Krazy Kiwi wrote:

> >>Asian Mussel - AKA the Asian date mussel. We have this pest in our
> >>Canning River, the Swan Estuary & the Fremantle area. It shares
> >>many features of the Zebra mussel that has caused major damage
> >>in North America.
>
> >The jury is still out on the Zebra mussel.
>
> I find "the jury is still out on the Zebra mussel" comment too simplistic
> considering your country spends over $500 million each year in the Great
> Lakes area cleaning pipes & water systems encrusted with the mussels.
> Included in that cost is dealing with the litter problem (let alone the
> smell) of decaying Zebra Mussels (ZMs) washed up on popular beaches during
> storms.

Of course it's too simplistic, but it's accurate.  The long term affects of
the Zebra Mussels are not yet known.  There seem to be some positive aspects
with the clarity and purity of the water right at the top of the list.  It's
pretty certain that they are filtering and presumably eating what's in the
water.  What is not clear is whether they will continue to eat and grow at
their present rate when the level of "food" is reduced to a stabilized level
and whether there are as yet undiscovered ways to deal with the pipe
clogging issue.  The fact remains that this is one of the very few cases of
a thriving non native species that may eventually prove to have a net
positive effect on the ecology as a whole . . . or not.  That is what the
U.S. expression "the jury is still out" means.  The final results are not
yet known.

Lee