Not Just Bad Breath: Orcas Eject Unhealthy Mix of Bacteria When They Exhale, Possibly Due to Human Waste
So, orcas apparently have bad breath. It's okay, they can't help it; a new study published in the journal Scientific Reports revealed that the mix of bacteria the killer whale spews out is actually mostly the result of human contamination in their marine habitat.
According to a report from Phys Org, the study explored the role of infectious diseases on the decreasing population of the endangered Puget Sound orcas. The species have been endangered since 2005 with only 78 individuals now left in the wild. Some of the factors causing them problems are the lack of prey, pollution and disturbances from ships.
For the study, the team of researchers focused on killer whales in Washington state waters, collecting the droplets of waters that they exhale when they come to the surface. With samples collected over a four-year period, they were able to identify the array of bacteria and fungi in the orcas' breath.
Among the hodge-podge, healthy bacteria were observed. However, there were also a number of drug-resistant and potentially harmful ones such as salmonella and Staphylococcus aureus.
The scientists suggested that they are picking up the bacteria and fungi as they swim through urbanized waterways. Plenty of environmental stressors are present in these waters from human waste making its way from toilets to agricultural runoff.
Unfortunately, these could cause respiratory problems in orcas with weaker immune systems. Respiratory disease is a major concern with killer whales as scientists found over 40 percent of its population had some sort of infection in their lungs.
"These animals are subject to many stressors, which reduce the competence of their immune systems," co-author and marine mammal veterinarian Pete Schroeder explained.
However, it is still not certain if these microbes are definitely harmful to the giant orcas. Co-author Linda Rhodes pointed out that finding a potential pathogen in an animal doesn't necessarily mean it's sick.