Indian blue worms set up in competition to 'tigers' in compost
[News release from New Zealand Institute of Crop and Food Research]
Wellington, Oct 24
A "new" exotic earthworm species, the "indian blue" has been quietly
spreading across the nation [New Zealand] in worm farms, soil biologists
The indian blue, scientifically known as Perionyx excavatus, is now thought
to be widespread, and a second exotic species, Dendrobaena veneta, has
been identified from one site.
Crop and Food Research earthworm specialist, Trish Fraser, said it was
unclear how or when the species arrived in the country.
"Most of the earthworms that we find day to day in New Zealand are
introduced from Europe but the indian blue is actually from Asia," she said in
"These 'new' species may have been here for a while though, if they have
been, I'd be surprised they were not found before," Dr Fraser said.
It was possible other earthworm species were present without having been
recorded, she said.
"At the latest count we had 197 species... but the last time an extensive
survey was conducted was in 1959," she said.
The indian blue prefers to live in high amounts of organic matter and is
probably the second most popular species, after Eisenia fetida (the tiger
worm), used worldwide in worm farms. It was possible the indian blue would
compete with tiger worms for food in worm farms.
"The Indian blue is also known as 'the traveller' because if there's an
unfavourable shift in environmental conditions it will rapidly move to find a
new home," she said. Because it was commonly found in warmer climates it
was more likely to survive in the warmer areas of New Zealand.
However, the other species found, Dendrobaena, came from Europe so was
likely to survive right across the country. It also preferred an environment
high in organic matter, such as compost heaps.
Both earthworm samples were supplied by an Auckland worm farmer with
Dr Fraser and colleague, Jacqueline Piercy, making the initial identifications,
later confirmed by an Australian earthworm taxonomist.
Geoff Read <g.read at niwa.co.nz>
-- ANNELIDA LIST
Discuss = <annelida at net.bio.net> = talk to all members
Server = <biosci-server at net.bio.net> = un/subscribes
Archives = http://www.bio.net/hypermail/annelida/
Resources = http://www.annelida.net/