Rising Water

I’d forgotten what it’s like to actually hope it won’t rain, at least for a few days! In 2014 and 2015, no such indulgence was permitted. Our average annual rainfall here around Millbrook is about 800 mm but the last two years each struggled to make 600 mm. The 400 mm deficit really showed and by this year we needed some decent precipitation – and we’ve had it. So far in 2016 the gauge has collected 420 mm, and for the first time in 3 years, I’m thinking about what I call floodwater feeders – the kind of lake fishing that’s generated by water rising over long-exposed margins. The same situation is evolving from the Snowys to Tasmania.

Thanks to two dry years, last year's grass below the high water mark at Moorabool Reservoir has had a chance to grow some more.

Thanks to two preceding dry years, the grass below the high water mark at Moorabool Reservoir has had a chance to grow some more.

Oddly enough, for quality floodwater feeder fishing, you actually want it dry for quite a while before the big rain arrives – several months at a minimum; a year or two is even better. You need the grass to grow, and the terrestrial bugs to move in. Picture a smiling real estate agent… ‘Floods? Nah, the water never gets up here – perfect place to raise a family of little beetles!’

Those dark specs are drowning beetle larvae as a lake at Millbrook starts to flood long-exposed ground. The longer the edges have been dry, the more food is likely to be flushed.

Those dark specs are drowning beetle larvae as a lake starts to flood long-exposed ground. The longer the edges have been dry, the more trout food is likely to be flushed out.

Ideally, we want the water to rise steadily over this ‘new ground’. Too fast and the trout are spoilt by vast quantities of flooded-out food and they don’t need to brave the shallows right at the edge of the rising tide – there’s more than enough to eat in the safety of deeper water. However if the rise is too slow, most of the caterpillars, worms, beetles, earwigs, spiders etc. can outpace it. The perfect rate of rise depends on things like shoreline gradient, but from a couple to several centimetres a day of vertical rise is handy.

Fantastic but fleeting floodwater fishing at Little Pine Lagoon. The difference between minimum & maximum  level is too small for sustained sport. By the next day, the lake was stable again and the flushed spiders etc.  were gone.

Fantastic but fleeting floodwater fishing at Little Pine Lagoon. At this lake, the difference between minimum & maximum level is too small for sustained sport. By the next day, it was stable again and the flushed spiders were gone.

The best chance for continuous opportunities tends to apply to those trout lakes which are large compared to their catchment, and which are designed to store ‘excess’ water during wet periods, then release it when it’s dry. Obviously you need these lakes to have a retained enough water for trout survival during the dry times, and you also want plenty of gently sloping, relatively fertile shores (not sand or rock) that can revegetate well when the lake is low. My favourites include Tullaroop and Upper Coliban in Victoria, Tantangara and Eucumbene in New South Wales, and Lake Echo in Tasmania – but there are dozens more.

This graph of Snowy lake levels is also a history of when the floodwater feeder fishing was best!

This graph of Snowy lake levels is also a history of when the floodwater feeder fishing was best!

Often, true floodwater feeders are quite opportunistic and will take a range of flies fished inert either on the bottom, under an indicator, or dry – though keep an eye out for ‘booms’ of one particular type of flooded bug. These episodes can encourage selective feeding and the need for a correct imitation. Regardless of fly, don’t move it except for perhaps for the slightest twitch to attract the trout’s attention – drowning bugs are  basically helpless and by definition can’t swim.

Steve had to chase this Tantangara floodwater feeder out into the lake to avoid getting snagged on the drowned bushes.

Steve had to chase this Tantangara floodwater feeder out into the lake to avoid getting snagged on the drowned bushes.

Look for floodwater feeders on cloudy days or at first and last light. In the Tasmanian highlands and occasionally in the Snowys, the shallows may simply be too icy for action very early in the season. Elsewhere winter and right through to mid/late spring can work.  Finally, don’t expect the trout to be easy to see. They like the food, but hate the exposure and even big trout will hardly disturb water mere centimetres deep. Scan likely shores until your eyes hurt!