Status (IUCN): Least concern. However, mangrove forests are considered highly significant ecological communities and are overall in decline in many areas due to localised threats and climate change.

Characteristics

• Height:  Up to 35 m high.
• Roots: Knee roots that grow up to 60 cm vertically and emerge from the underground root system. They can grow within a radius of 10 m around the tree. These knee roots are covered in lenticels (air pores) that assist with gas exchange.  Some trees may also have stilt roots.
• Trunk: Dense, erect and bark is rough and dark brown, dark gray to black. It can reach a diameter of 20 – 40 cm.
• Leaf Identification:  Elliptic, pointed, arranged opposite one another on the stems, 12 – 25 cm long, 3 – 9 cm wide.  thick, glossy and glabrous. Arranged opposite to one another on the stems and can have three or four leaves formed simultaneously.
• Leaf Colour: Smooth and dark green on the upper side and waxy and light green on the reverse side; no glands for excreting excess salt.
• Flowers: Colours vary from light orange to dark pink and dark red. They are 3 – 5 cm long. They are axillary flowers and grow at the end of each branch.
• Fruits and seeds: The seeds (propagules) are the fruit. They are 20 -25 cm long on average and the colour varies from greenish to burgundy when ripe. They grow within the flower’s calyx tube and are held by the flower, hanging vertically from the tree branches.

Reproduction: Bisexual flowers appear from late winter to summer. As a viviparous species, the seeds (propagules) grow vertically. Once fully developed, they fall from the tree darting into the ground, allowing for quick establishment once they settle. If the propagules fall into the water instead of the soil, they disperse from the parent tree by tidal water movement.

Habitat: Intertidal zones with soft muds and sand such as the seashore, wetlands, and the margins of tidal estuaries as well as in black soil outside the intertidal zone on the coast.

Status (IUCN): Least concern. However, mangrove forests are considered highly significant ecological communities and are overall in decline in many areas due to localised threats and climate change.

Characteristics

• Height:  Up to 3 – 5m high in cooler climate but can reach 15 – 30m in the tropics.
• Roots: Stilt or prop roots that arise from the trunk or branches and then grow toward the soil, developing an underground root system. The stilt-like roots are covered in lenticels (air pores) that assist with gas exchange.  They grow vertically and spread out from the trunk, enabling the mangrove roots to breathe in the intertidal zone.
• Trunk: Dense, erect and bark is rough and reddish brown.
• Leaf Identification:  Obovate to elliptic, (broad with a sharp abrupt terminal point),  6–14 cm long, 3–8 cm wide, thick and leathery. Arranged opposite to one another on the stems but leaves also grow in clusters at the end of branches. 
• Leaf Colour: Glossy, smooth dark green on the upper side and waxy, light green to yellowish on the reverse side, with special glands for excreting excess salt. Reverse side is usually spotted with brownish-reddish dots.
• Flowers: White to varying tones of yellow, from pale to dark. In clusters.
• Fruits and seeds: Brown and 3-5 cm small. Ovoid to pear-shaped. The seeds (propagules) start to grow their sprouts in the fruit, vertically.

Reproduction: Bisexual flowers may appear most of the year but occur predominantly in the winter. As a viviparous species, the seeds (propagules) partially germinate in the fruits while still attached to the tree, allowing for quick establishment once they settle. Once they are fully grown, they detach from the fruits and dart into the ground, developing the roots soon after.  If the propagules fall into the water instead of the soil, they disperse from the parent tree by tidal water movement.

Habitat: Intertidal zones with soft muddy and sandy soils such as the seashore, wetlands, and the margins of tidal estuaries, creeks and rivers. They occur low in the intertidal zones, and their roots get submerged at high tides. They are usually found with the grey mangrove species.

Status (IUCN): Least concern. However, mangrove forests are considered highly significant ecological communities and are overall in decline in many areas due to localised threats and climate change.

Characteristics

• Height:  Up to 4 m high, mostly shrubs.
• Trunk: It has smooth, grey bark.  Trunk and some branches are covered in lenticels (air pores), which assist with atmospheric gas exchange.
• Roots: Roots develop along the soil surface, exposed to air during low tide so they can uptake oxygen.
• Leaf Identification: Obovate (spoon-shaped with a rounded tip), leaves arranged alternately and in spiral along the stem.
• Leaf Colour: Glossy green on the upper side and paler green on the reverse side, with minute glands for excreting excess salt from the plant.
• Flowers: White and small, in umbellate clusters. The scent is similar to rotten bananas.
• Fruits and seeds: Light green to pink, small, curved, cylindrical and elongated, fleshy.

