Download the publication
Summary
West Pacific leatherback sea turtles (Dermochelys coriacea) are a Critically Endangered leatherback population that has declined by nearly 90% in recent decades. They face ongoing threats from fisheries bycatch throughout their migratory range. To address critical data gaps regarding leatherback abundance and distribution in New Zealand’s waters, the Department of Conservation’s Conservation Services Programme (DOC-CSP) contracted Upwell Turtles (Upwell), in partnership with Monash University and Earth Sciences New Zealand, to design and implement New Zealand’s first fishery-independent aerial survey targeting leatherbacks in the Bay of Plenty. This multi-year project aimed to estimate minimum abundance, characterize distribution within a known bycatch hotspot and a control site, and evaluate environmental conditions associated with turtle presence.
The project successfully established local survey capacity, refined survey design through stakeholder consultation, completed observer training, and conducted aerial surveys during the expected seasonal peak for leatherback presence. Although no leatherbacks were detected—likely reflecting anomalous environmental conditions and atypically low regional turtle presence—surveys confirmed detectability by documenting one turtle just outside the survey area and generated substantial auxiliary data on marine megafauna and ecosystem indicators. The project demonstrated the feasibility of aerial surveys in New Zealand waters, identified key logistical and environmental constraints, and highlighted the need for greater survey flexibility, expanded effort and continued investment in fishery-independent monitoring. These findings provide an essential foundation for future research and management aimed at reducing leatherback bycatch and improving protection for this transboundary, critically endangered population.
Publication information
Shillinger, G., Finucci, B., Benson, S., Dunn, M., Forney, K., Fullmer, S., Reina, R. 2026. Aerial survey of leatherback turtles in the waters off North Island, New Zealand. Report prepared by Upwell Turtles for the Department of Conservation, Conservation Services Programme. 45 p.
No results