" Mortality rates among the crews of vessels employed in the African slave trade were comparable to those of the slaves themselves. It was not unusual for 40 percent of the crew to perish during a single voyage, most from tropical diseases against which they had no resistance. About half the sailors pressed into the Royal Navy died at sea. "

― Colin Woodard , The Republic of Pirates: Being the True and Surprising Story of the Caribbean Pirates and the Man Who Brought Them Down