Scientific data collection

Science as a tool for conservation

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. 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, collaborating with multiple scientific institutions. We are also tracking movements through satellite and acoustic tags.

Our focus

Population size and structure
Thanks to dedicated photo-identification efforts we can infer population size and structure.
Movements and residency
Thanks to the combination of satellite and acoustic tags, photo-identification and genetics we are starting to better understand movements and residency patterns of the Nosy Be population.
Socio-economic value
Through interviews with tourists and operators we are quantifying the socio-economic value of live whale sharks as an economic asset to Madagascar’s economy, another argument for protecting their habitat.
Feeding ecology
Through collaborations with specialized teams and sampling we are trying to better understand the drivers of whale shark presence: the food sources they rely upon.
Marine megafauna
Through our trips we also record species name and GPS location for each encountered marine megafauna species, with the aim to grow a species list.

Whale shark photo-identification

A unique non-invasive global conservation effort

Our team collects photo-identification data for each encountered whale shark, which is then analysed through a unique algorithm adapted from NASA’s star-mapping telescopes. Photos of whale shark spot patterns (left-side) are collected throughout the Indian Ocean, and further afield, then are uploaded onto a global online database of whale shark sightings ( This enables us to investigate the connectivity of Madagascar to other regional aggregations through the movements of individual sharks. So far, we have identified more than 525 individual juvenile whale sharks; yet, none of these individuals have been spotted elsewhere in the world.

Through this work, we provide information necessary for appropriate management measures in Madagascar and the Western Indian Ocean through publications and data sharing.

Want to contribute data as a citizen scientist? Check out how here.

Identified whale sharks since 2015

Scientific publications