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Colonization, Destruction, and Preservation



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Colonization, Destruction, and Preservation


The first "permanent" human inhabitant of the Galapagos was an Irishman by the name of Patrick Watkins, who was marooned on Floreana in 1807. He spent 8 years there, raising vegetables and selling them to visiting whaling ships before stealing a boat and sailing to the mainland. A few years later the government of Ecuador established a prison colony here and they continued to maintain prison colonies in the Galapagos until the middle of the twentieth century. Various schemes for establishing coal mines on Santiago and for mining guano were suggested, but nothing became of them for the simple reason that there is no coal and far too little guano to mine. One resource that was exploited on Santiago was the mining of salt from the salt lake near James Bay. This was to salt fish and tortoise meat.

In 1869, a colony named Progesso, was established on San Cristobal under the leadership of Manuel Cobos. However, despite the name of the colony Cobos was hardly a progressive leader and his tyranny led to his murder several years later. The colony, however, survived and San Cristobal remains the seat of government in the Galapagos today. In 1893 Don Antonio Gil established a colony on the southeast coast of Isabela, which he called Villamil, and another, Santo Tomas, 20 km inland, high on the slopes of Sierra Negra. The latter was established to mine sulfur from the fumaroles in the area. Around Villamil, coral was mined and burned to produce lime. This was supplemented by fishing and cattle ranching on the moist windward slopes of Sierra Negra. These towns remain today.

European and American interest in the Galapagos was stimulated by the1924 publication of William Beebe's book Galapagos: World's End. This book marks the beginnings of the eco-tourism industry that today dominates the Galapagos economy. One of those early tourists was U.S. President Franklin D. Roosevelt, who visited the islands in 1938. There was also a trickle of Europeans immigration to the Galapagos around this time. The largest group was of 60 Norwegians who were persuaded to settle on Floreana by some young journalists and a whaler who had written about the Galapagos. Floreana turned out to be anything but the paradise the promoters had promised and although most managed to survive for a difficult year or two there some of the survivors eventually returned to Norway while others moved to the settlements on San Cristobal and Academy Bay on Santa Cruz. A few years later other Norwegians came to Santa Cruz along with a sprinkling of others from Europe, America, and Ecuador, all seeking a simpler life. Among them were the four Angermeyer brothers from Germany, who settled on Santa Cruz in 1935. Their descendents still live here, operating touring yachts and a hotel in Puerto Ayora. One of their daughters, Johanna Angermeyer, wrote an excellent book, My Father's Island, about their life here

In the early 1930's, several groups of Europeans settled on Floreana. Amoung them was Dr. Friedrich Ritter and his mistress Dore Strauch from Germany, followed by the Wittmer family, also from Germany and finally the Austrian "Baroness" Wagner de Bosquet and her entourage of 3 men, Robert Philippson, Rudolf Lorenz, and Felipe Valdiviseo. Dr. Ritter and the Baroness appear to have been curious characters. After the Baroness's arrival disputes broke out among the various groups, particularly between the Baroness and just about everyone else and, in 1934, a series of bizarre deaths occurred that have been the subject of much speculation ever since. The Baroness and Philippson disappeared without a trace and Lorenz was found dead on Marchena (one of the northern islands). Later in the same year, Ritter, a vegetarian died of food poisoning as a result of eating chicken. Dore Strauch returned to Germany shortly thereafter. Other somewhat mysterious deaths occurred in the decades that followed. The details of the "Floreana Mystery" may be found in any of several books written about it. Frau Wittmer's excellent book, Floreana, provides a first hand account of these events as well as a fascinating account her 65 years on Floreana.

In World War II, the U.S. Navy obtained permission from the Ecuadorian government to establish bases in the Galapagos to guard the approaches to the Panama Canal. An airbase was established on Baltra and a radar station on the north end of Isabela. Following the war the airbase was given to the Ecuadorian government, and eventually transformed into the present commercial airport.

The year 1935, the one hundredth anniversary of Darwin's visit, was something of a turning point in Galapagos history, as the Ecuadorian government designated several areas of the islands as wildlife preserves. Four centuries of human presence had had an adverse effect on its unique fauna. Three of the 14 races of tortoises were gone forever and populations of others were vastly reduced. The native rice rat, one of the few indigenous Galapagos mammals, two other native rat species and one bat species, were already extinct on many islands. Plants introduced on the settled islands were replacing the unique native species. Feral goats, like those released by Captain Porter, along with pigs, burros, and cattle, were defoliating some islands. Introduced rats, cats, dogs, and pigs ate the eggs and young of the native birds and reptiles. While nothing was done to provide protection for the wildlife preserves much less to reverse the damage they had already suffered, the designation represented an official recognition that there was something worth preserving in the Galapagos.

In 1959, on the one hundredth anniversary of publication of The Origin of Species, the Charles Darwin Foundation for the Galapagos Islands was incorporated in Belgium. This institution inaugurated the Charles Darwin Research Station in 1964 and initiated a program of collecting tortoise eggs and bringing them to the research station where they would be hatched and raised to an age where they had a reasonable chance of survival. They were then returned to their native islands. This occurred just in time to save the Espanola race of tortoises from extinction (only 11 females and 2 males remained of the Espanola race) and the decline in the populations of other races was reversed. A similar program was initiated for land iguanas. In 1959 the Galapagos were declared a National Park by the government of Ecuador and in 1968 the boundaries of the park, which includes 95% of the land area of the islands, and a park service were established. A few years later the ocean surrounding the islands was declared a Marine Reserve and placed under the park's jurisdiction. Organized tourism began in 1970, when 1000 tourists visited the islands. Since then the tourism industry has grown to and today more than 60,0000 people visit the Galapagos each year. The impact of this visitation to the islands has been kept to a minimum by the implementation of the tight control and regulation of tour operators. Tourists eat and sleep on their boats, are allowed to come ashore only in designated areas, and then only under the supervision of licensed guides.

Many problems remain in the Galapagos, however. The number of Ecuadorians living in the islands is increasing dramatically and straining scare resources. Many of these new "Galapagueños" fail to appreciate the delicate and unique nature of the Galapagos ecology and are demanding, sometimes violently, the right to exploit it. Fishing activities, particularly for sea cucumbers, around Fernandina threaten marine biota directly and the terrestrial biota indirectly through the introduction of foreign species to this largely pristine island. The Ecuadorian government lacks the resources, and often the political will, necessary to protect the islands from harmful activities. The worst problem, however, remains that of feral animals. Dogs, cats, and rats threaten the survival of marine iguanas and seabirds on many islands. Though their numbers have been reduced, tens of thousands of goats remain on Santiago. Goats on Pinta, once thought to have been eliminated, are once again ravaging that island. But the most discouraging situation is that of goats on Isabela. Goats had long been present on Isabela, but had been restricted to the southern part of the island. Sometime in the mid-1980's a few goats crossed the barren of desolate lava flows on the Perry Isthmus and reached Volcan Alcedo. Alcedo is home to the largest population of tortoises that, up until this time, had been little affected by humans or feral animals. In the last 10 years the number of goats on Alcedo has increased explosively and there are now between 50,000 and 100,000 goats here. The once pristine caldera has been largely defoliated. Goats have also reached Volcan Darwin and perhaps number in the thousands there. Although the battle for the Galapagos has been joined it remains to be seen whether the unique fauna and flora of the Galapagos can be preserved for future generations of tourists to enjoy and future generations of scientists to study.


Climate

One of the most fascinating aspects of the Galapagos is their climate. However, if you were expecting the swaying palms and lush vegetation of other tropical isles, you're in for a surprise. Darwin opens his chapter on the Galapagos in The Vogage of the Beagle with the following remark: "Considering that these islands are placed directly under the equator, the climate is far from being excessively hot." He also notes that "Excepting during one short season, very little rain falls, and even then it is irregular; but the clouds generally hang low." While it is true that the Galapagos are generally not "excessively hot", particularly for the tropics, they are not cool either, as daytime temperatures in the lowlands typically reach 30° C (85° F) or higher. In the same paragraph, Darwin identifies the principal reason for the Galapagos' dry and moderate climate: "this seems chiefly caused by the singularly low temperature of the surrounding water, brought here by the great southern Polar current." Today, the "the great southern Polar current" is known as the Peru, or Humbolt, Current. Carrying an enormous volume of cold water northward from the Antarctic region, it keeps the western coast of South America temperate and dry and as it passes northern Peru, the Humbolt current bends to join the Equatorial Current flowing westward across the Pacific, bathing the Galapagos in cool water.

