Bottlenose homes need help
Adelaide’s bottlenose dolphin habitats need more protection, Flinders University researchers say.
A new paper has delved further into the distribution and behaviour of local bottlenose dolphins, providing valuable new conservation guidelines to inform future management.
A long-term conservation plan for the 100-200 bottlenose dolphins who return to live in Adelaide’s coastal waters each year would need support from the community - in particular boaties, fishers and tour operators, says School of Biological Sciences researcher Nikki Zanardo.
Groups of dolphins reside in the Port River and further south of the Noarlunga Reef, while researchers have also observed that the dolphins using the main metro coastline favour shallow near-shore areas and temperate reefs in summer, shallow near-shore areas in autumn and the deep waters further offshore in winter.
“To support these coastal marine mammals, and aid their future survival, there needs to be more signage and management of these critical habitats as priority conservation areas,” says Ms Zanardo.
“Increased human activities, in fishing, boating and coastal zone developments is putting ever more pressure on these dolphins which seasonally inhabit the near-shore metropolitan areas.
“Pressure on fish stocks, too, will influence the prey available to dolphins in these core feeding areas.”
Along with pressure on feedstock, interaction with humans emerged as another pressure on the urban dolphin habitat.
“It is especially important that we continue to monitor dolphin numbers and changes in their habitats to ensure not only the long-term presence of this urban dolphin population but also the overall health of Adelaide’s coastal environments,” says Associate Professor Luciana Möller.
Current management strategies for dolphins along the Adelaide metropolitan coast are limited to vessel and swimmer approach distances.
Dr Guido J Parra says the studies were useful to identify important areas for the conservation of southern Australian bottlenose dolphins along Adelaide’s metropolitan coast.
“What’s more, the methods we used in this study can be applied to other marine species, and help identify important habitats and the potential ecological function they provide to these species,” he said.
The study has been published in Marine Ecology Progress: “Ensemble modelling of southern Australian bottlenose dolphin Tursiops sp. Distribution reveals important habitats and their potential ecological function”.