May 27, 2010 § 2 Comments
Galapagos tortoises are the enigmatic symbol of the Galapagos Islands. Online readers have picked the Galapagos Tortoise as their favorite animal of these enchanted islands. For many visitors viewing these gentle giants is considered a “must” part of their vacation.
Giant tortoises first arrived in the Galapagos many millennia ago. It is thought they originated in South America and made their way across the Pacific Ocean by floating on a piece of wood. Arriving in the Galapagos the tortoises found their new home rugged and harsh, yet tortoises are able to survive long periods of time without food or water making them uniquely qualified to become the dominate grazing animal on these islands. At one time 15 distinctive sub species of Galapagos Tortoise existed – today only 11 remain.
Each of the sub species evolved differently depending on the island where they lived. You only need to take a look at a tortoise to quickly determine the type of environment existed on the island where the tortoise evolved.
Tortoises that evolved on the larger islands – like Santa Cruz or the Alcedo Volcano on Isabela benefited from the lush plant life and grew to be the largest of the species. They had plenty of food and did not need to travel great distances. They can be identified by their larger size, domed shells (making it easier to push brush out of the way) and by their shorter legs and neck.
Tortoises that came from smaller drier islands had a saddleback or flatter shell with longer legs and a longer neck making them capable of traveling greater distances. The main staple of tortoises from these areas was the pad of the opuntia cactus and the long necks allowed the tortoises to reach their meal.
Tortoises are quite elusive in the wild, and to help preserve the species the national park has made it off limits to visit many areas on various islands where the tortoises roam free. There are four islands in the Galapagos in which visitors can view tortoises: Santa Cruz, San Cristobal, Floreana and Isabela.
The most popular of these places is on the island of Santa Cruz. For visitors traveling to a Galapagos Cruise the Charles Darwin Research Station is part of every itinerary. The Darwin Station, home of the Galapagos National Park and the Darwin Foundation is the heart of the great conservation and preservation efforts being made in the islands.
Established in 1969 these organizations quickly realized that the remaining species of tortoises were all endangered of becoming extinct. They rapidly set up a tortoise breeding and rearing program in order to protect and repopulate the species. Tortoises were transported from their island to pens at the Darwin Station where they were able to breed and their eggs. The eggs were put in incubators where they could hatch without the concerns they would have in the wild.
During early years of life, young tortoises are in constant danger primarily from introduced species. Rats feed on tortoise eggs. The shells of hatchlings are fragile and the hooves of feral goats and donkeys can easily damage the shell and kill young tortoises. At the breeding center, there are pens for tortoises of different ages allowing them to develop without these threats until they were old enough and their shells strong enough to be released back into the wild.
The most famous resident of the Darwin Station is Lonesome George. Discovered in 1971 George is noted as the last remaining tortoise on the island of Pinta. A rather flat island, it was a favorite place for passing boats to fill their hulls with fresh tortoise meat. At the time George was discovered it was thought his species was extinct. Scientists were delighted to have found a remaining tortoise and plans began right away on how best to help George and his species survive. Having him remain on Pinta had complications as feral goats overrun the island and were devastating the island’s vegetation and limiting the food supply available for George. The solution was to move him to the Darwin Station, which would provide a safe haven while they searched for a mate and way to continue his line.
Traveling to the highlands of the island is the best place in Galapagos to see these tortoises roaming free. From June to December during the dry cooler months the tortoises travel to the highlands in search of the area’s water and juicy plants. During these months the tortoises can be found in the area near Santa Rosa. The tortoises mate and then the female tortoises depart to lay their eggs. Male tortoises remain here year round enjoying the muddy water of the lagoon and the many plants in which to eat.
On the island of San Cristobal, visitors can travel to the highlands to visit Cerro Colorado a recently built tortoise reserve not far from El Junco Lagoon. Tortoises of San Cristobal were endangered from feral animals, so the tortoise preserve was established as a walled area that protects them from other species. Coming here visitors can enjoy a stroll along the boardwalks and grated trails seeing San Cristobal tortoises, local plants and a variety of birds including the endemic Chatham Mockingbird, Yellow Warbler and Darwin Finch.
