Crab and lobster fisheries - stock assessments: results 2016 to 2019

1. Introduction

1.1. Overview of Scotland’s Crab and Lobster Fisheries

Crabs and lobsters are important species for the Scottish fishing industry. Although the total weight landed is small relative to finfish landings, crab and lobster attain high prices. In 2020, the combined crab and lobster species landings of approximately 9,000 tonnes had a value at first-sale of over £31M (Scottish Sea Fisheries Statistics, 2021). The fishery is long established and was traditionally an inshore mixed species creel fishery, prosecuted by small vessels. However, improved technology and the ability to store and transport live animals in the 1980s led to the development of an offshore fishery for brown crab. This, and the demand from new markets, resulted in a substantial increase in the Scottish landings.

Creel fishing in Scotland continues today as an inshore fishery around most of the Scottish coast, with vessels setting their gear within a few miles of the shore. The fishery is typically a mixed species fishery with both crab and lobster being targeted, albeit with some seasonal and regional variation. Most creel vessels are small, less than 10 m in length and with only one or two crew, and make short day trips to haul creels. However, a number of larger vessels take part in an offshore fishery to the north and west of Scotland. These vessels, which are up to 25 m in length and have a crew of four or five, mainly target brown crab and carry vivier ponds on board to keep the catch alive. The size and power of these vessels enables fishing on offshore grounds such as the Papa and Sule Banks, with boats landing catch into ports such as Scrabster on a weekly basis. These ‘vivier vessels’ or ‘super-crabbers’ are fewer in number than the small day vessels, but their catches represent over 50% of brown crab landings in some regions. Local processors were the preferred market until the overseas market emerged in the 1990s. By this time, technology had developed to enable the transport of live animals by vivier lorries (specially adapted vehicles containing cooled ponds for the transport of live shellfish), within a day of landing. It is common for crabs and lobsters fished in UK waters to be transported live to the continent, particularly France, Spain and Portugal, where there is a good market. After Brexit, despite changes in trading arrangements, the majority of crabs and lobsters are still exported to the European Union, with the region accounting for 84% of total UK exports. More recently, brown crab have also been exported to emergent Asian markets including China, where “dry transport” of live animals is the preferred method. Exports of crab and lobster from the UK to China rose steadily in the period 2017-2019, from around £18M in 2017 to £31M in 2019. However, since 2019 exports to China have reduced sharply, with only £7M exported in 2020.

The most important crab species, in terms of weight and value, landed in Scotland is the edible or brown crab (Cancer pagurus) which is found all around the Scottish coast. The second most important by landed weight is the velvet swimmer crab (Necora puber). Velvet crabs are often caught in the inshore creel fishery with lobster and brown crab and were once considered to be a ‘pest’ species. Very few fishermen fish solely for velvet crab, although some target the species at certain times of the year. The Scottish fishery expanded in the early 1980s following the collapse of the Spanish fishery (MacMullen, 1983), to become the largest in Europe (Tallack, 2002). Other crabs landed include deep-water crabs (Chaceon sp.), the northern stone crab (Lithodes maja) and the shore or green crab (Carcinus maenas), but these species only comprise a small proportion of the total landings (Table 1).

European lobster (Homarus gammarus) is a valuable species for which seasonal prices can be as high as £20 per kg at first sale. Other lobsters landed include the spiny lobster or crawfish (Palinurus elephas), squat lobsters (family: Galatheidae) and the Norway lobster (Nephrops norvegicus), also known as langoustine or Nephrops. In Scottish waters P. elephas is caught mainly on the west coast and along the north coast to Orkney and Shetland. Landings of P. elephas into Scotland up to 1998 were consistently over 30 tonnes dropping to an average of around 5 tonnes over the last 10 years. The Nephrops fishery is one of the most economically important Scottish fisheries with vessels targeting this species operating mostly trawl gears, although a smaller scale Nephrops creel fishery also takes place in the west coast of Scotland. Nephrops stocks are assessed by ICES (International Council for the Exploration of the Sea) working groups and managed under a Total Allowable Catch (TAC) system. They are therefore not considered further in this report.

1.2. Management and Regulations

In Scotland, vessels fishing for brown crab, velvet crab, spider crab, green crab, lobster or crawfish must have a licence with a shellfish entitlement. The quantities that are permitted to be landed are not restricted. Owners of vessels of length up to 10 m with a shellfish entitlement are required to complete the FISH1 form for all landings of lobsters and crabs and submit it on a weekly basis to the Fishery Office at which the vessel is administered. In July 2016, the Scottish Government introduced a number of changes to reporting on the FISH1 form as part of vessel licensing requirements. Since then, fishermen have been required to report (1) the position where fishing activity starts on any fishing day (for creel vessels this corresponds to the first position where creels are hauled); and (2) the number of creels hauled associated with the declared landings quantity. For vessels between 10 m and 12 m, data on fishing activity by trip must be recorded in a paper logbook and submitted to the Fishery Office within 48 hours of landing. Vessels over 12 m must use electronic logbook systems to record their activity. Licensed fishing vessels, which do not hold a shellfish entitlement, are allowed to land a maximum of 5 lobsters and 25 crabs per day. Regulations effective from April 2017, restrict the numbers of certain shellfish species that can be taken by unlicensed fishing boats on a daily basis. The restrictions are set daily per vessel as: 1 lobster, 5 crabs (any combination of the following species: brown crab, velvet crab, green crab and spider crab), 10 Nephrops and 6 scallops (The Shellfish (Restrictions on Taking by Unlicensed Fishing Boats) (Scotland) Order, 2017).

There is currently a restrictive licensing system, whereby no new licenses or entitlements are being granted. There are, however, non-active (latent) licence entitlements, which mean that there is the potential for the number of vessels actively fishing for crab and lobster to increase. In 2014, participants in the European project ACRUNET (A Transnational Approach to Competitiveness and Innovation in the Brown Crab Industry) produced an analysis of latent capacity and the implications for the management of the brown crab fisheries. It became clear that in the UK and Ireland there is significant latent capacity (part of the fleet that is currently inactive but continues to hold fishing entitlements) that could potentially target brown crab, but the likelihood of currently unused shellfish entitlements becoming active could not be estimated at the time (Mesquita et al., 2015).

Crab and lobster fisheries are not subject to international TAC regulations or national quotas although there are measures to restrict fishing effort in the west of Scotland. After Brexit, the maximum annual fishing effort for UK vessels over 15 m participating in the brown crab fishery was maintained at the level set by previous EU Regulations (702,292 KW days in ICES Areas 5 and 6 and 543,946 KW days in ICES Area 7 (EC, 2004; MMO, 2022).

MLS regulations designed to protect juvenile animals apply to the main commercial crab and lobster species. These are summarised in Table 2. In 2017, Marine Scotland introduced a number of new management measures. These include: increases in MLS in some areas (Table 2), the prohibition of landing berried velvet crab and a decrease in the maximum landing size of female lobster (from 155 mm to 145 mm CL, except Orkney and Shetland) (The Specified Crustaceans Order, 2017). Other extant regulations in the crab and lobster fishery are described in detail in previous assessment reports (Mesquita et al., 2011; Mesquita et al., 2017; Mill et al., 2009).

This report presents summaries of historical and recent landings data and the results of stock assessments for brown crab, velvet crab and lobster, updated with data collected between 2016 and 2019. A description of the biology, habitat and life history of these species is provided in Mill et al. (2009).