Radio tags do the job

The scientists, from WWF-Indonesia, Conservation International, the State University of Papua and San Diego’s Hubbs SeaWorld Research Institute, tagged 30 whale sharks in late June in Cenderawasih Bay National Park, where they gather seasonally to feed. 

The fact that the tags need to be detected at relatively close range does not matter as the researchers will know where to return to in order to pick up signals and show how individual creatures commute on a regular basis.

Further, satellite tags detach after a period of time and are usually lost. The miniscule radio tags, the size of a pill, are there for life and will allow the researchers to monitor seasonal movements over many years.