago as this episode goes live, the Indonesian government announced a plan to search for signs of the tiger, with an expedition getting underway soon to place camera traps. Conservationists are hoping that the tiger is discovered, which will allow it to be protected. The Sunda tiger is critically endangered, only surviving in the wild on the island of Sumatra, with possibly fewer than 400 of them left alive. Another population of Sunda tigers, the Bali tiger, was declared extinct in the 1940s. A few hundred captive tigers living in zoos around the world show congenital health issues as a result of inbreeding. If the Java tiger is still alive, it could mean the difference between extinction and survival of the entire Sunda tiger subspecies. Fingers crossed that the camera traps reveal a healthy, safe population of tigers on Java! Thanks for your support, and thanks for listening!