The galapagos islands map of the galapagos islands
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MangrovesMangroves are a variety of salt-tolerant trees and shrubs that thrive in shallow and muddy salt or brackish waters. They can easily be identified by their root system which have been specially adapted to their conditions by extending above the water. Vertical branches, pheumatophores, act as aerating organs filtering the salt out and allowing the leaves to receive fresh water. Mangroves are thought to have originated in the Far East but have been spread by ocean currents, to tropical regions around the world. Mangroves live within specific zones within their ecosystem. Depending on the species they occur along the shoreline, in sheltered bays, and some grow in inland estuaries. Mangroves also vary in height depending on the species and environment. The Galapagos is home to 4 types of Mangroves: Black MangroveThe Black Mangrove (Avicennia germinans) has the most salt tolerant leaves of all the mangroves which are equipped with special salt-extracting glands. Trees grow to 65 ft (20 m) in height; the long spreading branches are covered by a dark brown bark. Leaves grow in pairs and are leathery in texture with a narrow oval shape. The leaf surface is dark green and the underside is pale and often coated with salt. The trees' yellow flowers which grow in clusters, develope into a green lima bean shaped fruit. Black mangroves have a carpet of short aerial roots or pneumatophores surrounding the base of the tree. Red MangroveThe Red Mangrove (Rhizophora mangle) is the most common of the Galapagos mangroves. They are named for their reddish wood. This species is used around the world as a source of charcoal and tannins for leather working. Trees grow to 72 ft (22 m) in height but may also be seen as small bushes. The thick leathery leaves grow in pairs with a dark green upper surface and pale yellow leaf below. Red mangroves have yellow flowers that grow in groups of 2 or 3. Red mangroves can be found growing near the low tide zone as well as at higher elevations mixed with other mangrove species. Button Mangrove or Buttonwood Button Mangrove or Buttonwood (Conocarpus erecta) is not a true mangrove and is usually found in the higher mangrove elevations. They have dark gray bark and leaves which are either oval, leathery and smooth green or sharply pointed with salt glands at the base. Their “buttons” have green flowers that mature into a round purple fruit. White MangroveWhite Mangrove (Laguncularia racemosa) grows into a shrub with aerial roots close to the water. They thrive in areas with infrequent tidal flooding. Leaves are smooth, oblong and light green in color with notched tips. The Importance of Mangroves to the EcosystemMangroves are a unique part of the coastal ecosystem. Their fallen leaves and branches provide nutrients that support a variety of sea life and the shallow waters of mangrove swamps provide a nursery for young fish, crabs, shrimps, mollusks and rays. Mangroves provide nesting sites for hundreds of bird species including the Galapagos Mangrove Finch, Medium Ground Finch, Dark-Billed Cocos, Herons, Yellow Warblers, Mockingbirds and Small Ground Finch. Mangroves help protect the coastline from erosion, storm damage and wave action. They prevent shoreline erosion by acting as a buffer, catching the soils and other materials that run off the land and stabilizing the soils and nutrients lost from erosion. Threats to the MangrovesResistant by nature, mangroves have withstood natural disasters for millions of years but now this valuable ecosystem is among the most threatened habitats in the world. Mangroves have been cut and used as building materials and in the leather tanning industry. In recent years the rapidly growing shrimp industry has clear-cut large areas of mangroves to provide a cheap source of land and water for artificial shrimp ponds. Globally 50% of the mangrove forests have been destroyed due to clear cutting for shrimp farms. The northwest region of Ecuador alone has lost nearly 90% of its mangroves. Protecting Mangrove ForestsProtecting the mangrove forests requires educating consumers in wealthy nations that import luxury shrimp products. Reducing the demand for pond-raised shrimp reduces the pressure on mangroves. Stricter government laws and enforcement in protecting mangroves is also an important factor. Education at the local level regarding the importance of preserving these swamps in order to maintain the coastal environment is essential. Animals The Galapagos Islands are home to a large number of endemic fauna including invertebrates, birds, reptiles and a few mammals. Of these perhaps the Galapagos Tortoise is the best known .These giant tortoises, all of which are endangered due to hunting and introduced species, include 11 subspecies that have specific adaptations for the environment of their island homes. With a lack of predatory mammals, life on the islands is dominated by reptiles including the famous Galapagos Tortoise, land and marine iguanas, snakes, lava lizards and sea turtles. There are 27 species of reptiles in the Galapagos of which 17 are endemic (species found only in the Galapagos). The Galapagos is home to terrestrial iguanas (land iguanas), marine iguanas and a hybrid of the two. Life in the ocean is as varied and unique as it is on land. The Galapagos Marine Reserve is home to 7 species of whales and 3 types of dolphin, 18 species of morays, 5 species of rays, 12 species of sharks as well as various other underwater creatures including star fish sea cucumbers Green and Hawkbill Turtles and more than 300 species of fish.
The twenty-two species of Galapagos reptiles belong to five families: tortoises, marine turtles, lizards/iguanas, geckos and snakes. Twenty are endemic to the archipelago and many are endemic to individual islands. The Islands are well-known for their giant tortoises ever since their discovery and they played an important role in the development of Charles Darwin's theory of evolution. The name "Galapagos" originates from the Spanish word “galapago” meaning “saddle.” Giant tortoise (11 subspecies) Pacific Green Sea Turtle Marine Iguanas (7 subspecies) Galapagos land Iguana Santa Fe Land Iguana Lava lizard (7 species) Gecko (5 species) Galapagos snake (3 species) Mammals Oceanic Islands are typically lacking in mammals and the Galapagos are no exception. Only six species of mammals are native to the Islands. The absence of large predators probably accounts for the fearlessness of the other native species towards humans. Most mammals are thought to have arrived on either rafts of floating vegetation or by swimming. Sea Lions Galapagos Fur Seal Whales (7 species) Dolphins (3 species) Galapagos Bat Santa Fe Rice Rat Fernandina Rice Rat |