Prikken in het Niersstroomgebied

Lampreys in the Niers tributary In the Niers tributary, a lowland river in the south of the Netherlands, populations of brook and river lamprey (Lampetra planeri and L. fluviatilis) were studied, focussing on distribution, spawning, habitat, densities and genetic viability. Lamprey larvae appeared to be present more wide spread than known hitherto. Suitable larvae habitat is present from the mouth of the river till more than 30 kilometres upstream. Densities of larvae are highest in the more downstream part. Compared to other known locations in the Netherlands, densities in the Niers are high (up to 8,8 larvae/m2). Spawning takes place in the Niers itself and several brooks in the tributary. We conclude there is a large and genetic viable population of river and brook lamprey present.