richard@gryphon.COM (Richard Sexton) (10/24/89)
The best way to get rid of mosquitos is not aerial spraying, but - fish.
The mosquito fish - Gambusia affinis, eats 5 times it's weight in
mosquito larva a day. L.A county gives them away (min order is 1000)
to anybody that asks - they even deliver.
Around Rio, in Brazil an evem more voracious set of mosquito
larvae eaters are, however, in trouble. This is the biotope
for Genus Cynolebias, an egg laying tooth carp in Family
Cyorinodontidae. Mother nature has provided these fishes
with a rather unique life cycle. They live and breed
in the space of 8 months, after which they die, Period.
Nothing will keep them alive; indeed they are often used
for senscience experiments. They spawn by laying eggs
deep in the mud. The ponds/rivers/streams dry up, and
the eggs rest, in the mud, over the dry season.
In the spring the rains come, and a new generation hatches
out. The primary diet for this fish in insect larvae of
which mosquito larvae serves the greatest percentage.
Unfortunately, in a short sighted attempt to kill
mozzie larvae, oil is poured int the ponds. The oil
floats on top of the water and prevents the mozzies
from breathing. This kills off the mozzies for
this year, but of course kills everything else in the
pond, and next year the mozzies are back, alas the
fish are not.
Add to this the expansionis, around the booming
cities of Brazil, and you find the habitat of
severel of these species has been destroyed.
It is no longer known where Cynolebias whitei
and C. constanciae exists in the wild. They
are, for all intents and purposes, extinct.
They *may* exist in the wild, but it is not known
where.
Fotunatly these fish exists in the tanks of aquarists
so they are not lost from the face of the earth, but
these fish come and go in cycles - if this fish falls
out of favour among aquarists, or worse, tank stock
through inbreeding becomes genetically retrograde
the species WILL be lost forever.
So, to address the original poster, I personally
feel the idea of using bacteria to kill mosquitos
is little better than using oil. Annual fishes
have certain advantages: 1) they can't take over
an ecosystem because they die off in 8 months
and without the dry period the eggs die - they
absolutely require the dry period for the
third diapause of egg incubation. 2) They
can be used in temporary bodies of water, where,
obviously they can't compete with other fishes,
as there are none. 3) They can adapt to temperatures
from 40 F to 90 F and as such can inhabit most places
on the earth.
I hope I havn't polluted the sci hierarchy with
a hobbyist posting.
Fuck you, Bryce.
--
Surgical tools for mutant women
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