Sublethal effects of angling and release on golden perch Macquaria ambigua: implications for reproduction and fish
K C Hall1, M K Broadhurst1, P A Butcher1
1New South Wales Department of Primary Industries, National Marine Science Centre, PO Box 4321, Coffs Harbour, NSW, 2450, Australia.
Abstract:
The present study tested the hypothesis of no delayed sublethal effects of mild angling and release on the feeding, growth, somatic condition and gonadal development of golden perch Macquaria ambigua during gametogenesis. Subsamples of adult M. ambigua (n = 17-21 of 207), originally captured from the wild and stocked into ten 0·1 ha earthen ponds, were angled and released during early and late gametogenesis. Wild samples that were concurrently collected throughout the experiment underwent rapid and synchronous gonadal development and many spawned. While no spawning occurred in the ponds, most M. ambigua underwent normal gonadal development to maturity, including the angled fish. Angled fish also fed, maintained condition and actually grew faster than non-angled captive controls. Although females that were angled during late gametogenesis more readily ingested and retained baited hooks, neither their subsequent condition nor gonadal development was significantly affected. The predominance of null results was attributed to the combined effects of the flexible reproductive strategy of M. ambigua, the benignness of mouth hooking and immediate release, and possible methodological issues arising from differential hooking success of more aggressive and resilient individuals. The findings support earlier catch-and-release research, but contrast with reports of acute reproductive effects following capture and handling for aquaculture broodstock. This discrepancy highlights the need for research to specifically address welfare questions relevant to recreational fisheries across various species and angling scenarios.