There is another reason for the peculiar climate of the Galapagos, of which Darwin was unaware, and that is ocean upwelling. Upwelling refers to the rise of deep water to the surface which can occur as a result of both current patterns and wind action. Though the actual cause is complex, a simple explanation goes as follows: as the water of the Humbolt Current turns westward, it spreads out, or diverges. Since the water is spread out over a greater area, extra water must come from below, or upwell, to make up the difference. A more important reason for upwelling, however, has to do with winds and a phenomenon known as Ekman Transport. The trade winds blow from southeast to northwest in the southern hemisphere and from northeast to southwest in the northern hemisphere and although both the northern and southern trades blow towards the equator, these winds push water not straight ahead, but at a 45° angle to the wind direction (45° to the left in the southern hemisphere and 45° to the right in the northern hemisphere). This phenomenon is known as Ekman Transport which, like the Coriolis force, is a result of the Earth's rotation. The result is thatalthough the trade winds blow toward the equator, they push water away from it! Once again, the divergence in surface water allows deep water to rise to the surface. The oceans are thermally stratified, so that the water rising from depth is colder than the surface water. In some areas, particularly west of Isabela, the water temperature can fall below 20° C (68° F), and for most people, this is too cold for comfortable swimming!

Another interesting and important aspect of deep ocean water is that it is rich in nutrients. Most marine organisms live near the surface but when they die their bodies sink and are slowly decomposed by bacteria, releasing nutrients back into deep water. Accordingly deep water in the ocean is often rich in nutrients but because of low temperatures and the lack of light almost nothing can utilize them. When upwelling occurs, these nutrients are carried to the warm, sunlit surface where they stimulate a growth of algae, or phytoplankton. Phytoplankton form the base of the food chain in the ocean so when they flourish, everything else does too. Because of upwelling, the waters around the Galapagos are remarkably productive and rich in marine life. Areas of high productivity occur along the South American coast, as the Humbolt current joints the Equatorial Current, and on the western sides of the larger Galapagos Islands.

The windward (southeast) sides of the islands receive more moisture than the leeward sides and like elsewhere in the world, as elevation increases, the climate changes. This is particularly true on the windward sides of the islands. Accompanying this climatic change is a progressive variation of the dominant vegetation which can be distinguished as climate zones that are, perhaps, most evident on Santa Cruz. The increase in precipitation that creates these zones occurs as moist ocean air is forced up over the islands. As it rises, it cools and water vapor condenses as fog, mist, or rain. During much of the year, the ocean cools the lower part of atmosphere, creating a temperature inversion at around 300 to 700 meters (1000 to 2000 feet) elevation. The inversion inhibits the rise of moist air over the islands and the highest elevations are often above the clouds.

There are two seasons in the Galapagos. The dry, or garua, season which runs from July to December. "Garua" refers to the fog and mist that common hangs on the higher elevations during this season. The hot or wet season lasts from January through June, with March and April generally being the wettest months. The timing of the seasonal change varies somewhat and there is often a several month transition when either type of weather can occur. These seasons are also governed by oceanographic conditions. Around December, several changes occur in the atmospheric and oceanic currents. The trade winds slacken and the Intertropical Convergence Zone, the "climatic equator" that is usually located north of the geographic equator, shifts south toward the Galapagos. The slacking trade winds cause the westward flowing current to slow. This reduces the upwelling and allows warmer water to invade the region. The air warms and the inversion layer breaks down. This allows warm air to rise to the point where rain clouds form and daily afternoon showers occur. Even in this season, however very little rain actually falls at the lower elevations, particularly those in the rain shadow of highlands. Interestingly, the highlands receive more moisture from the garua than from actual rain.

Every few years, this seasonal warming is more intense and prolonged than usual. These are oceanographic events known as El Niño which are coupled to a reversal in atmospheric circulation known as the Southern Oscillation. Together they are sometimes called ENSO (for El Niño-Southern Oscillation) events. When an El Niño occurs, the entire equatorial and atmospheric circulation pattern is reversed. Currents and winds change direction and now bring warm water and air from the western Pacific to the Galapagos and coastal South America. In association with this, the normal atmospheric high pressure system in the eastern Pacific is replaced with a low pressure one and the low pressure system in the western Pacific with high pressure. Areas in northern Australia, New Guinea, and Indonesia suffer drought while heavy rains occur in the Galapagos and along the west coast of South America. In the Galapagos El Niño rains moisten even the dry lowlands, allowing vegetation to flourish. With food abundant, terrestrial animals, such as the iguanas and finches, do well. At the same time these changes inhibit the nutrient rich, cold water upwelling that normally provides an abundance of food for marine life. Sea life suffers as a result, sometimes dramatically. A particularly severe El Niño occurred in 1982-1983 and terrestrial life flourished. Galapagos finches, for example, raised several broods of young but it was a catastrophe for marine life. Sea birds of all types were unable to raise their young and there was high mortality among marine iguanas and fur seals. El Niño years establish a rhythm for Galapagos life in which the fortunes of marine and terrestrial life are exactly out of phase.

The 1997-1998 El Niño was one of the strongest climatic events of the century. Drought and wildfires plagued Indonesia and Australia while western North and South America suffered from flooding and heavy snow falls. It had the expected effect on the Galapagos: heavy rain fell between March and June of 1997, and again in the wet season of 1998; sea and air temperatures were typically 4 to 5° C above normal. This has an adverse impact on marine life, since upwelling, and hence ocean nutrient levels were reduced. Although this El Niño seems not to have devastated marine life quite as badly as did the 1982-83 event, in June of 1998, one could see sea lion carcasses and bones littering Galapagos beaches. There was also high mortality among marine iguanas and the survivors looked emaciated. Many sea birds failed to rear young. On the other hand, the abundant rainfall made the normally arid and brown lowlands verdant and terrestrial animals and birds flourished.

A La Niña event, in which the air and water temperatures are cooler than normal may be beneficial to marine life, but take a toll on land-dwellers. The El Niño-La Niña cycle is part of the rhythm of life in the Galapagos and the fauna and flora here have adapted to it. Though the weak succumb, the strong survive to pass on their genes to a new generation and life goes on.
Galapagos Island Geology

The Galapagos are a group of volcanic islands located on the equator roughly 1000 km (600 miles) west of the South American coast. Like many oceanic islands, including Hawaii, the Azores, and Reunion, the Galapagos are thought to be the product of a mantle plume. Mantle plumes are columns of hot rock, roughly 100 km in diameter that rise from deep within the Earth. These plumes rise because they are hotter (by perhaps as much as 200 degrees centigrade) and therefore less dense, than the surrounding rock. The rate of ascent is thought to be about 10 cm/year or so. The depth from which mantle plumes rise is, however, still a matter of scientific debate; some believe that plumes originate at a shallower depth, such as the boundary between the upper and lower mantle at 670 km, others believe they come from deep with in the earth’s core. One idea is that mantle plumes form at the base of the Earth's mantle, at a depth of 2900 km, where a layer of rock called D'' (D-double prime) is heated by the Earth's liquid iron core beneath it. One reason scientists believe that mantle plumes come from great depth is that they remain fixed relative to one anther over many tens of millions of years, even though the lithospheric plates above them may move thousands of kilometers. Thus the distance between the active Galapagos and Hawaiian volcanoes has remained fixed, even though the volcanos themselves are carried off in opposite directions by lithospheric motion.



Magma Generation and Volcanism

As mantle plumes near the surface they begin to melt. The melting occurs as a result of decompression (the decrease in pressure experienced by the plume as it rises) rather than any additional heating. Melting probably begins at a depth of 150 km or so and continues until the plume is prevented from further rise by the overlying lithosphere. Lithosphere is the relatively cool and rigid outer layer of the Earth that extends to depths as great as 100 km beneath oceans and 200 km beneath continents. Lithosphere forms as the underlying asthenosphere, which, though solid, is hot enough to flow, cools. The lithosphere beneath the Galapagos is relatively young, and therefore thin, perhaps no more than 15 km or so thick. Thus the region of melting beneath the Galapagos probably extends from depths of 100 or 150 km to 15 km. The temperature at these depths is 1400° C and more but by the time the melts reach the surface they have cooled to 1100-1200° C.

Mantle plumes do not melt completely. At a maximum, only about 20 percent of so of it melts. The melt, or magma, is initially present as microscopic channels wetting the surface between mineral grains but because it is less dense than the surrounding rock it quickly aggregates and begins to rise to the surface. Rising into the lithosphere, it eventually becomes trapped in large pools, called magma chambers at depths between a few kilometers and ten kilometers beneath the surface. Occasionally the magma in a chamber is able to force its way to the surface producing a volcanic eruption. Successive eruptions over hundreds or thousands of years produce a volcano and some of the magma crystallizes within the magma chamber, thickening the crust beneath the volcano.

