On 20 Apr 2001, at 3:38, Krazy Kiwi wrote:


>
> >Recent reports suggest that this filter feeder is actually cleaning
> >up badly poluted waters. While it's rare, this may be a case where
> >a non native species has a positive effect.
>
> Yes, ZMs can filter 1-2 litres of water per day with the benefit of better
> viz - diver heaven :-)  But currently I see more negatives than positives
> regarding this pest :-(

It was thought that the ZMs were cold water critters too and that we,
here in the warm and sunny south would not have to worry about
them. They have been found now in the Tennessee River chain as
far  south as Knoxville in significant numbers and a few have already
made their way further south towards Chattanooga. As a diver this
could be good news for me since I love diving the river. As a
consumer of the power that is produced by the many dams  along
this river I am worried about what it's going to do to my power bills.


>
> In San Diego the eelgrass beds may or may not benefit from ZMs.
> Studies have shown if it is a HEALTHY & DENSE bed of eelgrass the ZM
> starves to death.  Unfortunately, if the eelgrass beds are DEGRADED they
> are overtaken & smothered by the ZMs.  The later is not good news for many
> of the creatures that depend on that eelgrass for food & habitat (lobsters,
> green turtle, shrimp, scallops, salmon, brant geese, etc).

Our rivers and lakes have been infested for many years by Milfoil, a
grass that was not native to us. It covers huge areas of the rivers
and lakes that the ZM is slowly making it's way to. Should they get
this far and cause a lot or all of this grass to die, the fisherman and
skiers and others would love it for the first few years. As the fish
populations start to decline because of it, this love won't last.


> I suppose if it gets to plague proportions we could export it to China,
> they eat it. I doubt it will ever appear on the seafood menu in this
> country due to its small size. A couple of uses I hear it is good for is
> fish bait, and as feed for shrimp & crab farms in Japan.

How about fertilizer?


> Viv