Natural History of Tobago
by David Rooks
About 106 million years ago in what is today the Eastern Pacific, just north of Columbia, there was a chain of volcanic islands.
The super continent of Pangea was breaking up, the Pacific plate was moving eastwards. This plate crashed into those islands and crushed them. Most were forced back towards the core of the earth to be recycled, but a few were pushed along under water ahead of the plate for many millions of years.
Within recent geological time a tiny surviving piece of that collision was pushed back to the surface and an island was born - the island we call Tobago. So Tobago is a migrant having come all the way from the Pacific to the Atlantic.
Tobago now was an island very close to the coast of South America. The last great ice age came. The ice trapped an enormous amount of the planetīs water, sea level fell as much as 100 metres.
The sea between this island and the continent dried up and Tobago became an integral part of South America. The same thing happened to Trinidad but there was a gap of water between the two islands, they were never joined.
The plants and animals of South America now migrated upwards and occupied this land.
About 10,000 years ago the ice age ended, the ice melted, the sea level rose to where we know it, but Tobago retained the flora and fauna of the continent. This left us with a diversity of life far greater than we would otherwise have had. We became a tiny oceanic island with the plants and animals of a continent.
At this point Tobago had four distinct types of forest - Mangrove Forests in our wetlands, Littoral Woodlands on the coastal edge and surrounding beaches, Seasonal Deciduous Forest from the inner edge of this to the lower level of the mountain range and Evergreen Rain Forest covering the top of the range.
When the first Europeans arrived in the early part of the 17th century, they found the land which was occupied by Littoral Woodlands and Deciduous Forest most suitable for farming. They cut them down and replaced them with their farms, mostly sugar. By the middle of the 18th century there was little left untouched of those forests except for a tiny remnant of the Deciduous surviving on Little Tobago which proved too dry for farming.
After many years of continuous conflict, with Tobago changing hands umpteen times, at the Peace of Paris in 1763 the island was ceded to Britain. This event coincided with the height of the sugar trade in Europe.
British settlers flocked to Tobago and cut down more forest, replacing it with sugar. Realising that if they continued to do so they would destroy their source of water, they declared the untouched rain forest Crown Reserve in 1764 and on the 13th of April, the Governor, Sir William Young, signed the proposed law.
This is now the oldest legally protected forest on the planet (for the purpose of conservation). Living in forests of Tobago there are 210 species of birds, many amongst the world's most beautiful, including the exquisite Red-billed Tropic Bird,
now a star in two major nature films.
Twelve species of mammals survive. The early settlers exterminated the monkey, fox, muskrat, manatee, ocelot, sloth and river otter, while we, of this generation are trying our best to exterminate the survivors. We appear to have succeeded with the red brocket deer. Some of the others that still survive are the peccary (quenk, wild hog), agouti, opossum (manicou), crab-eating raccoon, armadillo (tattoo) and red squirrel.
Tobagonians share this island with:
- 23 species of butterfly, including the Blue Emperor.
- 5 species of marine turtle, including a few precariously surviving giant Leatherback turtle.
- 24 species of snake, none of which are poisonous. Our snakes are beneficial to the environment - they are the main controllers of vermin such as rats.
- 16 species of lizard. Two of these are quite large - the Sally Painter (Tupinambis nigropunctatus) and the Green Iguana
- 14 species of frog, the most common being the brown crapaud (Bufo marinus)
- 17 species of bat, including one, the fish eating bat, that catches fish on the sea at night.
Our streams also have a wide variety of life. There are several species of fish, including the world famous Guppy. It was named after a founding member of the Trinidad and Tobago Field Naturalist Club, Lechmore Guppy, who described it for science.
And crabs, one of which carries its young in a belly pouch like a marsupial so it is called locally the manicou crab. The manicou (opossum) is the western hemisphere's only marsupial.
And crayfish, the largest is the macrobracium.
The natural predator of all these fresh water animals is the Spectacled Caiman, a small member of the crocodile family.