THE TROPICAL RAINFOREST
The Main Ridge
"Did also in pursuance of your said Instructions remove to
Your Majesty a tract of Wood Land lying in the interior and
most hilly parts of this island for the purpose of attracting
frequent Showers of Rain upon which the Fertility of
Lands in these Climates doth entirely depend.
Assented to by his Honour the Commander in Chief this
Thirteenth day of April One Thousand Seven Hundred and
The Tropical Rainforest of Tobago:
The Main Ridge
Graham Wellfare and Hema Singh
A project by Environment Tobago
in collaboration with
BP Trinidad and Tobago
Table of Contents
Chapter 1: What is a rainforest?................................................................1
Chapter 2: Where are rainforests found?...................................................3
Chapter 3: The Structure of Tobago’s Rainforest……………………….4
Chapter 4: The History of Tobago’s Rainforest………………………...8
Chapter 5: Why are rainforests so important?.........................................11
Functions and Services provided by Tobago’s Rainforest
Chapter 6: Biodiversity- The key to the rain forest survival…………..15
Chapter 7: Relationships in the Rainforest……………………………..19
Chapter 8: Plant Life on Trees…………………………………………22
Chapter 9: Nutrient Recycling in the Rainforest……………………….24
Chapter 10: Threats To Our Rainforest………………………………...26
Chapter 11: Climate Change and Our Rainforests……………………..29
There are some things that define us in this small island of Tobago and one of
them is our rain forest. This is part of our heritage, legally protected from
human degradation and passed on from generation to generation since 1776,
with each generation holding it in trust and passing it on, hopefully in prime
condition to the next one.
This is indeed an awesome responsibility and is no more the responsibility of
the Division of Agriculture, Marine Resources and the Environment or of
Environment Tobago than it is yours and mine. We all have to feel ownership of
it and take care of it in the same way as we take care of any other personal
possession that we treasure.
But before we can take care of it appropriately, we need to understand it and
feel pride in it as the national treasure that it is. It is in this area of educating
the public about our rain forest that Environment Tobago has stepped forward
in collaboration with BPTT and taken on the educating of people as their
responsibility. They have indeed done a marvelous job and are to be
This book will be useful to students and teachers in schools and other
institutions. It will be useful to persons interested in the natural history of
Tobago and the region as well as to the visitor to Tobago. It is well set out and
extremely reader friendly with numerous illustrations and reading it will
provide a pleasurable experience for all.
Mrs. Claudette Allard
Chief Education Coordinator
Division of Education, Youth Affairs and Sport,
Tobago House of Assembly
The first time I reviewed a draft of this book “Tropical Rainforest of Tobago-the
Main Ridge”- the potential for addressing information gaps and changing the
mindset of our citizens to conservation and stewardship was made starkly
obvious. Finally, the book has been completed, with thanks to its authors. The
importance of this book cannot be underestimated.
This Ecosystem- the oldest “reserve” in the western hemisphere- having been
so declared in 1765; is just a small part of the Rainforests world-wide situated
north and south of the Equator in a narrow belt. Most of them are under threat
from one source or another. In T&T, our forests have disappeared at a rate of
0.8% per year and between 1990- 2000, 2% have been removed.
Tobago’s Main Ridge forest reserve is 3956 hectares in size. It houses a vast
variety of biodiversity; it is ecologically healthy, biologically diverse and
contributes to our well-being. It provides watershed protection, soil protection,
erosion control, landscape beauty, disaster risk reduction, carbon
sequestration, climate regulation, water for all of our uses- domestic and
commercial, and recreational and eco-tourism services.
Yet, we have threats to this wonder of nature from, forest fires (man-made),
Illegal logging, quarrying, squatting, invasive alien species (bamboo),
unsustainable extraction of plants and animals and climate change impacts.
Despite these threats, we offer this book as a way of drawing attention to the
environmental issues affecting the rain forests locally, nationally and globally.
A greater awareness of the links between this forest and our well-being will be
fostered, and our population will learn to steward and support its growth in a
sustainable manner, taking ownership of this, our greatest natural treasure.
Mrs. Patricia Turpin
What is a Rainforest?
A rainforest is “a tree covered area in warmer regions of the world where
rainfall averages over 200 cm per year, allowing for year round growth”
The Green Encyclopedia.
This rather brief, dull description of a rainforest doesn’t do justice to
these wondrous places.
When you think of what a rainforest is what comes to mind? Heat,
humidity, noise, smells, danger, beauty, trees, rain,
biodiversity, deforestation, birds, snakes…..the list is almost endless.
This is truly what a rainforest is.
This booklet gives you an introduction to the wonders of the rainforest
and why they are so important to our future. By
focusing on Tobago’s unique forest reserve this complexity begins to
Rainforests are not just about trees and wildlife, they perform many
functions essential to the earth’s and our own well being. However, they
are still threatened, with repercussions that continue to be disastrous for
everyone. Perhaps if the world looked to Tobago and its rainforest
reserve the true value of this natural resource can be realised.
