Holeyfin, named for the hole in her dorsal fin, began visiting the beach in the 1970's. It is possible that she visited in the 1960's or was related to the dolphin Charlie (probably Charlene), who was first fed in the mid 1960's. Holeyfin became well known to the many visitors of Monkey Mia and was one of the first dolphins to provide researchers with fascinating information about bottlenose dolphin life.

One of the most remarkable discoveries happened in 1987, when an alliance of 3 male dolphins was herding Holeyfin. A rival alliance came to investigate, left, and soon returned with another alliance. With the numbers now in their favor, they attacked and captured Holeyfin. Clearly something special was happening at Monkey Mia. Not only do males form alliances, but they also form alliances of alliances, a pattern found only among humans and Shark Bay dolphins, but not our closest relatives, chimpanzees.

Holeyfin with sunburn scarring During this herding event, Holeyfin suffered severe sunburn (pictured left). Researchers strongly suspect she was chased up on to the beach by the three males (Sicklefin, Snubnose and Bibi) when she became stranded, receiving a severe sunburn. Holeyfin soon became pregnant with her son Koorda. However in 1989 both Koorda and Holly, her juvenile offspring, died in a pollution event (septic leakage). The three males, Sicklefin, Snubnose and Bibi also likely died from the pollution.

Seven years later Holeyfin again provided new insights into bottlenose dolphin ecology. On March 19, 1994, Holeyfin's 4-mo. old calf Hobbit was attacked and killed by a 5.5ft tiger shark. It was the first time a lethal shark attack had been witnessed despite 10 years of intensive research. Scientists realized that even relatively small sharks can kill dolphin calves. Although Holeyfin and others arrived at the scene too late to save Hobbit, she still successfully defended her carcass from the shark.

Holeyfin's calf, Hobbit, dies from a shark attack Holeyfin remained close to Hobbits carcass for hours, placing herself at possible risk from a shark attack. After a period of time, researcher Janet Mann pulled Hobbit's carcass for analysis. The calf was emaciated and in poor health prior to the attack. Analysis was used to determine the reasons for Hobbits poor health. Veterinarians at Murdoch University determined that Hobbit had bronchopneumonia, but were unsure if this was a symptom, rather than cause of her condition.Over the following two days Holeyfin returned to the site where Hobbit was attacked and whistled repeatedly.


The following year (1995) Holeyfin died from a stingray spine injury to her heart. Researchers Richard Connor and Mike Heithaus found her body and Janet Mann arranged to have her tooth layers analyzed by scientist Aleta Hohn (to determine her age-much like rings in a tree). The analysis revelead Holeyfin to be about 35 years old, making her the oldest known Shark Bay dolphin to date.

Holeyfin is mother to 'Nicky'. Nicky is currently the most regular visitor to Monkey Mia. Since females don't begin having calves until they are 12-15 years of age, the fact that Nicky was born in 1975 suggests that this was Holeyfin's first surviving offspring. Genetic studies underway by scientists Michael Kruetzen and Bill Sherwin from University of New South Wales, should help determine whether the Holeyfin and Crookedfin matrilines are related.

Click here to read about other Monkey Mia beach dolphins.