Higher cost of diesel fuel due to maritime usage?

Read another trucking industry insider report today in which a transportation analyst was recommending trucking companies budget up to an additional .35 cent's per litre or $1.30 per gallon for up to 3 years while the shipping industry and refineries adjust to the increased demand for ULSD over bunker oil. Don't know about anyone else but for me as a Canadian between our pathetic stock market performance, our lousy Canadian dollar and now likely substantially higher fuel cost's the affect on our travel budget will certainly have any affect on our travel spending.
Curious to know whether ship engines can switch back and forth between ULSD and heavy bunker oil.