The Atlantic States Marine Fisheries Commission has released a new report entitled: Proceedings of a Workshop on American Eel Passage Technologies.
The report summarizes the findings and recommendations of a July 2011 workshop that brought together over 120 biologists, engineers, and managers from around the world to explore the current state of eel passage at riverine migratory barriers.
The Workshop was funded by the Commission, Massachusetts Division of Marine Fisheries, and NOAA Northeast Regional Office’s Habitat Conservation Restoration Center.
The workshop and its report respond to recent concerns regarding a decline in recruitment of American eels and the need to restore this species to historic habitats by providing passage for both upstream migrant juveniles and downstream migrant adults at riverine barriers, including dams.
Upstream and downstream eel passage require unique technologies and considerations. Unfortunately, traditional upstream fish passage structures, such as fishways and fish lifts, are often ineffective in passing juvenile eels, requiring the development of specialized passage structures for this species.
Although designs for such passage structure options are available and diverse, many biologists, managers, and engineers are unfamiliar with eel pass design and operation, or unaware of the available options. Downstream eel passage is not as well understood as upstream passage and technologies need to be developed and evaluated.
The workshop provided a forum for eel passage experts to share and discuss successful and unsuccessful passage technologies and evaluations from different parts of the world.
General guidelines on the design and operation of upstream eel passage structures are covered in the report and examples with specifications are provided for a variety of budgets and barrier types. Current technologies and experiences with downstream passage were also discussed at the workshop and are highlighted in the report. Research needs and questions identified during the workshop are included to guide next steps in improving both upstream and downstream American eel passage.
Proceedings of a Workshop on American Eel Passage Technologies can be found at:
source: Atlantic States Marine Fisheries Commission