Dolphin behaviour investigated

As a marine biologist and PhD student Kate Sprogis witnesses the weird and wonderful behaviour of the South West’s dolphin population, including seeing how the intelligent mammals feed.

Ms Sprogis carries out dolphin surveys in an area reaching from Binningup to Busselton and includes the Leschenault Inlet and Collie River for the Murdoch Cetacean Research Unit.

A year and a half into her doctorate, Mrs Sprogis has recorded big groups of dolphins herding schools of fish such as whiting.

‘‘We have also seen a number of dolphins toss octopuses out of the water and into the air to make sure they are dead before they eat them,’’ she said.

‘‘We think this is so the octopus’s suckers don’t attach onto them.’’

Ms Sprogis’ project will use longterm data to investigate the abundance, population dynamics, social structure and habitat use of Bunbury’s bottlenose dolphins.

‘‘In the winter time many of the adult female dolphins and their calves congregate in the inlet where the salt water mixes with the fresh water from the river,’’ she said.

‘‘The dolphins are commonly foraging in this area and we recently found an adult female dolphin, Tipex, repeatedly whacking a cobbler fish on the water’s surface.’’