The upward motion of a mantle plumes pushes the overlying lithosphere upward. This, together with the magmatic thickening of the crust, is responsible for the Galapagos Platform, an anomalously shallow region of the ocean upon which the Galapagos Islands sit.



The Plate Tectonic Setting of the Galapagos

The earth’s lithosphere is broken up into about 2 dozen plates which move with respect to one another. This plate motion, together with the flow of the underlying asthenosphere, is part of a system of convection that is the principal way in which the Earth looses heat. (Part of this heat is produced by decay of radioactive elements within the Earth, the other part is left over from the formation of the Earth some 4.5 billion years ago.) Mid-oceans ridges are located at the edges of plates moving away from one anther. One such mid-ocean ridge, the Galapagos Spreading Center, is located just north of the Galapagos archipelago. Mid-ocean ridges are often offset by fracture zones or transform faults. A major transform fault is located just north of the Galapagos at 91° W. Subduction zones occur along the lines where the plates collide. A major subduction zone is located along the west coast of Central and South America where the Nazca and Cocos Plates are subducting beneath the South American and Caribbean plates. Subduction zones are marked by deep trenches and overlying chains of volcanoes.

As a lithospheric plate moves over a mantle plume, a chain of volcanoes is created and these volcanoes are older in the direction of plate motion. The Hawaiian mantle plume has created a chain of volcanic islands and seamounts (known as the Hawaiian-Emperor chain) thousands of kilometers long over the past 80 million years. The Hawaiian mantle plume is located beneath the Pacific plate, which is moving to the west-north-west and the oldest of the Hawaiian Islands are located in the west-northwest. Other chains on the Pacific Plate, such as the Society Islands, run parallel to the Hawaiian-Emperor chain.

The Galapagos Islands are located beneath the Nazca Plate, which is moving east-southeast but the Galapagos plume has not produced such as simple linear chain as the Hawaiian or Society Islands. Nevertheless, the islands do get older to the south-southeast (Espanola is the oldest of the Galapagos island), and it has produced a chain of seamounts known as the Carnegie Ridge. A second seamount chain, the Cocos Ridge, extends northeast from the Galapagos Spreading Center. This ridge was also produced by the Galapagos plume because up until about 5 million years ago, the Galapagos Spreading Center was located directly over the Galapagos mantle plume. Thus a chain of volcanoes has been produced on both the Cocos and Nazca plates and the Galapagos Spreading Center has since migrated to the north.

Motion of the lithosphere eventually carries a volcano away from the plume and its magma source and the volcano then becomes extinct. The volcano and the lithosphere beneath it begin to cool and as it cools it contracts. As a result of this contraction the volcano slowly sinks beneath the sea. Thus the youngest Hawaiian volcanoes are islands but the older ones are now seamounts the tops of which become progressively deeper to the northwest. Many of these seamounts, however, were once islands. Because the Carnegie and Cocos Ridges disappear into subduction zones, it is uncertain how old the Galapagos mantle plume is. A 1990 oceanographic expedition, however, did locate an 8 million year old seamount on the Carnegie Ridge that was certainly once an island. This volcano, though now 1500 m below sea level, has rounded cobbles on a flat top, which is clear evidence of wave erosion. From this we know that there have been islands in the Galapagos for at least 8 million years. The plume, however, is certainly even older and many scientists believe that the Galapagos mantle plume is responsible for the abundant volcanic rocks of Cretaceous age that occur in the Caribbean and on the northwest margin of South America. Accordingly the Galapagos mantle plume could be as old as 90 million years and there may have been islands in this location for that long. This is of great importance in understanding the origin and evolution of the unique animals that occur on the Galapagos.

Galapagos Volcanoes

Two distinct types of volcanoes occur in the Galapagos. In the west, on the islands of Isabela and Fernandina, large volcanoes with an "inverted soup-bowl" morphology and deep calderas occur. In the east, smaller shield volcanoes with gentler slopes occur. The difference between these two volcanic morphologies appears to be due to the difference in lithospheric thickness. The fracture zone at 91° W separates oceanic crust and lithosphere of distinctly different age. West of the fracture zone at 91°W, the lithosphere is older and thicker, and therefore able to support the load imposed on it by a large volcano. East of the fracture zone, the lithosphere is too young and weak to support large volcanic edifices.

The "inverted soup-bowl" morphology of the large western volcanoes is quite unusual (though not entirely unique) and its origin is not entirely certain. The Hawaiian volcanoes, which are the largest on Earth and much larger than the largest of the Galapagos volcanoes, are more similar to the shield volcanoes of the eastern Galapagos. According to one theory, this morphology results from the way in which eruptive vents are distributed on the volcanoes. Most of the vents occur either on circumferential fissures near the flat summits, or on radial fissures on the lower flanks and aprons of the volcanoes. Relatively few vents occur on the steep upper flanks. Thus the volcano grows outward at the bottom and upward at the top, resulting in this distinctive morphology. The location of vents and fissures primarily reflects the stresses within the volcano. Why stresses in Galapagos volcanoes should differ from those of other volcanoes and lead to this distribution of vents remains unclear. An alternative hypothesis for the morphology of Galapagos volcanos is that it reflects the pattern of intrusion of magma within the volcano. In essence, magma intruded into the volcano inflates the central part, pushing the summit region upward and steepening the slopes on the upper flanks.

Another unusual characteristic of the western Galapagos volcanoes is the large size of their calderas, particularly in comparison to the size of the volcano. The presence of a caldera is responsible for the volcano's flat top; this flat top is well illustrated by Alcedo. Calderas form as a result of collapse of an underlying magma chamber. Magma within a magma chamber contributes to the support of the overlying edifice; when magma is withdrawn, the surrounding rock may not be able to bear the load and collapse results. Almost certainly, none of the calderas formed in a single event; instead they are the result of numerous episodes of collapse, as is evidenced by the uneven floors of some and benches and the walls of others. A partial collapse of the caldera on Fernandina occurred in 1968, when the northern part of the caldera floor dropped 200 meters. Collapse occurred several weeks after a brief eruption. It was observed from a distance, scientists arrived shortly after the event and this is one of the best documented examples of a caldera collapse. Once formed, caldera may broaden as parts of caldera wall collapse. This occurred on Fernandina in 1988. Calderas may also occasionally fill entirely with lava and then reform. Marchena, in the northeast, has a caldera that has been very nearly filled with lava. The floor of Genovesa's caldera is below sea level and broke on the south side, forming Darwin Bay.

Historic eruptions have occurred on many of the Galapagos volcanoes, including Fernandina, Volcan Wolf, Alcedo, Sierra Negra, Cerro Azul, Santiago, Pinta, Floreana, and Marchena. Eruptions in the recent geologic past (the last ten thousand years or so) have also occurred on Volcan Darwin, Volcan Ecuador, Genovesa, San Cristobal, and Santa Cruz. A number of submarine volcanoes many also have been active during this time. It is quite unusual for a mantle plume to produce so many simultaneous active volcanoes. In Hawaii, for example, only 6 volcanoes (including the seamount Loihi) have erupted at this same time and most of the activity in Hawaiian is found on just 3 volcanoes. In Reunion, only a single volcano has been active. It should be noted, however, that the magma output of Mauna Loa, the largest of the Hawaiian volcanoes, has probably exceeded the output of all the Galapagos volcanoes combined.

The islands of Espanola and Santa Fe are remnants of extinct volcanoes. In both cases only part of their original volcanic structure has been preserved and the remaining parts having been faulted away. Espanola and Santa Fe have been extinct for several million years. Pinzon and Rabida are both small extinct shield volcanoes that have not been active for about 1 million years. Though Santa Cruz and San Cristobal remain active volcanoes, parts of their edifices are much older, more than a million years in the case of Santa Cruz (including its small neighbors of Baltra, Seymour and Las Plazas) and nearly two and a half million years in the case of San Cristobal.

Santa Cruz, also called Indefatigable Island, is located in the center of the Galapagos archipelago. It also the center of human activity in the Galapagos and the National Park Headquarters, the Darwin Research Station, and the largest settlement in the Galapagos, Puerto Ayora, are all located on Academy Bay on the south side of the island. The main airport is located on Baltra, a small, low island separated from the northwest corner of Santa Cruz by the narrow Itabaca Channel. Santa Cruz is the only island with a road that crosses its interior (running from Puerto Ayora in the south to the Itabaca Channel crossing in the north) providing tourists a rare opportunity to see the interior and higher elevations of a Galapagos island. Santa Cruz is a shield volcano, slightly elongate in an east-west direction. A line of young cinder cones marks the crest of the island, running east southeast to west-northwest and reaching an elevation of 950 m at Cerro Crocker. This crest divides the dry leeward northern half of the island from the wetter, more heavily vegetated windward southern part.

