South Korea’s offshore fisheries output sank to a 44-year low in 2016 due to tumbling fish stocks caused by a combination of Chinese illegal fishing, climate change and overfishing, a report showed Tuesday.

The country’s inshore and offshore fisheries production came to 923,000 tons last year, down 12.7 percent from the previous year and the lowest yearly catch since 1972, according to the report by the Korea Maritime Institute.

The KMI said Chinese fishermen’s illegal fishing in South Korean waters was the main culprit, with the loss of maritime resources reaching 100,000 tons to 650,000 tons per year.