Distribution and abundance ofLampetra planenpopulations in the Peene drainage (NE Germany) in relation to isolation and habitat conditions

Abstract

In the Ziemenbach, a third order stream of the Peene system, the habitats and density of brook lamprey (Lampetra planert) were investigated. A catalogue of habitat requirements for ammocoetes and adults was compiled. The abundance of brook lamprey was determined by counting adults on the spawning sites and systematic sieving of the ammocoetes. Human impact is probably the reason for strong changes in the population density during the investigated years. Habitats of lampreys in European streams are endangered by channelling and river maintenance. Together with other factors, this has led to the extinction of many populations. The occurrence of L. planen in the Peene drainage is now limited to 15 tributaries, although suitable habitats have been found in 36 streams, one third of the whole drainage system. To reduce the isolation of the populations and to enable the resettlement in other streams, up to 70 weirs with fish passes have to be construct.

Condition assessment of lamprey populations in the Yorkshire Ouse catchment, north‐east England, and the potential influence of physical migration barriers

“…For example, there was an almost complete absence of 1þ (2003 year class) ammocoetes in the River Ure, and comparatively small numbers of 0þ (2004 year class) ammocoetes in the rivers Derwent and Nidd. One issue influencing recruitment success of some lamprey populations in mainland Europe is physical barriers to migration, such as weirs and sluices (Waterstraat and Krappe, 1998;Oliveria et al, 2004), and it is possible that similar impacts periodically occur in the Yorkshire Ouse catchment. For example, very few river lamprey migrated upstream of Boroughbridge Weir in 2003(BEST, 2003, which was reflected in the current study by the small numbers of 1+ ammocoetes captured at Westwick and Bellflask.…”

Lampreys of the Iberian Peninsula: distribution, population status and conservation

“…Potter et al 1986, Waterstraat & Krappe 1998, shading (e.g. Hardisty 1944, Potter et al 1986, Waterstraat & Krappe 1998 and water temperature (e.g. Morman et al 1980) were also con sidered important in determining the distribution of the ammocoetes.…”

“…Other variables such as the organic content (e.g. Hardisty 1944, Potter et al 1986, Waterstraat & Krappe 1998, presence of macrophytes (e.g. Potter et al 1986, Waterstraat & Krappe 1998, shading (e.g.…”

“…Hardisty 1944, Potter et al 1986, Waterstraat & Krappe 1998, presence of macrophytes (e.g. Potter et al 1986, Waterstraat & Krappe 1998, shading (e.g. Hardisty 1944, Potter et al 1986, Waterstraat & Krappe 1998 and water temperature (e.g.…”

“…Typical spawning habitats for adults are generally found in upper river regions, in contrast with ammocoete habitats that are usually found more downstream (Waterstraat & Krappe 1998). Ammocoetes release pheromones (bile acids) into the water, which play an important role in attracting anadromous adult lampreys towards those rivers containing larvae.…”