1. Mangrove Ecosystems

2. What are Mangroves? Mangroves are plants that grow in tidal areas.
The word mangrove can describe a single plant or it can refer to a whole community of plants .
They are halophytes (‘salt loving”). Most plants can not survive in salty conditions.

3. Where Do Mangroves Grow
Where Do Mangroves Grow? Look at the Map Showing the World Distribution of Mangroves? Is There Anything That You Could Infer About Mangroves by Looking at the Map?

4. Where do Mangroves Grow?
Mangroves grow only in the tropics and subtropics. They do not tolerate cold temperatures well, and freezing temperatures will kill them.
Picture of mangroves in Sarasota Bay. K Broderick

5. Where do mangroves grow?
Mangroves grow best in sheltered areas with low wave energies. High wave energies destroy the shallow root systems of Mangroves. They also prevent seedling establishment and the build up of fine sediments needed for growth.
Picture of Longboat Key Mangroves, Florida. K. Broderick

6. Stop and think!
What impact do you think that hurricanes might have on a Mangrove community?

7. Effect of hurricanes
Hurricanes have a profound impact on Mangrove communities. Severe erosion and wind damage can severely restrict growth. In severe cases areas of mangroves can be destroyed. The picture shows damage to Florida mangroves by Hurricane Charley.
Picture courtesy of USWF

8. Did you know?
There are about 100 types of mangrove plant around the world. This includes some palms and ferns.
In Florida there are four main mangrove plants.
There are approximately 47,000 acres of mangrove in Florida.

9. Types of mangrove in Florida
Florida mangroves include 4 tree species.
The Red mangrove
The Black mangrove
The White mangrove
The Buttonwood
Each mangrove has its own level of salt tolerance and this determines its location.

10. The Red Mangrove
Tall arching roots called prop roots. These supply air to the underlying roots and provide stability.
Found closest to the water as they have the highest salt tolerance.
Dark green elliptical leaves, which are paler underneath.

11. Red Mangroves
The pictures show the flowers of the red mangrove and also its leaves, seeds and developing prop roots. Notice that the prop root develops from the seed and grows downward.

12. Black Mangroves Black/brown bark
Numerous breathing tubes called pneumatophores project from the soil beneath.
Grows on high tide shores.

13. White Mangroves
White mangroves are usually found upland of the red and black mangroves. The bark is pale and they do not have prop roots or pneumatophores.

14. Buttonwoods
Buttonwoods occupy the same zone as white mangroves.

15. Mangrove Adaptations
All mangrove plants have special adaptations that allow them to survive in their salty environment.
Their unusual root systems give them support and stability in the loose soil.
There is little oxygen present in these soils and prop roots and pneumatophores allow them to get oxygen from the air.

16. Mangrove adaptations
Did you know that mangrove plants are unique in that they have live young (viviparous). The seed remains attached to the parents plant until it germinates. It then falls from the tree and drifts on the water until it finds somewhere to take root.
Red mangrove fruits courtesy of Selby Gardens

17. Mangrove adaptations
Mangroves do not have to live in salt water. They tolerate the salt water and so out-compete other plants. They excrete salt through pores in their roots and leaves.

18. Why are mangroves important?
Mangrove plants form a unique ecosystem.
An ecosystem consists of living organisms and non-living factors such as soil and water.
Mangroves are essential to the first link in the food chain. When their leaves fall into the water and are decomposed by bacteria many valuable nutrients are released that are essential to the growth of plankton. Plankton are the producers in this and oceanic ecosystems.

19. Why are mangroves important?
The leaf detritus also provides food for animals such as worms, snails,mussels, oysters,shrimp, clams and mullet.

20. The Mangrove Ecosystem
These detritus eating animals are a source of food for carnivores such as crabs and fish . These in turn provide food for larger fish, reptiles and birds.
Picture – Mangrove Crab

21. The Mangrove Ecosystem
Mangrove wetlands provide habitat, feeding, breeding and nursery areas for a wide variety of plants and animals, including endangered species.
Picture shows a Snowy Egret

22. Wildlife in the Florida mangroves Pictures from left to right horseshoe crab, sheepshead, tree snail, mangrove water snake.

23. Mangrove wildlife pictures show from left to right: blue crab, blue heron, fiddler crab, mangrove snapper

24. Mangrove wildlife From left to right Florida fighting conch, mangrove buckeye, periwinkle,American crocodile

25. Habitat
The roots of the mangrove provide shelter for many fish and other animals. They also provide an attachment site for many creatures such as sponges and anemones. In addition the trees themselves provide nesting site for many birds.
Picture shows a Snook.