When is a rain forest not a rain forest?
Other forests exist within the tropics that do not receive enough rainfall
to be considered true rainforests. There is generally a dry season that
limits growth and causes some trees to shed their leaves. These are
known as ‘monsoon forests’, ‘seasonal evergreen forests or ‘deciduous
seasonal forests’. While they perform many of the functions of the
rainforest they do not have the diversity of life.
The forested areas outside of the reserve in Tobago are generally
seasonal evergreen forests while Little Tobago is covered with
deciduous seasonal forest.
Photo: H. Singh
Photo: H. Singh
Where Are Rainforests Found?
Rainforests are found in 3 main areas of the world: South East Asia,
Central Africa and Central and South America. Existing in a narrow
band North and South of the equator and occupying less than 1% of the
earth’s surface, they have the greatest concentration of wildlife of any
The map below indicates where rainforests are naturally found but
much of this has been lost, particularly in South East Asia. Huge tracts
still exist in Amazonia and central Africa but even these are constantly
You might ask yourself why a small place like Tobago has a rainforest
when it is not in any of these regions. Even more remarkable is how
this rainforest is still standing when all around the world deforestation
is so rampant? This is a story of plate tectonics and of a man who had
the vision, over 200 years ago.
Map Showing Major Rainforests of the World
The Structure of Tobago’s Rainforest
Depending on its history and location, rainforests typically have 4
The emergent layer where the giants of the forest occur. Trees here can
grow in excess of 50m.
The canopy layer this is the area in which the majority of trees exist as
well as most of the wildlife as this is where sunlight is most abundant.
The under story layer is the section in which tree ferns, palms and slow
growing trees predominate due to their ability to grow in low levels of
The ground layer is the section in which non woody plants and tree
seedlings occur. Little light penetrates here so growth is sparse.
This rainforest structure is relatively stable as there is little light for
seedlings to take hold. This is known as a climax community. However
as soon as a large tree falls, light becomes available on the forest floor.
Almost immediately this space is filled by herbaceous plants and
climbers. Through the jumble of fallen old growth, pioneer trees make
their way toward the sunlight. In turn, these trees provide shelter for the
emergent trees to grow, and eventually fill the gap.
Because competition for light is so intense pioneer trees have to be quick
growing to prevent themselves from being smothered by other plants. To
achieve this they often have large leaves and lightweight or hollow trunks,
both of which maximize photosynthesis for growth. They also have
slippery trunks and often enlist the help of ants to avoid other plants
taking hold. Pioneer trees provide perfect sheltered conditions for canopy
or emergent trees to grow below them and although they may only last 30
-40 years, they play a vital role in the rainforest structure.
Layers In A Rainforest
The rainforest on the main ridge has been classified as lower montane
This occurs above 250m, where there are no emergent trees because of
exposure to wind. The canopy reaches a height of approximately 30m.
Hurricane Flora has had a great effect on the structure of the forest,
leaving most of the trees no older than 40 years. However, there are
pockets of older trees that escaped the full force of the storm.
The most common canopy tree is the rosewood, while a typical
understory tree is the palm or mountain cabbage.
You will also find the tree fern here, the only living descendent of a
family of trees that died out 290 million years ago.
The ground layer is not typical for a rainforest. as more light has been
available since the hurricane to allow plants to grow.
A common ground The cecropia peltata or
plant is the “coconut- bois canot is one of the
like” Cyclanthaceae. most common pioneer
trees in the reserve.
The Effect of Hurricane Flora:
Near the entrance to the Gilpin trail, the structure of the rainforest can
easily be seen. The slender trees and lush ground vegetation indicate that
forest growth is new. The sheer force of the wind combined with the
enormous volume of rainfall had a disastrous effect at the time. Forty
years later the forest once again looks healthy. Fast-forward a couple of
hundred years and the canopy trees will return while the ground
vegetation will diminish.
The History of Tobago’s Rainforest
Tobago’s rainforest is unique in the Caribbean for two reasons. Firstly,
Tobago used to be connected to South America and so has much of its
flora and fauna. Secondly, the Main Ridge Rainforest has been legally
protected since 1776, making it the oldest protected forest reserve in the
Plate tectonics, or the movement of the earth’s crust, causes continents to
move and mountains to form. Between 225 and 65 million years ago,
land that eventually became Trinidad and Tobago, was much further
west than it is today. This land was periodically connected to mainland
South America, through sea levels falling, allowing for migration of
plants and animals. Sea levels rose and Tobago became an island about
11,000 years ago. Tobago is believed to have been connected to
Venezuela as there are some species that exist here and Northern
Venezuela but not in Trinidad.