Two distinct periods of volcanic activity are apparent on Santa Cruz. The earlier period produced the "Platform" lava series, which may be seen in the northeast and on the neighboring small islands of Baltra, Seymour, and Las Plazas, small islets just off the northeast coast. They are flat-lying or gently dipping lavas inter bedded with shallow marine sediments and lime stones ranging in age from about 1 million years to 2.3 million years old. Some of these have a pillow morphology, a characteristic of submarine eruption. These lavas record a period of volcanic growth, subsidence, and subsequent uplift. At least some of these lavas were erupted from vents in the northwest and the vents of others may be buried beneath the central highlands.



Climate Zones


Santa Cruz provides an excellent example of the changes in climate and vegetation that occur with increasing elevation. Directly adjacent the coast the dominant vegetation in the Littoral Zone are the mangroves, populated by plants that can survive in brackish or sea water. Cactus, such as the magnificent prickly pear, and Palo Santo trees dominate the Arid Zone which on the windward side of Santa Cruz range up to elevations of 150 meters. There is little soil development in this zone. The arid zone passes into the Transition Zone, which ranges in elevation up to 300 meters. In this zone, arid zone and scalesia zone plants mingle with extensive grasses and Bursera forests. Weathering of lavas is more rapid here and there is some soil development. Above this the Scalesia Zone is dominated by the weed-tree Scalesia. This is the zone of maximum fog and rain, and soils as deep as 1 meter are found. At 500 to 700 meters this zone merges into the Miconia Zone. A temperature inversion in the atmosphere at this elevation prevents moist air from rising higher, so the Miconia Zone receives less moisture than the Scalesia Zone below it. Trees thin and are replaced by dense growth of Miconia. The abundant pyroclastic material (i.e., volcanic ash) at this elevation is easily weathered and soil development is extensive. The Fern-Sedge Zone is found at the highest elevations and is generally above the clouds. What moisture these plants get is derived primarily from fog and the vegetation is dominated by low shrubs, ferns, tree ferns, and sedges. These elevations refer to the southern, windward side. On the lee side, the arid and transition zones extend nearly to the summit. The fauna changes with elevation as well, though some animals, such as the tortoise, may be found throughout a range of climatic zones. The brilliant Vermillion Flycatcher is found only in the higher elevations.

Santa Cruz is a good place to see many of the animals that make the Galapagos fauna so unique and interesting. Giant tortoises may be easily seen at the Darwin Research Station as well as in the highland tortoise preserve. Marine iguanas are quite common along the shore of Academy Bay, though notably less so than 20 years ago. Their cousins, the somewhat larger and lighter colored land iguanas, are particularly abundant on Las Plazas, as are sea lions. Darwin's finches are common around Academy Bay and although at first glance, they do not appear to be particularly interesting, it was his observation of the different adaptations and specializations of these 13 species of these birds, particularly beak shape, that most inspired Darwin's theory of natural selection.



San Cristobal, also known as Chatham, is the easternmost island in the Galápagos. It is the site of the only permanent stream in the archipelago and is also the place Darwin first went ashore in 1835. San Cristobal is also the site of El Progresso, the oldest surviving settlement in the Galapagos. San Cristobal Island is made up of two coalesced volcanoes. The southwestern half is a symmetric shield volcano made up of gently-dipping lavas and capped by a thick, deeply-weathered pyroclastic blanket with numerous satellite cinder cones. The southwestern shield became emergent around 2.4 million years ago and volcanic activity continued up to about 650,000 years ago. The northeastern half of the island is a more recently active volcano and the most recent flows are thought to be no more than a few centuries old.

Of interest to tourists is Kicker Rock, a spectacular rock formation off the northwest coast. Kicker Rock is a remnant of a pyroclastic, or palagonite, cone, i.e., the site of a volcanic eruption that became explosive when lava and seawater mixed. Tens of thousands of years of wind and waves have carved this once conical island into the structure we see today.



Española, also known as Hood, is one of the smaller Galapagos Islands, measuring 7 by 14 km and reaching an elevation of just over 200 m. It is the oldest of the emergent Galapagos Island, or at least it is the island on which the oldest lavas have been found. These lavas are 3.4 million years old as determined by K-Ar dating. Espanola appears to represent roughly the northern two thirds of a once larger volcano. The southern coast of the island is a vertical cliff 100 m or more high. This appears to be a fault scarp; the southern half of the volcano has faulted into the sea. Other east-west faults can also been seen. Thus Española appears to have been subjected to the same tectonic processes that have disrupted Santa Cruz and Santa Fe.

Since it is low, Espanola is particularly dry and inhospitable. Without a reliable source of fresh water, it has not been settled and has not been as threatened by introduced mammals as some other islands. This is not to say, however, that its wildlife has not had problems. By 1959, only 12 females and 2 males of the distinctive saddleback tortoises of the Española race remained. This was too few to maintain a breeding population. In the early 1960's all these animals, as well as an additional male located in a U.S. were brought to the Darwin Research Station and a captive breeding program begun. Thanks to this program, Española now has a growing population of young tortoises. Nests were observed in 1990 and hatchlings in 1991. By 1995, about 700 tortoises raised at Darwin Station had been returned to Española and the prognosis for this race is now quite good

While inhospitable to terrestrial life, Española is a haven for seabirds. It has the largest known colony of waved albatrosses, magnificent birds of enormous wing span. The high southern cliffs provide the elevation these large birds need to take off. Many other birds, such as the red-billed tropic bird, may also be seen there. The Española race of marine iguanas have a particularly striking red coloration. In the northeast of the island at a site called the blowhole, wave energy focused by cracks in the rocks produces enormous geysers of seawater to the delight of onlookers.

Floreana, also known as Charles or Santa Maria Island, is the southeastern most island in the archipelago. It is one of the smaller of the major islands, measuring approximately 12 by 15 km and rising to an elevation of 640 m (2000 feet). The oldest lavas on Floreana are 1.5 million years old, making it one of the older islands. At the other extreme, Captain Porter of the U.S.S. Essex reported witnessing an eruption in the center of this island in July, 1813. Though the products of this eruption have not been identified, there are a number of young flows and the island is covered with many young pyroclastic cones (pyroclastic cones are produced when lava it thrown into the air explosively), particularly in the highlands. All of these observations testify that Floreana remains an active volcano.

Floreana represents one extreme of the range of lava compositions encountered on the islands. Basalts here are distinctly more "alkalic" in composition, as opposed to the more "tholeiitic" compositions produced by most volcanoes. "Alkalic" magmas are often richer in water and CO2, gases that drive explosive eruptions. Thus the compositional difference probably accounts for the abundance of pyroclastic cones. Trace element abundances in these lavas indicate that Floreana magmas are produced at shallower depth in the mantle and by smaller extents of melting than in the rest of the archipelago. This may well reflect its position on the southern periphery of the archipelago, where the Galapagos Mantle Plume is cooled by contact with the surrounding mantle.

Floreana is one of the few islands with a reliable supply of fresh water and it has a long history of colonization, the first settler being an Irish seaman marooned on the island in the early nineteenth century. The long history of settlement has adversely affected the native flora and fauna. The Floreana race of giant tortoises was extinct by 1846. However, flamingos may still be seen in Flamingo Bay and sea turtles may be seen nesting on the beach near Cormorant Point.

Santa Fe, also called Barrington Island, is located in the central part of the Galapagos archipelago. It is one of the oldest of the Galapagos Islands. The composition of its lavas are similar in some respects to the Platform Series lavas of neighboring Santa Cruz. Santa Fe is also one of the few islands that is not volcanically active. Its maximum elevation is only about 200 m. There have, however, been unconfirmed reports of fumaroles on the island. The present island represents only a part of a larger volcanic edifice, the west coast is defined by a fault along which the western half of the volcano has been down-thrown. After volcanic activity ended (and probably only recently in a geologic sense), Santa Fe has been cut by a series of east-west faults that have produced a series of horst and grabens.

There is no fresh water on the island so it has been relatively undisturbed by human activity and feral animals. Among the unique species that can be seen there are the land iguana and Galapagos snake (whose bite is mildly poisonous).



Fernandina, also known as Narborough Island, consists of a single large volcano, which rises to an elevation of 4500 feet (1400 m). It is probably the youngest volcano in the archipelago and is certainly the most active, erupting every few years, most recently in 1988, 1991, and 1995 (when it produced a large lava flow from a vent on the west flank). Like the volcanoes of Isabela, it has a distinctive "inverted soup-bowl' shape with steep upper slopes and a large central caldera. Fernandina's caldera is over 1100 feet deep and at times, a small lake has formed in the north part of the caldera. The lake was last present in 1988 but disappeared after a section of the caldera wall collapsed.

