Pros
Good Pay with benefits (medical, 401k w/ employer match) decent raises for the first couple years. Lots of time on the ocean seeing things not many people get to see. Great way to get your foot in the door for any budding biologist looking to get experience in the field. One of the better paying jobs for anyone with a BS in marine resource management straight out of college, plus they have pretty decent benefits.
Cons
The work is on call so you could get called at any moment to go to sea. Be ready to have to cancel your plans in order to go out to sea for days at a time. Long hours and long days out at sea, with not much contact to the rest of the world, can get lonely. You will have to be able to get up an all hours in order to sample the catch. Burn out is a real issue with this job, but it does get easier the longer you do it.