For millions of years the rainforest here was undisturbed except for the
odd natural disaster and some small scale hunting by the Caribs and
Arawaks. In the 18th century the British arrived. This was the era of the
sugar trade in Europe. Settlers arrived with land grants from the crown
and began to replace the natural forest with sugarcane. At the same time,
an English scientist Stephen Hales, was researching the circulation of sap
in trees and the relationship between these green plants and the
atmosphere. Results of his research displayed the intimate relationship
between trees and rainfall. If you cut down trees rainfall will decrease.
A friend of Hales, Soame Jenyns, an MP in England, understood the
enormity of this discovery and the importance of having it protected by
law, what is now known as the Main Ridge Forest Reserve.
He suffered strong opposition as many other MP’s were plantation
owners and viewed the forest as timber. Jenyns explained to them that if
the forest was cut down then Tobago would be turned into a desert and
their crops would fail.
After 11 years of persuasion, an act was finally passed on 13th April,
1776 to protect the forest forever.
This story is remarkable and it constitutes what many consider to be the
world’s first environmental act. But it is also a tragedy, this knowledge
has been known for two centuries but deforestation still continues apace
In 1963, hurricane flora swept through Tobago devastating 75% of the
forest. Many of the birds and animals starved as a result -their food
supply had suddenly vanished. But we should not think this was a
tragedy, hurricanes are natural events that cleanse forests of disease. In
the 40 years since hurricane Flora, the rainforest has begun to grow back,
so when you visit the reserve what you see is totally natural. Something
very rare indeed for such a small place.
Map Showing Main Ridge Forest
Tobago’s Main Ridge Forest
“Storms can cause extensive damage in the rainforest
through tree falls. When a canopy or emergent tree
falls, dozens of other neighboring trees, attached by
lianas, are brought down with it. Surveying the forest
following a storm can reveal numerous tree falls, light
gaps, and fallen matter including epiphytes and
branches. However, a healthy forest can recover from
moderate storm damage in a matter of months or years.
The "light gaps" are quickly colonized and soon filled
by canopy trees, while the fallen matter is decomposed
and reabsorbed back in to the system.”
Why Are Rainforests So Important?
Trees create rain through ‘evapotranspiration’. Water that the tree does
not use is transpired through its leaves, evaporating in the heat of the sun.
This will condense to form clouds and eventually fall as rain.
Rainforests account for a large proportion of the worlds flora and fauna
(as much as 50% according to some scientists) yet much of it is still
unrecorded. Locally this diversity can be utilized by harvesting the forest
for food, timber, medicines and many other useful products. If harvested
in a sustainable manner these products could also be traded
Through Photosynthesis the carbon from carbon dioxide in the
atmosphere is fixed or “sequestered” into the plants and trees. This helps
to alleviate global warming.
Rainforests act like a sponge soaking up excess rainwater and allowing it
to percolate slowly through the soil, enabling streams and rivers to run
constantly throughout the year. This provides dependable, good quality
water for millions of people in the tropics.
CONTROL OF SOIL EROSION:
The trees in a rainforest break the impact of heavy rain with its leaves
and roots. A drop of rain can take as long as 40 minutes to reach the
Surface albedo or the ‘shininess’ of the land surface is a basic factor in
controlling climate. Rainforests have thick, green vegetation which
absorbs much of the suns energy limiting the amount of heat reflected
back into the atmosphere and so controlling global warming.
Two hundred years ago Tobago’s rainforest was protected for its rain
creating properties. Since then the many other functions it provides have
been realized. Today, the forest Reserve is considered vital for the
Without it the water supply would be disrupted, crops would fail and
coral reefs would die. Once again, remember that this is a service
provided FREE by the forest. To replace or repair damage caused by
deforestation would be enormous.
Photo: B. Bhikarry
The rainforest provides rain and is the watershed for a large part of the
island. It provides year round, clean household water for most of the
eastern part of the island.
A study done on the Courland catchment area (which provides most of
the western half of the island but is outside the forest reserve) suggests
that due to deforestation and poor agricultural practices. Water supply
has become less predictable and more costly in this area. Run off has
increased in the wet season and water flow has decreased in the dry
season. Soil in the water, ‘turbidity’, causes pumping stations to
malfunction and costly chemicals are used to reduce the effect. Water
shortages could become commonplace in the dry season unless action is
taken like re-forestation of the hills in this area.
Coral reef protection
By controlling soil erosion and allowing year round clear water to flow
into the sea. The rainforest protects many of Tobago’s reefs in the east.
The beautiful reefs at Speyside, Englishman's Bay and Castara are all
dependent on this service. Deforestation would result in increased
turbidity and a change in the salinity of the sea due to flood/drought
regimes in the rivers. Both could have a disastrous effect on the reefs. In
turn the fishing and tourist industries, which are dependent on the reefs,
Tourism is Tobago’s second largest employer and its biggest money
earner. The rainforest plays a key role in attracting visitors to this island
with its beautiful vistas, stunning wildlife and easy access. Many guides
are employed to show visitors these delights. Without it a large sector of
the industry would be lost.