Calderas form as a result of collapse following magma withdrawal from the underlying magma chamber. The calderas of the Galapagos probably form from multiple collapses. The most recent collapse (and the only historically documented collapse of a caldera in the Galapagos) on Fernandina occurred in 1968. The collapse followed a brief eruption at an elevation of about 700 m on the eastern flank on May 21. At 10 AM on June 11, an earthquake occurred and was followed by the rise of a large white cloud that was visible from Santa Cruz. At 4 PM, a dark ash cloud was spotted by a fishing boat in Urvina Bay, 35 km east of the caldera. At 5 PM a large boom was heard and this was followed by smaller explosions for the next several hours and a number of earthquakes that lasted for more than a week, the largest of which was a magnitude 5 occurring on June 15. A party from the Darwin Station reached the summit on June 19, but could see little because of the dust generated by constant avalanches. When the dust finally did clear a week later, it was apparent that the southeastern part of the caldera floor had dropped as much as 300 m, with only minor subsidence on the opposite side. A southeast section of Fernandina's caldera wall collapsed following the 1988 eruption, widening the caldera by 300 m and producing a 250 m thick pile of debris in the bottom.

Fernandina has not suffered as much from the presence of man (particularly, the animals he has left) as other islands and the indigenous wildlife is still abundant. Among the animals to be seen here are marine and land iguanas, tortoises, hawks, sea lions and a great variety of sea birds, such as the flightless cormorant.

The Cerro Azul volcano occupies the southwest corner of Isla Isabela (Albermarle Island). Although smaller than it neighbor to the west, Sierra Negra, at 1690 m (5541 feet) its summit is higher. Cerro Azul is quite active, with 9 known historic eruptions, the most recent of which began in Sept, 1998 and has continued into October. Because of its remoteness, it is likely that many eruptions over the last several hundred years have gone unnoticed. The composition of Cerro Azul's lavas is quite uniform and rather similar to that of Sierra Negra's. Both Cerro Azul and Sierra Negra have strong enrichments in incompatible elements, indications that these melts are derived primarily from the Galapagos mantle plume.



Rabida, also known as Jervis Island, is one of two small islands located to the south of Santiago. Though small, it contains a great variety of rock and lava types, including basalt, ferrobasalt, icelandite, and trachyte. The range of lava compositions is a result of fractional crystallization. As magma cools, crystals form and settle out. As a result, the composition of the magma changes, generally becoming richer in silica and poorer in magnesium. The xenoliths are fragment of magma that crystallized at depth and where broken off and carried to the surface during an eruption. It is interesting that these differentiated rocks (i.e., products of extensive fractional crystallization) are restricted to the central portion of the Galapagos archipelago, occurring on Alcedo, Pinzon, and Rabida.

Rabida is essentially a cluster of steep-sided, coalescing domes, flows, and pyroclastic cones. An irregular depression in the center may be a crater, but it has no caldera. The oldest rocks on Rabida are about 1 million years old. Some of the pyroclastic cones on the north coast are probably much younger. A salt pond formed between these cones is one of the many places where one can see flamingos in the Galapagos. These spectacular birds feed exclusively on the brine shrimp found in these saline ponds. Interestingly, their distinctive pink color comes from the pigments found in the shrimp. Young flamingos are white and only acquire the pink color after they begin to feed on the shrimp.


Galapagos Wildlife

Plant life


As else where on our planet green plants form the base of the food chain and are the basis of all life on and around the Galapagos Islands. Of the approximately 500 species of "higher" plants found on these islands today about 40% are endemic. These plants combined with the 300 species of introduced plants and 500 species of mosses, lichens and liverworts give the Galapagos its complex ecosystem.

The island's flora is found in several specific life zones and an understanding these zones helps with the identification and appreciation of the wildlife found here. From the Mangrove Swamps that cover the wet coastal zone and the Prickly Pear Cactus of the Arid Lowlands to the Scalesia Trees and Miconia of the higher Humid Zones the Galapagos hosts an interesting array of flora.



Life Zones


The climate on the islands runs a gradient from the dry low lying areas along the coast to the high moist areas near the volcano tops. In total 7 life zones have been described within the archipelago.


Various plants and animals have adapted over the years to the conditions of the islands and in some cases the specific conditions of the zone in which they are found. Many plants are restricted, in their distribution, to a specific zone, and the animals that dependent on those plants can be found there as well. Depending on the conditions, some birds and animals migrate between zones.


Coastal Zone


The lowest life zone on the island is the coastal zone and the plants that exist on the seas edge can be divided into two sub-groups, the Wet Coastal Zone or Mangrove Zone and the Dry Coastal Zone or Beaches and High Tide Areas.

Mangroves live in the Wet Coastal Zone. These salt-tolerant trees and shrubs thrive in shallow and muddy salt or brackish waters. In the Galapagos there are 4 species of Mangroves including the Black Mangrove, White Mangrove, Red Mangrove, and Button Mangrove.

The Dry Coastal Zone is made up of the dry sandy area from the sea to the high water line. This area supports low lying spreading plants which are able to retain water in their leaves and stems. One of the most conspicuous of these plants is the Sesuvian portulacastrum a herb whose stems turn a bright reddish color during the dry season.

Arid Lowlands Zone


As an island slopes from the beach to an elevation of about 197 ft (60 m) elevation an arid desert like zone occurs. This region is home to the many Cactus that live in the Galapagos including the Prickly Pear Cactus, Lava Cactus and Candelabra Cactus. The endemic lava morning glory and passionflower are vines that can also be found in the Arid Lowlands. The silvery leafed Palo Santo Tree with its collection of lichens grows near the upper portion of the Arid Lowlands Zone.

Transitional Zone


Plants characteristic of both the Arid Lowlands and the Upper Moist Zones are found in the Transition Zone. This zone is home to a variety of small trees and shrubs including the endemic Pega Pega Tree and the Guaybillo, which produces a small white flower that develops into a fruit similar to its cousin the Guava. The Galapagos Tomato, endemic to the islands is a salt resistant tomato that has been used to create a hybrid capable of growing in salty soil around the world.

Scalesia Zone


The lowest of the "humid" zones this zone is named for the daisy tree that grows at altitudes of between 970 &1970 ft (300 - 600 m) elevation. The Scalesia is one of the few trees in the Aster Family and grows to heights of 16 - 50 ft (5-15 m). Its trunk and branches are covered with moss and lichens. This area is humid and has the feel of a cloud forest.

Since humans arrived in the islands the number of Scalesia Trees has been greatly reduced. Introduced pigs and goats devour the young plants. People also introduced the Guava, a plant whose dense growth patterns steals nutrients and eventually makes it impossible for the competing native plants to survive.



Miconia Zone


Above the Scalesia Zone at 1950 - 2300 ft (600-700 m) is a humid zone named for the Miconia shrub that once dominated this region. Miconia robinsoniana grows to heights of 10-13 ft (3-4 m) and is easily identified by its yellow or reddish shaded leaf margins. Miconia are endemic to the Galapagos, but since the arrival of man it has become the most endangered plant in the islands. Introduced cattle have grazed it to dangerously low levels.

Pampa Zone


The highest vegetation zone in the Galapagos is found on those islands with elevations of more than 3000 ft (900 m). This is the Fern-Sedge or Pampa Zone. The appearance of this zone depends on the amount of moisture it receives. This region contains no true trees or shrubs but the tall Galapagos Tree Fern and several Liverworts are commonly found here.

Galapagos Cactus


Cacti are the most common plants of the dry inland portions of the Galapagos Islands. These succulents are able to store water in their stems and leaves and survive in hostile climates and during times of drought. Most cacti have spines, which have evolved from leaves. These are a fundamental part of the Cacti, important as a guard against grazing animals and providing shade to help keep the internal temperature of the plant down. Spines also channel any rainwater towards the base of the plant. The waxy coating that covers the skin of the cactus, known as the glaucus bloom, reduces evaporation by the plant by holding in moisture. Leaf like stems known as pads store and conserve moisture and work as photosynthetic organs for the cacti.

Endemic cacti in the Galapagos include the Lava Cactus, Candelabra Cactus, and the species of Opuntia (Prickly Pear) found in the Galapagos.



Prickly Pear Cactus (Opuntia Cactaceae)


Native to the tropical and subtropical regions of the United States, Baja California and the Sonora Desert region of Mexico the prickly pear has been transplanted by humans all over the world and is now thought by many botanists to be the most widely distributed plant on earth.

An endemic species of Opuntia cactus is the most common cacti on the islands. It grows like a shrub except on those islands where herbivores are a threat and here the trunks can grow up to 5 ft tall. The prickly pear cactus is the staple in the diet of land iguanas & tortoises'. The yellow flowers develop into an orange-red thorn covered fruit.



