Part of the DEPI’s big wild trout fisheries program (https://flystream.com/video/all-about-victorias-big-wild-trout-fishery-project/) includes investigating the response of stream trout to elevated summer water temperatures. In particular, researchers want to know if some wild trout migrate when the water gets too warm, and if so, where they go and how warm the water needs to be before they move?
To get this part of the program underway, Arthur Rylah Institute staff have been hard at work capturing wild trout in the Delatite River, anesthetising them, inserting acoustic tags and returning the fish to the water unharmed. This stage of the study is off to a flying start, with over 100 resident brown and rainbow trout implanted with tags and returned over tens of kilometres of river.
Each fish’s acoustic tag produces a unique signal, so over coming months and years, researchers will be able to track the movement of each trout as it passes a number of electronic ‘listening posts’ set up at strategic points along the river. Hopefully, this will give us our the best understanding yet of this aspect of wild trout behaviour in north-east Victorian rivers; in turn providing Fisheries with a crucial piece of the information puzzle to help them better manage the fishery.
Meanwhile, if you happen to catch a Delatite trout marked with a dorsal fin tag, it would be great if you could carefully return it to the water – the more tagged trout swimming around, the higher the quality of information. Even better, before releasing the fish record its length, the tag number, location & date of capture and phone these details through to 1800 134 093.