The reserve is too small and inaccessible to provide a timber industry in
Tobago. If timber is to be extracted it should be outside the reserve in
conjunction with agriculture.
Diagram Illustrating the Benefits of a Healthy
Biodiversity– The Key To Rainforest Survival
Biodiversity within a rainforest can be viewed on 2 levels: SPECIES
diversity-the number of different species and GENETIC diversity - the
differences within a species. Of all the earth’s ecosystems rainforests are
the most diverse and productive. Although they cover only 6% of the
land surface they contain over half the estimated 5-10 million plants and
Genetic Diversity- The differences that occur within a species are
vital to its long-term survival. These differences allow for
adaptation to environmental changes – not every individual or
population has the genetic make up to survive change. Habitat
destruction decreases the gene pool and so decreases the chances
of a species survival.
Why are rainforests biologically rich?
1. The tropics, where rainforests exist, have escaped the devastating
effects of ice ages leaving them to evolve undisturbed for millions
2. Most plants here are pollinated by animals and birds (as there is
little wind). The relationship between animals and plants can effect
the evolution of both creating new species in the process.
3. Rainforests are perfect breeding grounds for pests, viruses,
bacteria and fungi. If only a few species were to evolve these would
be quickly targeted and die off.
Awesome statistics abound. A hectare of rainforest in Brazil can contain
500 different species of trees. On one of these trees 400 unique species
might be found. The value of this abundance cannot be over emphasised
both for its aesthetic value and for the services it can provide to people. It
is these products of the forests- the medicines the food and the chemicals
that is one of the keys to their survival.
Biodiversity in Tobago
For such a small island Tobago is fortunate to have a very rich flora and
fauna. This is because it was once joined to the South American
continent and so has remnants of the life from the rainforest there.
Although many of the larger animals have been ‘extirpated’ (become
locally extinct) it still holds an impressive array of life. Tobago is less
rich than its big sister Trinidad but it does have 15 birds, 4 frogs, 1 snake
and 1 lizard that Trinidad does not have.
Tobago’s Flora and Fauna
Tobago’s rainforest remains poorly recorded except for birds and
larger animals. No comprehensive records exist for insects or smaller
animals. The last major survey of trees was in 1943, before the
hurricane and plant records are rare.
It is difficult to specify the number of birds that live in the rainforest
on such a small island, as there is a large overlap of habitats.
Approximately 100 species of bird can be seen of which the following
live exclusively in the reserve.
White tailed sabre-wing hummingbird
Golden olive woodpecker
Great black hawk
Striped breasted spine tail
Blue backed manekin
Cocrico 5 large mammals
White tailed sabre-wing
Red snake or Tobago
Although it is the beauty and bounty of the rainforests that attract us to
them in the first place, it maybe the wealth of the forest products derived
from this diversity that could hold the key to their survival.
The diversity of life in rainforests means that there are more types of
plants to use in industry, more types of fruits and crops that can be grown
for food and more types of plants that can be utilised for their medicinal
purposes. Below are just a few examples of what has been discovered in
All this sounds great but the issue is complicated by the manner in which
these products are exploited and by the political consequences of some
discoveries. For example logging has to be carried out in a sustainable
manner so as not to compromise forest regeneration; property rights need
to be addressed for all countries where rainforest products generate an
income and are a part of community livelihood.
Industry: The sap of the Amazonian copaiba when poured straight into
a fuel tank can power a truck. It is almost identical to diesel.
Agriculture: The dazzling array of fruits and crops from the rainforest
offer varieties of food, that maybe resistant to pests and diseases that
affect modern crops.
Medicine: 70 % of all plants that have been identified as having anti-
cancer properties are exclusive to the rainforest. Only 1%of plants
have been examined!
The rosy periwinkle found in Madagascar gives a 99% chance of
recovery from leukemia
Tobago’s Medicinal Cabinet
Tobago’s rainforest is no different; there are a wealth of plants used
locally for medicinal purposes. However the rainforest plants are poorly
documented - much of the knowledge has been passed down through
generations by word of mouth. A report does exist that lists plants that
need to be researched for their chemical compounds.
This touches on an important issue. Knowledge like this is invaluable but
unless it is written down it could become lost as the culture moves
toward a more western dependency of synthetic medicines.
Some rainforest plants recommended for further
The instantly recognizable dead
cecropia leaf can be boiled and
used as a tea for hypertension
Relationships in the Rainforest
Rainforest ecology is complex. Scientists have barely scratched the
surface of understanding the rainforest's ecological complexities.
