I just wanted to clear this up in the interest of refining our knowledge of knitting terms and techniques.
Yes, Fisherman's Wool does indeed come from fisherman. Sheep have nothing to do with it (unless the fisher folk have some really wild parties when they're ashore, which is a whole different subject - not covered here - but may explain where the lanolin content comes from!)
First off, there are fishermen all over the world, some in warm climates and some in cold. This effects the thickness, quality and color of their "wool" as well as the difficulty in shearing the fishermen. Those who live in the colder climates strongly resist this process since frostbite is a distinct possibility.
In those locales it's not unusual for teams of shearers to lie in wait at the docks when the fishing boats come in and pounce on unsuspecting fishermen, shearing them hairless before they can raise an alarm. It is rumored that a good 4-man shearing team can clip a dozen fishermen in less than 15 minutes. Personally I think that's just an urban legend put about by those living near the docks to frighten their children into staying safely indoors after dark.
Those fishermen living in warm climates tend to produce a softer, silkier and lighter-colored "wool", mostly on their chests and in a few unfortunate cases, their backs. They are far easier to shear since they are so much more comfortable without so many follicles in the heat and humidity. In these locales, the truly professional shearing teams make sure that the shear-ees have a good layer of SPF 40 sun block on after the clipping.
All in all, it's truly an arduous task regardless of which climate you're working in. Keep that in mind the next time you buy a skein of Fisherman's Wool or enjoy the wonderful garments made from it.
I hope this helps fill in any gaps you all might have had in your understanding of this subject! And many thanks to all those wool-less fisherman world-wide who contribute so much to our knitting culture!
Happy knitting everyone!