Seabird interactions with longline gear can often lead to bycatch events as birds become hooked or tangled. Since seabirds rely heavily on their sense of smell (olfaction) to locate food, noxious bait has been proposed as a strategy to help avoid such events. Noxious bait is treated to make it unpalatable to non-target species (in this case seabirds). Similarly, dripping olfactory deterrents such as shark liver oil behind fishing vessels has been suggested and trialled to deter non-target species.
Trials carried out in the New Zealand snapper longline fishery employed this technique, by dripping small amounts of school shark liver oil onto the ocean surface directly astern the boat. This simple, low-cost technique successfully reduced the number of seabird interactions with the boat. Widespread applications and the possibility of seabirds habituating to the smell are yet to be studied.
This page was last updated on 12.02.21.
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