PORTS of Auckland in New Zealand has announced an unaudited net profit of NZ$18.6 million (US$15.2 million) for the six months ending December 31, 2011.

The result includes NZ$4.8 million in after tax gains that are not expected to reoccur. Removing those gains, the underlying profit for the first half of the port's financial year amounted to NZ$13.8 million, down from NZ$14 million profit recorded in the same period a year earlier.

Revenue rose by nine per cent year on year to NZ$96.6million, while operating costs excluding depreciation increased by NZ$5.7 million, or 11.5 per cent.

Total container volume during the period under review rose slightly by 0.2 per cent year on year to 454,234 TEU. Within this result, full import container volume grew by 1.7 per cent to 169,557 TEU, which a statement from port authorities said reflected a "relatively subdued economic environment".

First half transshipment volumes were down 6.3 per cent year on year. Bulk and breakbulk volumes stood at 1,897,094 tonnes, up only 0.9 per cent year on year.

The gains reflected in the first half results, which are not expected to reoccur include a change in shipping schedules which created a 20 per cent increase in empties for the period; revenue from salvage services provided during the grounding of the container ship Rena in the Bay of Plenty.

A record number of cruise ships for the Rugby World Cup; a 14 per cent increase in vehicle imports influenced by the Japan earthquake and the introduction of stricter emission standards on Japanese imports from January 1 2012; and prior period taxation adjustment due to timing.

Expectations for the second half of the financial year are described by port authorities as being "uncertain given the costs of industrial action and associated loss of business".

Said port CEO Tony Gibson: "It's been a challenging period for the business. Second half results will be impacted by decreased container volume associated with recent industrial action and loss of the Maersk and Fonterra services."

The port authority has been engaged in a long dispute with the Maritime Union over the port's proposal to introduce flexible docker shifts to prevent wages from escalating.

The row over wages has prompted rolling strikes and lock-outs. However, both parties have resumed negotiations after an Employment Court judge granted an injunction and the port's management abandoned a plan to hire external stevedoring contractors.