麻豆淫院

Bottlenose dolphins have been dying from Morbillivirus at alarming rates in recent decades. Infected and sick animals suffer a combination of symptoms similar to pneumonia, encephalitis, and a damaged immune system.

Surprisingly, perhaps, for mammals who spend the majority of their time underwater, the virus is spread by airborne water droplets, which are then inhaled by other individuals, much as we might share a common cold by sneezing and sharing our infected expiration.

Synchronized breathing, when dolphins break the sea surface for air together, is a social trait seen especially in juvenile dolphins and, to a lesser frequency, in adult males. It likely helps to cement bonds, which, for the juveniles, may be useful in later life. This close proximity of synchronized breathing increases the risk of spreading and inhalation of water droplets containing the Morbillivirus.

The researchers sought to see whether synchronized breathing played a role in the spread of the virus among and between communities.

Contributing to the research with the United States' National Oceanic and Atmospheric Administration, Georgetown and Duke universities in the US is Bangor University's zoology lecturer Dr. Ewa Kryzyszczyk. The paper, "Breathing synchrony shapes respiratory disease risk in bottlenose dolphins" is in the journal of Communications Biology.

"Little was known about what factors caused the spread of the devastating Morbillivirus. Our findings suggest that synchronized breathing is one of the factors responsible for the spread within bottlenose dolphin populations. Their important social habits are contributing to the spread of the disease.

"Our findings could also help us to protect vulnerable populations. For example, one thing we know is that dolphins increase synchronized breathing when in the presence of boats, so reducing this stress when we know that the infection is present could help," says Kryzyszczyk.

A 'sentinel' species

Bottlenose dolphins are a "sentinel" species, that is, how they are faring acts as a signal for the health of the whole ecosystem. Dolphins are under increased pressure from human-introduced changes such as warming oceans and the introduction and spread of new diseases carried on plastics and other materials in the ocean. Incidences of Morbillivirus have led to mass deaths in populations around the globe, including more than 1,650 dolphins found along the US Atlantic coast over a two-year period. Populations were estimated to have diminished by more than 40%.

Modeling behavior based on observations and social mixing of two dolphin populations (the Potomac-Chesapeake Bay region of the US, where the dolphins are seasonal and migratory and share the larger area with other dolphin groups, and Shark Bay, Australia, where the dolphins are resident and do not migrate). The findings, borne out by stranded dolphin rates, showed that the most at-risk were the juvenile and adult male members of both communities.

Research also suggested that the infection rate was higher if a juvenile introduced the infection into the group. This is probably because juveniles synchronize their breathing most often鈥攎ore with their own age group鈥攖o create those bonds useful in later life. The spread of infection within the group is slightly less when introduced by adults. Least at risk of sharing were adult females and calves.

This research has important implications for predicting which individuals in a group are most at risk during epidemic outbreaks, especially useful in vulnerable species such as Guiana dolphins that are also at threat from Morbillivirus.