Common octopus

There is limited information on the population structure or stock status of this species in European waters. Octopus abundance varies widely from year to year with no clear trends, and is sensitive to environmental influences. Current issues with the common octopus fisheries, in several countries (including Spain (Galicia) and Portugal (Algarve)) include excessive effort, illegal fishing, exploitation of undersized octopus, and lack of effective surveillance and monitoring and control of the fishing activity, as well as the general lack of routine assessment of stock status. Thus, there is concern for fishing pressure within this region. Common octopus have high resilience to fishing pressure.

Octopus are mostly landed in southern Europe and comprise mainly of Common octopus (Octopus vulgaris). The species is one of the main cephalopods of commercial interest in European waters; of high profile and have high fisheries value.

There is no routine assessment of common octopus stocks in European waters. The applicability of assessment methods for these stocks is limited by inadequate and inaccurate statistical information and because most catches are made as bycatch in finfish fisheries. Survey abundance indices for octopus (common octopus; horned octopus - Eledone cirrhosa; and musky octopus - Eledone moschata) within the area, show wide year-to-year fluctuations but no clear trends are evident. Abundance trends revealed by commercial LPUE and survey CPUE follow similar trends in some areas. Recent high LPUE values for Octopodidae by Basque trawlers may reflect increased targeting of cephalopods.

The sensitivity of octopus to environmental influences (such as variations in temperature and salinity/rainfall), results in natural inter-annual variability of abundance.

The exploitation of the common octopus in Portugal has more than doubled over the last 30 years. However, common octopus landings in the Algarve have been decreasing over the last few years and have remained below the historical mean since 2014. Despite this, there is an increasing economic dependence on this species in the Portuguese small-scale sector, especially in the Algarve. In Spain (Galicia) octopus represent 80-90% (by weight) of the total catch of the small-scale fleet (mainly using traps). According to official statistics, landings have been decreasing in recent years with a drop from 4,100 tonnes in 2010 to 2,100 in 2019. This decrease is suggested to be related to a combination of overfishing, ineffective monitoring and control and environmental variation.

The annual average landings, in Northeast Atlantic, for the 2000 “2018 period for octopus (i.e. common octopus; horned octopus; and musky octopus) was 14,279 tonnes; minimum in 2006 (9,003 tonnes) and maximum in 2013 (21,652 tonnes). Landings of octopus reported to ICES are not disaggregated by species.

Octopus fisheries are likely to continue to grow in importance and magnitude as many finfish stocks are either fully or over-exploited.

Populations of common octopus in southern Spain and Portugal are considered to be genetically related but northern Spain or the Canary Islands are differentiated from the others. Therefore, a biological stock is considered within the Southern Iberian Peninsula (ICES area 9a-South, Gulf of Cadiz, which includes South of Portugal and Spain) where an assessment unit is well recognised. There is no formal assessment of the resource at the stock level, only a survey in Spanish waters.

Most octopuses are landed by small-scale fisheries and the activity is mainly regulated at the regional level; the level of participation of the fishing industry in the management of their activity varies. Current issues with the common octopus fisheries in several countries (including Spain (Galicia) and Portugal (Algarve)) include excessive effort, illegal fishing, exploitation of undersized octopus, and lack of effective surveillance and monitoring and control of the fishing activity, as well as the general lack of routine assessment of stock status.

Octopus in Europe are not subject to quota limits and there is no routine assessment of stock status to inform management decisions. There is a statuary minimum legal weight of 750 grams applied to common octopus in EU waters. However, common octopus becomes sexually mature at different sizes. In Northeast Atlantic studies, BW50% (body weight at which 50% of the population is sexually mature) at first maturity was estimated at 1858.6 g for females in one study, and 1788 g for females and 903 g for males in another. Therefore, the current legal weight limit offers inadequate protection to the spawning stock and increases the probability of recruitment overfishing.

In the Northeast Atlantic most octopus are fished by Spain and Portugal in Division 9a and 8c, with common octopus being the main species caught. Catches are concentrated in Division 9a; on average 85% of the total octopus' landings in the Northeast Atlantic are taken from this division.

Common octopus' fisheries in Portugal and Spain are subject to a range of fishery legislation. The management regimes in both locations involve both input and output control measures, as well a suite of other technical measures. Input controls consist mostly of setting gear limitations (e.g., number of traps/pots nets deployed, gear design) and limiting the number of licenses. Output controls consist mostly of limiting the weight of the octopus specimens landed, varying between 750 g (Portugal) and 1000 g (Spain). Galicia has several other output controls in place; maximum fishing quota per vessel and daily catch limits. Both countries also have several other technical measures in place, some of which are common to the regions and some specific. Some management arrangements in place are tailored at the local level and, in Galicia fishers actively participate in the management of their activity.

In Portugal, octopus fisheries management derives from a combination of EU and national general and specific legislation. The common octopus fishery faces several challenges including those inherent to the biological feature of the species and its sensitivity to environmental influences. Limited understanding about the resource has led to inappropriate monitoring and assessment, and a lack of intervention by authorities in the management of octopus. Compliance with rules and regulations in the Algarve is low and the effectiveness of the monitoring and control system at sea and on land is very limited, which results in the number of traps deployed being effectively under no control and reducing the efficacy of the minimum landing weight legislation.

