The Toronto Wildlife Centre said it had rescued 31 ducks — with at least a dozen more en route — that were slicked with oil by late Tuesday afternoon.
The oil is believed to come from a truck that crashed at Highway 401 and Highway 427 on Monday night. The oil leaked into Mimico Creek and eventually covered the ducks.
"They're literally soaked in oil," said Toronto Wildlife Centre spokeswoman Julia Pietrus.
"But they're coming in alive and angry, which is a good sign."
Pietrus said they have set up two bathing stations as they scramble to clean the ducks.
— Toronto Wildlife Ctr (@TWC_Wildlife) July 14, 2015
"Over the next few days, we're going to be bathing a lot of ducks."
She said they then give the ducks activated charcoal through a tube into their stomachs.
"The reason we do that is as if they've been preening the oil before we caught them, the oil can cause really serious digestive issues so we give them charcoal to stop that process."
Then they give them a medical grade sugar to keep their blood-sugar levels up "because the bathing process itself is incredibly stressful."
Pietrus said the wildlife centre, a charity, was running out of soap until Dawn said it was on its way with a donation.
She said the centre could use towels and more donations to help them cope with the influx of animals.
Once the birds have been cleaned and deemed healthy, they'll be released back into the wild, Pietrus said.
Pietrus said fire and police have told them the substance spilled is mineral oil.
"It doesn't really smell like mineral oil," she said.
"We have our doubts."
Workers with the city of Toronto have placed booms at the site and the mouth of the creek to prevent the oil from spreading.
Staff from Ontario's Ministry of the Environment are also at the site of the spill.
Pietrus said another dozen wildlife workers — mostly volunteers — are tracking the eight kilometre stretch of Mimico Creek as they search for more oiled birds.
The fear, she said, is the oil slick getting into Humber Bay Park on Lake Ontario, which is a protected preserve replete with wildlife.
"If it gets that far, it's going to be pretty bad," Pietrus said.
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