Mirissa submarine canyon bathymetry: Sperm Whale (Physeter macrocephalus) deep squid hunting?

The southern coast off Mirissa and Dondra Head features one of the narrowest continental shelves in the Indian Ocean. Within just 4 to 6 nautical miles from shore, the seabed plunges abruptly from 50 meters down to over 1,500 meters into a deep submarine canyon system. This bathymetric chasm channels deep oceanic upwelling currents carrying nutrient-dense water to the surface, nourishing vast populations of meso-pelagic squid (Histioteuthis). Resident pods of female and juvenile Sperm Whales (Physeter macrocephalus) utilize this steep canyon to make 45-minute foraging dives down to 1,000 meters.