Pots as alternative and sustainable fishing gears in the Mediterranean Sea: an overview

Abstract

Stock overexploitation, bycatch, discards and gear impacts on the environment are outstanding issues for Mediterranean fisheries. The adoption of alternative fishing gears is an appealing solution to ensure a more sustainable exploitation of resources. We discuss the pros and cons of pots as alternative gears by reviewing their main designs, spatial distribution and target species in the Mediterranean basin. We assessed the technical factors affecting the catch efficiency of the different pot designs for four target species: spiny lobster, Palinurus elephas; Norway lobster, Nephrops norvegicus; common octopus, Octopus vulgaris and pandalid shrimps, Plesionika spp. We found that pot volume is important to catch Octopus; mesh size to catch Nephrops and Plesionika; entrance surface to catch Octopus, Nephrops and Plesionika; pot shape/colour and entrance shape/position to catch Octopus and Plesionika; and bait type to catch Octopus and Nephrops. The literature review shows that pot fisheries have several considerable advantages over conventional gears, especially in terms of discards, bycatch, seabed impacts (particularly compared with bottom trawls and passive set nets), size and species selectivity, gear depredation, catch quality and gear cost, besides saving time and labour. Disadvantages hampering their wider diffusion include ghost fishing, a low catch of finfish species, the narrow range of species targeted by each pot design and the current early stage of research. These data make a clear case for using pots as alternative gears to traditional ones in the Mediterranean Sea in some areas and seasons to catch certain target species.

Effect of Extension Piece Design on Catch Patterns in a Mediterranean Bottom Trawl Fishery

“…The modification of standard trawls to decrease unwanted size and species retention is one of the most intensively investigated approaches in Mediterranean bottom trawl fisheries in light of the landing obligation regulation (EU, 2013), which encourages the adoption of technical solutions to reduce discards (Petetta et al, 2021). The aim of the present study was to test, in the extension piece section, simple technical modifications, the efficacy of which has been demonstrated at the codend level (Wienbeck et al, 2011;Sala et al, 2016).…”

Fish vulnerability to capture by trapping is modulated by individual parasite density

“…Passive gears, such as pots/traps, are considered more environmentally friendly methods of fishing compared to gears such as trawls, which have a high energy consumption, significant habitat impacts and high bycatch levels [88]. Pots/traps have shown to be viable in several demersal fisheries including species such as pacific cod ( Gadus macrocephalus ), sablefish ( Anoplopoma fimbria ) and groupers [35,88,89]. Yet, almost nothing is known on how selection on behavioural or physiological traits in trap fisheries may occur.…”

Using fish behavior to design a fish pot: Black seabream (Spondyliosoma cantharus) case study

“…On the other hand, the adoption of this type of gear relies on the yield and market opportunities for fishers. Pots generate low discard rates compared to many other gear types (Petetta et al, 2021). Developing fish pots would help fishers to cope with new gear constraints due to the multiplication of maritime usages such as wind farms (Yates et al, 2015;Stelzenmüller et al, 2021) and marine protected areas (Cadiou et al, 2009).…”