Making your way to the island of Floreana provides yet another opportunity to view San Cristobal tortoises. Floreana was a favorite island of sailors and as tortoise meat was an easy supply of food that would last for months on board their ships, Floreana Tortoises were collected to a point of extinction. In a rock wall area in the highlands of Floreana you’ll find the tortoises that were brought here by members of the Wittmer Family (who built a small hotel on the island). The tortoises were viewed as a way to encourage visitors and they were left to roam the grounds of the hotel for the enjoyment of tourists. As the tortoises were not natural to the islands and are considered now to be a mixed breed rather than pure-breed the National Park Service established a tortoise pen in the highlands of Santa Cruz where these tortoises can be seen today.
Isabela is my favorite place to see Galapagos Tortoises. The largest of the islands, Isabela is home to 5 distinct sub species of Galapagos Tortoise. The National Park and Darwin Foundation set up a breeding center for Isabela tortoises just outside the town of Puerto Villamil. A nice walk passing by flamingo lagoons takes you to this the tortoise center where you can see several species of tortoise next to each other. It’s here where you can best identify the environment in which the tortoise evolved by looking at its size and the shape of its shell.
The tortoise breeding programs both on Santa Cruz and on Isabela have been very successful. Many of the tortoises from both programs have been released into the wild allowing them to live the lives they were meant to live. On Isabela you can see these newly free tortoises ranging in age from 5 years to 25 years roaming free in an area near Wall of Tears. Walking along the paths through the mangroves you can encounter these future giants walking along eating the smaller plants and enjoying the waters of small pools.
Read our blog on Galapagos Tortoises and the Evolution of Extinction
April 16, 2010 § 1 Comment
The southernmost island in the Galapagos Archipelago is also one of the most interesting to visit. The incredible concentration of wildlife found on Española makes it a favorite of tourists and guides alike and each April the Albatross return and make the experience complete.
The Galapagos Islands are volcanic in origin and were never connected to the mainland. Rather each island was born at the Galapagos “Hot Spot” a point deep under the sea where energy from the divergence of the Nazca, Cocos and Pacific plates is released in the form of magma, built up overtime this magma forms sea mounts which rise out from the ocean to form islands. Over time as the plates continue to shift the islands break free and a new island is born and an archipelago is formed.
Española is a classic example of a shield volcano and the aging process of the islands. The oldest of the islands at approximately 3.3 million years, Española was formed from a single caldera in the center of the island. As the island moved further and further from the hot spot the volcano became extinct. When islands are younger and more volcanically active (like Fernandina to the west) the island is stark made up of lava and sand, plant life is limited to pioneer plants and wildlife found on the island are those that can survive the harsh environment and rely on the seas for food. In contrast on Española as the island moved further and further away from the hot spot the lava fields begins to erode and were replaced by fertile soils. This soil was able to sustain plants and in turn wildlife. The remote location of Española allowed these life forms to evolve overtime independently of the other islands in the chain and today Española is home to a large number of endemic animals.
The Hood Mockingbird is one such example and endemic to the island. These brazen birds have no fear of man and frequently land on visitor’s heads, shoulders, feet or anywhere else they can searching for food and water. The Hood Mockingbird is slightly larger than other Mockingbirds found in the Galapagos; its beak is longer and has a more curved shape. It is the only carnivorous mockingbird and feeds on a variety of insects, turtle hatchlings and sea lion placentas.
Home to three species of Darwin Finch the large cactus finch, small ground finch and warbler finch can all be found. For those who read about the Galapagos one of the better known inhabitants is one that you will never see – the Española Tortoise. In 1965, the tortoise population on Española had been reduced to just 12 females and 2 males all of which were transferred to the Darwin Station on Santa Cruz. In 1976 another male was found at the San Diego Zoo and transferred to the Galapagos to join the breeding program. The first great success of the tortoise breeding and rearing program, in 1991 tortoises were repatriated to Española and today there are more than living in a protected environment near Manzanillo Bay.
Española offers two visitor sites each with a very different experience, the beach at Gardner Bay and the Rocky Cliffs and wildlife of Punta Suarez.
On the northern coast is Gardner Bay, consisting of two long stretches of beach the sites main attraction is the sea lion colony that has found the powdery white sands the perfect place to take a never-ending siesta. Gardner Bay is one of the few open areas within the national park where visitors are free to explore on their own, as long as they keep an eye out not to step on any sea turtle nest.
The snorkeling at Gardner Bay is fantastic. Close to the beach you can swim with sea lions this is an opportunity not to be missed. Further out towards Tortuga Rock and Gardner Island schools of large colorful tropical fish including yellow tailed surgeon fish, angelfish and bump-head parrot fish swim along with an occasional Manta Ray gliding by and white-tipped sharks napping on the bottom.
