Scientific African (Nov 2022)
An evaluation of the deep-sea catch in the Mediterranean Sea, Egypt regarding pattern of CPUE, diversity, Sharks, and discards
Abstract
Deep-sea fisheries suffer from the very low studies and attentions in the Egyptian water of the Mediterranean Sea in spite of its importance in the other parts of the Sea for the fisheries economy and biodiversity. In this study, the pattern of deep-sea catch in the eastern part of the Egyptian Mediterranean coast, in terms of the catch per unit effort (CPUE), diversity, Sharks, and discards, was investigated using two commercial fishing vessels between 2017 and 2018 to support the unknown data on deep-sea habitats and put the Egyptian country on the map for current and future deep-sea exploring and management. The fishing operations were constructed at depths ranging from 350 to 800 m. The resulted data of the catch were separated into targets, bycatch, and discards based on a trip. Total annual catch was 17478.09 kg, both targets and by-catch accounting for 15903.09 kg and a percentage of 90.99 % (targets 69.92 %; bycatch 21.07 %), while the discards accounted 1575.00 kg (9.01 %). Seasonally, the highest total catch was during summer (6637.50 kg;37.97 %), while the lowest was in autumn (1962.29 kg; 11.23 %). CPUE/trip were as follows: target (19.81± 8.85 kg), bycatch (6.96±2.49 kg), and discards (5.51±2.78 kg). The diversity included four species of red shrimp (Aristaeo morpha foliacea, Aristeus antennatus, Plesionika edwardsii, and Parapenaeus longirostris) as the main targets in a percentage of 8.89 % together. The highest abundant was A. foliacea (48.73 %), it was measured from 8.5 to 23.5 cm (TL) and weighed from 8.1 to 58.6 g, with its majority in winter, followed by A. antennatus (14.99 %), with the majority in spring, while P. longirostris (2.65 %) was the least abundant. Bycatch comprised of 23 species, (8 cartilaginous;12 bony fishes; 3 cephalopods). The major fish species was M. merluccius (15.162 %), its highest season was autumn (16.804). Discards comprised of 18 species (5 cartilaginous species;11 bony fishes,1 Decapoda, and 1 starfish). This study has confirmed Heptranchias perlo and bony fish Lophius budegassa, while the squid Histioteuthis bonnellii, Decapoda Polycheles typhlop, Sea star Ceramaster grenadensis, were recorded here newly. The findings highlighted the significance of the insufficient data on deep-sea fisheries for commercial and biodiversity purposes, recommending the continuous updating, monitoring for further management.