Several different varieties of prickly pear cactus have developed on in the Galapagos. These range in size and shape from the Opuntia echios variation gigantea which may grow to 40 ft. (12 m) in height to the Opuntia echios variation barringtonensis found on Santa Cruz whose trunk can measure 4 ft. (1.25 m) in diameter. These Galapagos Cacti provide habitat and a source of food source for many of the birds and animals on the islands including two species of Finch, Iguanas, Doves, Tortoises and Mockingbirds.

Lava Cactus (Brachycereus nesioticus)


Found in lava the fields, as their name suggests, these small cactus grow in clumps measuring up to 23 in (60 cm) in height. New growth on the cacti is yellow but as the cacti matures the color fades, becoming paler and eventually turns to a gray or black color with age. The creamy white flowers are visible in the early morning hours but have usually faded by 8 AM.

Candelabra Cactus (Jasminocereus thouarsii)


Named for its shape this large endemic cactus grows to heights of 23 ft (7m). Its tube shaped pads resembles the Organ Pipe Cactus of the Sonora Desert. The1 - 2 inches (2-6 cm) long green or red flowers open before dawn and develop into fruits of the same colors. The Candelabra Cactus can be seen on the cliffs outside Puerto Ayora on Santa Cruz.

Mangroves


Mangroves 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 Mangrove


The 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 Mangrove 


The 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 Mangrove 


White 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 Ecosystem


Mangroves 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 Mangroves


Resistant 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 Forests


Protecting 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.
Reptiles

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

Galapagos Marine Life


The combination of warm tropical waters and the upwelling, nutrient rich, Humboldt Current allows the Galapagos Islands to support a wide array of marine life. These waters are home to sharks, sea turtles, sea lions, and 306 species of fish, 25% of which are endemic. There are few reef building corals in these waters but numerous crevasses in the lava serve some of the same functions as a reef in other environments. Smaller fish and invertebrates make their home in the lava and larger fish live near the lava area where they feed on the smaller fish.

Viewing the Marine Life


Diving in the Galapagos has been rapidly increasing in popularity over the last few years. These trips often visit some of the remote island areas, like Darwin and Wolf, where land visits are not possible, but diving is exceptional. The highlight of these trips is viewing the Galapagos' big animals including Whale and Hammerhead Sharkes.

Natural history cruises offer snorkeling excursions in place like the Devil's Crown, a submerged volcano, which offers an experience similar to that of swimming in a tropical fish tank.



Sea Turtles


The Pacific Green Sea Turtles spend most of their lives in the ocean. Adults grow to more than 3 ft (1 m) in length with a body weight of up to 400 lbs. (180 kg). These cousins to the tortoise mate in the waters near the Galapagos and are often seen near Caleta Tortuga Negra on Santiago. Males never leave the sea, but females come ashore on beaches to nest. Green Sea Turtles are an endangered species. Turtle nests are destroyed and the eggs are eaten by humans, pigs, rats and dogs. Hawks, herons, mockingbirds, and frigatebirds prey on young hatchlings. If the young turtles make it to the sea, large fish and sharks hunt them.

Whales & Dolphins


During the19th century whale oil was an important source of lamp oil and used around the world. Whales, dolphins and porpoises all have a blubbery layer of fat around their body which allows them to stay warm in cold waters and provides them with extra energy during long migrations. It was this blubber the whalers sought and they would melt it down to produce whale oil. Due to the richness of the seas near the Galapagos Islands, whales migrate here to feed and for a time these island were the center of the whaling industry in the Pacific Ocean. The practice of whaling has nearly stopped and many of these large mammals still visit the Galapagos during their migrations. Whales, Dolphins and Porpoises make up the family of Cetaceans which can be divided into 2 groups; those with teeth and those with Baleen Plates.

Baleen Plates are large, horny triangular pieces of whalebones that grow on the upper jaws of toothless whales. Baleen whales push seawater through these plates straining out the plankton, shrimp, sardines and other small creatures on which they feed. Baleen whales are the world’s larger animals and include the Blue, Finback, Sei, Humpback, Bryde's and Minke Whales, all which can be seen in the Galapagos waters.

Toothed Cetaceans are a more diverse group and include the Sperm Whale, Orca, False Killer Whale, Short Finned Pilot Whale, and several species of Dolphins. All are frequently seen in the waters surrounding the Galapagos. Bottled Nosed and White Bellied Dolphins are common here and may often be seen riding the bow wave in front of boats. White

 

Birds


Long known as a haven for birders, the Galapagos Island's native bird life includes 57 residents almost half of which are endemic. Darwin's Finches include 13 species that have adapted to their specific island setting. Other endemics include the Lava Gull, Galapagos Penguin, Dark-Rumped Petrel, Galapagos Flightless Cormorant, Lava Heron, Galapagos Martin and Galapagos Dove.

In addition to the permanent residents more than 700,000 migratory sea birds can be seen in the islands. The Galapagos is home to almost 1/3 of the world’s Blue Footed Booby population, the highest concentration of Masked Boobies and the largest colony of Red Footed Boobies.



Darwin's Finches


The Galapagos Islands is home to 13 species of finch, belonging to 4 genera. These finches are thought to have all evolved from a single species similar to the Blue-Black Grassquit Finch Volatina jacarina commonly found along the Pacific Coast of South America. Once in the Galapagos these finches adapted, over time, to their specific habitats and the size and shape of their bills reflect their specializations. The Vegetarian and Ground Finches have crushing bills, the Tree Finch has a grasping bill and the Cactus, Warbler and Woodpecker Finches have probing bills.

All of Darwin's Finches are sparrow sized and similar in appearance with gray, brown, black or olive feathers. They have short rounded wings and a rounded tail that often appears cocked to one side. They vary in diet, some eating seeds and others insects. Ground Finches eat ticks they remove with their crushing beaks from Tortoises, Land Iguanas and Marine Iguanas and they have been known to kick eggs out onto rocks where they feed on their contents. On Isla Wolf the Sharp Beaked Ground Finch is known as the "Vampire Finch" as it has been known to jump onto the backs of Masked and Red-Footed Boobies pecking at their flesh and feeding on their blood. Woodpecker and Mangrove Finches sometime use small twigs and cactus spines as tools to probe for insect larva under bark and in dead tree branches.

Though each species of finch has adapted to a specialized feeding pattern, most are generalized eaters. These specialized adaptations are of survival importance during the dry season and in times of drought when little of their preferred food is available. It is during these stressful times that these specialized tools allow the birds to compete for limited food resources with other birds and animals.
Breeding Seasons for some Galapagos Island Nesters

Waved Albatross - April-May with some eggs in June-July



Blue-Footed Booby - January-December

Masked Booby - August-February with some eggs in March, May, and July

Red-Footed Booby - September-January, March-July

Flightless Cormorant - March-September with some eggs October-February

Magnificent Frigatebird - June-September with some eggs October-May

Great Frigatebird - January-December

Lava Gull - Some eggs February, April-May, July-August, and October-November

Swallow-Tailed Gull - January-December

Brown Noddy - November-July with a some eggs August-September

Galapagos Penguin - November-July with a some eggs August-September

Hawaiian Petrel - February-March and June-July with some eggs in August

Band-Rumped Storm Petrel - May-June and November-December with some eggs January-February, April, and July

Wedge-Rumped Storm Petrel - May-June with some eggs February-March

Red-Billed Tropicbird  (Plaza) - September-January with some eggs February, June, and August

