Quintella, BernardoMateus, Catrarina S.Alexandre, Carlos M.Cardoso, Gabriela R.Belo, Ana F.Pereira, Esmeralda D.Telhado, AnaFerreira, JoãoQuadrado, FelisbinaAlmeida, Pedro R.2024-04-262024-04-262015-06-24https://hdl.handle.net/20.500.14394/25198<p>Presenting Author Bio: Graduates in 1999 in Marine Biology at the Faculty of Sciences of the University of Lisbon; Ph.D in the Biology and Conservation Area presented in 2007 at the University of Lisbon. At the present time is an Invited Assistant Professor at the University of Lisbon and develops its research among the MARE - Marine and Environmental Sciences Centre. The domain of specialization is ichthyology namely with the study of diadromous species. Present research dedicated to the study of fish migrations.</p>Abstract: Dams and weirs are known to have major impacts on migratory fish such as the sea lamprey Petromyzon marinus L., but these deleterious effects can be mitigated by the construction of efficient fishways. The Açude-Ponte dam at Coimbra represented the upstream limit of sea lamprey’s distribution in River Mondego until 2011, when a vertical-slot fishway was installed. Since then, several methodologies including visual counts and bio-telemetry techniques were used to monitor its efficiency. In 2014, a total of 221 adult lampreys were tagged with PIT tags to assess the efficiency of the fishway. During the 2015 spawning season, additional 200 lampreys will be tagged to assess the interannual variability of the fishway efficiency. From 28 lampreys tagged with conventional radio transmitters and released downstream of the weir, eight (ca. 30%) successfully negociated the fishway, reaching the upstream spawning areas in the main river stretch and tributaries. Data obtained from three lampreys tagged with EMG transmitters give a first glance of the fine-scale behavior and muscular effort required during fishway negotiation. Finally, visual counts identified the upstream passage of nearly 8,000 lampreys during the 2013 and 22,000 during 2014 spawning seasons. A statistical model developed with this data clearly shows that the weir discharges significantly influence the migratory behavior in the vicinity of the fishway, limiting its efficiency during high discharge periods.Aquaculture and FisheriesHydraulic Engineeringevent