About the Authors

Gail Campbell-Smith

primatelass@gmail.com

Affiliation Durrell Institute of Conservation and Ecology, University of Kent, Canterbury, Kent, United Kingdom

Miran Campbell-Smith

Affiliation Orangutan Information Centre, Human-Orangutan Conflict and Mitigation Programme, Medan, North Sumatra, Indonesia

Ian Singleton

Affiliation Sumatran Orangutan Conservation Programme, PanEco Foundation, Medan, North Sumatra, Indonesia

Matthew Linkie

Affiliations Durrell Institute of Conservation and Ecology, University of Kent, Canterbury, Kent, United Kingdom, Fauna & Flora International, Cambridge, United Kingdom

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: GC-S ML. Performed the experiments: GC-S MC-S. Analyzed the data: GC-S. Contributed reagents/materials/analysis tools: GC-S. Wrote the paper: GC-S ML IS.