Water

‘A slimy circle of life’

By Country News

To most of us, the green slime that gathers on sticks, logs and rocks in our rivers is simply something we keep away from to avoid slipping and falling in.

However, when it comes to the health of our rivers, there is nothing more important than slime according to North Central Catchment Management Authority manager Trent Gibson.

During summer, slime that is sitting out of the water can dry off and die, and slime that is in water for too long becomes unappetising for water bugs and loses its nutritional value.

‘‘Managing slime is a real balancing act, but one that is vital for the health of the river,’’ Mr Gibson said.

‘‘Slime that is scoured off a rock or a log by flowing water regrows almost immediately.

‘‘When it regrows, it is much more appetising and nutritious for water bugs. The more fresh, growing slime there is, the more water bugs there are, and the bigger and stronger those water bugs become.

‘‘The more water bugs there are, the more fish, water rats and platypus there are. It really is a slimy circle of life.’’

If water levels remain low the slime dries off and dies and is inaccessible to water bugs.

The North Central CMA will manage a 472Ml flow down the Loddon River and Serpentine Creek in the coming weeks, with one of the aims keeping the slime and the bugs, fish, platypus and water rats alive.

‘‘If we didn’t do these flows, the water bug population would be very poor, which would affect the populations of native fish and platypus,’’ Mr Gibson said.

‘‘Summer flows are really important for rivers, especially in this part of the world.

‘‘These flows will capitalise on the recent spring water for the environment flows and help minimise the risk of toxic blackwater events during the hottest part of the year.

‘‘Our spring flows washed lots of the leaf litter away, which is the first step in preventing blackwater.

‘‘These flows will keep the water moving and connect the water between pools.’’

The flows are also aimed at improving water quality along the waterways and giving vegetation on the banks and emerging from the water a much-needed drink.

Up to 100Ml a day will flow down the Loddon from Cairn Curran to the Murray for up to three days, with up to 40Ml a day will flow down Serpentine Creek for up to three days.

‘‘Once this water hits the Murray it goes back into the consumptive pool,’’ Mr Gibson said.