Outdoors: Fish Spawning in the cree

As one of our rarest fish prepares to spawn, so conservationists get ready to offer a helping hand

It smells of cucumber and is one of Scotland’s most endangered fish, and at this time of year makes a remarkable migration into the lower reaches of the River Cree in Galloway to spawn. The annual spawning influx of sparling, or smelt as they are also known, is an incredibly brief affair, with the fish moving into the lower reaches of the river in their thousands for only a couple of hours during the darkness of a few March nights, before quickly withdrawing back to their coastal feeding grounds in the sea again.

For Liz Etheridge of the Galloway Fisheries Trust (GFT) it is a tremendously exciting moment and one that is always hard to accurately pinpoint. The trigger for the spawning migration is related to a combination of high spring tides and the right temperature, and for the last two years Liz and a dedicated team of helpers have tried to anticipate the exact moment when the sparling will arrive so that they can catch some of the fish and collect their eggs as part of a conservation project to help ensure the survival of this threatened species.

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Sparling were formerly recorded from 15 sites in Scotland but now only occur in three known locations – the Cree, the Tay and the Forth. No-one knows for sure why the sparling should have undergone such a startling decline, but the reasons are most likely to include over-fishing, pollution and the construction of weirs and other obstructions that provide barriers to migration.

The Cree now has the only known population on the west coast of Scotland, and although spawning numbers are believed to be relatively healthy, the fish are vulnerable to extinction should some localised catastrophe occur during the short breeding cycle. For this reason the GFT is engaged in a project to translocate sparling eggs to another river in the region where the fish previously occurred, the Water of Fleet, so as to establish a new breeding population.

Etheridge explains: “The Scottish rivers that flow into the Solway Firth used to hold quite a few populations of sparling but these have all disappeared apart from this last remaining spawning site in the Cree and this is why we feel it is so important to provide a helping hand and establish a new population that will help safeguard the future of this wonderful fish on the Scottish west coast.”

It can be a hit and miss affair predicting the exact few nights that the sparlings will surge into the Cree. But for the last two years GFT biologists using torches and hand-nets have successfully been able to catch some of the fish as they swirl in a spawning frenzy in the shallows of the river.

Etheridge says: “The whole event is very exciting and the sparling are so intent on spawning that they don’t seem to take much notice of us as we wade in amongst them.”

The caught sparlings are then transported to the Water of Fleet where the females are stripped of their eggs, which are then fertilised with the milt from multiple males. Each female can hold anywhere between 40,000 and 100,000 eggs. It is hoped that the first mature sparling will return to the Water of Fleet either this year or next to spawn.

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Sparlings were once widely eaten and have a lovely cucumber aroma when first caught. They are normally quite small fish, the slim and slightly translucent body growing up to about 20cm. Indeed, the Scottish name sparling derives from an old French word meaning “small fish” – but those in the Cree tend to be much bigger and can grow as large as 28cm, making them genetically unique.

It is still too early to tell how successful the translocation project has been, but Etheridge is in no doubt about the importance of protecting one of Scotland’s rarest and most unusual types of fish.

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“Sparling form an integral part of our biodiversity and are an important source of food for a number of aquatic birds and mammals,” she says. “The Cree population is very vulnerable because all the fish come into the river in a concentrated focus over a very short period of time and it could only take one unexpected pollution incident to wipe out the entire population, which would be a tragedy.”

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