A resurgence of illegal fishing in northern Australian waters is being driven by a complex mix of economic, social, cultural and pandemic-related factors that enforcement measures alone cannot address, new research to emerge from the Charles Darwin University has found.

Funded by the Australian Centre for International Agricultural Research (ACIAR) and co-developed by Indonesia’s National Research and Innovation Agency, and Nusa Cendana University, the study has examined the drivers of illegal small-scale fishing incursions into the Australian Fishing Zone (AFZ) – the area covering waters from three to 200 nautical miles off the Australian coast.

Illegal Indonesian fishing in the zone has been a persistent issue for five decades. Some 361 boats were apprehended in the 2005–06 financial year. Despite sustained government investment in surveillance and enforcement, incursions have risen sharply since the COVID-19 pandemic, with 337 boats intercepted in 2021 and 2022.

By January 2025, 172 vessels had already been intercepted in the current financial year.

Fieldwork conducted across four communities in Nusa Tenggara Timur Province, eastern Indonesia, identified seven broad categories of behavioural driver: economic and livelihood pressures, COVID-19 related factors, psychological motivations, environmental conditions, cultural and historical ties, social dynamics, and policy and management responses. Within those seven categories, researchers identified a further 28 individual drivers.

Professor Natasha Stacey, Professor of Environmental Science at CDU and leader of the research team, said the drivers frequently overlap.

“For example, during COVID-19, economic hardship among fishing communities increased,” Professor Stacey said. “However, financial difficulties alone are not sufficient to entirely explain the strong resurgence of illegal fishing, which was likely prompted by a combination of financial hardship, the discovery of new fishing grounds abundant in sea cucumber, and willing patrons to support such ventures into the AFZ.”

The research also incorporated perspectives from women in affected communities, examining the risks and impacts associated with male relatives engaging in illegal fishing.

“Women research participants expressed that the limited employment or other livelihood options for their menfolk in their communities is a motivating factor to fish in the AFZ,” Professor Stacey said.