Despite surpassing total harvest volume estimates in the first quarter of 2020, Grieg Seafood's earnings took a hit, the result of biological challenges in its northern Norway operations.

The group harvested a total of 18,362 metric tons in first quarter, 9 percent more than it had estimated and communicated in its Q4 2019 results.

Grieg's Finnmark operations were hit by winter ulcers in the first quarter, which dragged achieved earnings before interest and tax (EBIT) down to NOK 4.56 per kilo, 81 percent less year-on-year.

A large amount of salmon was also harvested from a site infected by infectious salmon anemia (ISA), which increased costs per kilo.

The company is currently assessing methods to avoid such situations in the future.

However, the rest of the group's operations during the quarter were in line with expectations.

The final first quarter report will be released on May 7.

The company had a solid year in 2019, with earnings before interest, tax, depreciation and amortization (EBITDA) jumping 12 percent to NOK 1.49 billion (€133 million/$145 million).

For the next five years, Grieg says it will be focused on increasing sustainable farming practices and aiming for an annual harvest of at least 150,000 metric tons by 2025.