The appearance of mangroves is no clue to the important role they play in the ecosystem. Often thought of as a nuisance or as a useless swamp, the mangrove ecosystem is undeniably vital to the coastal zone. Among the reasons, mangroves act as a nursery area for many fish species, absorb potentially damaging wave and storm energy as well as acting as a reservoir pollutants.

The term mangrove actually refers to approximately 69 species of woody plant that live in tidal swept areas that mix fresh and slat water. They are generally found in tropical areas where the water temperature exceeds 24 C / 75 F.

These plants are remarkable for their tolerance to varying salinity, water temperature and nutrient concentration. This resilience is fortunate as the plants were, until fairly recently, considered a nuisance and removed in many cases.

The plants themselves are instrumental in forming a nursery ground for many aquatic species. In addition to finding a place to hide among the convoluted root structure, many young live there for the readily available food source. Mangroves naturally deposit leaves and bark in the water, which is broken down by bacteria and fungi. The nutrients are then recycled through the ecosystem as invertebrates capitalize on the available food. This then supports slightly larger organism such as small fish and shrimp and so on up the food chain.

The root system forms a basic structure for the plant. Because they grow mostly in sort sediment with low oxygen content, the root structure is fairly significant and above ground.

This also allows for sediment accumulation in and around the root structure, which can form a protective barrier against extreme weather. Mangroves are also natural pollution filters through a process called rhizofiltration. This is absorption of pollutants from surrounding water into the mangrove roots. Since the area around mangrove root is aerobic, it allows microorganism that can break down these pollutants to flourish. This capability is, however, finite and can be overwhelmed. Although mangroves were once considered a liability and of little importance, it is clear that they are vital to the health of coastal areas.

The Bali Barat National Park is home to approximately 19 different species of mangrove. Some of them live along the coastal area of Banyuwedang bay where Mimpi Resort is located. Others occupy coastal areas along Gilimanuk and Terima bay, Prapat Agung peninsula and Menjangan island. They are generally well protected and healthy and serve as a distinctive habitat for several rare aquatic species.