Inshore cod stocks strong in Shetland waters
Survey catches of cod in the inshore waters around Shetland last year were at their best for five years.
And the record squid catch rate observed in inshore waters in 2022 was surpassed, said scientists from UHI Shetland.
The results come from the 2023 Shetland Inshore Fish Survey (SIFS), an independent survey of commercial species.
The purpose of the survey, which has been carried out annually since 2011 using the 12m Atlantia II (LK 502), UHI Shetland’s own research vessel, is to provide independent information on the distribution, relative abundance and population structure of fish species in local waters. It is an important signal of the future health of key stocks.
Haddock was the main component of the survey catches, which are carried out in 52 pre-defined locations within 12 nautical miles of Shetland including in 25 areas of shallow water that are assessed as potential nursery grounds.
But cod was at its highest level since 2018, with the highest catches to the west of the islands.
And squid was even more prominent in 2023 than it was in 2022, with an average catch rate of 13kg per hour in shallow grounds compared to almost 11kg per hour the previous year.
Environmental change is the most likely explanation for the phenomenon, given that squid are relatively short-lived and breed only once.
Dr Shaun Fraser, Senior Fisheries Scientist at UHI Shetland, said: “The catch rate for cod on inshore grounds was the highest since 2018, and the average squid catch rate on shallow grounds surpassed even the record levels recorded during the previous year.
“We know from related work that larger-scale international fisheries surveys are not sensitive to these inshore trends, and so results like these clearly demonstrate the value and utility of the Atlantia II for maintaining an independent local survey capability.”
Shetland Fishermen’s Association Executive Officer Daniel Lawson said: “Given how important inshore waters are to the Shetland fisheries ecosystem, and how vital it is for the future of fishing that nursery grounds show healthy amounts and sizes of young fish, these are encouraging results, particularly for cod.
“These results also indicate a growing opportunity for Shetland’s inshore fleet to diversify into a targeted squid fishery, but fishermen need support and surety from government in order to make this a feasible and efficient prospect.
“The survey work carried out by UHI Shetland, with the Atlantia II absolutely vital for carrying it out, is critical to our evidence-based approach to fisheries, which contrasts starkly with many environmental NGOs which rely on misplaced ideology rather than data to advance their arguments.”