Gone fishing !
Macquarie Perch
This week the Department of Sustainability and Environment has again been conducting its annual fish monitoring survey in the King Parrot Creek, funded this year by the Goulburn Broken CMA. We were fortunate to spend a morning with Jo and Renae, freshwater ecologists from the Arthur Rylah Institute, who are carrying out the survey, as they have for a number of years. They showed us all the various techniques they are using to capture and identify the fish. They are using both electro-fishing and Fyke nets at 5 locations between Flowerdale and Kerrisdale, with a particular focus on the Macquarie Perch (Macquaria australasica), a threatened species which is protected in all streams in Victoria except the Yarra River, which has an introduced population of the fish.
Electro-fishing involves applying a current through the creek water via a backpack generator. Fish are temporarily stunned, identified and recorded, and recover quickly after release. This technique has limitations, such as not being suitable for monitoring deep pools.
The Fyke nets are cylindrical with a series of supporting hoops, and internal partitions with access holes of decreasing size along the net away from the winged entrance. The other end is tied off and fixed above water so any platypus that is inadvertently trapped can breathe. These nets are left overnight and early in the morning the trapped fish are identified, measured and weighed. The Macquarie Perch, if large enough, are also tagged, and have a small piece of tail clipped for DNA analysis, before all the fish are released unharmed.
Two separate tags are used. A ‘T-bar’ tag, with a readable external flag showing its identification number, is inserted in the dorsal flesh. This tag also has a DSE phone number for anglers to report its capture (and claim a reward!). A second small ‘pit’ tag with a universally unique identifying number is inserted into the fish’s stomach. This tag can be electronically detected. Both tags can provide valuable information on fish movement up and down the creek.
When we left Jo and Renae, they were delighted with the results so far. It looks like being the highest tally of Macquarie Perch of any of their King Parrot Creek surveys, with sizes ranging from tiny ‘young-of-year’ up to almost 40cm long. We will let you know the final tally in a future post.
For a previous post on last year’s survey of Macquarie Perch (also known as ‘Macca’), click HERE.
Focus On Fauna 
Trackbacks