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Pacific Conservation Biology Pacific Conservation Biology Society
A journal dedicated to conservation and wildlife management in the Pacific region.

Diversity and distribution of cetaceans in the Republic of Palau

Olive Andrews A B C * , Tiare Holm D , Daniel Burns A E F , Cory Ann Hom-Weaver G , Carlos Olavarria A H , David Orrukem I , Rechelluul Percy J and Rob Williams K
+ Author Affiliations
- Author Affiliations

A South Pacific Whale Research Consortium, PO Box 3069, Avarua, Rarotonga, Cook Islands.

B Whaleology, Waiheke Island, Auckland 1081, New Zealand.

C Institute of Marine Science, University of Auckland, Auckland 1142, New Zealand.

D Sustainable Decisions, Ngardmau, Republic of Palau.

E Marine Ecology Research Centre, Southern Cross University, Lismore, NSW 2480, Australia.

F Environmental Resources Management, West Perth, WA 6872, Australia.

G Bio-Waves, Inc., Encinitas, CA 92024, USA.

H Centro de Estudios Avanzados en Zonas Áridas, La Serena, Chile.

I Bureau of Foreign Affairs and Trade, Melekeok, Republic of Palau.

J Bureau of Marine Resources, Koror, Republic of Palau.

K Oceans Initiative, Seattle, WA, USA.

* Correspondence to:

Handling Editor: Rochelle Constantine

Pacific Conservation Biology 30, PC23021
Submitted: 18 May 2023  Accepted: 12 November 2023  Published: 7 December 2023

© 2024 The Author(s) (or their employer(s)). Published by CSIRO Publishing



Until recently, very little was known about the species diversity and occurrence of cetaceans in the Republic of Palau. A dedicated scientific investigation into the occurrence and distribution of island associated cetaceans in Palau was conducted in 2012 and 2013.


The aim of this project was to investigate the diversity and distribution of cetaceans in Palau to inform management and build local capacity in cetacean science.


Following a feasibility study in 2010, a vessel-based visual and acoustic line transect survey was conducted in 2012, covering a survey area of 4319 km2. The survey was repeated and expanded in 2013 using aerial methods. Additionally, small boat work was conducted in areas with high cetacean density to obtain genetic, acoustic, and photographic samples. In 2019, a vessel-based visual and acoustic survey of the Southwest Islands was conducted.

Key results

By combining the survey results with anecdotal sightings, a cetacean species inventory for Palau was established. The presence of 15 species was confirmed, while four species were identified as probably present and three as likely.


Survey results contributed to the management of cetaceans in the Palau Marine Mammal Sanctuary. The surveys raised local interest in cetaceans and, through public outreach and training, precipitated advancements in capacity building for cetacean management, along with a baseline for ongoing monitoring.


This study provided the first systematic, scientific investigation using multiple survey methods into the occurrence and distribution of cetaceans in Palau, highlighting the importance of conserving cetacean populations in this region.

Keywords: cetaceans, conservation, distribution, diversity, inventory, management, Palau, species.


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