Madison Maersk in Yokohama Bay, undated photo.
Maersk has not yet canceled any stops by its big transoceanic ships at the big Japanese ports. The large ships do not call at the small ports of northeast Japan, a mainly agricultural area served by smaller vessels that bring cargos down to major ports like Yokohama for transoceanic shipment.
Small ports close to the earthquake were heavily damaged by the earthquake and tsunami and could have severely impaired operations for months. Major shipping lines are still trying to decide what to do with cargos arriving in southern Japan for transshipment to northeast Japan.