Tiger shark
REproduction
Monitoring

In collaboration between Pelagic Divers Fuvahmulah and Fuvahmulah Dive School, we are running one of the most detailed pregnancy monitoring initiatives for tiger sharks anywhere in the world. To date, we have documented over 150 pregnancies, using long-term Photo-ID, repeated re-sightings, and other indicators to track individual females throughout their reproductive cycles.

Our monitoring follows each female from the first moment she is suspected to be pregnant, through the final stages of gestation, until the point when she is no longer pregnant, allowing us to estimate:

Pregnancy Duration

Timing of conception and parturition

Site fidelity during gestation

We rely heavily on identifying mating scars, enlarged abdominal profiles, changes in body condition, and re-sighting timelines to determine reproductive state. These indicators allow us to build individual reproductive histories across multiple years, offering an unprecedented view into tiger shark reproductive ecology.

Preliminary patterns suggest that some females show seasonal residency linked to the monsoon period, with predictable phases of presence during early to mid-gestation, followed by prolonged absences that may correspond to pupping migrations. By documenting these movements, we can begin to understand where Fuvahmulah fits within the broader reproductive cycle of the Indian Ocean tiger shark population.