BajaNews - 1-3-2007 at 12:03 AM
http://www.guardian.co.uk/international/story/0,,1970682,00....
Jo Tuckman
December 13, 2006
At the centre of Mexico's flag stands an eagle on a prickly pear cactus known here as the nopal, a plant found almost all over the country. But fears
are growing that the nation's eagle could soon lose its perch, its inhabitants a side dish and the world a fiesta of biodiversity.
A moth larva capable of eating its way through huge swaths of cacti from the nopal family at an extraordinary rate has reached Mexican territory - an
island less than six miles from the mainland in the south. The so-called cactus moth is also closing in from the north through the United States, as
well as hovering to the east in much of the Caribbean.
"This is an extremely aggressive plague and it is knocking on our door," said Gustavo González, an official of the Mexican agricultural ministry that
is leading efforts to keep out the moth. "If it gets to areas where there are large populations of nopales it will be very difficult to control."
Cactoblastis cactorum is native to Argentina, Brazil and Paraguay. Unable to fly very high or far, it began its global journey only with the help of
man - taken to Australia in 1925 to help farmers beat a plague of cactus. Prickly pears were taken to Australia by the British who wanted to farm the
cochineal beetle that feeds off the plant as a source of dye for their red coats. Cactoblastis all but cleared the land in four years.
Monuments were built in the moth's honour and Cactoblastis was taken to South Africa and other counties with cacti problems, before being introduced
to Saint Nevis in the Caribbean in 1957.
Once the moth began island hopping from there it became, according to activist Mayra Perez Sandi, only a matter of time before it reached Mexico.
Ms Perez Sandi blames winds and hurricanes, but also cites inadequately controlled commerce in ornamental plants, and seemingly insignificant
accidents such as eggs stuck to the shoes of tourists or migrants, and moths carried in the wheel carriages of planes.
In 1989 larvae turned up in a cactus in a Wal-Mart store in Florida, and the plague has since spread up the peninsula and into Alabama.
The Mexican authorities began a monitoring operation in 2002 in states considered vulnerable to the moth, and last year began partially funding US
control efforts north of the border.
The news that Cactoblastis had reached Mexico came on August 1. It was discovered in a monitoring trap on Isla Mujeres, a ferry ride from Cancún on
the Yucatán peninsula. Further investigation found plants infested with colonies of the black-spotted red larvae eating through the fleshy insides of
their hosts.
This prompted an emergency plan to stop the moth reaching the mainland, which is home to at least 83 of the 120 nopal family species, 56 of them
endemic. Mexicans consume the commoner farmed species in large quantities.
The rare ones are among the 3m hectares of wild nopal that often are among the only plants sustaining semi-arid or desert ecosystems.
The first stage of the plan on Isla Mujeres is to destroy infested cacti. The second, due to start early next year, is to release millions of
mass-bred sterilised males to mate with females.
[Edited on 1-3-2007 by BajaNews]