At the height of strike action Tauranga was processing 50,000 containers a month, up from 40,000 prior to the strike. That's now dropped back to about 45,000 containers.
Mark Cairns, chief executive at Port of Tauranga said his company "coped with the volumes."
"It challenged a lot of assumptions about how much we can do," he said. "We have still retained some of that volume."
In July the world's biggest container shipping line, Maersk, lifted container rates between New Zealand and the US in the first of what may be a series of price increases as it seeks a return to profit. It increased rates by US$150 per 20-foot container and US$350 per 40-foot container.
The container industry contributes about US$380 billion in freight rates to the global economy or about 5 per cent of total world trade, according to United Nations figures.
The New Zealand Transport Agency's National Freight study forecasts up to a 75 per cent increase in the volume of commodities by 2031, while costal shipping volumes are predicted to double to 9 million tonnes. Tauranga and Auckland currently make up about 70 per cent of New Zealand exports.
Last week, POA board members met to review the company's financials for the six months ended June 30.
In April, it flagged a weak second-half result, following on from a flat first-half underlying profit. Net profit was $18.6 million in the six months ended December 31, though $4.8 million of that was a tax gain that is unlikely to recur. Sales increased by 9 per cent to $96.6 million, though operating costs climbed 12 per cent.
Tauranga posted a record 22 per cent increase in first-half profit to $34.6 million. Sales increased 14 per cent to $105.7 million. The port's shares fell 0.4 per cent to $11.40 and have soared 14.4 per cent so far this year.
Auckland's Gibson said container volumes fell as a result of strike action but he is "very pleased" with the results of its multi-cargo division in the latest six-month period. But he also sees the rival as a benchmark operator.
"You could say the Ports of Auckland and the Port of Tauranga have an underlying basic business philosophy and strategy which is similar - one of them is just a hell of a lot more successful than the other and that's Tauranga," Gibson said. "I believe that's to do with their can-do attitude."
"They're very good competitors, they're quick on their feet, they run a good shop - we've got to get to that stage on par or better than Tauranga for the good of NZ Inc."
"If we have got a similar cost base to Tauranga and similar productivity - that's going to be really good for New Zealand's supply chain," Gibson said.
Ports of Auckland and Port of Tauranga have been unable to forge a direct alliance as they compete for freight but both see strategic value in their partnership at Marsden Point's, Northport. POA owns 19.9 per cent of Northland Port Corp alongside Northland Regional Council, which in turn owns about 54 per cent of Northport. Northport's other investor is Port of Tauranga.
Northport has been pushing for a greater share of North Island trade from Auckland and Tauranga. It has about 180 hectares of land, owned by Northland Port, which is currently only at 50 per cent capacity. Auckland and Tauranga have previously stated they see Northport as a "long term investment" and all three ports need to remain open to keep up with growing demand.