Scottish Shellfish Farm Production Survey 2020

This report is based on the returns of an annual survey questionnaire sent to all active authorised shellfish farming businesses in Scotland. Statistics on employment, production and value of shellfish from Scottish shellfish farms are presented.

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Production

The survey reports that the shellfish species cultivated in

Scottish waters in 2020 were:

Mussel:

Mytilus spp.

Pacific oyster:

Crassostrea gigas1

Native oyster:

Ostrea edulis

Queen scallop:

Aequipecten opercularis

Scallop:

Pecten maximus

Production was dominated by mussel and Pacific oyster, although small quantities of scallop, queen scallop (queen) and native oyster were also produced. The 2020 production data for each species by region are given in Table 1.

Table 1 - Scottish shellfish production by region, 2020.
Region Mussel Pacific oyster Native oyster Queen Scallop
(tonnes) (000s) (000s) (000s) (000s)
Table On-growing Table On-growing Table On-growing Table On-growing Table On-growing
Highland 527 93 1,633 1,113 1 0 0.5 0 19 0
Orkney 0 0 2 25 0 10 0 0 0 0
Shetland 4,427 3,310 75 0 40 0 0 0 0 0
Strathclyde 425 724 1,143 525 34 0 0 0 0 0
Western Isles 282 0 85 0 0 0 0 0 0 0
All Scotland 5,661 4,127 2,938 1,663 75 10 0.5 0 19 0
Weight (Tonnes) 5,661 4,127 235 6 >1 2

NB: This report lists regions with active shellfish farms operated by authorised aquaculture production businesses.

Conversion to weight used the following assumptions (based on industry figures): individual oysters averaged 80g; individual scallops averaged 120g; individual queens averaged 40g.

Table = sales directly for human consumption;

On-growing = sales to other businesses for on-growing.

[1] A proposed name change to Magallana gigas remains controversial (Bayne et al. 2007, Journal of Shellfish Research. 36, 545-547)

Table production by species is illustrated in Figure 1 (see page 4), while trends in production for the table market and on-growing in Scotland are presented in Table 2.

Table 2 - Trends in production data for the table and on-growing 2011-2020.
For the table 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 % change 19-20
Pacific oyster (000s) 3,136 2,706 1,891 3,392 2,693 3,534 5,034 4,031 4,393 2,938 -33
Native oyster (000s) 350 317 260 242 200 201 200 142 103 75 -27
Queen (000s) 27 9 33 18 33 155 273 18 18 0.5 -97
Scallop (000s) 78 58 40 48 30 35 47 31 26 19 -27
Mussel (tonnes) 6,996 6,277 6,757 7,683 7,270 7,732 8,232 6,874 6,699 5,661 -15
For on-growing 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 % change 19-20
Pacific oyster (000s) 1,400 3,190 6,216 6,792 5,864 4,584 3,849 4,240 2,405 1,663 -31
Native oyster (000s) 1 677 1,015 749 13 323 481 344 327 10 -97
Queen (000s) 0 0 1,490 500 900 17 300 0 0 0 0
Scallop (000s) 104 16 1,470 136 49 23 9 4 0 0 0
Mussel (tonnes) 282 309 1,281 1,263 1,841 2,619 4,437 2,137 3,493 4,127 18

Mussel production, for the table, decreased by 15% in 2020 (see figure 1) to 5,661 tonnes. The greatest regional contribution to mussel production was from Shetland, accounting for 4,427 tonnes or 78% of Scotland’s total. Pacific oyster production decreased by 33% from 2019. Highland region produced 56% of Scotland’s total farmed Pacific oysters in 2020. There was a very small amount of queen scallop production during 2020 as the main producer reported no production during 2020 due to the COVID-19 pandemic lockdown. The production of farmed scallops and native oysters both decreased by 27%. Historical data for all shellfish species show that production levels vary year on year. This can be due to a number of different factors such as poor spat fall, algal toxins, poor growth, adverse weather and fluctuations in market prices. During 2020, the biggest impact on shellfish production was the COVID-19 pandemic with a loss of much of the table trade to the hospitality sector during periods of lockdown and travel restrictions.

Figure 1 - Table production by species 2011-2020.

Prices of farmed shellfish fluctuated throughout the year. Their value at first sale was estimated from the following figures obtained from the shellfish farming industry. These vary with demand, level of production and geographical area of origin. The average price of Pacific oyster was £0.33 per shell; native oyster, £0.60 per shell; scallop, £2.32 per shell; queen scallop, £0.13 per shell and mussel £892 per tonne. The value of the table trade is estimated from the production figures shown in Table 1 (see page 2).

Mussel: £5.0 million

Pacific oyster: £0.97 million

Native oyster: £0.05 million

Scallop: £0.04 million

Queen: > £0.0001 million

In 2020, the total value at first sale for all species was calculated at approximately £6.1 million, a decrease of 23% from the £7.9 million estimated in 2019. This decline is largely due to impacts from the COVID-19 pandemic with many businesses reporting lost trade while the hospitality sector was in lockdown during much of 2020.

Contact

Email: lorna.munro@gov.scot

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