On the western tip of Española is Punta Suarez one of the best sites in the Galapagos. The amount of wildlife is overwhelming. The walk is approximately 2 hours and during mating season Punta Suraez comes to life as one big party.
Arriving on shore you are met by carefree sea lion pups waiting to entice you back into the water. Colorful marine iguanas are waiting along the walkways and scattered in the rocks. Normally marine iguanas are black in color, a natural camouflage, making it difficult for predators to differentiate between the iguanas and the black lava rocks where the iguana’s live. The subspecies found on Española appear to be almost festive; these iguanas which are normally a reddish shade turn green during mating season.
Continuing inland Galapagos Doves peck around seemingly unaware of your presence, finches fly back and forth between bushes and Galapagos Hawks are seen perched waiting for their next meal. Here masked and blue footed boobies dance with their partners. Masked boobies flapping their wings as the blue-foots strut around their bright feet honking and whistling as if they each have their own party noise maker. Young boobies appear to be in costumes as their downy feathers look like wig on their otherwise naked body.
The trail leads to the cliff’s edge where a fissure in the lava below creates a dramatic blow-hole forcing the sea water over high in the air as if it were liquid confetti. These cliffs are an excellent place to watch what seems to be a magic show, swallow-tailed gulls and red-billed tropicbirds levitated by thermals perform stunts overhead.
If wildlife is the highlight of Española than the Waved Albatross is the star of the show. Known as endemic to the island Española is their only nesting place. Albatross arrive on Española each April and remain here through December. The island’s steep cliffs make perfect runways. These large birds seem somewhat awkward on land as they spread out their expansive wings and run launching themselves off the cliff’s edge. Once in the air these large birds with their 6-foot wingspan seem transformed as they gracefully soar in the wind. Española is the only island where you are guaranteed to see albatross in Galapagos.
Española can only be visited as part of a naturalist cruise, and visiting Española is sure to be a highlight of your trip. Make sure to have you camera batteries fully charged and plenty of space on your memory card because you’ll want to take lots of pictures!
March 19, 2010 § 4 Comments
When you think of Galapagos, the first two thoughts that come to mind are Charles Darwin and giant tortoises. The giant tortoise is the iconic symbol of these islands. The name Galapagos come from a Spanish world for saddle – referring to the shell of these gentle giants. The national park uses an image of the giant tortoise as its logo. Whenever you see information about the Galapagos – you see pictures of the beloved giant tortoise.
The world’s largest tortoises, Galapagos Tortoises have a lengthy 150-year lifespan. Male tortoises are known to grow to be over 600 pounds. The archipelago was never attached to a continent and all the plants and animals, which arrived in the Galapagos, did so by either swimming, flying or floating. The journey across the ocean was too difficult for grazing mammals that dominate the grasslands of other parts of the world, and thus the slow moving tortoise reigned as king for thousands of years.
At the time of Charles Darwin’s visit in 1835, it was thought that 250,000 tortoises and 12 subspecies existed here. It was the comments regarding the tortoises from the local vice-governor, which first dismissed by Darwin, would later come to inspire him:
“I have not as yet noticed by far the most remarkable feature in the natural history of this archipelago; it is, that the different islands to a considerable extent are inhabited by a different set of beings. My attention was first called to this fact by the Vice-Governor, Mr. Lawson, declaring that the tortoises differed from the different islands, and that he could with certainty tell from which island any one was brought. I did not for some time pay sufficient attention to this statement, and I had already mingled together the collections from two of the islands. I never dreamed that islands, about fifty or sixty miles apart, and most of them in sight of each other, formed of precisely the same rocks, placed under a quite similar climate, rising to a nearly equal height, would have been differently tenanted; but we shall soon see that this is the case. It is the fate of most voyagers, no sooner to discover what is most interesting in any locality, than they are hurried from it; but I ought, perhaps, to be thankful that I obtained sufficient materials to establish this most remarkable fact in the distribution of organic beings.”
Darwin and his shipmates aboard Beagle viewed tortoises much in the same way as the pirates and whalers, tortoises were something to be exploited. The members of the Beagle harvested 30 tortoises from the islands, which they ate on their way home.
