Supporting the management and sustainable use of marine biodiversity in Honduras    
 

   
Mangroves
Mangrove roots by Steve Canty
 Mangrove ecosystems are one of the most productive ecosystems in the world. They are especially important to the island of Utila, as they comprise approximately 75-80% of the island. There are four species of mangrove on Utila, the red mangrove, Rhizophora mangle, the black mangrove, Avicennia germinans, the white mangrove Laguncularia racemosa, and the button wood mangrove, Conocarpus erectus. The most important species are the red mangrove and the black mangrove. The red mangrove inhabits the land-sea interface, the black mangrove occupies the zone behind.
Mangroves perform important ecosystem services, which benefit both associated environments (coral reefs and seagrass beds) and humans, for example coastal defence, sediment stabilisation, and fish nursery area. Coral reefs adjacent to healthy mangrove stands have 60% more fish biomass than isolated coral reefs.
Utila's mangroves by Sabrina Littee
Mangroves themselves are highly specialised, they are able to tolerate high levels of water salinity, halophytic, some species of mangrove will not fully develop if the water salinity is too low. Although they inhabit salt water they require fresh water to survive, like other plants.
They have specialised root cells which prevents salt uptake and allows them to intake approximately 80-90% fresh water, species dependent. The remaining salt is either held in salt glands within the trunk of the tree or is excreted through the leaves. It is these specialised roots which also allow them to grow and colonise in areas of unconsolidated sediments, the red mangrove has prop root which extend at various angles from the main trunk and provide stability to the tree itself and initiates the binding and stabilisation of sediments. The black mangrove has pneumatophores which are straw like appendages that protrude through the soil from a network of cable roots and allow for further sediment stabilisation. The root networks that are formed by various individual trees intertwine and produce an intricate three-dimensional lattice, which support algal and invertebrate communities adding to the biodiversity and productivity of the area.
 
 
Utila Centre for Marine Ecology, East Harbour, Utila, Honduras | | +5044253026