The Madagascar Whale Shark Project’s main scientific objective is to establish the occurrence, residency, and population structure of whale sharks off Nosy Be, Madagascar.
This is achieved through the collection of standardised sighting data, such as the GPS location, size and gender of all individuals, coupled with photo-identification for every encountered shark. Data is collected while free diving from boat operator Les Baleines Rand’eau, our local operating partner. When possible, we also collect small skin samples to examine diet and movements using biochemical markers (stable isotopes and fatty acids), along with population genetics and genomics studies, with the collaboration of multiple scientific institutions.
Whale shark photo-identification data is compared with photos collected throughout the Indian Ocean, and further afield, using a global online database of whale shark sightings (www.whaleshark.org). This enables to investigate the connectivity of Madagascar to other regional aggregations through the movements of individual sharks. So far, we have identified more than 300 different juvenile whale sharks, yet none of these individuals have been spotted elsewhere, yet.
We have also deployed satellite tags on whale sharks in 2016 in order to better understand their movements. You can read our publication here.
(c) Endangered Species Research (ESR), Diamant, S. et al. 2018
Finally, we provide information necessary for appropriate management measures in Madagascar and in the Western Indian Ocean through publications and data sharing.
The objectives of the project are to establish:
1 – Baseline population abundance of Nosy Be whale sharks to establish future population trends. This will act as a marker of management success;
2 – Information on local and international movements of whale sharks from North-West Madagascar using satellite tags and collaborative photo-identification, to establish whether a true decline in regional whale shark numbers has occurred, or rather a shift in their centre of abundance;
3 – Population structure of whale sharks present (size and gender distribution);
4 – A Code of Conduct to ensure sustainable whale shark tourism;
5 – Connectivity with other whale shark aggregations in the region.
Check out our project updates for more information on our current work.