Black Mangroves a miracle at work

The National Trust protects 2,400 acres of dry forests and mangrove wetland for the Cayman Islands.

Black Mangroves

Black Mangrove – Avicennia germinans

Approximately 1,500 acres of the Central Mangrove Wetland is protected through the Marine Parks Law, forming part of the Environmental Zone which has been in effect for Little Sound and its fringing mangroves since 1986.

Efforts are now under way to increase the area of the Wetland under protection, through conservation land purchase.

The following is taken from Wild Trees in the Cayman Islands by Fred Burton, with illustrations by Penny Clifford; Photographs by Frank Roulstone and Marnie Laing.

Black Mangrove

Avicennia germinans

Black Mangrove is named for the dark growth of algae which coats the trunk.

This appears black when wet, in strong contrast to the grayish green leaves which can appear quite pale.

Black Mangrove can grow in extremely salty conditions: the trees absorb salt along with water through their roots, but then get rid of it again by exuding the salt out of their leaves! On the leaf surface, the salt tends to absorb atmospheric moisture, so often becoming wet.

When it rains the salt washes back into the ground again.

The bark is rough, cracking, shallowly into small, irregular squares, but it appears even textured from a distance. The trunks of mature trees are usually fairly straight, branching into broad crowns.

They are frequently hollow and so make suitable nesting cavities for parrots.

Black Mangroves often grow over large areas, in wetlands which are too salty for any other tree to survive.

The ground around the trees is carpeted with thousands of finger-like breathing roots, known as pneumatophores, projecting up form the ground above the highest flood level.

The trees flower in early summer, producing white, nectar rich blooms which attract bees and so produce a characteristic honey.

The large, bean-like seeds are germinating as they fall from the tree, and must fall on damp mud and root rapidly if they are to survive. Caterpillars of the Caribbean Buckeye butterfly feed on the leaves of young seedlings.

Black Mangrove is common throughout mangrove wetlands on Grand Cayman and Little Cayman, and a few small specimens grow near the westerly ponds on Cayman Brac. It occurs throughout the tropical and subtropical Americas, and also on the west coast of Africa.

Grow Cayman Plants and encourage Cayman Wildlife!

For more information, to share your knowledge or if you would like to get involved with the many activities in the National Trust’s Know Your Islands Program, please visit, or call 949-0121.

Last week’s answer: Governor Gore Sanctuary is located off Spotts Newlands Road on Pennsylvania Avenue.

Trivia question: How is ‘daub’ made for the construction of traditional Caymanian homes?

Look for the answer in next week’s feature!