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Subject: TWL: An Environmental Whacko Responds
From: Alex Hirsekorn (alexh@XXX.XXX)
Date: Mon Dec 02 2002 - 17:39:38 EST
----- Original Message -----
From: "Kurt Reno" <kreno@XXX.XXX>
>
> Here in Ohio the farmers load up ponds with Copper Sulfphate to the point
> where the ponds are totally blue. The fish do fine, the algae dies and the
> people eat the fish. Copper Sulphate is much better at suppressing growth
> than Copper Oxide because of its total solubility. Nobody is screaming here
> in Ohio. I suspect that the Enviro-Whacko's have no real evidence of damage
> caused by antifouling paints but just suppose it happens.
>
Hi Kurt,
I think that if you were to research this topic in a bit more depth you would find that
comparisons between a small (<10acre) fishpond and the ocean are not very useful.
Copper compounds are not very toxic to vertebrates such as fish and people but are
extremely toxic to invertebrates like arthropods and mollusks. In the fish ponds you
describe, I suspect that even without the copper fish would be the main component of the
total animal biomass and that the farmer would need to do some supplemental feeding. With
the copper, the fish are probably just about the only thing left alive and the farmer
needs to feed more heavily because the arthropods (insects) and mollusks (snails) that the
fish would normally be eating are gone.
In saltwater, on the other hand, invertebrates make up the largest part of the total
animal biomass. In keeping with the example above I'm just going to discuss two groups,
arthropods (crustaceans) and mollusks. Crustaceans include the barnacles that we're trying
to discourage with copper bottom paint but, as I'm sure you know the group also includes
crabs, lobsters, and shrimp which all look darn good on my dinner plate. Mollusks include
the mussels that foul boat bottoms and shipworms (actually a type of clam) that can be
very destructive to any submerged wood (like dock pilings and older Grand Banks)but also
include the mussels I like to steam, the clams I like in chowder, as well as oysters and
scallops which I don't much care for but maybe you do.
The examples above are all things that people like to eat but you might want to think
about some of the things down there that we don't eat like the hundreds or thousands of
different species of worms that keep the bottom stirred up and not smelling like an
overused outhouse; the thousands of filter feeders from virtually all of the invert
families that keep the water from becoming a solid mass of diatoms; the copepods (A very
tiny crustacean) that forms the base of the food web and without which we wouldn't have
seafood; or all the things that are just cool to look at like anemones, nudibranchs, and
sea stars.
To say that there is no evidence of damage is simply incorrect. All one has to do is to
look at what lives in the boat basin compared to what lives in any other sheltered
environment in the same area. You'll find that the marina supports fewer animals and FAR
less diversity than does a comparable wild area.
As an aside, the floating piers of a marina do support their own unique ecosystem because
they provide a shallow water environment that is never exposed by the tide but,
nonetheless, the benthic (bottom) environment is "where the action is" and that
environment is more sparsely and poorly populated in areas where there is copper present.
Used properly, copper bottom paint isn't all that destructive to the environment but
that's a far different statement than saying it has no effect at all. I use copper paint
on my boat but I'm very happy that there are people out there that are working toward an
anti-fouling solution that is less destructive.
The fact is; we environmental whackos have lots of evidence. What we seem to lack are the
marketing skills and/or resources to convince the folks on the other side of the fence.
Greenly yours
Alex Hirsekorn
Docent/Naturalist
Feiro Marine Life Center
Port Angeles, WA
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