Revenue for the half to December increased from $63.6million to $87.6million, earnings before interest and tax rose from $16.1million to $24.3million and after-tax profit was up from $8.7million to $15.7million.
However, King Salmon has estimated second-half profitability is expected to be about $13million to $14.5million lower than the $15.7million result - a range of $1.2million-$2.7million.
This would be due to lower sales volumes, a de-acceleration of harvesting, increased fish mortality and increasing feed costs, the company said.
King Salmon shares, up 46% on a year ago, eased down 4% on yesterday's news, trading at about $1.91.
King Salmon's chairman, John Ryder, said favourable growing conditions and strong demand for its premium King salmon products enabled the company to deliver additional volumes.
However, he cautioned the situation for second-half trading had become more challenging.
``The extraordinarily hot summer has impacted the survival rates of our King salmon, and this will be a principal factor behind an anticipated reduction in profits for the second half,'' Mr Ryder warned.
King Salmon sales were up 29%, to 4392 tonnes, 2294 tonnes being sold in New Zealand, up 13%, and a 70% gain in North American markets, where tonnage rose to 1158 tonnes.
Average prices per kilogram rose from $18.70 a year ago to $20.
The company's aquaculture team was actively preparing the salmon farms in anticipation of the warmer summer months, which this year have had well-above-average water temperatures.
``Our recently commissioned higher-flow sites have lessened the impact of the sustained heat, although, like many other farmers on land and in the sea, we have had associated performance and survival challenges,'' Mr Ryder said.
He said because of the temperature issue, he expected growth in sales volumes would be affected during the second-half trading, and into full-year 2019.
King Salmon would update the market in detail after summer was over, he said.
``Including an update on our progress towards a long-term solution to combat the risk of increasing sea temperatures,'' he said.
For the half, King Salmon increased its cash and equivalents from $10.6million to $15.5million on a year ago, and borrowings from the BNZ are unchanged, at $10million drawn from a $30million facility.
A fortnight ago, King Salmon said it would continue to push for more of its salmon farms in the Marlborough Sounds to be moved, following a report by an independent panel recommending to the Government that three of the six farms be relocated, The New Zealand Herald reported.
The independent panel released the report to the previous National government in July 2017, following public hearings in April and May last year.
Fisheries Minister Stuart Nash said he was ``some months'' away from making a decision, and released the report to enable the people and groups who made submissions to study it while he considered the next step.
Mr Ryder said yesterday: ``The panel recognised the `distinct environmental advantages' of higher-flow sites, as well as the positive social and economic outcomes.''
