He said there were stingrays right the way around the coast of New Zealand but Hawke's Bay had a significant quantity.
While the region had gravel beaches the sandy sea floor allowed stingray to feed off crustaceans and they stayed close to the sea floor, he said.
The stingray are found from Cape Kidnappers right the way to Bay View which is what brings the killer whales close into the shore.
Stingrays are also plentiful in rocky areas. All they need are sandy patches for their dwelling, he said.
The length of time whales choose to spend in areas depends on size of the pod as well as age of the whales and food supply.
"They could spend hours or a couple of days in a region."
Mr Yarrell said, like orca, humpback whales were transient types of whales.
He said they were a deep water species but did spend some time closer in shore, evidenced by previous strandings.
He said humpback whales liked to feed on squid and often travelled down south for bigger squid deep down in the sea.
But humpback whales weren't here for the rays on offer necessarily, he said. They often fuelled up before they set off travelling.
The aquarium manager said it was their inquisitive nature that often had them stopping off places like Hawke's Bay.
While it appeared more whales had swam into the Bay as of late, he said they were probably often there and people simply had not realised.
He said they often came with their young calves and people should keep out of their way.
There was generally always a dominant male with the pod, too, he said which could be seen from their dorsal fin being taller than other whales.
