Bottom rung worker, often times in construction trades including skate park construction, boat building, and home construction among others. Usually used in a negative fashion to insult ones lack of care, craftsmanship, and/or dependability on the job. Name is derived from boat hands working to grind fish parts used to attract sharks and other game fish.
"I got about four chum monkeys on my crew that put more nails in the dirt than in the wood."
"Tell that chum monkey over there that if he quits scratching his head and his ass at the same time that his hammer will work better!"