In general, things are going well for operators of vehicle carriers. The ships that carry cars and trucks from their manufacturers to their markets have been commanding record freight rates.

Even though economic clouds have softened the automobile market, vessel capacity remains tight, with few orders at shipyards threatening to bring new car carriers into the market.

But since the start of this year, there has been one major problem: congestion at ports in Australia caused in part by efforts to prevent a pest with an unpleasant sounding name from entering the country.