Relationships occur between plants, between plants and animals and
between plants and fungi. This is what makes the rainforest work. But it
also makes it vulnerable. By interfering in these processes, particularly
through deforestation, vital links in the ecology can be broken, leaving
the future of the forest in doubt.
The relationship between organisms is called SYMBIOSIS. Three types
of symbiotic relationships occur in rainforests: Mutualism,
Commensalism and Parasitism. These relationships can be mutually
beneficial, benign or destructive. The following pages give examples of
Diagram Showing Types of Relationships Found In Rainforests
(Good for you, good for me)
The agouti and the Brazil
nut: The bertholletia tree in
the Amazon region produces
a nut whose protective pod
is so tough only one animal
can crack it, the agouti. By
producing more nuts than an
agouti can eat in one meal
the nuts become dispersed
by the rodent who buries
them for a later date.
An agouti breaks open a
Ultimately, some nuts are
Brazil nut pod with its forgotten and are left to
powerful jaws. grow into another tree.
Remove the agouti and the
bert hollet ia t ree will
(Good for me, doesn’t bother you)
Flower mites which feed on pollen hitchhike from one flower to
a fresher one by climbing into the nasal passages of
hummingbirds and disembarking when carried to another flower.
Parasitism (Good for me, bad for you)
The leafcutter ant parasitic fly lays its eggs on the backs of leaf-cutter
ants in this way target the porters which carry leaves. The larvae burrow
into the ant’s body after hatching and feed on it until it dies.
Average Lifespan in the wild: several
weeks to several years
Size: 0.08 to 1 inch (2 to 25mm)
Did you know? Ants can lift and carry more
than 3 times their weight!
Plant Life on Trees
One of the remarkable aspects of the rainforest is the variety of plant life
that lives on the trees. This is another form of rainforest relationships.
As so little light gets to the forest floor, plants have had to adapt to
survive using alternative areas within the forest that provide more
exposure to sunlight. This could be on the leaves of trees, the trunks or
even on the plants already using trees as their home.
These plants: lianas (vines or climbers), epiphytes and stranglers play a
vital role in the structure of the rainforest.
Epiphytes are a truly remarkable group of plants. Orchids, ferns and
bromeliads are just a few examples of floor plants that can live on trees.
They have adapted to use every available inch on a tree. A tree in a
pristine rainforest is often unrecognizable because it can be covered by
Epiphytes use trees only for support, this relationship is fairly benign, all
their nutrients come from falling matter-leaves, dead insects or dust.
Orchids and ferns trap this amongst their roots where over time a fine soil
Bromeliads also retain a reservoir of water at the base of their leaves.
When matter falls here, a rich nutritious soup is created.
Stranglers are another remarkable group of plants. They are found only in
rainforests and whereas epiphytes do not harm trees stranglers will
eventually kill their host.
Starting life off as an innocent epiphyte a strangler will often take hold on
a branch of a tree. As time goes by roots are sent down to the nutrients in
the soil below. As the roots grow thicker, they gradually join up around
the host tree and starve it of its nutrients and sunlight (“strangler” might
be a misnomer). Slowly the original tree dies and rots away leaving a
hollow, lattice tree in its place. This is a parasitic relationship.
Vines or climbers
These plants, known as lianas, use the trunk of a tree to reach up toward
the light. As they grow aerial roots are sent down to reach the nutrients in
the soil. These cables that seem to descend from the sky can grow to be
as thick as a mans thigh. Again this is a relatively benign relationship
leaving the host tree unharmed.
Photo: B. Bhikarry
A small bromeliad
beginning its life on a
Above: A strangler tree (the
parrot apple in Tobago) takes a
grip on its host
Left: A common sight in the
forest reserve a cheese plant
moves up a trunk to the light.
Nutrient Recycling in Rainforests
We have discovered that rainforests are home to more species of plants
than anywhere else so surely the soils must be fantastically nutritious.
WRONG! Rainforest soils are surprisingly poor in nutrients. How can
Firstly rainforest soils are typically very old. The rains over the last
millennium have stripped the soils of its soluble nutrients. Secondly, the
nutrients in dead organic matter such as leaves, wood and animals are
very quickly broken down and reabsorbed by the plants. The nutrients
are locked up within the plants. This rapid breakdown occurs because of
the humidity and presence of bacteria, fungi and certain types of animals
(mainly ants and termites). For example a leaf will take about 6 weeks to
decompose in a rainforest while it takes up to a year in a temperate
forest. All this leaves a very thin, typically 2-4 cm layer of fertile soil.
For this reason the roots of trees are very shallow, tapping into the
nutrients at the ground surface with the help of fungal threads.
Because trees are
very shallow rooted
TERMITES AND ANTS
These incredible creatures represent a crucial element in the
rainforest ecology. Studies have shown that these tiny creatures can
make up a quarter of all animal mass here. Termites are the
principal recycler of nutrients from dead wood. Ants are the
principal recycler of dead animals of a similar size.
