Wednesday is International Seafarer's Day. As one of the oldest professions in the world, sailors play a crucial role in global ocean trade. Over 90 percent of China's imports and exports rely on ocean routes, but the country's senior seafarers are in high shortage. CCTV's Wu Lei fields this report from China's Guangdong province.

People always say being a sailor has advantages, like sailing around the world and experiencing different cultures. This is the second year for 25 year old Yang Yulong working on a ship. When talking about his job, he is still excited and full of expectations.

"As a new sailor, whenever the ship arrives at another country or a new port, I will be very excited during the whole sail. And I will try to become a captain in about 10 years. My wish is to drive a ship with our national flag to every corner of the world. This is my plan," said Yang Yulong, fresh seafarer of China Shipping Int'l Ship Management Company.

China now has over 650 thousand sailors and seamen, with only 10 thousand captains and 10,000 chief engineers. Senior sailors play a crucial role in shipping on the oceans. But in recent years, captains like Li Zhenmin has found it hard to find enough experienced shipmates in the company he works for.

"Most Chinese seafarers work on a ship for 8 months and have 4 months holiday. 8 months income will be his total income for a year. After deducting the taxes and other fees, this payment is not competitive any more," Li said.

Captain Li said there are only 1,000 senior shipmates in his company, but they need about 30% more.

Moving from a fresh sailor to a captain takes over 10 years of passing all sorts of tests and challenges, and life is not easy on the ship. Many experienced shipmates are also increasingly concerned about their families and future plans.

"Because our payment becomes less attractive, and working on an ocean-going ship is a very challenging and lonely job, it's often boring and tedium. Some experienced seafarers wanted to do some administrative work on the land and take good care of their families," said Sun Yongsheng, chief officer of China Shipping Int'l Ship Management Company.

Sun Yongsheng felt sad when some of his colleges left. He also said many countries like South Korea and the Philippines collect no taxes on seafarers' wages, but China collects around 20% of seafarer's wages through taxes.

"We hope the salary of senior shipmates can be more competitive, and expect some favorable polices on personal income tax. What's more we hope people could have more knowledge about our job. With their respect and inspiration, more young graduates could join us," said Li.

Without sailors' contributions to society, it will be very hard to enjoy food, clothes and products from other countries. It's estimated that 20,000 senior seamen will be needed in China by 2015.