An analysis of recruitment, exploitation and escapement targets.
Three trials were conducted to establish the exploitation rate of glass eel by a fishery on the River Severn that uses a traditional hand dip net method; between March 25th and April 8th; between April 22nd and May 13th and between May 4th and May 13th.
Juvenile eels (Anguilla Anguilla) were observed ascending the weir at Tewkesbury on the River Severn. A closer investigation of the movement of these juveniles revealed that the migration was largely unsuccessful due a number of obstacles.
There is evidence as early as 1850 of systems in place to control flooding and improve drainage on the River Severn.
Mark release recapture trials were conducted to determine the exploitation rate of glass eel by handheld dip nets in the Severn Estuary in the spring of 2020.
A simple trial at a tidal flap gate showed that glass eel passage was notpossible during the tidal phase of active glass eel migration.
A quantitative assessment of maximum swimming velocities of late season pigmented glass eels was undertaken to investigate the probability of glass
eels being able to undertake upstream migrations through flap/door type flood defence mechanism.
The proper management of a species within a national system of river basin districts requires validated data for the effectiveness of any fishery that could affect the recruitment.