Background:
Until recently, very little was known about the species diversity and occurrence of cetaceans in the Republic of Palau (ROP). The first scientific investigation into the status of cetaceans in the ROP was conducted over two seasons in 2012-2013. A ship-based visual and acoustic line transect survey was conducted over a 13-day period in 2012, completing 19 separate transects covering a survey area of 4,319km2 of coastal waters. The survey tracks were repeated in 2013 using aerial survey methods. Small boat work was also conducted in identified areas of high cetacean density from which genetic, acoustic, and photographic samples were acquired. A visual and acoustic survey of the Southwest islands of Palau was conducted in 2019. Survey results combined with confirmed, long- term anecdotal sightings information has resulted in a cetacean species inventory for the ROP, confirming the presence of 15 species and identifying a further 4 as probable, and 3 as likely occurring. The information obtained during the surveys contributed to the management of cetaceans in the Palau Marine Mammal Sanctuary and Palau National Marine Sanctuary. The surveys raised local government and community interest in cetaceans and, through corresponding public outreach and training, precipitated advancements in capacity building for cetacean management, along with establishing a baseline for ongoing monitoring.
Mission:
This is a collaborative research project to be conducted between Feb– April or Oct-Nov 2024 which aims to repeat the survey design catalyzing scientific partnerships through affiliation with the South Pacific Whale Research Consortium, and to increase local expertise in cetacean monitoring. The project will use genetic, acoustic, and photographic matching to assess the abundance, distribution, and cultural connectivity of cetaceans in PNMS deploying a variation of methods and scientific partners to achieve maximum scientific and conservation impact.
The project will also include training government officials and community members in cetacean research and monitoring techniques. This training will help ensure that ecotourism development will have minimal negative impact while maximizing educational and economic benefits. Additional training will target government and university partners to enhance understanding of cetacean habitats and considerations for the development of the PNMS monitoring plan, particularly in areas where exiting tourism effort overlaps with cetacean hotspots. Ultimately, this project intends to answer the following research questions:
1. Which species of cetaceans are found in the PNMS and what is their status?
2. Is Palau a migratory corridor, breeding, or feeding destination for cetaceans, and therefore what are the management considerations for whale watching operations?
This project will answer these research questions by meeting the following objectives:
1. Progress a cetacean species inventory for Palau;
2. Generate abundance estimates for cetacean species using visual and acoustic survey methods;
3. Enhance understanding of cetacean population structure using genetic sampling methods;
4. Define areas of important habitat for cetaceans in particular mother/calf pairs;
5. Utilize species and habitat information generated from this survey to inform management and conservation goals of PNMS;
6. Utilize species and habitat information generated from this survey to inform management of the growth and sustainability of whale and dolphin watching tourism.
Application:
Repeating the survey design from 2012, a systematic, visual, and acoustic line transect survey will be undertaken from a live aboard catamaran in order to identify cetacean species and generate abundance estimates for common species. Photo identification, biopsy samples, acoustic recordings, and behavioral notes will be collected. Passive acoustic recording will be conducted using a towed hydrophone array. Additional long-term recorders will be deployed at places of interest to determine seasonal occurrence and diversity of cetaceans in relation to other ecosystem characteristics. Genetic samples will be analyzed at the University of Auckland. Recordings from the towed array hydrophones will be analyzed by cetacean acousticians from SPWRC for species identification and abundance. Vocal repertoire analysis for sperm whales will be conducted by Dr Taylor Hersh. Photo identification will be compared to regional databases and catalogues for key species through Happywhale. The survey will be partnered by local agencies who will receive specialized training by the principal investigators both on and off the water.
A seasonal report will be produced and submitted to the Government, SPWRC/IWC and a full write up at the termination of the project which will be submitted to be published in peer reviewed journals.