Holidaymaking Canberrans weren't the only ones diving for the ice blocks as the South Coast sweated through a 34-degree day.

Keepers at the Mogo Zoo brought out frozen fare for their charges; fruit mixtures for guys like the siamangs, from the gibbon family, and meaty treats for the carnivores.

Kinwah, the hand-raised tiger, cooled off in a wading pool with his turkey-meat-and-blood ice block, deflating a basketball on his teeth in the process.

And if Tunku the siamang ever gets tired of being one of Mogo Zoo's attractions she could try her paw as a wharfie down at the Batemans Bay marina.

A tinnie bearing fruit ice blocks was a welcome sight at the apes' island as the siamangs kept cool on Saturday - so much so Tunku helped bring it in and jumped on board.

Her 18-month-old baby brother, Batak, stuck close to their mother Fern who defied expectations to produce her youngest child in her early 30s. Fern's now 31 but the siamang life expectancy is into their mid-30s.

''She [Fern] is really amazing,'' animal operations manager Paul Whitehorn said. ''Generally everybody would have thought she was past reproduction by now, but then she pops out another one.'' Little Batak will certainly be her last.

Elsewhere mother and daughter Sumatran tigers Soreya and Senja cooled off by the pool and Snow's white lion cubs hung out in the shade of a tree.

Mr Whitehorn said the summer season had been a good one for the zoo. ''Every time they (people) come here there's something new, something different,'' he said.

''There's lion cubs, there's baby lemurs, there are plenty of youngsters around.''