Unlike conventional fuel, the oil from tar sands is denser than water and will sink to the ocean floor during a spill, making cleanup of a spill much more difficult.

A 2102 spill of tar sands crude oil in Michigan's Kalamazoo River has taken over five years to clean up.

With the incoming Trump administration, scientists and environmentalists say more knowledge is needed to create effective policies on oil sands development, transport and disaster response in the event of an ocean spill.

By Hannah Albarazi - Follow her on Twitter: @hannahalbarazi.