Smelt Study

Juvenile smelt. Images used with permission from ZSL.

The European Smelt (Osmerus eperlanus) is a distant relative of the salmon; they are silvery green in appearance and usually reach around 20cm in length although they have been known to reach up to double this figure. Smelt live in the salty water of estuaries and river mouths and during May and August they travel up the river to spawn in freshwater before returning to the sea.

Smelt numbers were once high but a history of overfishing coupled with the fact that these fish are very sensitive to pollution has meant that numbers have dropped dramatically and the species is MCZ candidate species. Smelt have also been affected by man-made structures such as weirs, sea walls and flood defences which have reduced the smelt’s available habitat whilst making it difficult for them to reach their spawning grounds.

However, there are populations of Smelt in Scotland, Wales and England with some potential populations in the Wyre and Ribble estuaries. Our Smelt Monitoring Project aims to establish the presence and potential extent of the spawning Smelt population in these areas.

Little is known about the spawning behaviour of smelts but they are reported to spawn in early spring as water temperatures sustain 5-6°C; therefore, the Trust will monitor the water temperatures. Once identified, the Trust will commence monitoring at the estuary.

Surveys of the rivers’ shallows will be undertaken to determine their abundance and distribution; helping us to identify their preferred habitats. Our aim following this it to look at ways to potentially improve habitat and its connectivity to ease their migratory path in the hope of boosting the population of these rare fish.

A double fyke net used for smelt monitoring