Red-Billed Tropicbird (Tower-Daphne) - January-December

Brown Pelican - January-December

Audubon's Shearwater - January-December


Galapagos Islands Bird List

1. Galapagos Penguin Spheniscus Mendiculus___________________________________________________

2. Pied-Billed Grebe Podilymbus Podiceps _____________________________________________________

3. Waved Albatross Diomedea Irrorata ________________________________________________________

4. Black-Browed Albatross Diomedea Melanophris ______________________________________________

5. Black-Footed Albatross Diomedea Nigripes __________________________________________________

6. Southern Fulmar Fulmarius Glacialoides____________________________________________________

7. Cape Petrel Daption Capense ______________________________________________________________

8. Dark-Rumped Petrel Pterodroma Phaeopygia _________________________________________________

9. White-Winged Petrel Pterodroma Leucoptera ________________________________________________

10. Parkinson’s Black Petrel Procellaria Parkinsoni ______________________________________________

11. Wedge-Tailed Shearwater Puffinus Pacificus ___________________________________________________

12. Sooty Shearwater Puffinus Griseus ___________________________________________________________

13. Audubon’s Shearwater Puffinus lherminieri _____________________________________________________

14. Flesh-Footed Shearwater Puffinus Carneipes ____________________________________________________

15. White-Vented Storm-Petrel Oceanites Gracilis __________________________________________________

16. White-Faced Storm-Petrel Pelagodroma Marina _________________________________________________

17. White-Bellied Storm-Petrel Fregetta Grallaria __________________________________________________

18. Wedge-Rumped Storm-Petrel Oceanodroma Tethys _______________________________________________

19. Band-Rumped Storm-Petrel Oceanodroma Castro _______________________________________________

20. Leach’s Storm-Petrel Oceanodroma Leucorhoa __________________________________________________

21. Markham’s Storm-Petrel Oceanodroma Markhami _______________________________________________

22. Red-Billed Tropicbird Phaethon Aethereus _____________________________________________________

23. Brown Pelican Pelecanus Occidentalis_________________________________________________________

24. Blue-Footed Booby Sula Nebouxii _____________________________________________________________

25. Masked Booby Sula Dactylatra _______________________________________________________________

26. Red-Footed Booby Sula Sula ________________________________________________________________

27. Flightless Cormorant Nannopterum Harrissi ______________________________________________________

28. Magnificent Frigatebird Fregata Magnificens ______________________________________________________

29. Great Frigatebird Fregata Minor ________________________________________________________________

30. Great Blue Heron Ardea Herodias _______________________________________________________________

31. Great Egret Egretta Alba _______________________________________________________________________

32. Snowy Egret Egretta Thula _____________________________________________________________________

33. Lava Heron Butorides Sundevalli ________________________________________________________________

34. Cattle Egret Bubulcus Ibis_______________________________________________________________________

35. Black-Crowned Night-Heron Nycticorax Nycticorax __________________________________________________

36. Yellow-Crowned Night-Heron Nyctanassa Violacea __________________________________________________

37. American Flamingo Phoenicopterus Ruber _________________________________________________________

38. Black-Bellied Whistling-Duck Dendrocygna Autumnalis ______________________________________________

39. White-Cheeked Pintail Anas Bahamensis____________________________________________________________

40. Blue-Winged Teal Anas Discors __________________________________________________________________

41. Galapagos Hawk Buteo Galapagoensis______________________________________________________________

42. Osprey Pandion Haliaetus _______________________________________________________________________

43. Peregrine Falcon Falco Peregrinus ________________________________________________________________

44. Galapagos Rail Laterallus Spilonotus _______________________________________________________________

45. Paint-Billed Crake Neocrex Erythrops _____________________________________________________________

46. Common Moorhen Gallinula Chloropus ____________________________________________________________

47. Purple Gallinule Porphyrula Martinica _____________________________________________________________

48. American Golden-Plover Pluvialis Dominica ________________________________________________________

49. Black-Bellied Plover Squatarola Squatarola _________________________________________________________

50. Semipalmated Plover Charadrius Semipalmatus ______________________________________________________

51. Killdeer Charadrius Vociferus ____________________________________________________________________

52. Wilson’s Plover Charadrius Wilsonia ______________________________________________________________

53. Surfbird Aphriza Virgata ______________________________________________________________________

54. Ruddy Turnstone Arenaria Interpres _____________________________________________________________

55. Black Turnstone Arenaria Melanocephala _________________________________________________________

56. Solitary Sandpiper Tringa Solitaria ______________________________________________________________

57. Lesser Yellowlegs Tringa Flavipes ________________________________________________________________

58. Greater Yellowlegs Totanus Melanoleucus __________________________________________________________

59. Spotted Sandpiper Actitis Macularia________________________________________________________________

60. Wandering Tattler Heteroscelus Incanum ___________________________________________________________

61. Willet Catoptrophorus Semipalmatus ______________________________________________________________

62. Red Knot Calidris Canutus_______________________________________________________________________

63. Least Sandpiper Erolia Minutilla _________________________________________________________________

64. Baird’s Sandpiper Erolia Bairdii _________________________________________________________________

65. Pectoral Sandpiper Calidris Melanotos _____________________________________________________________

66. Semipalmated Sandpiper Ereunetes Pusillus _________________________________________________________

67. Western Sandpiper Erenetes Mauri ________________________________________________________________

68. Sanderling Crocethia Alba_______________________________________________________________________

69. Stilt Sandpiper Micropalama Himantopus __________________________________________________________

70. Whimbrel Numenius Phaeopus ___________________________________________________________________

71. Marbled Godwit Limosa Fedoa ___________________________________________________________________

72. Short-Billed Dowitcher Limnodromus Griseus _______________________________________________________

73. Black-Necked Stilt Himantopus Himantopus ________________________________________________________

74. Wilson’s Phalarope Steganopus Tricolor ___________________________________________________________

75. Red Phalarope Phalaropus Fulicarius ______________________________________________________________

76. Red-Necked Phalarope Lobipes Lobatus ____________________________________________________________

77. Great Skua Catharacta Skua _____________________________________________________________________

78. Pomarine Jaeger Stercorarius Pomarinus ___________________________________________________________

79. Laughing Gull Larus Atricilla ____________________________________________________________________

80. Franklin’s Gull Larus Pipixcan ___________________________________________________________________

81. Lava Gull Larus Fuliginosus _____________________________________________________________________

82. Swallow-Tailed Gull Creagrus Furcatus ___________________________________________________________

83. Common Tern Sterna Hirundo ___________________________________________________________________

84. Sooty Tern Sterna Fuscata ______________________________________________________________________

85. Royal Tern Sterna Maxima _____________________________________________________________________

86. Brown Noddy Anous Stolidus ____________________________________________________________________

87. White Tern Gygis Alba _________________________________________________________________________

88. Eared Dove Zenaida Auriculata __________________________________________________________________

89. Galapagos Dove Zenaida Galapagoensis ___________________________________________________________

90. Black-billed Cuckoo Coccyzus erythrophthalmus _____________________________________________________

91. Dark-billed Cuckoo Coccyzus melacoryphus_________________________________________________________

92. Groove-billed Ani Crotophaga sulcirostris __________________________________________________________

93. Barn Owl Tyto Alba ____________________________________________________________________________

94. Common Nighthawk Chordeiles Minor _____________________________________________________________

95. Belted Kingfisher Ceryle Alcyon __________________________________________________________________

96. Vermilion Flycatcher Pyrocephalus Rubinus _________________________________________________________

97. Large-billed Flycatcher Myiarchus Magnirostris _____________________________________________________

98. Purple Martin Progne Subis ______________________________________________________________________

99. Southern (Galapagos) Martin Progne Modesta _______________________________________________________

100. Sand Martin Riparia Riparia ____________________________________________________________________

101. Barn Swallow Hirundo Rustica __________________________________________________________________

102. Cliff Swallow Petrochelidon Pyrrhonota ___________________________________________________________

103. Hood Mockingbird Nesomimus Macdonaldi _______________________________________________________

104. San Cristobal Mockingbird Nesomimus Melanotis ___________________________________________________
105. Galapagos Mockingbird Nesomimus Parvulus ______________________________________________________

106. Charles Mockingbird Nesomimus Trifasciatus_______________________________________________________

107. Cedar Waxwing Bombycilla cedrorum ____________________________________________________________

108. Yellow Warbler Dendroica Petechia ______________________________________________________________

109. Summer Tanager Piranga Rubra ________________________________________________________________

110. Indigo Bunting Passerina cyanea _______________________________________________________________

111. Large Cactus-Finch Geospiza Conirostris _________________________________________________________

112. Sharp-Billed Ground Finch Geospiza Difficilis _____________________________________________________

113. Medium Ground Finch Geospiza Fortis ___________________________________________________________

114. Small Ground Finch Geospiza Fuliginosa _________________________________________________________

115. Large Ground Finch Geospiza Magnirostris ________________________________________________________

116. Cactus Finch Geospiza Scandens _________________________________________________________________

117. Woodpecker Finch Camarhynchus Pallidus ________________________________________________________

118. Small Tree Finch Camarhynchus Parvulus _________________________________________________________

119. Medium Tree Finch Camarhynchus Pauper ________________________________________________________

120. Large Tree Finch Camarhynchus Psittacula ________________________________________________________

121. Mangrove Finch Camarhynchus Heliobates ________________________________________________________

122. Warbler Finch Certhidea Olivacea _______________________________________________________________

123. Vegetarian Finch Platyspiza Crassirostris __________________________________________________________
Field Notes & Write ins: ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

RECOMMENDED READING

An excellent way to prepare for your visit to Ecuador and the Galapagos Islands is to read about them. Knowing something about the history, culture, people, food, shopping, wildlife and places of interest can make your trip more enjoyable and provide you with a much richer experience. Novels written by indigenous authors often give valuable insights into the people and their cultural and social values.

