Study findings: ‘Sunderbans saltwater crocodile population shows steady growth’

Kolkata: The saltwater crocodile population in the Indian Sunderbans is estimated to be between 220 and 242, according to a new Forest department study released at Sajnekhali on Monday.

The report, titled Population Assessment and Habitat Ecology of Saltwater Crocodiles in Sunderbans 2025, was prepared through systematic surveys, GPS mapping and habitat characterisation and is expected to guide future conservation efforts. “A detailed population assessment exercise was conducted between December 2024 and February 2025 to assess the population status of saltwater crocodiles (Crocodylus porosus) and to improve understanding of their habitat ecology,” said a senior official of the Sundarban Tiger Reserve (STR).

Saltwater crocodiles, being apex predators, are considered key indicators of the health of the aquatic ecosystem. The study recorded direct and indirect sightings of crocodiles, along with data on salinity, surface water and ambient temperature, creek widths, slope of banks and vegetation.

The survey was carried out over three months, with three days of fieldwork in each month, covering the entire 1,168 km transect length of the Sunderbans. Survey dates were aligned with the neap phase of the moon and forecasted temperature ranges. The team recorded 213 direct sightings across the Sundarban Biosphere Reserve (SBR). Findings suggest that crocodiles prefer high-tide creek widths between 10 and 130 metres, with a median of 90 metres.

They also favour salinity levels between 10-23 parts per thousand and basking temperatures of 20-30 degree C during winter.

“It is recommended that the assessment exercise continue for the next two years to study population trends, dynamics, and nesting sites,” said a Forest department official. The new estimates mark a steady rise in crocodile numbers.