disinfectant, and their clothes are vacuumed. But scientists and the staff
manning tourist expeditions are laxer, as
revealed in the new seed counts.
“Everyone has a favorite jacket, and
there’s a tendency for staff to wear the
same gear a lot and not clean it as much,”
Some areas flagged in the new study
have already been infiltrated. An upcoming paper in Conservation Biology
reports that an aggressive species of
alien grass has appeared outside three
scientific research stations on the
Poa annua made its Antarctic
debut in the 1980s, after having been
brought — unintentionally — to a
Polish outpost on King George Island.
The weedy plant escaped and grew in
patches on the island, which is close
enough to the mainland to be considered part of Antarctica. Wind then
carried seeds 1. 5 kilometers away from
the station, where the grass sprouted on
debris left behind by a retreating glacier.
“It’s starting to get to the point
where this grass is beyond control in
Antarctica,” says Kevin Hughes, an environmental scientist with the British
International law forbids the introduction of new species to Antarctica.
But the rules are fuzzier about what
steps should be taken to deal with species that have become established in the
wild. Nothing has been done to get rid of
the grass intruder, Hughes says.
What impact the plant will have on
Tens of thousands of foreign seeds may make their way to Antarctica each summer,
a recent analysis finds. Most of the potentially troublesome seeds collected as
part of the analysis (some shown) were carried by scientists and expedition staff.
native life isn’t yet known. But the same
species has already overrun islands
near — but not part of — Antarctica. On
the island of South Georgia, the grass has
replaced indigenous vegetation in some
spots and stunts the growth of beetles
that have trouble digesting the grass.
This fly, Trichocera maculipennis, has
What’s bugging Antarctica
been seen in a new home—on King
George Island, off Antarctica’s coast.
Plants aren’t the only potential invaders.
Research stations have become beachheads for microbes, fungi, insects and
worms. In 2005, construction vehicles
brought by ship to a British outpost came
with attached soil teeming with life. Produce imported to feed visitors can also
carry infested dirt.
“About 12 percent of all fresh food
items traveling to Antarctica are contaminated,” says Dana Bergstrom, a polar
ecologist with the Australian Antarctic
Division in Kingston. Bergstrom and colleagues reported that statistic last year in
Biological Conservation after examining
more than 11,250 fruits and vegetables
shipped to nine research stations.
Contaminated soil is supposed to be
destroyed when discovered, but a few
foreign agents have slipped through the
Flies made themselves at home in the
sewage system of an Australian research
station and in a British station’s liquor
store. Initial efforts to eradicate the
insects failed at the Australian base.
Their eggs endured, allowing the pests
to spawn year after year. When reporting
on the insects in 2005 in Polar Biology,
Hughes and colleagues suggested that
the bugs couldn’t survive the bitter
cold outside, meaning they probably
wouldn’t spread into the wild.
s Learn about the wildlife inhabiting
Antarctica at the British Antarctic
Survey’s website: www.antarctica.