Not specific to Ecuador or the Galapagos but a really excellent book that will provide much information is "Guns, Germs and Steel" by Jared Diamond. 1999. W.W. Norton & Co. ISBN 0-393-31755-2. I rate this as one of the best background books I have ever read. The following is list of authors and titles that you may wish to consider reading in preparation for your expedition.

Beebe, William Galapagos: World's End. New York: Dover Publications, 1924. The romantic account of a scientific expedition sponsored by the New York Zoological Society.

Crow, John. The Epic of Latin America. Third Edition, 1980. A big book on a big topic, but you can pick and choose the chapters.

*Darwin, Charles The Voyage of the Beagle. London: John Murray, 1845.

Darwin, Charles The Origin of Species. London: John Murray, 1859.

Eibl-Eibesfeldt, Irenaus Galapagos: The Noah's Ark of the Pacific. New York: Doubleday, 1961.

Farb, Nathan, and Michael Jackson. Galapagos. New York: Rizzoli International Publications Inc., 1989. Maybe the best photos of the big photo books. Also, at $60, the most expensive.

Fjeldse, Jon, and Niels Krabbe. Birds of the High Andes. The Zoological Museum of the University of Copenhagen, 1990. 850 pages, for the serious birder.

Grant, Peter R. Ecology and Evolution of Darwin's Finches. Princeton University Press, 1986.

Green Clive. Birding Ecuador. Available through the American Birding Association. A guide to the top birding spots around Ecuador, including bird lists for each.

Grove, Jack Stein and Robert J. Lavenberg The Fishes of The Galapagos. Stanford University Press, 1997. An extraordinary record, twenty years in the writing; 936 pages, 521 illustrations. $125.00.

Harris, M.P. A Field Guide to the Birds of the Galapagos. London: Collins, 1974.

Hickin, N. Animal Life of the Galapagos . Quito, Ecuador: Libri Mundi, 1979.

Hilty, Steven L., and William L. Brown A Guide to the Birds of Colombia, Princeton University Press, 1986. Until there's a guide to Ecuador, this is the one to use.

Humann, Paul. Galapagos: A Terrestrial and Marine Phenomenon. Quito: Ediciones Libri Mundi, 1988.

Jackson, Michael H. Galapagos - A Natural History Guide, Calgary, Alberta: The University of Calgary Press, 1985.

Lewin, R. and S.A. Thompson Darwin's Forgotten World. London: Bison Books, 1978.

Melville, Herman. "The Encantadas, or Enchanted Isles," The Shorter Novels of Herman Melville. New York: Fawcett Publications, 1967. He found them more cursed than enchanted.

Merlin, Godfrey. Field Guide to the Fishes of Galapagos. London: Wilmot Books, 1988.

Miller, Tom. The Panama Hat Trail. New York: Vintage Books, 1986. About the only book around that gives you a glimpse of the life and times of modern Ecuador.

Nelson, Bryan. Galapagos: Islands of Birds. New York: William Morrow. All about the life and times of the sea birds of Galapagos.

Patzett, Erwin. Fauna del Ecuador. Quito: Banco Central del Ecuador, 1988. Only available in Quito, and as you may have noticed, in Spanish. But it's all there is at the moment on the animals of the area.

Perry, R. The Galapagos Islands. New York: Mead, Dodd, 1972.

Perry, R., ed. Galapagos - Key Environments. Oxford: Pergamon, 1984.

Rogers, Barbara Radcliffe. Galapagos. Mallard Press, 1990. A coffee-table photo book, with very informative text as well.

Salwen, Peter. Galapagos: The Lost Paradise. Image Bank, 1989. Coffee-table photo book.

Schofield, Eileen K. Plants of the Galapagos Islands. New York: Universe Books, 1984. A field guide to the plants.

Thorton, Ian. Darwin's Islands: A Natural History of the Galapagos. New York: The Natural History Press, 1971.

Weiner, Jonathan. The Beak of the Finch: A Story of Evolution in Our Time. New York: Knopf, 1994. Two biologists study and record evolution in action among Darwin's finches.

Wiggins, Ira L. and Duncan M. Porter. Flora of the Galapagos Islands. Stanford, Calif.: Stanford University Press, 1971.

Wittmer, Margaret. Floreana. Shropshire, England: Anthony Nelson Ltd., 1989. An account of the mysteries of Floreana, by the grand dame of Galapagos.


BEWARE OF ENDANGERED WILDLIFE PRODUCTS


GUIDELINES FOR TOURISTS, Prepared by TRAFFIC (U.S.A.)

Some attractive items offered for sale abroad are made from the hides, shells, feathers and teeth of endangered wildlife. Although some of these may legally be bought in other countries, U.S. and international laws may make it a crime to bring them back into the U.S. Before buying wildlife items, exotic pets, or plants, check to be sure that it is legal to import it into the U.S. Illegal items may be confiscated by U.S. customs or wildlife inspectors and significant fines levied.

The following information provides some guidelines with regard to illegal wildlife and wildlife products that may be for sale abroad.

Reptile Skins and Leathers

Products made from skins of crocodiles are common in European and Asian marketplaces, but most may not be imported into the United States. These include products of the black caiman, American crocodile, Orinoco crocodile from Latin America and the Caribbean, the Philippine crocodile, the Chinese alligator and the African Nile crocodile.

Products made from Latin American caimans and crocodiles are also very common in Europe, but are likely to be illegal. Caimans are protected in most of the countries in which they occur. Caiman products made from skins originating in Colombia, French Guiana, Guyana and Suriname may be legal. However, the illegal quantities of skins from this region far outweigh the legal quantities.

Most South American lizard skin products may be brought into the U.S. Exceptions are those originating in Brazil and Paraguay, which ban their export. A number of Asian countries, including India, Nepal and Pakistan, protect lizards, so products from Asian lizards, especially the popular monitors, may be illegal.

Snakeskin products made from large, boldly patterned species like boa constrictors, anacondas and pythons, as well as from smaller snakes, are popular here and abroad. In general, you may import snakeskin products. However, Latin America, Brazil, Ecuador, Mexico, Panama and Paraguay prohibit the export of snakeskin, making it illegal to import products made from skins originating in these countries. You may also encounter problems with skins from certain Asian countries, such as India, which permit only a limited trade in products finished in that country.

All sea turtle species are protected under U.S. and international law. Sea turtle shells, shell jewelry, leather, eggs, meat, and creams made with sea turtle oil cannot enter the U.S. legally.



Furs - Furs from ranched animals that may be brought into the U.S. include mink, chinchilla, nutria, ermine and some fox.

Furs of wild beaver, raccoon, opossum, fox, coyote, North American river otter, bobcat and lynx may also be imported into the U.S.

Furs from large spotted cats such as jaguar, leopard, snow leopard and tiger, and from smaller spotted cats such as ocelot, margay and tiger cat, may not be imported into the U.S. In fact, very few spotted cat skins can enter the U.S. legally.

Birds and Feathers -The importation of wild bird feathers, mounted birds and skins (with or without feathers) is prohibited by U.S. Law.

-Many large parrots, including certain macaws and cockatoos, are protected in their country of origin and may not be imported into the U.S. Birds originating in Australia, Brazil, Mexico, Paraguay and a number of Caribbean countries may not enter the U.S., nor may many birds of Indone­sian origin. Check carefully the legal status of colorful birds before you buy.

-Live birds, if they can be imported into the U.S., must go into quarantine under regulations of the U.S. Department of Agriculture.

Ivory -Ivory from animals, including whale, walrus and elephant, is barred from import into the U.S.

Coral -Many countries either prohibit or restrict the collection, sale and export of corals, whether in raw form or worked into jewelry.

Plants - Plants, such as cycads, orchids and cacti, are either prohibited from import into the U.S. or their import is restricted. Whether endangered or not, all plants must undergo inspection by the Department of Agriculture and be accom­panied by docu­ments certifying they are free of disease and pests.

Wildlife Curios from Mexico-Stuffed caimans, crocodiles, birds, turtles and other wildlife curios that you might find for sale in Mexico are almost certain to be confiscated by Customs or wildlife inspectors. It is best to avoid these items.
For further information regarding illegal live wildlife or wildlife products, contact TRAFFIC (U.S.A.), the Fish and Wildlife Service of the Department of the Interior, or the U.S. Embassy if you are abroad.

TRAFFIC (U.S.A.) - Trade Records Analysis of Flora and Fauna in Commerce - is a program of World Wildlife Fund-U.S. and part of an international TRAFFIC network cooperating with the International Union for Conservation of Nature and Natural Resources to monitor the international trade in wild plants and animals. Cable: PANDAFUND Telex: 64505

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