MORE ABOUT LEAFCUTTER ANTS
This family of ants, known locally as bachacs, is one of the most
recognizable animals in the rainforest. Generally viewed as pests
(especially in agriculture) they are in fact one of the principal agents in
recycling nutrients in the forest. Leafcutters have been practicing
agriculture for millions of years and live almost entirely on a fungus
they produce from fresh leaves. The waste from this process is
incredibly nutritious and is quickly absorbed by plants and trees. In
fact the nutrients would probably go back to the very plants that
provided the fresh leaves in the first place.
On The Trail of Leafcutter Ants
Threats To Rainforests
Despite a widespread knowledge of the importance of rainforests they are
still under severe threat. Huge areas are being lost due to deforestation
and their integrity is being compromised by over hunting. In addition the
silent threat of climate change could well be their ultimate downfall.
The principal causes of deforestation are:
Conversion of forests to agriculture accounts for over 60% of
deforestation. Vast areas are cut, burnt and used for crops or livestock.
Rainforest soils have been shown to be invariably poor for this type of
practice. Often it is poor farmers of these regions that are forced to farm
these areas. Within a few years the fertility is gone and the farmers have
little choice but to clear new areas, only to repeat the cycle.
Again vast areas are destroyed by the effects of logging. This has been
particularly severe in South East Asia where only a small percentage of
the original forest remains. Logging not only often precedes conversion
to agriculture; it also opens up areas to be farmed because of the roads
built to transport the timber.
Deforestation is also being carried out for house building, new roads,
mining and oil exploitation. Huge areas are also flooded through the
construction of dams.
Bulldozers are used to help clear
forests. They compact the soil,
reducing the ability of the forest
to regenerate even further.
Photo: H. Singh
Deforestation and Quarrying currently occurring in Tobago
Hunting for wildmeat has occurred in rainforests for as long as people
have lived there. It is still a vital source of protein to many people in
Amazonia and Central Africa. Population sizes in rainforests have
generally been small enough for this to have little impact on the ecology
of the forest. However, problems arise when hunting extends to
providing for a wider appetite, either in cities or in other countries. This
over exploitation of animals can have a subtle but important effect ,
particularly to the biodiversity. Remember everything is linked- if you
lose one species you might loose others dependent on it. The forest
could still be standing but the variety of life would be diminished.
Hunting for the pet trade, furs and traditional medicines also play a part
in species depletion.
Why animals are hunted
• Caiman- Skins meat, oil
• Snakes- Skins
• Primates-Medical science
• Birds- Plumes, pets
• Deer- Skins, meat
Hunting in Tobago’s Rainforest
Tobago’s rainforest is well protected for its trees but all is not well for
its larger animals. People have hunted here since they first stepped
ashore many thousands of years ago. But over the last four centuries
Tobago’s larger animals, or ‘game’, have been decimated.
Why has this happened? It is the age-old thinking of “limitless
supply” people still believe they can hunt indefinitely without
repercussions. Wrong! At the current rate the animals will join the
others (shown on page 32) that have already disappeared. Although
there is a hunting season this is largely ignored and rarely enforced.
A moratorium on hunting in the reserve needs to be imposed so a
proper scientific survey can be done. From this, new stricter laws can
be implemented while giving the animals a chance to recover. Ideally
hunting should be illegal in the reserve. This will then provide a
supply of animals to the forest outside this area where hunting can be
The silent threat of climate change could hold the ultimate fate for the
rainforest. The loss of forest cover will radically alter the surrounding
climate by reducing rainfall and changing the albedo effect. Add to this
the enormous amounts of carbon dioxide released through the burning of
the forest and you have a recipe for disaster. However, as there are so
many factors involved scientists are not certain what the eventual
outcome will be. For example, is there a point in time where there is not
enough forest to produce the rain it needs to sustain itself?
Climate Change and Our Rainforests
The Greenhouse Effect
Solar radiation enters the earth’s atmosphere. Some of this radiation is
absorbed by the ocean and other living things. About one third of the
solar radiation is reflected back into outer space. However, gases such
as carbon dioxide, methane and water vapour trap radiation and warms
the earth. This heating of the earth or the greenhouse effect is a natural
phenomenon and makes life possible. By warming the earth to just the
right temperature living things are able to flourish.
Studies have shown that over the years, the average global temperature
has risen and that this is as a result of increasing levels of carbon
dioxide released into the atmosphere. This increased global temperature
or heating up of the earth is known as Global Warming.
This heating up of the earth causes changes in global weather patterns.
