This week–

IN THE pantheon of evolutionary

icons they have prime status – for

biologists they are the closest

thing to Mecca. Now the

Galapagos islands are facing a

two-pronged attack.

On one side are the rats, goats

and other alien species that have

made the islands their home, to

the detriment of local flora and

fauna and on the other, the

hordes of eco-tourists descending

on the equatorial paradise.

Last year around 126,000

people visited the Galapagos, and

cruise ship companies have

recently added the islands to their

destinations. Felipe Cruz of the

Charles Darwin Foundation,

dedicated to conserving the

islands, believes the Galapagos

should not be used in this way.

“We don’t want cruise ships in

the Galapagos, we don’t think it’s

sustainable,” he says. The ships

leave local people and the

environment to deal with their

laundry water and sewage waste.

Second, the larger numbers of

tourists visiting the same areas

will disturb the wildlife. Third, the

chances of bringing alien species

or disease is greatly increased.

Cruise ships, however, are

coming. The Ecuadorean

government allows twelve 500-

passenger cruise ships to visit the

Galapagos a year . So far the only

one has been the 698-berth

MV Discovery, operated by

Discovery World Cruises of Fort

Lauderdale, Florida, which visited

in May. Classic International

Cruises, based in Lisbon, Portugal,

has the Athena, which is

scheduled to visit in 2008. Cruz

says the ships bring their own

food with them and don’t deal

with local people, so the tourist

money doesn’t filter into

sustainable tourism.

Pirates used the islands as

hideouts until the 19th century,

introducing many non-natives

such as rats, pigs and goats.

Leonor Stjepic of the Galapagos

Conservation Trust in London

says the potential ecological

impact of mass tourism poses a

similar threat. “It is very

difficult to perform adequate

quarantine checks on a large ship

with lots of people and luggage,”

she says. “West Nile virus has

already been detected in

Colombia. Imagine the

devastation if that – or avian flu –

came to the Galapagos.”

When asked about the

ecological risk to the islands,

Classic International Cruises

told New Scientist they will

comply with the rules set by the

Ecuadorean government and the

Galapagos National Park

Management as far as protecting

the islands is concerned.

Stjepic insists that cruise ships

are not a good thing for the

islands. “It goes beyond

environmental impact

assessment. Even now we get

invasive species, such as thrips,

and blackberry, which has

devastated the daisy trees in the

highlands of Santa Cruz.”

Managing the Galapagos is

difficult, but there are successes.

Most notably, Project Isabela,

which eradicated thousands of

goats that had devastated many of

the islands in the archipelago.

Even large islands like Santiago

and Isabela, each home to almost

100,000 of these alien invaders,

are now goat-free. “The success of

this project has acted like a

catalyst, giving us confidence to

take on other huge challenges in

Galapagos,” says Cruz.

Later this year the island of

Pinta is to be the setting for one of

the boldest. One hundred giant

tortoises from nearby Española

will be released onto Pinta’s

volcanic slopes. There is only one

surviving Pinta tortoise,

Lonesome George, and he was

moved to the Charles Darwin

Research Station on the island of

Santa Cruz in 1972. His closest

living relative – the Española

Trouble in Darwin’s paradiseCan the Galapagos islands survive the onslaught of mass tourism and the invasion of non-native species?

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This week– International news and exclusives

8 | NewScientist | 14 October 2006 www.newscientist.com

HENRY NICHOLLS

THE GALAPAGOS ISLANDSRealm of the giant tortoises

0°

1°

91° 90°

PACIFIC OCEAN

Isla Isabela

Isla Fernandina

Isla Santa Maria

Isla Española

Isla San Cristóbal

Isla Pinta

Isla Marchena

Isla San Salvador

Isla Santa Cruz

tortoise – will act as a stand-in for

him and his long-dead ancestors.

“This is the first time that

conservationists in the Galapagos

have attempted to replace one

species with another,” says Cruz.

The tortoises should fill a hole

in Pinta’s ecological make-up. “In

the absence of a dominant

herbivore, the structure of the

island’s vegetation is changing,”

says Ole Hamann, a botanist at

the University of Copenhagen in

Denmark who has worked on

Pinta since the 1970s. “Tortoises

will open up the vegetation,

making room for light-loving

herbs and grasses.”

