Researchers have identified a core skin bacterial community that all humpback whales share across populations. Monitoring these bacteria could point to a way to assess the overall health of these endangered marine mammals.
Humpback whales are a species of baleen whale. The humpback has a distinctive body shape, with unusually long pectoral fins and a knobbly head. An acrobatic animal known for breaching and slapping the water with its tail and pectorals, it is popular with whale watchers off Australia, New Zealand, South America, Canada, and the U.S.
By studying the bacterial species on the skin of humpbacks, scientists think that they might be able to learn more about their health and the status of their environment. To explore this, scientists collected 56 skin samples from humpback whales from the North Atlantic, North Pacific and South Pacific oceans. The samples were obtained from biopsy collecting darts that bounce off the whales' skin and also from skin that naturally sloughs off when whales breach.
The analysis revealed that the overall composition of the bacteria differed by geographical location and metabolic state, as well as in stressed and deceased individuals. In stressed and deceased whales, researchers found less of the core bacteria and more potential pathogens present.
Thus by taking samples from whales, scientists think they will be able to predict the health of the whales and build up an ecological map.
The study was carried out by a team at the Woods Hole Oceanographic Institution, and the findings have been published in the journal PLOS ONE in a paper titled “Humpback Whale Populations Share a Core Skin Bacterial Community: Towards a Health Index for Marine Mammals?”.