Dolphins emerge as most frequently sighted marine mammals in Gulf of Kachchh
Dolphins have emerged as the most frequently encountered marine mammals in the southern Gulf of Kachchh, with a latest scientific survey recording 64 sightings involving 193 individual dolphins between October 2023 and February 2025. The findings underline the importance of Gujarat’s shallow coastal waters, reef systems and tidal channels as key habitats for coastal dolphin populations.
The study was conducted by the Gujarat Ecological Education and Research (GEER) Foundation, an autonomous body under the Gujarat Forest Department. The assessment, titled Status Survey of Dugong and Other Marine Mammals, and Ecological Assessment of Seagrass Habitats around Narara and Adjacent Islands, Gulf of Kachchh, was carried out in and around the Marine National Park and Marine Sanctuary, the country’s first marine protected area.
“The boat-based surveys covered reef edges, tidal channels, island margins and shallow coastal waters and recorded a total of 177 verified marine megafauna sightings involving 342 individuals. Dolphins accounted for 36.2% of all recorded sightings, making them the dominant marine mammal group in the survey,” said Shri Arjun Modhwadia, Minister for Forests and Environment.
“The survey provides a detailed picture of where dolphins are using the Gulf. Narara Reef recorded the highest number of sightings at 14, involving 39 dolphins. The Dedeka–Mundeka island complex followed with 12 sightings involving 41 individuals, while Pirotan Island recorded 11 sightings involving 32 dolphins. Dhani Island accounted for nine sightings involving 28 individuals, and eight sightings involving 26 dolphins were recorded in the coastal waters of Sikka. Another 10 sightings, involving 27 individuals, were recorded at other surveyed locations,” said Vinod Rao, Principal Secretary, Forests and Environment Department.
“Our researchers found that dolphins were particularly associated with reef margins, island edges, tidal channels and open waters. These areas are likely to provide both movement corridors and productive feeding grounds. Strong tidal currents in the Gulf promote nutrient mixing and can concentrate fish, creating favourable conditions for dolphins that feed on schooling fish,” said B.P. Pati (IFS), Director, GEER Foundation.
The Dedeka–Mundeka island complex appears to be especially important as a dolphin movement corridor. Dolphins were frequently observed travelling along deeper reef margins and tidal channels between the islands. The report suggests that these channels, influenced by strong tidal currents, support fish aggregation and consequently attract higher-level marine predators such as dolphins.
Pirotan Island also recorded regular dolphin activity, particularly in open tidal channels between reef systems. At Dhani Island, dolphins were consistently observed along the eastern and southeastern margins, where strong tidal currents interact with deeper channels. These hydrodynamic conditions are believed to concentrate fish schools and create favourable feeding opportunities.
Dolphins sighted throughout the year
“One of the notable findings is the year-round occurrence of dolphins. Sightings were recorded during winter, summer and post-monsoon seasons. Winter produced the highest number, with 26 sightings, followed by 21 during post-monsoon and 17 during summer. The consistent presence across seasons suggests that at least a portion of the dolphin population may be resident or semi-resident in the southern Gulf rather than simply passing through during a particular season,” *B.P. Pati* added.
The report, however, cautions that species-level identification was not possible for all dolphin sightings during the survey. The observations provide clear evidence of the occurrence of the Indian Ocean humpback dolphin (Sousa plumbea) in the Gulf of Kachchh, while the species identity of some other dolphin sightings could not be conclusively established from the available field observations. Further systematic surveys and species-level verification are required to better understand the diversity, distribution and occurrence of other dolphin species in the Gulf.
Fascinating Dolphin behaviours
The animals also displayed a range of behaviours during the survey. Researchers observed coordinated group swimming, regular surfacing, directional movement along tidal currents and occasional feeding activity. Group sizes varied considerably—from solitary dolphins to aggregations of up to 16 individuals—reflecting the flexible social behaviour of coastal dolphin species.
The habitat analysis reinforces the importance of tidal channels to dolphins. Of the 177 marine megafauna records, 31 dolphin sightings occurred in tidal channels and open waters, compared with 22 around reef platforms and 11 in seagrass meadows. In contrast, reef platforms were particularly important for marine turtles, while seagrass meadows retain special significance as dugong feeding habitats.
“The latest findings therefore portray the southern Gulf of Kachchh as a dynamic marine habitat where reefs, seagrass meadows and tidal channels work together to sustain diverse marine life. For dolphins, the tidal channels and open coastal waters appear to be especially critical, providing routes for movement as well as access to fish-rich feeding grounds,” said Dr Jaipal Singh, Principal Chief Conservator of Forests (Wildlife).
The recent study provides an important baseline for future conservation efforts.
“With dolphins recorded consistently across seasons and at several locations, the study establishes an important baseline for future conservation. Continued systematic surveys, species-specific identification, monitoring of fishing and vessel activity, and protection of productive coastal habitats will be essential to understand population trends and ensure that the Gulf of Kachchh remains a secure home for Gujarat’s coastal dolphins,” said Amitkumar Nayak (IFS), Deputy Director, GEER Foundation.