Known climate can therefore become unpredictable and result in the
Weather– related deaths Erosion of beaches
Increased Infectious diseases Loss of habitat and species
Increased Respiratory illnesses Forest composition
Lower crop yields Geographic range of forests
Changes in water supply and Forest health ad productivity
Climate change is one of the biggest challenges facing our world
today. Between 20 to 25% of carbon dioxide emissions come from
deforestation and land use changes. Forests play a critical role in
regulating the carbon dioxide in the atmosphere. Through the process of
photosynthesis, forests utilize large quantities of this green house gas to
make food, thereby reducing the amount in the atmosphere. By removing
forests, the gas remains in the atmosphere and further, when we burn the
trees, we release even more carbon dioxide into the environment!
It is imperative that we save what is left of our rainforests.
Here are some of things you can do:
Educate yourself & others
Reduce and Reuse paper
Reduce use of plastic and gasoline
Facts about the benefits provided by planting one tree:
Absorbs over one tonne of harmful greenhouse gases over its lifetime
Produces enough oxygen for 4 people every day (Tree Canada
Provides the equivalent cooling effect of ten room-size air conditioners
operating 20 hours a day (US Department of Agriculture)
Provides an estimated US $273 (about TT$1638) of environmental
benefits in every year of its life (American Forests)
Rainforests are awe inspiring places. Full of beauty, they provide the
earth and its people with the essence of life, not just aesthetically but
practically too. But there lurks a dark cloud over their future that
possibly threatens us all.
Tobago offers a small antidote to this with its forest reserve, providing
the world with a wonderful example of what can be achieved. However,
it is a small place and most rainforests are huge in comparison- their
protection is difficult and their future looks bleak. Ultimately their fate
depends on whether their true value can be recognised, by everyone,
from the poor farmer to the people in power.
Undeniably this comes down to money and the question:
“ are rainforests worth more standing than they are cut down? ”
We hope that we have proved that they are.
Perhaps all that is needed is a change in attitude, to realise that
everything in life, like the rainforests, is connected. Plan for the long
term. Think sustainably. Everyone would benefit not just a few.
Unfortunately, changing attitudes and behaviours still remain the hardest
task of all.
Photo: B. Bhikarry
GOING, GOING……Animals that still survive in the rainforest.
GONE……. but not forgotten. Animals that have become extinct in Tobago
Red Brocket Deer
Blue & Yellow Macaw
Annual ring - The growth layer of 1 year, as viewed on the cross
section of a stem, branch, or root.
Biological control - Control of plants, diseases, and animal pests by the
use of natural enemies.
Bole - The main trunk of a tree.
Browse - Small bushes, sprouts, herbaceous plants, small trees, etc., that
wildlife feed on.
Burn, controlled - Any burning that a landowner starts intentionally to
accomplish a particular purpose, and over which he or she exercises
some surveillance or control.
Burn, prescribed - The application of fire to land under conditions of
weather, soil moisture, and time of day, that will accomplish specific
silvicultural, wildlife, grazing, or fire hazard reduction purposes.
Canopy - A collective term for the layer formed by the crowns of the
taller trees in a forest. The canopy is the highest layer of the forest--the
intertwined branches of mature trees that shade and protect lower forest
layers and provide a habitat for insects, birds and small mammals.
Crotch - The fork of a tree or branch.
Crown - The branches and foliage of a tree.
Deciduous - Term applied to trees (commonly broadleaf) that drop all
their leaves sometime during the year.
Dendrology - The identification and systematic classification of trees
Habitat -The environment in which the plant or animal lives.
Field layer - The field layer is the first layer of growth on the forest
floor--a soft carpet of mosses, ferns, wildflowers, grasses and other low
plants. It is a habitat for many insects, mammals, reptiles and
Latitude - distance north or south from the earth's equator measured
through 90 degrees
Litter layer - The litter layer is the floor of the forest, where decaying
plant matter and fungi undergo the transformation into soil. Bacteria,
insects and worms in the litter help break down the plant matter.
Old growth - A forest that has never been changed by management or
harvesting. This term is misapplied by many to describe any forest that
appears to be old. Individual trees in this type of forest are usually over
200 years old, and there are large standing and fallen dead trees
throughout the stand.
Photosynthesis-is a process that converts carbon dioxide into organic
compounds, especially sugars, using the energy from sunlight.
Riparian zone -That area adjacent to rivers and streams identified by
vegetation, wildlife, and other qualities unique to these locations.
Sapling - A young tree of small diameter
Silviculture - The art and science of producing and tending a forest; the
theory and practice of controlling forest establishment, composition,
growth, and quality of forests to achieve the objectives of management.
Snag - A standing, dead tree or a standing section of the stem of a tree
broken off at the height of 20 ft or more. If less than 20 ft, it is properly
termed a "stub.
