Environment Canada officials were not able to find a source for the fuel noticed last week in Delkatla Slough.Spokesperson Tracy Lacroix-Wilson said her office was informed Nov. 21 of a hydrocarbon sheen flowing into Delkatla Slough Bird Sanctuary. The Department of Fisheries and Oceans and Coast Guard Environmental Response attended on November 21 and could not locate any sheening. Environment Canada Enforcement Officers looked into several possible sources of the spill but the origin and the quantity still remain unknown. There have been no reports of affected fish or wildlife, she says."Environment Canada takes these matters seriously and should a sheen occur in the future, officials would take action to prevent any contamination from entering the bird sanctuary," she said.