Fish flourishing in the Forth

14 July 2011

Despite its long history of industrial use the Forth Estuary is much healthier than many people realise, as proved by the range of fish species caught recently by scientists from Scotland's environment watchdog. 

The work, by the Scottish Environment Protection Agency (SEPA) was completed in the spring and will be repeated in the autumn. It was carried out to establish the health of our estuarine fish populations. Diversity and abundance of estuarine fish is a barometer of the health of the marine environment as they are mobile, relatively long lived and found near the top of the food chain. 

Myles O'Reilly, Senior Specialist Scientist in SEPA, said:

"The Forth Estuary with its extensive mudflats is relatively rich in fish species and acts as an important nursery ground for young marine fish. In Spring we undertook surveys of the fish that occur in the lower estuary close to the road and rail bridges and revealed 14 different species of fish. Trawling of the seabed between Port Edgar and Limekilns found the young stages of many commercial species such as Whiting, Cod, Dab, Plaice and Lemon Sole." 

Among the more colourful fish observed was a young Tub Ggurnard with beautiful blue-green pectoral fins, and scientists also caught a Sea Mouse, a marine worm found in the North Atlantic, the North Sea, the Baltic Sea and the Mediterranean.  SEPA aims to harm no fish during survey and the fish are returned to the water. Further surveys of the Forth are planned in the autumn.

Myles also explained:

"Traps set overnight for shore fish at Limekilns captured Flounder and Eelpout.  Eelpout are unusual among Scottish fish in giving birth to live young. They are cool water species and thought to be potentially sensitive to global warming.  We also use hand-operated siene nets in shallow bays to sample huge shoals of Sprat, important food for seabirds, such as Terns, nesting on nearby islands in the Firth of Forth."

Sampling involves the use of a variety of fishing methods, including seabed and mid water trawls from SEPA's survey vessel and, in the intertidal areas, using seine nets operated by hand or setting up Fyke nets to trap the fish overnight.

Ends

Notes to editors

Photographs to illustrate this story are available at http://www.mediafire.com/?vg1mhr1jnz5g8%20 external link (no subscription is required)

Photographs available:

•      Plaice and Flounder
•      Sea Mouse
•      Sea Scorpion
•      Tub Gurnard
•      Setting fish traps at Limekilns