The island's soft rock, a material called tuff that is primarily composed of densely compacted volcanic ash, is an ideal habitat for the booming population of nanatsuba-kotsubumushi

Through normal weathering, it would usually take thousands of years for the elements to reduce an island the size of Hoboro to debris

But some experts have estimated that, at the current rate, the island may be gone within a century

Hoboro appears to be something of a geological oddity, with no other islands in the immediate area made of the same material.

Although he prefers not to put a time scale on the island's destruction, Okimura added that it's unclear where the burrowing creatures will go when Hoboro does ultimately disappear beneath the waves