Study

Corner and sloped culvert baffles improve the upstream passage of adult European eels (Anguilla anguilla)

  • Published source details Newbold L.R., Karageorgopoulos P. & Kemp P.S. (2014) Corner and sloped culvert baffles improve the upstream passage of adult European eels (Anguilla anguilla). Ecological Engineering, 73, 752-759.

Actions

This study is summarised as evidence for the following.

Action Category

Modify design of culverts

Action Link
Eel Conservation in Inland Habitats
  1. Modify design of culverts

    A controlled study in 2011 in an outdoor experimental channel in Southampton, UK (Newbold et al. 2014) found that a yellow European eel Anguilla anguilla travelled upstream more frequently through a culvert with corner or sloped baffles than an unmodified culvert. A yellow eel travelled upstream a greater number of times through a culvert with corner baffles (21 of 25 eels, 84%) or sloped baffles (21 of 25 eels, 84%) than through an unmodified culvert (7 of 25 eels, 28%). In July–August 2011, a single wild-caught yellow eel was released 3 m downstream of a culvert (1.2 m diameter, 6 m long) in an experimental channel during each of 25 x 1-h night-time trials with three culvert designs (corner, sloped or no baffles). Five corner baffles (0.15 m high, 0.87 m wide) constructed of 10-mm plywood were installed 1 m apart along one wall of the culvert. Sloped baffles were created by adding a sloping polycarbonate twin-wall sheet (0.4 m long, 20° angle) to each corner baffle. Water discharge in the channel was 66 l/s. Eel movements were filmed using overhead cameras with infrared lights. 

    (Summarised by: Anna Berthinussen)

Output references
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