Female southern Australian dolphins like to raise their young within the sisterhood as they hope strength in numbers boosts their babies’ chances of survival, according to researchers from Flinders University in South Australia.
The latest findings show female bottlenose dolphins also group in similar reproductive condition with the research indicating it could help them find food along with male dolphins and fend off sharks.
Flinders University marine biologist Dr Fernando Diaz-Aguirre, the lead author of the study, said researchers made 152 boat surveys over two years at Coffin Bay on the Eyre Peninsula, a popular holiday destination in the northwest of South Australia.
The researchers from Cetacean Ecology, Behaviour and Evolution Lab at Flinders University, saw 967 dolphin groups in Coffin Bay and based their findings on more than 11 sightings of 55 females.
They found female dolphins liked to stay close to other females in similar reproductive condition and it was likely their babies fared best by having their mothers forming these bonds.
They also found bottlenose dolphins then raise their calves in select female groups in local bays while maintaining loose social bonds with male dolphins.
“These close social groups among related females appear to be vital for them while raising young calves, or for those without calves who also combine due to similar biological requirements related to feeding and mating,” Dr Diaz-Aguirre said.
“As well as key pointers on social evolution and behaviour in these highly complex marine mammals, our study also provides important information for the conservation of the Coffin Bay population.”
The study, published in Scientific Reports, sheds new light on how dolphin societies are developed and maintained including special adaptations such as hunting skills and how social learning is passed on between generations.
Flinders Associate Professor Luciana Moller, the senior author of the paper, said these studies were important in understanding the evolution of animal societies.
Success in female reproduction in mammals is limited by lactation, gestation and caring for the young with ecological factors affecting the amount of food they can obtain and predation risk affecting the chances of their babies surviving.
“(This work is important) for providing information to conservation managers to secure the future survival of these unique dolphin populations,” Associate Professor Moller said.
“Small resident populations of dolphins, as the one in Coffin Bay, are particularly vulnerable to changes in the environment and represent sentinels of the health of coastal ecosystems.”Jump to next article