By Kyoko Hasegawa
A brand new island emerging off the coast of
Japan offers scientists a rare opportunity to study how life begins to colonize barren land -- helped by rotting bird poo and hatchling vomit.
Researchers say bird waste will be the secret
ingredient to kickstart Mother Nature's grand experiment on what is a
still active volcano that only poked its head above the waves in
November 2013.
That speck of land, some 1,000 kilometers (620
miles) south of Tokyo, has grown to engulf its once larger neighbor,
Nishinoshima, a part of Japan's Ogasawara island chain known for the
wealth and variety of its ecosystem.
The new Nishinoshima, a
respectable 2.46 square kilometers (0.95 square miles), the Japan Coast
Guard said in February -- roughly the size of 345 football pitches -- is
currently almost all bare rock, formed from cooling lava.
But
scientists say it will one day be humming with plant -- and possibly
animal -- life, as nature moves in to what is being called a "natural
laboratory" on one of the latest bits of real estate in the Pacific
Ocean.
"We biologists are very much focusing on the new island
because we'll be able to observe the starting point of evolutionary
processes," said Naoki Kachi, professor and leader of Tokyo Metropolitan
University's Ogasawara Research Committee.
After the volcanic
activity calms down, "what will probably happen first will be the
arrival of plants brought by ocean currents and attached to birds'
feet," he said.
Those seabirds, who could use the remote rock as a temporary resting place, could eventually set up home there.
Their
excreta -- along with their dropped feathers, regurgitated bits of food
and rotting corpses -- will eventually form a nutrient-rich soil that
offers fertile ground for seeds carried by the wind, or brought in the
digestive systems of overflying birds.
"I am most interested in
the effects of birds on the plants' ecosystem -- how their bodily
wastes-turned-organic fertilizers enrich the vegetation and how their
activities disturb it," Kachi said.
The old Nishinoshima,
measuring just 0.22 square kilometers, was home to bird colonies until
the eruptions scared the creatures away.
A small number have
clung on to the only patch of the old island that is still visible,
making their nests among ash-covered plants.
- Pristine -
Japan, which sits at the junction of several tectonic plates, is home to more than 100 active volcanoes.
Scientists have no idea when Nishinoshima will stop spewing lava, but its expansion is being offset by erosion around the edges.
The
island is expected to follow a route laid out by Surtsey, an island
that emerged from the sea in 1963, around 30 kilometers from the coast
of Iceland.
The UN Educational, Scientific and Cultural
Organization (UNESCO) World Heritage spot is known globally as an
outstanding example of a pristine natural laboratory where researchers
have been able to trace the evolution of a habitat.
"Since
they began studying the island in 1964, scientists have observed the
arrival of seeds carried by ocean currents, the appearance of molds,
bacteria and fungi, followed in 1965 by the first vascular plant,"
UNESCO says on its website.
"By
2004, (vascular plants) numbered 60, together with 75 bryophytes, 71
lichens and 24 fungi. Eighty-nine species of birds have been recorded on
Surtsey, 57 of which breed elsewhere in Iceland. The 141 hectare island
is also home to 335 species of invertebrates."
Not bad for somewhere that has only existed for half a century.
Nishinoshima
might not be quite as quick as Surtsey to establish itself as a teeming
wildlife haven -- it is a long way from mainland Japan and not too
close to its neighbors in the Ogasawara island chain, which limits the
number of species of birds and seeds that will make it that far.
Nonetheless,
it is an exciting blank canvas, said Kachi, and needs to be treated
with respect -- which means keeping out foreign invaders that would not
naturally drift or fly in.
"I'd
like to call on anyone who lands on the island to pay special attention
to keeping it the way it is -- not to take external species there," he
warned.
He said when he
conducted a field study on another island in the chain in 2007, his team
prepared a fumigated clean room where they packed all research
equipment, after making sure everything they had was either brand new or
scrupulously clean.
While
Nishinoshima is currently only being monitored from the air, the first
field researchers will need to take similar precautions.
"Biologists
know the business, but probably the first batch of scientists who will
land on the island will be geologists and vulcanologists -- who may not
be familiar with the problems," he said.
"I'd be pleased to offer advice on this to scientists in other fields."
