From trap to nursery. Mitigating the impact of an artisanal fishery on cuttlefish offspring

• Published in: PloS one 2014-02, Vol.9 (2), p.e90542-e90542
• Main Authors: Melli, Valentina, Riginella, Emilio, Nalon, Marco, Mazzoldi, Carlotta
• Format: Article
• Language: English
• Subjects: Adults; Animal behavior; Animals; Biology; Boats; Breeding; Breeding seasons; Coastal zone; Coasts; Commercial fishing; Conservation; Conservation of Natural Resources - methods; Conservation of Natural Resources - statistics & numerical data; Data Collection - methods; Decapodiformes - physiology; Eggs; Female; Fish; Fisheries; Fisheries - methods; Fisheries - statistics & numerical data; Fishing; Fishing (Recreation); Fishing vessels; Geography; Habitats; Hatching; Human influences; Humans; Interviews as Topic; Italy; Life cycle engineering; Life cycles; Marine resources; Mitigation; Oceans and Seas; Offspring; Overexploitation; Ovum - physiology; Protection and preservation; Resource conservation; Resource management; Sepia officinalis; Substrates; Surveys; Traps
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0090542

Overexploitation and the impact of several types of human activities have caused declines of marine resources. The direct and active involvement of fishermen in the management of marine resources is effective not only for resource conservation, but also for changing fishermen's attitudes. In this study, we proposed and tested the efficacy and suitability of a measure for mitigating the impact of a trap fishery on cuttlefish eggs in the North Adriatic Sea. This measure directly involves fishermen in promoting the conservation of the early, and more vulnerable, stages of the cuttlefish life cycle. Through surveys on fishing boats and interviews with fishermen, we found that traps placed in coastal areas during the cuttlefish breeding season have a high impact on cuttlefish eggs, with over 3 million eggs likely being destroyed by 3750 traps of 15 fishermen in less than 3 miles of coast. The use of removable ropes attached inside traps as an additional substrate for egg deposition allowed the recovery of 23.7% of the eggs deposited on the traps on average, without affecting the catch rate of adults. Experiments examining hatching success in the field highlighted the need for a careful choice of hatching sites to maximise the efficacy of the mitigation measure. The proposed mitigation measure reduced the impact of fishing on cuttlefish eggs, with no significant effect on the commercial catch. Fishermen showed a positive attitude towards the application of this measure, which is inexpensive and easy to employ. The direct involvement of fishermen in the management of this resource and the maintenance of traditional fishing methods are a novel aspect of the proposed measure and represent the basis for its success.