Soil layer - The soil layer is the foundation of the forest, supporting and
providing moisture and nutrients to plant and tree roots. It consists of
decomposed plant matter and inorganic material, such as rocks, minerals
Timber - A term loosely applied to forest stands or their products; often
applied to wood in forms suitable for heavy construction (houses, ships,
Understory - The understory is made up of bushes, shrubs, woody plants
and young trees reaching up to the forest canopy; it provides a habitat for
birds and insects.
Virgin forest - A mature or over mature forest essentially uninfluenced
by human activity.
Books and Journals
1.Trinidad and Tobago report to FAO on plant genetic resources 1996.
2.Rainforest Action Network Factsheet no.10
3.Rainforest Action Network Fact sheet no.1
4. Tobago the forgotten island. The Naturalist 4,7. 1983. Dave Hardy
5.WASA and Thames Water International- Design of a Watershed Programme for Courland
6. EMA- State of the Environment Report 1996.
7.Treatment and Cures with Local Herbs – Albetina Pavy
8 A Guide to the Convention on Biological Diversity- IUCN
9.In Search of Nature – Edward Wilson
10.Native Trees of Trinidad and Tobago – Victor Quesnel & T. Fareell.
11. The Snakes of Trinidad and Tobago – Hans E Boos
12. Wild Plants of the Eastern Caribbean – Sean Carrington
13. Neotropical Rainforest Mammals – Loise H. Emmons
14. Natures Services – Gretchen C Daily
15. An Introduction to Ecology – John Cloudsley-Thompson
16. The Private Life of Plants – David Attenborough
17. Birds of Trinidad and Tobago – Richard Ffrench
18. An Introduction to Conservation Biology- RB Primark
19. Medicinal Plants of Trinidad and Tobago – Commonwealth Secretatiat
20. The Empty Forest – Kent H. Redford, Bioscience Vol. 42. 1992
• The area of a rainforest the size of a football field is being destroyed per
• The trees of a tropical rainforest are so densely packed that rain falling on
the canopy can take as long as ten minutes to reach the ground.
• Giant bamboo plants can grow up to 9 inches per day
• Some rainforest monkeys are omnivores, eating both plants and animals
• Bats are essential for the pollination of many tropical foodstuffs such as
bananas and mangoes
• I out of 4 ingredients in our medicines come from rainforest plants
• About 2000 trees per minute are cut down in rainforests!
Help Save Our Rainforests! Be a Part of the Solution!
1. The very tallest trees in a rainforest are called emergents
2. Are rainforests important to the environment?
3. The upper parts of the trees in a rainforest are called the canopy
4. Rainforests supply food, medicine, oxygen, and clean water.
5. Does it ever freeze in a tropical rainforest?
6. Rainforests get over 100 feet of rain each year.
7. The understory, the area between the leaves and the ground, is usually:
Shady and Cool OR Bright and Hhot
8. Are tropical rainforests always found near the equator of the Earth?
9. How many species of insects live in rainforests?
Millions OR hundreds
10. Do the largest animals live on the forest floor?
Tropical Rainforest Strata: Label Me!
Read the definitions, then label the strata (layers) of the tropical
rainforest diagram below.
canopy - the upper parts of most of the trees (about 65 to 130 feet or 20
to 40 m tall). This leafy environment is full of life: insects, arachnids,
many birds, some mammals, etc.
emergents - the tops of the tallest trees, which are much higher than the
average trees (the canopy).
forest floor - the ground - it is teeming with animal life, especially
insects and arachnids, plus large animals (like anacondas and jaguars).
understory - a dark, cool environment that is under the leaves but over
the ground. Most of the understory of a rainforest has so little light that
plant growth is limited. There are short, leafy, mostly non-flowering
shrubs, small trees, ferns, and vines (lianas) that have adapted to filtered
light and poor soil.
The Blue Morpho Butterfly (Morpho menelaus) is an iridescent blue butterfly that
lives in rainforests of South and Central America, including Brazil, Costa Rica,
and Venezuela and Tobago.
Anatomy: The Blue Morpho Butterfly is a species of neotropical butterfly that has
brilliant blue wings (the females are are not as brilliantly colored as the males and
have a brown edge with white spots surrounding the iridescent blue area). The
undersides (visible when the butterfly is resting) are brown with bronze-colored
eyespots. The Blue Morpho has a wingspan of about 6 inches (15 cm). Adults
drink the juices of rotting fruit using their straw-like proboscis.
The caterpillar of the Blue Morpho is red-brown with bright patches of lime-green
on the back, and it eats the plant Erythroxylum pilchrum nocturnally (at night).
Unscramble the words below
Answers: Hunting, Deciduous, Endangered, Extinct, Drought
Colour the Beautiful Orchid Below
Feel Free to Use Your Imagination!
Popular around the globe for their beauty and variety, orchids are the largest family of plants in the
entire world. There are 25,000-30,000 different species of orchid, at least 10,000 of which can be
found in the tropics. Orchid species can differ greatly from one another, with extreme variations in
size, weight and color.