Glad you guys are enjoying my posts.
These pics are of the Goulburn River which is one of the largest around here - about 2 hours drive from Melbourne.
It's a strange river. The photographs show it over a period of a day or two when it was running low. The Goulburn runs through cleared farmland and unlike most rivers around here has easy access.
In summer, especially in drought years, Victorian rivers heat up and dry up a bit. (Not always, last couple of years after ten year drought, we had summer floods.) So the fish go deep. Or die off if it's extreme. Which is why many of these rivers can only maintain small fish.
But the Goulburn is different. These photos show the river downstream from Eildon Weir which is an enormous artificial lake damming the Gouburn- built 50-60 years or so I think. Very deep. Down from the dam is the pondage which is a kind of buffer for releases from the dam. The pondage then releases into the river about 5 km up from the pics.
The releases into the pondage/river depend on irrigation needs of farmers on the banks of the Goulburn. And can happen very quickly - on one trip I was comfortably set up on a little peninsula in the middle of the pondage (seat, all the gear, flask and lunch) when one of these releases happened. I was knee-deep within 5 minutes and scuttled back to dry land.
The Goulburn levels can go from 100-150 MLD (mega litres per day) to 5000 MLD overnight. Rising and falling by 3 or 4 metres. The releases tend to happen during summer - when the growers need the water.
This results in the Goulburn behaving in the opposite way - upside down - to the other rivers because the water comes from deep in Eildon Weir and is considerably colder than surface water. So more oxygen inthe water, more active fish etc. The reverse happens in autumn and winter when the released water can be warmer than surface water.
Unfortunately, the river is easy to get to (and there's a handy pub, fish 'n' chips and a great fly shop - google the Goulburn Valley Fly Fishing if you're interested) and is heavily fished by bait plonkers and spinners as well as fly fishers which results in well educated fish - every brown trout in the river has a B.E. (bachelor's degree in entomology) with a post graduate diploma in how to avoid dumb fly fishers. You have to seriously match the hatch and be careful about presentation and creeping along the bank.
On the other hand, the river feeds several fish farms - brown and rainbow, some atlantic salmon - and these farms periodically stock the river. Every year or so, usually around the start of the season, they release I think up to abut 10,000 fish, mostly fingerlings but also a few hundred big uns. And two or three big fish are tagged - if you catch one of these, report it to the fisheries dept and you've won (I think I got this right) $A25,000 (about 18,000 pounds). They aren't caught every year but two years ago a 14-year-old kid caught one. Sure brings the tourists in.
Alan