Reproduction: Bisexual flowers appear more profusely in late spring and summer with minor flowering occurring throughout the year. As a viviparous species, the seeds partially germinate before the fruits fall (propagules), usually between summer and autumn. This allows for quick establishment once they settle. They are dispersed from the parent tree by tidal water movement.

Habitat: Intertidal zones with soft muds and sandy soils such as the seashore, wetlands, and the margins of tidal estuaries, creeks and rivers. Often at the seaward edge of the mangrove zone.

Status (IUCN): Least concern. However, mangrove forests are considered highly significant ecological communities and are overall in decline in many areas due to localised threats and climate change. Grey Mangrove (Avicennia marina) is the most common and widespread mangrove species.

Characteristics

• Height:  2 – 10m high (but can be up to 25m high).
• Trunk: large, the bark is finely fissured and grey. 
• Roots: Spongy, pencil-like roots called pneumatophores, which are specialised root structures that grow vertically and spread out from the trunk, enabling the mangrove roots to breathe in the intertidal zone. The pneumatophores are covered in lenticels (air pores), which assist with atmospheric gas exchange.
• Leaf Identification:  Leathery and narrow-obovate to obovate-lanceolate (generally oval and pointed), arranged opposite one another on the stems. It can be up to 8 cm long and 5cm wide.
• Leaf Colour: Glossy green on the upper side, and pale grey and slightly hairy on the reverse side, with special glands for excreting excess salt.
• Flowers: Yellow or orange, in small dense clusters.
• Fruits and seeds: The fruits are almond sized, pale green and hairy, 2 cm long and 3 cm wide. They are compressed ovoid capsules covered by the pericarp, and each fruit holds a single seed.

Reproduction: Bisexual flowers appear in mid-late summer through early autumn. The fruits mature after two months, ripening in the summer. As a viviparous species, the seeds (propagules) partially germinate inside the fruit while still attached to the tree, allowing for quick establishment once they settle in a location with ideal conditions, either close to the parent tree in muddy/sandy soil or dispersed by tidal water movement. Seedlings can stay small and survive with just a few leaves for many years. They wait for an opening in the canopy such as from the fall of an old tree to then develop into a tree.

Habitat: Intertidal zones with soft, muddy and sandy soils (but not on pure mud) such as the seashore, wetlands, and the margins of tidal estuaries, creeks and rivers. It may grow with river, red and other mangrove species. As a pioneer species, it colonises an area and develops mud banks.

Threats
• Coastal development, which includes building roads, bridges, canals and marinas
• Poor water quality due to run-off from land clearing, overgrazing and agriculture
• Ports, dredging and any activity that physically damages seagrass or interferes with the conditions around seagrass meadows
• Boating, boat anchors and trampling
• Overfishing
• Pollution and accidental spills
• Climate change
• Human use

Ways You Can Help Seagrass Meadows
• Reducing your carbon footprint
• Buying sustainable and responsibly sourced seafood
• Joining coast care groups in your area
• Working to improve water quality
• Establishing and maintaining buffer zones between coastal habitats and urban developments in their proximities
• Prioritising the protection of areas where mangrove and other coastal habitats are likely to retreat with sea level rise
• Fencing along the intertidal zone to prevent access of livestock
• Creating protected areas of seagrass
• Reducing overfishing

Learn About The Different Seagrass Species

Threats

• Coastal development, which includes building roads, bridges, canals and marinas
• Coastal erosion affecting shorelines, estuaries and lakes
• Poor water quality due to run-off from land clearing, overgrazing and agriculture
• Pollution and accidental spills
• Climate change
• Human use

Ways You Can Help Mangroves

• Reducing your carbon footprint
• Buying sustainable and responsibly sourced seafood
• Joining coast care groups in your area
• Establishing and maintaining buffer zones between coastal habitats and urban developments in their proximities
• Prioritising the protection of areas where mangrove and other coastal habitats are likely to retreat with sea level rise
• Fencing along the intertidal zone to prevent access of livestock

Learn About The Different Mangrove Species