Nha Trang Bay

Nha Trang Bay is located in the eastern coastal area of Nha Trang, Khanh Hoa Province, with geographical coordinates from 12°8'33"N to 12°25'18"N and 109°7'16"E to 109°14'30"E. The bay borders Nha Phu Lagoon to the north, Vietnam's territorial waters to the east, the northern gateway of Cam Ranh Bay to the south, and the coastline from Ke Ga Cape to Cu Hin Cape to the west. The total area of the bay is 24,965 hectares, including 19 islands, the largest being Hon Tre (3,250 ha) and the smallest being Hon Noc (4 ha).

The bay's climate has two distinct seasons: the dry season from January to August and the rainy season from September to December. The average annual temperature ranges from 14 to 39°C. The Cai River in Nha Trang is the main freshwater source flowing into the bay. The tides are irregular diurnal. Currents and waves are influenced by the northeast and southwest monsoons.

The formation history of the bay spans five stages, from the pre-last glacial maximum transgression to the post-Flandrian regression. The seabed topography is divided into three dynamic zones and nine geomorphological units. Sediments include both ancient and modern types, with eight types of surface sediments. Light minerals dominate, while heavy minerals comprise about 20 types.

Nha Trang Bay is considered one of the rare natural models of bay systems in the world, containing most of the typical ecosystems of tropical seas. Coral reefs are the most representative ecosystem, with over 350 species of coral (accounting for 40% of the world's reef-building corals), recognized as internationally important and having the highest biodiversity in Vietnam. Mangrove forests are concentrated in Dam Bay with 9 species of mangroves. Seagrass beds have 10 species, accounting for 2/3 of the seagrass species in Vietnam.

Main economic activities include fishing, aquaculture, and tourism. Tourism is a priority, with about 5 million visitors each year. Notable tourist attractions include Hon Mun (snorkeling to see coral), Hon Noi (the only double beach in Vietnam), Hon Mieu (Tri Nguyen Aquarium), Hon Chong, Hon Do, and the Vinpearl Land cable car, which was once the longest sea-crossing cable car in the world.

Nha Trang Bay faces environmental issues such as declining water quality and coral reef area. From 1994 to 2005, average coral cover decreased by 31.2%. Causes include destructive fishing, pollution, outbreaks of crown-of-thorns starfish, and climate change. The Nha Trang Bay Marine Protected Area was established in 2001, covering over 16,000 hectares, to protect and restore the ecosystems.