Species composition and population structure of devil rays (Mobula spp.) in artisanal fisheries of Guatemala's Pacific coast

Incidental capture of devil rays (Mobula spp.) occurs in several artisanal fisheries worldwide, yet biological information from many regions remains limited. This study examines species composition, morphometrics, sex ratio, and sexual maturity of devil rays incidentally captured in artisanal fisheries along Guatemala's Pacific coast. Fishing operations were monitored from February 2019 to February 2020 and from October 2022 to February 2024, including 246 fishing trips, 143 of which recorded mobulids. Data on species identification, disc width, total length, sex, and maturity stage were collected from landed individuals. A total of 453 devil rays were recorded. Of these, 447 were identified to species level: Mobula munkiana (n = 238), M. thurstoni (n = 205), M. mobular (n = 3), and M. birostris (n = 1); the remaining six individuals could only be identified to genus level (Mobula spp.). Of the total captures, 40.4% occurred in small-scale fisheries targeting Caranx caballus, 32.6% in fisheries targeting large pelagic species, and 27.0% could not be assigned to a specific fishery. In M. thurstoni, males exhibited a significantly larger mean disc width (131.78 ± 32.28 cm) than females (105.14 ± 26.46 cm; P < 0.05), with a male-biased M:F sex ratio of 2.01:1 (χ² = 22.56; P < 0.05). Similarly, in M. munkiana, males were significantly larger (89.27 ± 10.28 cm) than females (82.12 ± 10.52 cm; P < 0.05), and the sex ratio was also male-biased (1.64:1; χ² = 13.65; P < 0.05). These findings provide baseline information on species composition and morphometrics relevant to fisheries management and devil ray conservation.