NSW Department of Primary Industries (DPI) fisheries scientists are investigating ways to boost the survival rates of fish caught and then released by anglers.Some guidelines designed to improve fish survival were recently developed for released line-caught snapper, silver trevally, mulloway, sand whiting, yellowfin bream and dusky flathead.
The research, costing more than $1.5 million and funded by NSW DPI and the Recreational Fishing Trust (using money from licence fees), is developing protocols designed to maximise fish survival via subtle changes to management practices.
Owing to bag limits, legal sizes and non-consumptive angling, between 30 and 50% of the total recreational catch is released each year in Australia. This amounts to more than 47 million fish being caught and released annually.
New research is now seeking to maximise the post-release survival of other commonly-caught species including luderick, sand mullet, garfish, tailor, Australian bass, Murray cod and golden perch.
NSW DPI scientists Matt Broadhurst and Paul Butcher have shown that mortality rates can be significantly improved through changed practices.
Key recommendations from an initial two-year project are that fishers should
-- Cut the line on fish that swallow hooks
-- Remove hooks caught in the fish’s mouth
-- Minimise air exposure
-- Use landing nets without knotted mesh
-- Maintain water quality in on-boat holding tanks, and
-- Use the right rig for the fish species being targeting.
Dr Broadhurst said some of these actions were found to massively boost fish survival.
“Simply cutting the line rather than attempting to remove hooks swallowed by mulloway and yellowfin bream increased their survival from 12 percent to more than 85 percent.
“Up to 76 percent of the released line-cut, gut-hooked yellowfin bream then shed their hooks over an average of three weeks”, he said.
Source: New South Wales Department of Primary Industries
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