The diet and feeding behaviour of the forkbeard Phycis phycis was studied based on 246 stomachs collected between May 2011 and April 2012 from a commercial fleet operating off the central west coast of Portugal. A total of 44 prey items were identified in the stomachs which were merged into major groups to avoid problems with low expected frequencies. The following taxonomic categories were considered: non-decapod Crustacea, Caridea, Anomura, Munida spp., Processa spp., Brachyura, Pisces, Trisopterus luscus. In order to investigate possible diet differences between fish size classes, a cluster analysis was performed using the mean abundance of each prey group by forkbeard 5 cm length class, and three length groups (LG) were obtained: <22.5, 27.5–37.5 and >42.5 cm. Seasonally, Caridea was the main prey group during winter and autumn while Pisces was predominant during the rest of the year. Caridea was the most important prey group for LG1 and LG2 while in LG3 Pisces was the principal one. The forkbeard feeding behaviour may be characterized as presenting a shift pattern from a more generalist diet (small Crustacea, mainly Caridea) in the young adults to a more specialist strategy (teleosts) in the adults.

The forkbeard, Phycis phycis, is an important commercial species in Portugal; however, little information is available on its biology. Age and growth of the forkbeard from Portuguese continental waters were studied using 687 otoliths from specimens caught between May 2011 and December 2012. Otoliths were transversally sectioned, and assigned ages were validated by marginal increment analysis and edge analysis, and indices of precision were also calculated to corroborate ageing within and between readers. Validation techniques showed that an annual growth increment is formed every year, corresponding to the succession of an opaque and a translucent growth zone. Specimens ranged from 15.5 to 67.1 cm total length (TL), and their estimated ages ranged between 0 and 18 years. The forkbeard is a relatively slow growing, long lived species, that does not show sexual dimorphism in growth. The von Bertalanffy growth parameters estimated for forkbeard from the Portuguese continental waters were L∞ = 75.14 cm TL, k = 0.10 yr−1 and t0 = −2.09 yr.

The forkbeard Phycis phycis is one of the main target species of the demersal fishery in the Azores, north-eastern Atlantic. Age and growth of the forkbeard were studied using 477 otoliths from individuals caught between April 2000 and August 2004. Otoliths were burned and sectioned, a preparation method that improved the easiness of readings. Individuals ranged from 21 to 71 cm in total length, and their estimated ages between 2 and 18 years old. Forkbeard is a relatively slow growing, long lived species, that does not show sexual dimorphism in growth. The von Bertalanffy growth parameters estimated for the Azorean forkbeard were L∞ = 79.64 cm, k = 0.09 yr−1 and t0 = −1.88 years.