I've caught a few and all fell off when out of water. Everyone I'm fishing with freaks like it's a snake but I grab it and put it back in the water as it's in it's last year of life. There like a wood tick but for fish.
I suggest people not to purposely kill lamprey as they do not cause permanent harm to fish (like sea lamprey). We have three lamprey species in Manitoba, Only Silver and Chestnut parasitize fish - and only in their short breeding cycle. Chestnut Lamprey are fairly rare, so it would be really unfortunate if they were killed.
Isaak- I've found they have responded without any "training" to a few different types in a variety of Mb waters - rivers and lakes. Commercial made boilies I use in Scopex - which is basically a toasted buttery-oil flavor / Bloodworm which is the flavor of Chironomid or Midge larvae which are crazy common in pretty much every lake/river and a favorite carp food/ Crayfish which is self explanatory and lastly Fruit Jello powder and Creamed Corn homemade boilies - cos Carp seem to love sweet stuff. The homemade stuff doesn't keep as well as the commercial stuff but is cheaper with a bit of added in labour . Hope that helps