Which one of the following states launched is February 2015 a “dolphin Census” in the coastal eco-system and shorelines of state?

The correct answer is D (Odisha). In February 2015 the Odisha Forest Department began a dolphin census covering the coastal ecosystem and shoreline, with Chilika lagoon and the adjoining sea as key habitats for the Irrawaddy dolphin. Odisha's coast also has Bhitarkanika, so the state had a strong reason to survey its marine mammals.

The core concept is the distinction between river and coastal cetaceans and the protected status they share.

• Gujarat (A): Its dolphin interest centres on the Gulf of Kutch and Gulf of Khambhat, and it is not the state tied to this 2015 census.
• Karnataka (B): Known for the Gangavali river and Kali estuary dolphins, not this coastal census.
• West Bengal (C): Associated with the Gangetic dolphin in the Hooghly and Ganga system, which is a river population.

For Mains, the Gangetic dolphin was declared the National Aquatic Animal in 2009, and both river and marine dolphins are listed in Schedule I of the Wildlife (Protection) Act, 1972. This links to biodiversity conservation and the wider debate on coastal ecosystem protection.

Trap: candidates mix up the Gangetic dolphin states with coastal dolphin surveys and pick West Bengal or Gujarat by association. Check whether the question is about a river population or a coastal one.