REEFER containership capacity is expected to increase 22 per cent over the next five years at the expense reefer ships, says Drewry's latest Reefer Shipping Market Annual Review and Forecast.

Reefer box capacity is expected to grow from 1.6 million FEU slots in 2013 to 1.9 million slots in 2018. But this is not expected to adversely impact vessel utilisation levels thanks to strong cargo growth, said the report.

Reefer volumes are forecast to rise 20.5 million tonnes over this period, 16.5 million tonnes by organic growth and four million tonnes from displacing reefer ships.

Overall seaborne perishable reefer trade will increase 17 per cent between 2013 and 2018, providing an additional 16.5 million tonnes of cargo, said the report.

"As a result of the expected cargo growth, reefer container slot utilisation levels will be unchanged in 2015 and only marginally lower thereafter," said Kevin Harding, the report's editor.

"Meanwhile, the specialised reefer sector is forecast to shrink further as a result of scrapping and a virtually empty order book."

Although the specialised reefer fleet provided little more than seven per cent of overall reefer capacity, it carried almost 28 per cent of the estimated perishable reefer cargo in 2013.

"The specialised reefer operators peaked some years ago, in terms of cargo volumes, and now face continued falling volumes and market shares," Mr Harding said.

Drewry estimates that the worldwide seaborne perishable reefer trade rose at an annual rate of 3.2 per cent in the 10 years to 2013, reaching 98 million tonnes last year. Meat and fruit, with fruit rising 9.3 per cent a year, drives growth.