Two grey whales spotted swimming in California river

A marine biologist says 'they look like they’re having a good time so maybe they’re not eager to leave'

Two grey whales were spotted swimming in the shallow waters of the San Gabriel River channel in southern California, prompting only mild concern and several onlookers.

Lifeguards watched the pair of 22 to 25-foot long whales closely and experts from a marine mammal centre told the local television station the animals did not appear to be stuck in the channel separating Seal Beach and Long Beach.

Seal Beach lifeguard Chief Joe Bailey said "they are doing one of two things ... scratching barnacles off themselves or feeding”.

"We don’t want to put pressure on them. They are doing what whales are gonna do, which is eating and swimming around,” Mr Bailey said.

The pair were first seen around 10 am local time and by 4 pm, one of the whales had made their way back into the ocean. The other has continued to stay swimming around the river bed. Neither are calves nor are they fully grown. Grey whales can reach up to 50 feet long.

Biologist Justin Greenman of the National Oceanic and Atmospheric Association told the Ocean County Register newspaper that the whales appeared “tactile,” adding that “they look like they’re having a good time so maybe they’re not eager to leave”.

While it may be unusual to see whales in such shallow waters close to the shore, Mr Greenman said it is not unheard of given migratory patterns leading animals back north with their calves along the southern California coast.

“What we’d [be] concerned about is if they were like caged tigers, going back and forth,” Mr Greenman said, but the animals appeared to be “healthy”.

Officials may have to block the remaining whale from swimming further inland in the river, but for now they are just waiting to see if it joins its companion back in the ocean