Residents of Ghoramara Island want to leave their home as it shrinks each year due to rising seas, but many say they can't afford it. The 4.6 sq km (1.8 sq mile) island, part of the Sundarbans delta on the Bay of Bengal, has nearly halved in size over the past two decades, according to village elders. The tiny island is home to 4,800 people, down from 7,000 a decade ago. "If a tsunami or a big cyclone hits this island we will be finished," said Sanjib Sagar, village leader on the island 150 km (93 miles) south of the Indian city of Kolkata. The Sundarbans, shared by India and Bangladesh, include the world's largest mangrove forest as well as rare or endangered tigers, dolphins, birds and reptiles. Ghoramara is among many islands in the delta affected by rising sea levels and soil erosion experts say is caused by climate change. Residents say the flood waters are getting worse, threatening their homes and livelihoods.