The Wings Over Ocean project

CONTEXT AND MAIN ISSUES

Mapping fishing effort at sea is essential to assess ecological impacts and ensure sustainable and equitable management of marine resources. Yet in many parts of the world, particularly along the North African coast, a substantial proportion of artisanal and industrial fisheries escapes conventional monitoring systems.

Satellite‑based tools such as AIS (Automatic Identification System) and VMS (Vessel Monitoring Systems) are global references for vessel monitoring at sea. However, even when mandatory, these systems may be absent, non‑functional or intentionally switched off by crews. These gaps severely limit effective marine surveillance and the detection of illegal, unreported and unregulated (IUU) fishing, estimated to represent over one fifth of global catches.

In such data‑poor contexts, developing complementary and innovative approaches is essential. Certain marine species offer promising solutions, notably seabirds, whose offshore movements are closely linked to fishing activity. Audouin’s gull, in particular, actively follows fishing vessels to feed on discards. Its high‑resolution movements and offshore aggregations can thus indirectly reveal the presence and intensity of fishing activity, including in areas where satellite coverage is limited.

GOALS

Remotely detect fishing vessels through bio‑logging of seabird aggregations at sea, to complement and strengthen existing satellite‑based analyses.

METHOD

The Wings Over Ocean project equips Audouin’s gulls with miniaturised GPS devices and accelerometers, allowing fine‑scale tracking of their movements and behaviour at sea.

In a first phase, bird trajectories will be analysed in the Mediterranean, where AIS and VMS data are reliable and abundant. These comparative datasets will be used to train predictive models capable of identifying behavioural signatures associated with fishing vessel presence.

The models will then be applied to movements of the same birds during their post‑breeding migration along the African coastline, where vessel monitoring systems are limited or absent. Results will be cross‑referenced with existing satellite products to generate a more complete and robust map of fishing effort.

This approach treats seabirds as mobile, autonomous biological sensors, serving a major and systemic challenge: combating illegal fishing.

HOW IS THIS PROJECT INNOVATIVE?

Wings Over Ocean introduces a radically new approach by turning seabirds into sentinels of human activity at sea. Through bio‑logging, the project delivers precise, continuous behavioural data independent of traditional surveillance infrastructure.

Innovation is primarily technological and methodological, combining biological data, predictive models and satellite observations to detect fishing activity where standard sensors fall short, particularly for coastal and small‑scale fleets.

The project is also exploratory, revealing for the first time at large scale the interactions between seabirds and fisheries along the West African coast, a region that remains poorly documented.

By complementing existing tools, Wings Over Ocean paves the way toward more equitable and transboundary ocean surveillance, strengthening action against illegal fishing and contributing to improved marine resource governance.