A Lima zoo is racing to save dozens of seabirds, including protected penguins, after 6,000 barrels of crude oil spilled off Peru's coast due to waves from a volcanic eruption in the South Pacific.

More than 40 birds, including Humboldt penguins -- listed as vulnerable by the International Union for Conservation of Nature -- were brought to the Parque de Las Leyendas zoo after being rescued from polluted beaches and nature reserves.

"We have never seen anything like this in the history of Peru," biologist Liseth Bermudez told AFP, while tending to a bird.

A cormorant is among dozens of oil-tainted birds being treated at a Lima zoo A cormorant is among dozens of oil-tainted birds being treated at a Lima zoo Photo: Parque de las Leyenzas Zoo via AFP

"We didn't think it was going to be of this magnitude."

A team of veterinarians is caring for the birds, bathing them with special detergents to remove the suffocating oil.

The animals have also been given anti-fungal and anti-bacterial drugs, as well as vitamins.

The birds are bathed with special detergents to remove the suffocating oil, and given food, medicine and vitamins The birds are bathed with special detergents to remove the suffocating oil, and given food, medicine and vitamins Photo: Parque de las Leyenzas Zoo via AFP

"The birds' prognosis is unclear," Bermudez said. "We are doing everything we can."

Peru has declared an environmental emergency after almost 264,000 gallons (1.2 million liters) of crude oil spilled into the sea last Saturday when a tanker was hit by big waves while offloading at a refinery.

The abnormally large waves were triggered by the eruption of an undersea volcano near the archipelago of Tonga, thousands of miles (kilometers) away.

Peru has declared an environmental emergency after almost a million liters (264,000 gallons) of crude spilled into the sea when a tanker was hit by waves while offloading at a refinery Peru has declared an environmental emergency after almost a million liters (264,000 gallons) of crude spilled into the sea when a tanker was hit by waves while offloading at a refinery Photo: Parque de las Leyenzas Zoo via AFP

The spill near Lima has fouled beaches and harmed the fishing and tourism industries, with crews working non-stop to clean up the mess.

The environment ministry said Sunday that more than 180 hectares -- equivalent to around 270 soccer fields -- of beach and 713 hectares of sea were affected, as sea currents spread the spilled oil along the coast.

The health ministry has warned would-be bathers to stay away from at least 21 affected beaches.

Map with details and showing impacted zones Map with details and showing impacted zones Photo: AFP / Tatiana MAGARINOS

Biologist Guillermo Ramos of Peru's Serfor forestry service said more animals will die if the oil spreads.

"There are species here that feed on crustaceans and fish that are already contaminated," he said.

Serfor staff have found many dead birds and sea otters on beaches and in natural reserves since the spill, he added.

More than 150 bird species in Peru depend on the sea for nutrition and reproduction.

Among the birds rescued alive but in need of help are different types of cormorants and six Humboldt penguins.

Juan Carlos Riveros, scientific director of rescue NGO Oceana Peru, said the oil could affect the reproductive capacity of some animals and cause birth defects, especially in birds, fish and turtles.

The government has sought compensation from Spanish oil company Repsol, which owns the tanker.

But the company denies responsibility, saying maritime authorities had issued no warning of abnormal waves after the Tonga eruption.

On Sunday, Jaime Fernandez-Cuesta, president of Repsol in Peru, said the Spanish company was doing everything it could to mitigate the environmental damage.

"We are doing everything possible, without sparing any expense, to remedy this entire disaster as soon as possible," Fernandez-Cuesta told the TV show Punto Final.