Over the past few centuries the systematic harvesting of tortoises for meat, oil, as well as the introduction of new species dwindled the population down some 90% from what it was in during Darwin’s visit. Both the Floreana and Pinta tortoises are noted as extinct and all of the remaining 10 species of Galapagos Tortoise are listed as endangered species.
In 1959, 100 years after the first publishing of Darwin’s On the Origin of Species the Galapagos Islands became as a national park. The park service together with the Darwin Foundation has made remarkable steps over the past 50 years towards the preservation, conservation and restoration of native species.
Perhaps the best example of their efforts is the story of the Espanola tortoise. At one time there were at least 3000 native tortoises on the island of Espanola. However Espanola is one of the flattest and most accessible of the islands, making it a favorite place for passing ships. As a result by 1965 there were just 14 remaining tortoises living on Espanola – 2 males and 12 females. The tortoises were transferred to the Charles Darwin Research Station on Santa Cruz. A third male was then discovered at the San Diego Zoo. In the 1970’s the tortoise-breeding program began. From the brink of extinction, of 15 tortoise the program has been a success and today nearly 1500 Espanola Tortoise have been repatriated to their native island.
With the success of the Espanola program stopping the extinction of other species proved to be more problematic. In 1971, Lonesome George was discovered on the Pinta. He has the unique distinction of being is noted as the last remaining of his species. George was relocated to the Darwin Station and scientists began work on the question how to keep the Pinta Tortoise from becoming extinct. Two females from Wolf Volcano on Isabela were placed in the pin with George. These females were selected as they were found to be the genetically closest relation to George and though any off spring produced would not pureblood – the species would some how continue.
For years George showed little or no interests in these females. But in 2008, the national park announced both of Geroge’s companions laid eggs. The world awaited news if the Pinta race had been saved. At the end of the year it was announced none of the eggs were viable and their search for how to save the species continued.
In 1994 a team of Yale Scientists began the Galapagos Tortoise Genetics Process. The group went to Isabela and took blood samples from 27 tortoises living high on the Wolf Volcano. Some 2000 tortoises are thought to live in and around Wolf. These tortoises are of significant interest, as tortoises here, resemble more than one subspecies. Normally each group of tortoise will either have a domed shaped shell (similar to the tortoises of Alcedo or other parts of Isabela) or a saddleback shaped shell (similar to Lonesome George) depending on the environment where they live. Yet near Wolf, tortoises can be found with both domed and saddleback shells.
Over the next decade the genetics team began collecting DNA samples from the tortoises in not only in Isabela, but also began samples from tortoises at the Darwin Station, around Galapagos, and tortoises held in captivity all over the world. On Pinta they found they took DNA samples from the remains of 15 tortoises and they cataloged the information to gain a better understanding of the species.
As they began to review their database, the impossible seemed to be possible. First they believe they have discovered a second pureblood Pinta tortoise. A Tortoise known as Tony, thought to be approximately 50 years of age is living at the Prague Zoo – from all current data Tony appears to be the same exact subspecies as George.
As they sifted through the DNA information they discovered the reason the Wolf tortoises appeared to resemble more than one subspecies. Isabela and the area near the Wolf Volcano was often the last stop for pirate ships in Galapagos. It appears that these ships collected tortoises on other islands during their stay only to discard them here. When testing the DNA samples, several of the tortoises living on Wolf were found to be first generation hybrid Pinta tortoises – tortoises born to mothers from Isabela and fathers from Pinta. This discovery meant that some of the tortoises living on Wolf were 50% the same genetic subspecies as Lonesome George. This information provided new hope that by further investigation a pureblood or half-blood female Pinta tortoise can be found – and the Pinta race can survive.
The genetic team seemed to have uncovered a miracle – still there were more surprises to realize. The research discovered descendants of the extinct Floreana Tortoise. The Floreana subspecies became extinct during the early 20th century due to human activities, and unlike Lonesome George no known examples were known to have survived. Yet, the DNA research uncovered 9 tortoises with high percentage of Floreana genome (up to 94%) and they believe 1 tortoise may even be pureblood. Of the tortoises identified of being from Floreana 6 are female and 3 are male all of which are currently residing at the breeding center in Santa Cruz.
Drawing from the success of the Espanola breeding program these new findings of the Genetics team, man may now be able to make up for some of their previous wrong doings. What was once extinct may not be extinct in the future. It’s all just a matter of time with the help of science and mother nature.