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Slates
12-07-2002, 05:07 AM
G'day all.
The link below takes us to a study conducted by CSIRO about the possibility of some blooms of blue-green algae being blamed on an over-population of top predators in some impoundments.

As a fisherbloke from Vic, I reckon there are a lot of fish in some QLD dams or is it just the return rate (per angler? (ie: more than Vic impoundments)
I'm not dead sure.
I'd like to compare the fish stocking per square kilometer (or whatever) in QLD dams to Vic dams.

Cheers, Slates

http://www.csiro.au/index.asp?type=mediaRelease&id=Prvlad

DavidR
14-07-2002, 06:41 AM
Short media releases are often noticably absent of the information needed to get a good idea of the outcomes of a study dealing with an issue as complex as this one. Often a lot of the important details are not provided so you are left asking more questions than are answers.
Any scientific study shouldn't be judged solely on a media release without any details. As with a lot of scientific studies, there is a miltidude of other factors playing a part in the observed outcomes and the results may not always be as cut and dry as it may first seem. These types of studies have been done a lot overseas and the effect on algae has not always been consistent. This study is one of the first of it's type on a large scale undertaken in Australia. Given we know relatively little about the impacts of stocking top predators in our dams, this type of research is essential as long as the outcomes are put in context with the complexity of the system.
On your point regarding stocking rates between Qld and Vic dams, i think there are many fundamental differences between temperate and sub-tropical lakes that probably make this comparison difficult to draw any conclusion on. For a start southern dams have totally different blue green algae species as do Qld dams. This fact alone means the algae responses to stocked fish could be vastly different.
Anyhow it is good to see that research is beginning on effects of stocking fish in dams as this can only be a good thing overall.
David