Effect of Bait Type and Bait Size on Catch Efficiency in the European Hake Merluccius merluccius Longline Fishery

We investigated the effect of bait type and bait size on the catch ef
fi
ciency of a demersal longline
fi
shery targeting
European Hake
Merluccius merluccius
in the North Sea. Automation of the labor-intensive processes onboard
fi
shing
vessels requires
fi
nding alternatives to the traditional bait used in the
fi
shery (i.e., whole European Pilchard
Sardina
pilchardus
). Of the six alternative baits investigated, four resulted in signi
fi
cant reductions in catch ef
fi
ciency ranging
from 32% to 90%. Only chopped Atlantic Herring
Clupea harengus
was a reasonable alternative bait, with an esti-
mated non-signi
fi
cant loss of only 2.12% in European Hake catch ef
fi
ciency. Our results demonstrated that choice of
bait type and size can affect the catch ef
fi
ciency of different sizes of European Hake. Thus, the choice of bait may
also affect the size distribution of the catch. The latter highlights the importance of considering
fi
sh size when infer-
ring the effect of bait choice on the catch ef
fi
ciency of longline
fi
sheries.