For Further Reading ...
Suzanne Ayvazian Ph.D.
Research Scientist
Estuarine and Coastal Finfish Section
Western Australian Marine Research Laboratories, PO Box 20, North Beach, WA 6020, Australia
Making a decision to use a single or treble hook involves consideration of the different handling times, hooking efficiency and mortality rates associated with each hook type. A review of the literature has shown, generally, that longer handling times are expected for fish caught with treble hooks than single hooks. This is due to the difficulty in releasing multiple hook penetrations and the associated stress on the fish. The longer handling times will impact on the survival prospects for the fish. There has been limited research on the hooking efficiency of single versus treble hooks. One study reported 41.9% of coho salmon hooked on treble hooks were lost compared to 33.3% for single hooks. However this level of difference did not produce a significant result.
It has been suggested that while the retention of fish on single hooks versus treble hooks may not be different, treble hooks may be beneficial as they produce lower mortality rates.
While the issue of hook choice and mortality rates is still inconclusive, it appears that the lower mortality rates reported from treble hooks compared to single hooks may be due to the way they operate. Single hooks will be swallowed deeper penetrating vital organs and causing massive bleeding. Treble hooks, due to their configuration will generally, lodge in the mouth causing many superficial injuries. However, there is nearly 100% mortality if treble hooks become tangled in the gills.
Many studies support these observations. Striped bass mortality was 13% for single hooks as compared to 3% for treble hooks
Walleye mortality was higher for fish caught with baited single hooks as compared to treble hook artificial lures
There are also many studies that indicate the mortality rates are similar using these two gear types. Mortality rates of the recreationally important red drum caught on single and treble were similar (4.9% versus 3.3%) as were the rates for spotted seatrout caught on single (4.7%) and treble (10%) hooks
Analysis of 18 hooking mortality studies on trout demonstrated no difference in mortality rates between single and treble hooks
However, a recent study on bluefish carried out in Australia showed that treble hooks had a higher rate of mortality compared to single hooks
Then there is the question about the benefits of using a barbless versus a barbed hook. Several studies from freshwater fisheries have compared the mortality rates between these hook types and have shown, in general, the extent of tissue damage and subsequent bleeding associated with hooking and subsequent mortality is lower for barbless than for barbed hooks
Research information from lake trout studies showed that while overall mortalities were similar for barbless (6.9%) and barbed hooks (7.0%), barbed hooks produced greater bleeding from tissue damage
A study on coho salmon showed the majority of fish caught with barbless hooks were hooked in the jaw (78%) while 44% of fish caught with barbed hooks were hooked in the gills. This lead to a greater mortality for fish caught with barbed hooks (78%) compared to barbless hooks (33%)
In marine waters, little research has been conducted on the potential benefits of using barbless hooks. Bluefish research in Australia has shown similar overall mortality rates for fish caught with barbed (1.9%) and barbless hooks (2.8%)
In summary, the majority of the research evidence indicates that single barbless hooks will cause less mortality and injury than treble hooks and may be the hook type of choice in order to maximize the benefits of catch and release for fish stocks.
References:
Lasater, J. E. and Haw, F. 1961. Comparative hooking mortality between treble and single hooks on silver salmon. Pac. Mar. Fish. Comm. Bull., 5: 73-76.
Muoneke, M. I. and Childress, W. M. 1994. Hooking mortality: A review for recreational fisheries. Reviews in Fisheries Science, 2(2): 123-156.
Diodati, P. J. 1991. Estimating mortality of hooked and released striped bass. AFC-22. National Marine Fisheries Service.
Payer, R. D., Pierce, R. B. and Pereira, D. L. 1989. Hooking mortality of walleyes caught on live and artificial baits. N. Am. J. Fish. Manage., 9: 188-192.
Matlock, G. C., McEachron, L. W., Dailey, J. A., Unger, P. A. and Chai, P. 1993. Short-term hooking mortalities of red drum and spotted seatrout caught on single-barb and treble hooks. N. Am. J. Fish. Manage., 13: 186-189.
Taylor, M. J. and White, K. R. 1992. A meta-analysis of hooking mortality of nonanadromous trout. N. Am. J. Fish. Manage., 12: 760-767.
Ayvazian, S. G., Wise, B. S. and Young, G. C. Short-term hooking mortality of tailor (Pomatomus saltatrix) in Western Australia and the impact on yield per recruit. Fish. Res. (submitted).
Falk, M. R., Gillman, D. V. and Dahlke, L. W. 1974. Comparison of mortality between barbed and barbless hooked lake trout. Tech. Rep. Ser. CEN/T-74-1. Winnipeg, Manitoba: Canada Department of Environmental Fisheries and Marine Service.
Milne, D. J. and Ball, E. A. R. 1956.The mortality of small salmon when caught by trolling and tagged or released untagged. In: Progress Reports of Pacific Coasts Stations, No. 106, pp. 10-12. Nanaimo, British Columbia: Fisheries Research Board of Canada.
