Hook performance and selectivity of Eurasian perch, Perca fluviatilis (Linnaeus, 1758) in the ￃ land Archipelago, Finland

Summary The effects of two hook-types (circle or J hook) fished with two different baits (red worms Eisenia spp., or cyprinid fishes) were examined for deep-hooking, catch rate, mean total length, and selectivity of Eurasian perch, Perca fluviatilis, in the Åland Archipelago, Finland. The perch population available to hook-and-line gear was sampled with multipanel gillnets, with panels ranging from 10 to 60 mm in stretched mesh diameter. The effect of each hook then was examined for each bait by conditioning the size distributions of hook-and-line catches on the size distribution of perch collected with gillnets to estimate selectivity. The proportion of deeply-hooked perch was 4.8 times greater for J hooks (0.21) than circle hooks (0.04) baited with worms and 3.7 times greater for J hooks (0.33) than circle hooks (0.09) baited with fish. Catch rates were significantly different between the two baits but not between the two hooks, with the greatest catch rate observed for the circle hook baited with worms. There was no significant difference in perch total length between the two hooks, but there was a significant difference between the two baits, with the fish bait catching significantly larger perch. Perch selection peaks between the two hooks differed by only 13.8 mm, but the selection peak with fish bait (236.4 mm TL) was 119.9 mm greater than the selection peak with the worm bait (116.5 mm TL). A substantially lesser incidence of deep hooking support the conservation benefits of circle hook use for perch, especially when catch-and-release is practiced. Using fish baits similar in size to those used in this experiment can avoid potentially harmful interactions between relatively small perch and anglers who place little importance on catch motives but whose satisfaction is still catch-dependent.