Damage to Common Octopus (Octopus minor) Caught in Pot Fisheries

Beyond continual reductions in catch, common octopus frequently suffer damage during pot fishing, which can reduce the quality of the product and consequently, its value. This study evaluated how pots with different mesh sizes affect the integrity of common octopuses captured by commercial fisheries. Experimental fishing was conducted in Taean-gun and Incheon-si using pots with different mesh sizes (16.3, 18.3, and 22.4 mm). Common octopuses were classified as either damaged or undamaged based on whether the number of injured arms exceeded a specific threshold value, and logistic regression was applied to estimate the probability of damage, based on the mesh size and region. Smaller mesh sizes significantly reduced the damage in common octopuses and increased the catch effectiveness; however, the degree of impact differed according to the region. This study provides quantitative estimates of the mesh sizes associated with specific damage probabilities, offering a scientific basis for refining regionally tailored management practices. By reducing the mesh size from the current legal standard of 22 mm to 16 mm, the probability of damage that leads to a decline in commercial value (i.e., threshold = 2) is projected to decrease from 77.8% to 46.5% in Taean-gun, and from 93.4% to 39.3% in Incheon-si.