EVIDENCE FOR NATURAL REPRODUCTION OF ATLA NTIC SALMON (SALMO-SALAR L)IN A FRENCH TRIBUTARY OF THE RHINE BASED ON GENETIC-ANALYSIS OF EGGS COLLECTED FROM REDDS

By means of the polymerase chain reaction, we were able to amplify spe cific regions of the nuclear (conserved region of the 5S rRNA genes) a nd mitochondrial DNA (ND-5/6 segment) extracted from eggs that had bee n collected from four salmonid redds in a tributary of the Rhine. Thre e redds were identified as Atlantic salmon redds and one as brown trou t redd. These results show that molecular methods allow an identificat ion of salmonid species at very early stages of development, and that the re-introduction programmes of Atlantic salmon in the Rhine basin r esulted in a re-establishment of natural reproduction of Atlantic salm on in the French part of this basin.