Ecological knowledge base

Smelt - Osmerus eperlanus

Smelt - Osmerus eperlanus

General

Description Habitat

Occurrence

The Smelt is a species of fish in the Osmeridae family that lives in the waters of the Northern Hemisphere. A salt-water form, the anadrome smelt, is common in salt and fresh moving water. It grows in salt water and migrates inland to spawn. The freshwater form spends its entire life in fresh water, mainly the larger lakes #1. It swims in schools and prefers large open waters, such as lake IJssel.

Food habitat and strategy

Smelt larval feed on small plankton organisms. Juveniles feed on larger plankton. Adult smelts also feed on fish (smelts, small herrings and bass). The smelt itself is a major food source for many other fish and birds #1.

Growth and migration

Spawning takes place from March to June. The egg count per female can be as much as 40,000. They spawn on a substrate of sand, gravel, rocks or water plants. To prevent suffocation of the eggs the substrate must be rather solid #1.

Age and mortality

Salt water smelt may reach 30cm in length and can live for 8 years. The freshwater smelt, on the other hand, can live for 3 years and can only reach 14cm.

Response curves

Relations

Transparency(cm)	HSI
0	1
70	1
130	0.5
200	0.25
>200	0

Smelt prefer to swim in water with low visibility to remain hidden from predators. The better the visibility, the deeper the smelt will swim in the water column, or it will migrate to other areas. The assumed relation between visibility of the water and occurrence of smelt is: a visibility between 0 en 70cm, smelt is present, between 70 en 200cm unknown, no smelt with a visibility of over 2m. This dose-effect relation has been developed by expert judgement of IMARES.

Temperature	HSI
0	1
20	1
23	0.5
25	0
>25	0

There is no data available on the dose-effect relation of temperature and smelt. Two or three days with a temperature above 23°C will most likely lead to mass mortality. This dose-effect relation has been developed by expert judgement of IMARES.

Oxygen (mg/L)	HSI
0	0
2	0
4	0.25
6	0.5
8	1
>8	1

Also for oxygen, there is no data available on the dose-effect relation with smelt. An oxygen concentration higher than 8mg/l will most likely be preferred as this is the case for many other fish. The relation between oxygen concentration and the survival of smelt is however unknown. This dose-effect relationhas been set by expert judgement of IMARES.

Uncertainty and validation

The response curves have not been validated. Based on expert judgement, the relations were considered adequately enough to apply here.

Applicability

The response curves can be applied throughout the year as they contain a large range covering the entire year. Input data, measurement data or model data can therefore by consulted all year round.

Exemplary project

There is no exemplary project available.

Referenties

1 Sportvisserij Nederland, 2006.