Rare Japanese Rabbit Gets Hitched to Parasitic Plant

Japan’s endangered Amami rabbit has entered into a strange relationship with a parasitic plant called Balanophora yuwanensis. Researchers at Kobe University recently documented the symbiosis between these odd bedfellows.

What makes B. yuwanensis weird is that it does not use photosynthesis to energize itself. Rather, it taps directly into the roots of other plants and trees to power up. In other words, a parasite. The plant produces a fruit-like body that looks like a strawberry, but is in fact a conglomeration of leaves that covers tiny seeds beneath. Scientists have wondered for some time how those seeds are dispersed, since the “fruit” isn’t very palatable to birds, a traditional seed disperser. Enter the rabbit!

The Amami rabbit (Pentalagus furnessi) has its own shortlist of weird characteristics. The five-pound mammal can be found on only two small volcanic islands – Oshima and Tokunoshima in the East China Sea. It is the world’s only wild black-furred rabbit, sometimes called a “living fossil” because its ancestors died out on the Chinese mainland some time ago.

The Kobe scientists spent 52 days on the islands observing the elusive nocturnal creatures. Infrared motion-detection cameras set up near the parasitic plant solved the mystery. Analysis of the rabbit’s fecal pellets confirmed it was feasting on the plant. The Amami turns out to be the perfect delivery system for seed dispersal because it naturally burrows into the ground beneath the very trees the parasite feeds on.

The IUCN has listed the Amami rabbit as endangered. There are about 5000 of them on the islands, where they are prey to mongoose, feral cats, and of course commercial logging. The Kobe research was published this week in the journal Ecology.

Photo credit: Hamada Futoshi / Nippon.com & Yohei Tashiro