Department of Parks adn Wildlife

What is a mangrove? Mangroves are amazing trees that have managed to adapt to growing in the inhospitable tidal zone between the land and the sea. Mangroves are recognised by their pencil-like breathing roots that arise from the tree's radially spreading roots.

Why are they important? Mangroves from spectacular coastal forests that provide valuable nursery areas for juvenile fish and crustaceans and are an important source of nutrients for the adjacent marine ecosystem. Turtles, particularly young ones, use these areas for shelter and food. The mudflats are rich in burrowing invertebrates and are important feeding areas for significant and internationally protected migratory wading birds. Mangroves also help to protect the coastline of the Kimberley and Pilbara regions from serious erosion during tropical cyclones.

Shovelnose shark in mangroves - Vision courtesy of MIRG Australia ( Office Productions

What do they look like? There are several species of mangroves but the white mangrove (Avicennia marina) is the most widespread. These smooth-barked trees have clusters of small fragrant orange flowers. They often bear the brunt of ferocious cyclones in the wet season, but regenerate rapidly afterwards. This tree usually grows up to five metres high. It has greyish-white bark with some flaking patches. The leaves are dark glossy green on their upper surface and grey to silvery below. The grey mangrove is laden with fruits from December to May.

Where do they grow? Mangroves inhabit tidal areas, growing on the seaward and landward edges of mangrove areas. The Montebello Islands Marine Park is an especially important area for mangroves, as six species of mangroves occur in this marine park, usually in narrow strips fringing bays. New parks created under the State Government's Kimberley Science and Conservation Strategy that protect important mangrove habitat include the Eighty Mile Beach and Lalang-garram / Camden Sound marine parks. Several more areas that are being considered for new marine parks, including the proposed Roebuck Bay, Lalang-garram / Horizontal Falls and the North Kimberley marine parks, include mangrove habitats of major regional importance.

Grey-tailed tattlers near mangroves - Vision courtesy of MIRG Australia ( Office Productions

Interesting facts: The white mangrove produces the only mangrove fruits eaten by Aboriginal people. However, the toxins are first removed by soaking them in mangrove mud for three to seven days until they turn black. They are then rinsed and boiled twice or roasted until the skin and black colour is gone. The branches are used for shades and are burnt to repel sandflies. Native beehives are found in hollows. The foliage is sometimes heavily grazed by cattle, possibly because of the salt on the leaves. The flowers produce excellent honey.

Protecting mangrove forests: One of the best ways to preserve Western Australia's biologically important mangrove forests is to consider their protection within marine parks. New marine parks being considered along the Kimberley coastline should help to protect many of Western Australia's most important and diverse mangrove areas, along with their dependent plants and animals.