The management of the octopus fishery in Galicia (Spain) is more comprehensive and includes annual management plans for the octopus fishery. The most recent management plan established the rules for the octopus fishery for the 2020 “2021 season, and includes, amongst other measures, closed seasons (from May 29th to July 1st, 2020), minimum weight of catches (currently 1 kg), maximum daily catches taking into account the number of crew members on-board of the vessel, and the number of traps per working hour at sea. Despite the management in place, a decline in octopus landings has been observed over recent years in Galicia which is thought to be partly due to overfishing and ineffective control of rules and regulations.

There is a substantial amount of illegal commercial catch, which had been estimated to range between 20 “50% of the total reported catches in Galicia 2010, and a significant number of recreational fishers selling octopus directly to restaurants, illegally (illegal selling out the official auctions). However, in Galicia, better control and monitoring programs appear to have contributed to a substantial reduction of illegal practices over the last few years, and advances in co-management have increased compliance with regulations.

Octopus discards are negligible in Division 9a (0.2%: 2018) and 8c (1.1%: 2018).

Both the EU and UK have fishery management measures in place, which can include catch limits, targets for population sizes and fishing mortality, and controls on what fishing gear can be used and where. In the EU, compliance with regulations has been variable, and there are ongoing challenges with implementing some of them. There was a target for fishing to be at Maximum Sustainable Yield by 2020, but this was not achieved. The Landing Obligation (LO), an EU law that the UK has kept after Brexit, requires all fish and shellfish to be landed, even if they are unwanted (over-quota or below minimum size). It aims to promote more selective fishing methods, reduce bycatch, and improve recording of everything that is caught, not just what is wanted. Compliance with the LO is generally poor and actual levels of discards are difficult to quantify using the current fisheries observer programme.

In the UK, it is too early to tell how effective management is, as the Fisheries Act only came into force in January 2021. The Act requires the development of Fisheries Management Plans (FMPs) (replacing EU Multi-Annual Plans) but there are no details yet on how and when these will be developed. FMPs have the potential to be very important tools for managing UK fisheries, although data limitations may delay them for some stocks. MCS is keen to see FMPs for all commercially exploited stocks, especially where stocks are depleted, that include:
Targets for fishing pressure and biomass, and additional management when those targets are not being met
Timeframes for stock recovery
Technologies such as Remote Electronic Monitoring (REM) to support data collection and improve transparency and accountability
Consideration of wider environmental impacts of the fishery

Common octopus are fished throughout the year as a target species and bycatch. Although the majority of landings arise from offshore trawl fisheries, artisanal fisheries have high local economic and social importance in southern Europe. Small-scale coastal fisheries use pots and traps, as well as hand-jigs and trammel nets in depths between 20 and 200 m.

In the Northeast Atlantic, common octopus (O. vulgaris) is exploited by multiple nations and are predominantly caught off the Spanish and Portuguese coastline. In the more southern areas the main countries to exploit octopus, are Spain, Portugal and France, with 61% of reported catch by Portugal and 35% by Spain on average for the 2000 “2018 period. In Spain, O. vulgaris is caught by the artisanal and trawler fleets. In the Cantabrian Sea (Division 8c) and Galician waters (Subdivision 9a north), the artisanal fleet accounts for more than 98 “99% of O. vulgaris landings, mostly from traps. In Portuguese waters (Subdivision 9a C), a large percentage of O. vulgaris comes from the polyvalent (artisanal) fleet, using a range of gears which includes gillnets, trammel nets, traps, pots and hooks and lines. In the Gulf of Cadiz (Subdivision 9a S), historically the bottom-trawl fleet accounted for around 60% of the O. vulgaris catch on average and the remaining 40% was taken by the artisanal fleet using mainly clay pots and hand-jigs. However, the proportion of artisanal catches has increased; 77% in 2014 to 2016 and 84 “85% in 2017 and 2018.

Common octopus is a merobenthic species, found from the coast out to the outer edge of the continental shelf (200 m). Local density of O. vulgaris, as has been documented for other species of octopuses, is affected by the availability of solid material (rocks, stones, shells, anthropogenic litter, etc.) to be utilised for den construction.

Pots and traps are generally rigid structures into which fish or shellfish are guided or enticed through funnels that make entry easy but from which escape is difficult. There are many different styles and designs, in the Gulf of Cadiz fishers use clay pots for targeted octopus. Most pots and traps should have low environmental impact and seabed impact. Seabed impact from pots and traps is generally limited to light contact of traps and minimum penetration of the seabed from small anchors or weights. There may be some movement of the gear and ropes in poor weather but this will not have much effect on the seabed. In certain circumstances, there may be instances of ghost fishing of lost pots and traps. The clay pot fishery exclusively dedicated to catching common octopus in the Gulf of Cadiz, experiences reasonably high pot losses and breakages (up to 9,000 pots per month). Therefore, environmental impact may be somewhat significant dependant on the material of the pot used in these fisheries. One of the main causes of gear losses is the interaction of mobile gear with static gear.

By-catch from pots and traps is minimal and usually confined to small animals of the target species. This can be minimised by the use of appropriate mesh sizes in the cover netting and the use of escape gaps. Any by-catch in the pots can be easily removed from the trap and released back into the sea immediately without harm.

Predators of sub-adult and adult O. vulgaris include fish, marine mammals, birds, and other cephalopod species. Octopus vulgaris has been found in the stomachs of bottlenose dolphin (Tursiops truncatus), Risso s dolphin (Grampus griseus), and Mediterranean monk seal (Monachus monachus) in the Mediterranean Sea. Marine mammal predators of O. vulgaris in Galician waters include common dolphin (Delphinus delphis), long-finned pilot whale (Globicephala melas), and sperm whale (Physeter macrocephalus).