Next for eradication are the

non-native rats . In 2003,

conservationists announced that

around 200,000 Norwegian rats

had been removed from Campbell

A SMALL nuclear explosion, barely a

fifteenth the size of the bomb that

levelled Hiroshima, has shaken the

world’s uneasy nuclear balance. On

Monday North Korea announced it

had successfully triggered a nuclear

device deep in a coal mine in the

north of the country. A second test

was considered possible as New Scientist went to press.

The thought that maverick North

Korean leader Kim Jong-il now has

nuclear weapons to use or sell may

herald the collapse of the already

shaky global non-proliferation

regime by prompting neighbouring

South Korea and Japan to join the

nuclear club. Yet ironically North

Korea’s act proves how well the 1996

Comprehensive Test Ban Treaty is

working. “That test was really well

detected,” says Paul Richards of

Columbia University in New York, who

helped develop the CTCB’s seismic

monitoring network.

The network was not expected to

reliably pick up explosions of less

that 1 kiloton. Yet the waveform of

the signal showed it couldn’t be an

earthquake, says Richards. He and

other experts contacted by New Scientist agree the device was small.

It may even have been only half a

kiloton – the same explosive power

as the terrorist bomb in Oklahoma

City in 1995. The Hiroshima bomb was

15 kilotons.

The seismic network even shows

Kim was not trying to bluff the world

with a big conventional explosion. US

experiments in the 1990s showed

how difficult it is to mimic a nuclear

blast with chemical explosives, plus

“a satellite should have seen trains

delivering the hundreds of tonnes of

explosive”, concludes Richards.

A gust of released radionuclides

at monitoring stations could clinch

the matter, though their absence

might only mean the test was small

and deep enough to be contained.

Site inspections, of the kind called for

by the CTBT, would verify the nature

of the explosion but the treaty has

IN THIS SECTION

● Victoria, this is opportunity, page 10

● Drugs reverse heart-attack damage in rats, page 12

● Cosmic rays know their limits, page 14

–Returning home–

yet to be ratified by a handful of

nuclear countries – including the US,

which has said it will not do so.

Less clear is whether the blast was

the product of a small bomb or a

larger one that fizzled out. If large it

would cast doubt on North Korea’s

real nuclear expertise. Small bombs

are harder to make, as the chain

reaction has to be very precisely

induced when the amount of fissile

material is limited. To overcome this

technical hurdle, says Friedrich

Steinhäuseler of the University of

Salzburg, Austria, the North Koreans

would need the right tools, such as

laser-guided lathes which are

capable of shaping deflectors that

can accurately concentrate neutrons.

There is no reason to assume this is

not the case, says Steinhäuseler, or

that the size of the blast was not

deliberate. “When you have only a

little material you save it. The political

signal is independent of the yield.”

The political signal has been

heard loud and clear. “This reported

nuclear test threatens the nuclear

non-proliferation regime,” warns

Mohamed ElBaradei, head of the

International Atomic Energy Agency.

“We will be entering a new,

dangerous nuclear age,” Japanese

prime minister Shinzo Abe agreed

on Monday.

That, of course, will depend on

what North Korea can do with its

bomb. Experts agree that it is probably

too heavy to fit onto any North Korean

missile. But a small device could be

detonated remotely in a shipping

container, say, wreaking havoc in a

port, and in the world order. One

measure now before the UN Security

Council would impose mandatory

inspections on all ships leaving North

Korea. Debora MacKenzie ●

“That North Korea now has

nuclear weapons to use or sell

may herald the collapse of global

nuclear non-proliferation”

Nuke test sends shock waves round world

www.newscientist.com 14 October 2006 | NewScientist | 9

Island, some 700 kilometres

south of New Zealand. It was the

most successful rat eradication

scheme to date and the technique

used, an aerial drop of poison

specific to rats, is due to come to

the Galapagos soon.

With cruise liners and mass

tourism, however, enforcing

adequate quarantine measures

will be very difficult, says Stjepic.

At the end of this month,

there will be workshops to look

at ways of capping the number

of visitors to the islands . One

obvious way is to put the price up,

from the $100 entry fee currently

charged, to $500.

“We believe that the only way

to ensure sustainable tourism and

consequently a sustainable

society in Galapagos will be

through alliances among

government, tourism, private

sector, conservation groups and

the local community,” concludes

Graham Walters of the Charles

Darwin Foundation. Additional

reporting by Rowan Hooper ●

“One obvious way of capping

visitor numbers is to put the

price up, from the $100 entry fee

currently charged, to $500”