Findings of the new study reveal potential factors that affect the deaths of the many orcas for the last decades. An array of bacteria and fungi are sprayed by orcas as they break to the surface of the water to exhale.
According to Mail Online, in the study published in the journal of Scientific Reports said that orcas' breath samples show a presence of many microorganisms that is capable of causing a disease. It is also found that due to human wastes contamination in the marine environment, some of the microbes from orcas' breath were resistant to multiple antibiotics used by humans and animals.
Scientists have waited and followed orcas in the waters in Washington to collect breath samples as they emerge on the surface of the water. By swinging a pole about 25-feet long with several Petri dishes above the orca's blow hole, scientists collected the droplets that are sprayed out from the animal during exhalation process.
The study takes around four years to complete using unique breath samples. An array of bacteria including drug-resistant salmonella and Staphylococcus aureus as well as fungi were gathered from the orcas' breath samples. This find makes the scientists worried.
As per ASZ News, the struggling population of the endangered Puget Sound orcas has declined to 78 based on the recent studies. The decline of the population of orcas in decades is due to threats from lack of prey, pollution, and noise disturbance from vessels.
A great percentage of Orcas' diet are the Chinook salmons. But since 1980's Chinook's population were cut-down in half, some killer whales died from starvation while others died in trauma from boat run-ins and diseases.
However, according to British Colombia Ministry of Agriculture, Animal Health Center in Abottsford veterinary pathologist Stephen Raverty, the death of orcas may also be due to bacterial infestation and infection. Orcas are harboring and absorbing the bacteria in their habitat from manmade pollution in the marine environment. "They are recruiting the bacteria in their habitats," Raverty added.
Orcas which swim through urbanized water ways encounter a lot of stressors caused by humans. These stressors include everything from the flush down toilets to agricultural run-offs. Those with weak immune responses can be more susceptible to bacteria resulting in respiratory disease.
Pete Schroeder, marine veterinarian and the author of the study, said that "these animals are subject to many stressors which reduce the competence of their immune system." Schroeder study aimed to provide a better look on the pathogens that affects the endangered orca population and to develop a comparison with the changes of the whales' respiratory conditions.
Because orcas break through the surface of the water to gasp and exhale for air, they are very prone to the take in contaminants and other microbes from the water surface. But scientists do not know enough to say how harmful the microbes to the orcas.
40 percent of the deaths had some respiratory infection. "Bacteria is there, and if for any reasons the animal got immune suppressed, it could provide an opening to make orcas sick," Raverty said.
Scientists are still working on creating personal health records for each endangered orca which are intensely tracked ad photographed. The Puget Sound orcas are identified by the unique black and white markings.