An estimated 20 to 30 ducks, seabirds and other waterfowl have been "impacted" by last week's spill of fuel oil from a freighter into English Bay, according to Environment Canada officials.
Saul Schneider, manager of population conservation for the Canadian Wildlife Service, said one oiled bufflehead duck had to be euthanized and three more and a wigeon duck are in treatment following the release of an estimated 2,700 litres of bunker C oil.
Most of the oiled birds are still in the water – mainly at Jericho and Vanier parks in Vancouver – and Schneider said efforts are ramping up today to capture and clean them.
A wildlife rehabilitation centre has been set up at the HMCS Discovery.
Coast Guard officials said cleanup efforts are 90 per cent complete, but City of Vancouver manager Penny Ballem cautioned Tuesday tar balls could be still in the water and travel considerable distances.
"We will still have globules of oil wash up on the shore," she predicted.
Ballem said the city is lucky that it was a small spill that affected about six kilometres of shoreline, adding oil could have spread much further had it not been for good weather and tide conditions.
She said fish habitat is also a concern, but said long-term monitoring will be required to gauge any impacts.
The Vancouver Aquarium's ocean intake was temporarily shut off when the oil sheen reached it and the city had considered trucking in water if necessary.
According to city officials, the boom around the Marathassa was not secured until 5:53 a.m. Thursday, about 11 hours after the initial spill reports.
Work is ongoing to get a more precise estimate of how much oil escaped the bulk carrier, which was to load grain.
A malfunction in the new vessel caused the fuel oil to pool in the very bottom of the hull, from which it was somehow released out to the ocean.
The remaining oil in the bottom of the vessel is being warmed so it can be more easily pumped out and measured. That should help determine how much oil ended up in the water.
Ballem predicted the final amount spilled will end up at between 3,000 and 5,000 litres.
The Marathassa has been ordered detained by the federal government and its owners are to be held liable for costs.
There's a maximum liability cap of about $28 million for ship owners, after which a shipping association can cover another $162 million.
Marathassa Spill Presentation - City of Vancouver - April 14