Cornish Sucker fish as bait

Found several of these in rock pools . I think they are what someone was trying to tell me are a very effective bait for pollack . Didn't have chance to try them so let them go .
Any thoughts ?
cheers
nick
Oh , also found some Goose Barnacles . Looked quite promising , not that you'd get them very often .

Sorry guys - I wouldn't know these things by name either if I hadn't just looked it up .
Sucker fish - find them in rock pools . About 3 - 4 " long , dark/reddish brown . Smooth skin . Taper down quite quickly from big head to thin tail . Can live out of water for several hours if just kept damp eg in seaweed ( you'll find them under dry rocks beside the pools too ).
On reflection I wouldn't kill them for bait anyway but it would be nice to know what the old boy was talking about .

Goose barnacles . Wierd prehistoric looking things . Like a stalk made up of white thumb-nails stuck together . Normally found offshore I think but occasionally washed up .