Since the European sturgeon (Acipenser sturio) is one of the most highly endangered fish species worldwide with only one population known to still exist in the Gironde River, France, it is attempted to facilitate in-situ and ex-situ protection of the species through coordinated efforts within the former range.

We analysed ~310 records of river lampreys Lampetra fluviatilis (Linnaeus, 1758) (~19 977 663 specimens) and 54 records of sea lampreys Petromyzon marinus Linnaeus, 1758 (~86 specimens) for the southern parts of ICES Subdivisions 22 and 24 to 26 in the Baltic Sea covering the period 1649 to 2005. Most sea lamprey records came from Subdivisions 22 and 24. The majority of river lamprey records stem from Subdivisions 24 and 26. We found no distinct temporal trend for sea lamprey stock development. However, a long-term trend showing decreasing catches of river lamprey was detected, indicating a stock decrease of this species from 1887 to 1999. The largest numbers of lamprey (largely river lamprey but may include some sea lamprey as species were not distinguished in the past) were caught in the period 1890 to 1919. Approximately 82% of the total lamprey catch in our study area was made in Subdivision 26. Roughly 65.3% of the mean annual yield of lampreys came from the lower Vistula River, the Vistula Lagoon and the Bay of Gdań sk. The river lamprey was mainly distributed in estuarine and coastal marine areas. Offshore records of sea lamprey were also rare. From 1990 to 2005, most river lamprey records and recorded individuals originated from the Szczecin Lagoon and its adjacent waters, demonstrating the present importance of these waters for their spawning migrations. Of 9 known river lamprey spawning sites, 5 were found in the Peene River system which flows into the Szczecin Lagoon. At present, no sea lamprey reproduction site is known from rivers of the German Baltic Sea area. A rebuilding programme is required for the river lamprey; this should definitely contain measures to restore lost spawning sites and the connectivities within the river systems where spawning populations still occur. Protected areas in estuarine waters with important lamprey migration routes may be an additional measure for the conservation of these anadromous species.

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Summary The data of sturgeon catches in German and adjacent waters since 1980 have been collected from the major river systems and coastal waters in Germany and neighbouring countries. Over the past 10 years records on catches of exotic sturgeon species increasingly occur in the commercial and recreational fisheries, including the following species: Acipenser baerii, A. gueldenstaedtii as well as hybrids from different parental species such as H. huso x A. ruthenus, A. baerii x A. ruthenus. A total of 227 records are reported, including data on their distribution. Accidental or deliberate introductions of sturgeons have been mediated by aquaculture and/or petfish‐industries. Their occurrence is discussed in relation to plans for the re‐establishing of the native A. sturio.