Monsoon variability and sea surface temperature influence the presence of tiger sharks around Fuvahmulah, Maldives

Abstract Environmental variability plays a crucial role in shaping the site use of apex predators, yet its influence under human-modified conditions remains unclear. From August 2021 to March 2024, we conducted 911 visual surveys of tiger sharks ( Galeocerdo cuvier ) at Fuvahmulah, Maldives. We used photo-ID to identify individual tiger sharks, and agglomerative hierarchical clustering to classify sharks into residency clusters. We fitted generalized additive models to residency clusters and life-stage groups to test whether sea surface temperature, monsoon phase, lunar–tide interactions, and wind and wave metrics influenced shark abundance at the Tiger Harbour dive site. Models explained 24–38% of deviance and revealed that resident, relatively larger females preferred warm temperatures and monsoonal cycles, whereas transient, relatively smaller sharks responded more to weather patterns, wind direction, and lunar–tidal effects. Our results underscore that natural environmental rhythms continue to influence tiger shark sightings even under regular provisioning, informing ecological insights consistent with findings from other provisioned shark aggregations.