Increasing biological knowledge for better management of by-catch species: Age, growth, and mortality of piper and red gurnards (Teleostei: Triglidae)

• Published in: Scientia Marina
• Main Authors: Sequeira, Vera, Sousa, Inês, Neves, Ana, Vieira, Ana Rita, Silva, Elisabete, Silva, Frederica, Duarte, Ana Marta, Mendes, Susana, Ganhão, Rui, Assis, Carlos, Rebelo, Rui, Magalhães, Maria Filomena, Gil, Maria Manuel, Gordo, Leonel Serrano
• Format: Article in Journal/Newspaper
• Language: English
• Published: Consejo Superior de Investigaciones Científicas 2023
• Subjects: By-catch; Age determination; Growth curves; Fishing mortality; Longevity; Chelidonichthys cuculus; Trigla lyra; Captura incidental; Determinación de la edad; Curvas de crecimiento; Mortalidad por pesca; Longevidad; Northeast Atlantic
• Online Access: http://hdl.handle.net/10400.8/8777; https://doi.org/10.3989/scimar.05308.060

This study was partially supported by the European Maritime and Fisheries Fund MAR2020 (“VALOREJET: Valorização de espécies rejeitadas e de baixo valor commercial”, grant MAR-01.03.01-FEAMP-0003) and by the Fundação para a Ciência e Tecnologia (strategic project, UID/MAR/04292/2019; V.S., contract number CEECIND/02705/2017; A.R.V., contract number EECIND/01528/2017). Gurnards are a valuable by-catch of mixed demersal fisheries and are commercially important in European waters, but they are often discarded, reported under “mixed gurnards” and with incomplete biological information by species. In the present work, a total of 558 piper gurnard specimens of between 10.9 and 44.4 cm (1 to 11 years) and 425 red gurnard specimens of between 10.2 and 42.1 cm (0 to 9 years) from the northeast Atlantic (Portuguese) coast were used to study age and growth. The von Bertalanffy growth parameters for piper gurnard were estimated through the combination of whole-otolith readings and back-calculation (L∞=44.7 cm, k=0.16 yr–1 and t0=–2.781 yr). For red gurnard the same growth parameters were estimated using whole-otolith readings (L∞=40.2 cm, k=0.28 yr–1 and t0=–1.074 yr). The results indicate that the red gurnard reaches a smaller length, although it grows faster than the piper gurnard. Natural, instantaneous and fishing mortalities were estimated as well as the exploitation rate for both species. For the Portuguese coast, the red gurnard showed a higher fishing mortality and exploitation rate than the piper gurnard, raising concerns about its sustainable management. Los rubios son una captura incidental valiosa de las pesquerías demersales mixtas y comercialmente importantes en las aguas europeas, pero a menudo se descartan, se informan como “rubios mixtos” y con información biológica incompleta por especie. En el presente trabajo se han recogido un total de 558 ejemplares de ganeo, de entre 10,9 y 44,4 cm (1 a 11 años), y 425 individuos de arete, de entre 10,2 y 42,1 cm (0 a 9 años) procedentes del Atlántico nororiental ...