When surveying juvenile lampreys we use a stop net and back-pack electrofishing unit. We enclose three patches of habitat (1-5 sq-m) at each site, and fish for 1-3 mins per sq-m (or until no more lampreys emerge). This photo shows one sub-site, and we would look at three areas (sub-sites) like this over a 100m of river to make one site. At selected sites we undertake depeletion fishings but generally that find our catch efficiency is very high. Detailed habitat infomation is recorded at each sub-site, and RHS information is collected from along the 100m stretch.
For more information on lampreys please see our dedicated lamprey facebook page:-