Dugongs and manatees are the worlds only fully herbivorous marine mammals, with similar ecological roles and welfare challenges despite being found on different continents.
Both dugongs and manatees face the welfare challenge of sharing busy waterways with boats and fishing operations. Their slow surface-surfacing behavior and tendency to congregate in warm water refuges creates regular conflict with watercraft. Entanglement in crab trap lines, fishing nets, and marine debris causes drowning and injury. Cold stress in manatees that cannot access warm water winter refuges causes hypothermia and death. Both species carry the marks of boat strikes — scarring patterns that serve as individual identification marks but represent histories of painful injury.