This week, the National Zoo once again welcomed several new habitants. Four Japanese giant salamanders have arrived as a gift from the City of Hiroshima Asa Zoological Park, and join the lone Japanese giant salamander who already lives on the Asia Trail.
Japanese giant salamanders, or oosanshouo (pronounced OOH-sahn-show-uuh-ooh), can grow up to 5 feet long and weigh up to 55 pounds. The natural home of the reptiles is the cold mountain streams and rivers of northern Kyushu and western Honshu in Japan. Their brown and black skin helps them to blend in with the mud, stones and plants of the streambeds, and their broad, flattened bodies are streamlined for swimming at the bottom of the fast-flowing water.
Although the Japanese giant salamander has no natural predators, they are hunted by local populations for food and much of their habitat is lost to deforestation. As such, the species is listed as 'near threatened' by the International Union for Conservation of Nature and are protected from international trade by the Convention of International Trade of Endangered Species.
The Japanese giant salamander has emerged as the flagship species for salamander conservation as scientists and conservationists struggle to combat a global amphibian crisis. According to the Zoo, "nearly one-third of the world’s more than 6,000 amphibian species are in danger of extinction, resulting in the worst extinction event since the time of the dinosaurs." The arrival of the reptiles has prompted the opening of a breeding center, where the new additions will live.
Scientists at the Zoo will not only study how they reproduce, they will also learn about the chytridiomycosis ("chrytrid") fungus that is lethal to some amphibian species, but not to the Japanese giant salamander. Studying the fungus will mean that these salamanders may contribute to the survival of their own species and other amphibians around the globe.
This morning, an opening ceremony at the National Zoo introduced the breeding facility to the media and Ichiro Fujisaki, the Japanese ambassador to the United States. Members of the public had the opportunity to see the young Japanese giant salamanders up close, while the were fed by staff at the Zoo, which, according to Ed Bronikowski, senior curator at the Zoo, is a remarkable spectacle.
This species has not been bred outside of Japan in more than 100 years, but the Zoo is now establishing a long-term breeding program in the United States. In the wild, salamanders begin to reproduce in late August, when females lay between 400 and 500 eggs. Males often compete viciously to fertilize the eggs, with many dying due to injuries from fights. Once the eggs are fertilized, they are guarded aggressively by the male salamanders, until they hatch in early spring. And as for the four new 11-year old salamanders at the Zoo. "They are only just coming into sexual maturity. It may be too early for them this year," explains Ed Bronikowski. But as for next year? "We'll see," he says.