The endangered and elusive Amami rabbit (Pentalagus furnessi) has been revealed as a crucial player in seed dispersal for the non-photosynthetic plant Balanophora yuwanensis, shedding new light on the previously unknown ecological role of the world’s only dark-furred wild rabbit.

Despite being a flagship species of the Ryukyu Archipelago, the Amami rabbit remains poorly understood due to its rare and nocturnal nature and the dense forests that it inhabits on two subtropical islands.

The mystery of how the tiny seeds of the non-photosynthetic Balanophora plant were dispersed has puzzled researchers, but a recent discovery by Professor SUETSUGU Kenji and graduate student Mr. HASHIWAKI Hiromu of Kobe University’s Graduate School of Science has shed light on the subject.

Observing feeding marks on Balanophora yuwanensis plants on Amami-Oshima Island in Japan, the researchers discovered that the endangered Amami rabbit plays a key role in seed dispersal for this rare plant species.

On the island of Amami-Oshima, Suetsugu and Hashiwaki carried out research in the understory of thick woods in order to test the validity of this idea.

Using cameras that were set off by infrared light, they saw that the Amami rabbit was the main animal that ate B. yuwanensis fruit (Figure 2).

Also, all of the Amami rabbit poop samples taken in the field had at least a few B. yuwanensis seeds that were still alive (Figure 3). This is new evidence that the elusive rabbit species helps spread seeds.

Since Balanophora yuwanensis is an obligatory parasite, its seeds can only develop if they are implanted close to the roots of a suitable host plant. The Amami rabbit’s habit of creating burrows for both living in and eliminating waste may contribute to this.

It’s interesting to note that the B. yuwanensis plant produces dry fruits, although seed dispersers are normally motivated by juicy fruits, and yet the Amami rabbit serves as a seed dispersal agent for the plant.

As the video shows, the rare species of rabbit ate both dry fruits and plant parts from B. yuwanensis. This is important because, because rabbits eat mostly leaves and not fruits, their possible role as seed-spreaders has been mostly overlooked.

However, this research shows that the Amami rabbit, encouraged by the plant’s vegetative tissue, acts as a significant seed disperser for B. yuwanensis.

The research sheds light on the previously unknown role of the endangered Amami rabbit as a seed dispersal agent for the non-photosynthetic plant Balanophora yuwanensis, and suggests that the species may have other important ecological functions yet to be uncovered.

The results were published in Ecology today.

Image Credit: Yohei Tashiro