RE: [RML] Disease in wild-caught fish

Matthew Stanton (matthews at sf.nsw.gov.au)
Tue, 9 Mar 1999 09:37:59 +1100

Yes! Acid sulphate soils are pretty powerful stuff.
I remember when I was at Uni some years ago, having a field trip to a site
where acid sulfate soils were being disturbed on the Richmond River. The
disturbance was from a Teatree growing project where they were plowing the
mud and running drains into the river. At the point where one drain entered
the river the pH was measured at 3.1 and in the drain itself our probe went
into freakout mode and wouldn't give a reading for some reason. In the river
there were masses of dead fish floating with red sores on some of them
although others appeared completely unmarked. Most of the fish were mullet.
There were a few herring and small fish that were mush and unidentifiable.
There were also strandlines of water insects.
The scene was topped off by the water colours. The main river channel was a
normal greenish colour. The drain water was blue, a milky blue where there
was flow and a clear blue in the eddies.
I guess it is unlikely that this is what injured Jennifer's fish but it is
always a possibility on coastal plains.

Matthew
Ecology Research, State Forests NSW - Ph0298720182 Fx0298716941
> -----Original Message-----
> From: Bruce Hansen [SMTP:bhansen at ozemail.com.au]
> Sent: Monday, March 08, 1999 11:29 PM
> To: rainbowfish at pcug.org.au
> Subject: Re: [RML] Disease in wild-caught fish
>
> Mostly I have found Rhads in coolish flowing soft acid streams -
> occasionally in still waters and rarely in poor condition. I must admit
> that they are generally in backwaters rather than in the flow proper so
> perhaps a sudden increase in turbulence could be damaging but I agree that
> chemical stress from a sudden large change in pH or pollutant could be the
> culprit. I have found Rhads in water as low as pH 5 ( or perhaps even
> lower
> but the test kits are generally not too good below that) so the water
> from
> acid soils must be pretty powerful stuff
>
> I feel that the"ratty fins" and secondary fungal infections may have been
> from turbulence but parasites seem more common when fish are temporarily
> confined in smaller bodies of still water between rainy seasons and are
> often the intermediate stages of trematode parasites of water birds. So
> this
> is an interesting collection of problems from the 2 opposite environmental
> situations - first too little flow and then too much flow
>
>
> Regards,
> Bruce.
>
> Bruce Hansen, A.N.G.F.A., Advancing Australian Aquatics.
>
> Bruce Hansen, ANGFA, caring for our aquatic ecosystems.
>
> Please visit us at http://www.ozemail.com.au/~fisher/angfa.htm
>
>
> -----Original Message-----
> From: Jennifer Palmer <aquamail at mypostbox.com>
> To: rainbowfish at pcug.org.au <rainbowfish at pcug.org.au>
> Date: Wednesday, 3 March 1999 10:19
> Subject: Re: [RML] Disease in wild-caught fish
>
>