The Californian city of San Diego has been given 72 hours to remove harbour seals from a small beach area originally designated for children.
They were ordered by a judge to comply with an earlier order to clean up the Children’s Pool at La Jolla beach.
But lawyers for seal activists are planning to file a motion to block the move in what has been a decades-long battle over the issue.
The city plans to use the sound of barking dogs to scare off the seals.
They cannot use force because the seals are a federally-protected marine species.
“We can’t harm the seals in any way. Any method we use basically has to be benign,” said Andrew Jones, assistant attorney for civil litigation.
He said the city planned to pay someone to walk along the beach with a public address system broadcasting the sounds of dogs – backed up by two police officers in case of trouble.
“There’s certainly a lot of emotions revolving around this issue,” he was quoted by Associated Press as saying.
“We expect that this person could be harassed, even physically attacked”.
San Diego County Superior Court Judge Yuri Hoffman ruled on Monday that state law requires the beach be kept clean for children under a 1931 deed to the property.
He ordered the city to comply with a 2005 order by another judge to restore the beach to its original condition.
However, supporters of the seals would like the area to be preserved as a sanctuary.
“The seals need rest each day,” Dorota Valli, Seal Watch campaign coordinator, told AP.
“If they don’t get their rest, their health will be jeopardised and the local community will also suffer a huge economic cost. It’s an enormous tourist draw”.
The Children’s Pool – created by a sea wall built in 1931 through a gift by a La Jolla philanthropist – was donated to the city on condition it became a public area.
The seals began patronising the area in increasing numbers during the 1990s, AP reports.
Despite a city warning in 1997 not to use the pool because of high levels of bacteria from seal waste, people still continue to swim there.