26. Habitat
Other creatures such as bats, snakes, insects and frogs also live in mangrove habitats.
Picture shows a Mangrove Cuckoo

27. Breeding Grounds
Mangroves are an important breeding ground for many animals, including fish and birds.
Picture shows a roseate spoonbill

28. Nursery
The mangroves serve as a nursery to many animals, such as mollusks, crustaceans, and fish. The picture shows a juvenile Tarpon.

29. Feeding grounds
Mangroves are a vital source of food to many animals . Some live in the mangroves permanently, some only part of their lives and some just come to visit.
Picture shows a young Lemon Shark courtesy of J.Stafford-Deitsch- Shark Foundation

30. Endangered Species
Florida mangroves support a number of endangered species such as
The west Indian manatee
The brown pelican
The eastern indigo snake
The hawksbill turtle

31. Besides being an extremely productive ecosystem mangroves also……..
Act as a buffer against the high winds and eroding waves of storms.
The mangroves trap sediments and prevent them from building up further out to sea, which is damaging to other ecosystems like coral reefs and sea grasses.

32. Amazing mangroves
Did you know that mangroves can filter out pollutants like nitrates, phosphates and petroleum based products that are present in run-off? The microbes in the sediment break the pollutants down.

33. Fisheries
Mangroves contribute to our economy;they have a big influence on our fisheries, because so many commercially fished species breed or develop there. The mangroves also provide an important source of food for other marine life.
Picture shows Florida Stone crab

34. Food for thought …
If mangroves were removed what impacts would this have? How many can you think of?

35. Man and mangroves
Mangrove communities have been significantly reduced as coastal areas have become more developed. This is especially true in Florida. The picture shows development encroaching on an area of mangroves.

36. Man and Mangroves
Dredging floods mangroves. This submerges their air breathing roots and they can not get enough oxygen and nutrients.
Picture courtesy Army Corps of Engineers

37. Pollution
Although mangroves filter some pollutants, they can be irreparably damaged by oil spills and herbicides in particular.
Picture shows Mangrove clean up after an oil spill, picture courtesy of NOAA.

38. Mangrove conservation in Florida
The Mangrove trimming and preservation act is a piece of legislation which protects Florida mangroves. It regulates the trimming and alteration of mangroves and bans the use of herbicides and other chemicals to defoliate mangroves.

39. Mangrove conservation in Florida
Mangroves can reestablish in years if conditions are right. This can be achieved by planting mangrove seedlings.

40. Mangroves around the world
It is estimated that the world has lost 20% of its mangrove forests since 1980.
This could have alarming effects on biodiversity, due to loss of habitat.
It could also result in the silting of coral reefs, shipping lanes and ports.
Picture shows mangroves destroyed by pollution. Photo credit T.Wilke

41. Mangroves around the world
Loss of mangroves could also severely impact economies that rely on tourism and fisheries.
Without a barrier of mangroves low lying countries such as Bangladesh, are more susceptible to flooding and devastation by cyclones. The dark areas in the satellite image show mangrove areas in Bangladesh.
Picture courtesy of NASA

42. Present status of Mangroves
Although mangroves are decreasing the rate is slowing down as more countries pass laws to protect them. More projects to replant mangroves are underway around the world, but there is still along way to go before this ecosystem is protected.

43. Bibliography
Environmental Protection Agency, (2006). Mangrove swamps. Retrieved August 5, 2008, from Wetlands Web site:
U.S Fish and Wildlife Service, Hurricane Charley. Retrieved August 5, 2008, from J.N. Ding Darling wildlife refuge Web site:
Lee County government, Mangroves. Retrieved August 5, 2008, from Community development
Newfound Harbor Marine Institute, (1998). Ecology. Retrieved August 2, 2008, from Mangroves Web site:
(2007). International society for mangrove ecosystems. Retrieved August 5, 2008, from ISME Web site:

44. Bibliography
(2006). Facts about mangroves in Florida. Retrieved August 5, 2008, from Florida department of environmental protection Web site:
Importance of mangroves. Retrieved August 5, 2008, from Florida Museum of natural History Web site:
Riley, Robert W. (2001). Ecological importance. Retrieved August 5, 2008, from Mangrove.org Web site: