The recent addition of a new service at the Port of Charleston underscores the win-some, lose-some nature of the fiercely competitive global shipping industry.

Over the course of the year, the State Ports Authority has lost a regular call to a key rival, snagged some business back from that same competitor and added some new routes.

"It's the nature of the beast. They come and they go," said Byron Miller, SPA spokesman.

The ports authority is wrapping up the calendar year with new service, courtesy of Mediterranean Shipping Co., or MSC, which recently added Charleston as the last outbound call in weekly service to Europe.

The first vessel, the MSC Lugano, called at the SPA's North Charleston terminal last week. The new service will increase the company's local ship calls to an average of five a week.

With Charleston as the last outbound port, and with a transit time of just 10 days to the next destination in Valencia, Spain, local maritime officials hope to attract more export cargo destined for that part of Europe. The new service also offers direct calls at the Italian ports of Naples and La Spezia, and to Sines in Portugal.

"The potential is quite good in Charleston," said Allen Clifford, who is executive vice president of MSC USA. "Charleston is one of our larger ports to the Mediterranean."

The SPA added other services this year linking the U.S. East Coast with ports in India, Asia and northern Europe, bringing thousands of containers to local docks.

But nothing is to be taken for granted in the shipping business, as recent scheduling changes demonstrate.

For example, Maersk Line, the world's largest ocean carrier, said last month it was switch- ing its eastern Mediterranean service from Charleston to Savannah, taking with it 52 vessel calls a year.

Maersk said that decision was driven partly by "customer needs," noting some clients had a "geographical preference" to move their containerized cargo through Savannah.

But the tables can be turned. The SPA snared some business away from its Georgia rival in July when Latin America's largest shipping company moved its East Coast of South America service to Charleston from Savannah.

The move by Compania Sudamericana de Vapores of Chile brought 52 additional vessel calls annually.

Charleston benefited from its strong Latin American business in another instance when Maersk said in September that it was "realigning" its service to Brazil. Although the company merged two routes into one, the decision brought additional weekly vessel calls to the Holy City.

Maersk, the SPA's biggest customer, said the change was needed to improve coverage for the Brazilian market, where the Port of Charleston has built a strong market share. Charleston handles an estimated 25 percent of all container cargo flowing between South America's east coast and U.S. ports from Virginia to Miami.

Miller said the shifts reflect the way shipping lines constantly review operations to improve efficiency.

He noted that Maersk's Brazil service originally stopped in Charleston but was later moved to Savannah. Now it's back again.

"All the carriers are looking at what they're doing and why they're doing it," Miller said. "If you average all this out it's about the same."

Reach Peter Hull at 937-5594 or phull@postandcourier.com.