Bio-diversity value


       According to the scientists, Ha Long Bay owns a high bio-diversity with the typical ecosystems of the tropical sea. The bio-diversity in Ha Long Bay is shown by the variety of species, and endemic and rare genes
     According to a research of the Resources and Sea Environment Institution, which has been undertaken in 2008, in Ha Long Bay, there are 2,949 species of fauna and flora of which 1,259 inland species, 1,553 water species, 66 species of reptile and amphibian and 71 bird species. Scientists identified 102 specious and rare species at universal and/or regional level, of which 17 plants are endemic to Ha Long Bay. This is a natural area of Vietnam where the most numerous species have been found. List of species can be found in the following table:

     There are 10 kinds of typical eco-systems in Ha Long Bay. However, it can be divided into two main different categories, namely: the tropical forest ecosystem and the seashore ecosystem.
     *The tropical forest ecosystem:
     The total number of plant species living on the rugged islands in Ha Long Bay is 507 species, 351genus of 110 familias of kormobionta, of which 486 species of magnoliophyta, 14 species of polypodiophyta, 2 species of lycopodiophyta, 1 species of psilophyta, and 2 species of gymnospermatophyta (pinophyta). It also lists a total of 66 species of reptile and amphibious, 71 species of bird, and 22 species of animal.
    Several different communities (species of plants that always grow together) are found, such as: mangrove, seashore plants, those of the slopes or sheer cliffs, the summit plants, and those that grow around the mouth of caves and grottoes. These plant species have adapted to live on the limestone islands in Ha Long Bay. Until now, 17 endemic plants have been found on Ha Long Bay. Their names are listed in the following table:

     *The marine and sea-shore ecosystem: (including the wet land and marine ecosystem)
     To date, in Ha Long Bay, the scientists have found out 571 benthos, 419 species of plankton, 181 species of coral, 156 species of marine fish, 139 species of algae, 5 species of sea-grass, and 19 plant species in mangroves.
     + The wet land eco-system: The wet land eco-system of Ha Long Bay and its surrounding area can be divided into 7 main eco-systems:
     - Mangrove eco-system: There are 19 species of plants in mangroves of Ha Long Bay.


     Mangroves in Ha Long play an important role as they provide a home to nearly 500 species of creatures, of which 306 zooplankton, 90 species of marine fish, 16 species of algae, 12 species of mammal, 5 species of of reptile, and 4 species of sea-grass.
     -  Sea-grass ecosystem.
     It is comprised of only 5 species of sea-grass but it offers the habitat for 17 species of algae, 14 species of benthos, and many other marine creatures. It also has the advantages of preventing the creation of waves and cleaning the water environment by absorbing organic waste.


     Rock-reef littoral ecosystem around limestone islands in Ha Long Bay
     This ecosystem is found at tidal cliff on the foot of the islands on Ha Long Bay. It is a home to 423 species of which 129 species of algae, 12 species of coral, 51 species of polychaeta (sand worms), 60 species of snails, 75 species of mollusk, 70 species of crustacea, 12 species of echinoderm, 2 species of sponge, 2 species of reptile (sea snake and varan), 21 species of sea birds, and 3 species of otter.
     Sand beach circumlittoral ecosystem in coastal islands
      These are protective sand beaches along coastal islands with coral reefs underneath. They are the home to 116 species of which 32 species of polychaeta, 22 species of mollusk, 31 species of snails, 24 species of crustacea, and 4 species of echinoderm.
     Soft bottom ecosystem in low tidal flats in estuaries
     These are tidal flats connected with mangroves and sand dunes emerging at estuaries. They provide home to 145 species of phytoplankton; 54 species of zooplankton, 150 species of benthos; 58 species of algae; 5 species of sea-grass; 79 species of marine fish.

     Coral reef ecosystem 


     This ecosystem stretches from the southeast of Cat Ba island to the islands in the south of Ha Long Bay. The coral reefs here mostly feature fringe lagoons, reef flats - both inside and outside, crest, slope and platform reefs. To date, it is estimated that in Ha Long Bay there are 231 species of coral belonging to 4 classes. Of which hard coral class comprises 204 species. The coral reefs in Ha Long Bay are the home of 230 species of mollusk, 180 species of phytoplankton, 155 species of marine fish, 129 species of   algae, 118 species of annelida, 104 species of zooplankton, 77 species of crustacea; 15 species of echinoderm; 11 species of sponge. This ecosystem has a high biological capacity and a water cleansing ability.
     “Tung” and “Ang” (lagoon) ecosystem: This is a special ecosystem of Ha Long Bay. Karst lagoons are created by geological tectonic movement. These are lakes lying within the islands with narrow entrances to the sea. These favorable conditions create this special ecosystem and beautiful landscape of Ha Long Bay.


     At present, in Ha Long Bay it is estimated that there are 62 “Ang” and 57 “Tung”. This ecosystem refers to the reservoirs of rare and specious genes of Ha Long Bay. It is the home to over 72 species of fauna and flora of which 21 species of algae, 37 species of mollusk, 8 species of crustacea, 6 species of echinoderm, and some other species of coral.

     + Aquatic ecosystem
     This marine ecosystem includes phytoplankton, zooplankton, zoo-benthos and nekton.
     - Phytoplankton
     These are small animals drifting in the water. They can autotrophy through the process of photosynthesis. They are the first link in the nutrient chain, which create the basic capacity of Ha Long Bay. They contribute to the dissolution of organic matter and thus help against water pollution. According to the results of site surveys in 2008, there are 278 species of phytoplankton in Ha Long Bay, 64 of which are algae.
   - Zooplankton
    These too are small animals drifting about in the water. They are the second link in the nutrient chain (next to the phytoplankton). The composition of Zooplankton is dependent on water layers and the seasons. It is estimated that there are 141 species of zooplankton in the Ha Long.
    - Zoo-benthos
    These creatures live on the bottom of the sea and have very high nutritional value. Surveys showed that in Ha Long there are 571 zoo-benthos species of 5 main groups, namely: mollusk (261 species) polycheata (145 species), crustacea (113 species); echinoderm (26 species), and sponge (26 species).
     - Nekton
     These animals can swim in the water by themselves and migrate to look for food. They breed or shelter in winter in areas with the depth of around 0 to 20 m. It is estimated that there are 196 species of marine fish. 3 species of dolphin are only found in offshore areas.