Area Size: 4588 Km²
Maximum Altitude: 1707 meters / 5599 feet

Island Highlights: Sierra Negra Volcano, Los Tuneles, Puerto Villamil, Punta Vicente Roca, Tagus Cove, Elizabeth Bay, Urbina Bay, Punta Moreno, Punta Albermarle, Flamingo, Mangrove Finch, Giant Tortoise, Flightless Cormorant, Galapagos Penguin, Giant Manta Ray, Las Tintoreras, White Tip Sharks, Los Gemelos, Wall of Tears, Land Iguana, Marine Iguana, Pacific Green Sea Turtle

Introduction

Isabela is situated on the western edge of the archipelago close to the Galapagos tectonic hot spot. It is the largest and consequently most diverse island in terms of wildlife and marine life. She is 4 times larger than the second largest island of Santa Cruz. There is a huge amount to see on this island, both in terms of wildlife and scenery.  Aqua-Firma can take you some of the best of these by small boat, biking, snorkelling and a combination of 4WD and trekking. Other sites can only be accessed by live aboard boat.

In the shape of a seahorse, Isabela is approximately 1 million years old, making her one of the youngest Galapagos islands. With 5 of out of 6 of her volcanoes still active, Isabela is one of the most volcanically active places in the world.

Puerto Villamil is the third largest human settlement in the archipelago and is located on the south eastern tip of the island. It is considered to be the most attractive town of the Galapagos archipelago and is characterised by its long sandy beaches. It is a lovely place to spend a few days, whether just to relax or as a point from which to explore the island and its coastline.

It is very clear when you visit Isabela that its landscapes are moulded by volcanic activity. If you fly in, then you will see beneath you Turtle Island, which is a volcanic cone, of which about one third has collapsed out of sight into the sea. As you fly over Isabela's southern land mass, its surface takes the form of molten lava which has dried suddenly, maintaining the appearance of a thick flowing liquid. It is difficult to find anywhere on the island or its coast where you can't see at least one of its volcanoes.

The coast of Isabela is rich in marine life. The western coastline is known for upwellings produced by the Cromwell Current. The nutrition this brings helps to make it a good place to spot whales such as the southern right whale, humpback whale, sperm whale, minke whale and orca. The north eastern coast is often good place for seeing Giant Manta Rays, as is Los Gemelos in the south - a coast which is excellent for marine iguanas, white tip sharks, Pacific Green Turtles and more.

Aqua-Firma explores Isabela Island in three main ways. Some of our Wildlife Yacht Safaris explore the coast of Isabela for as much as two whole days, with opportunities to walk inland and snorkel. Please check with us which of our itineraries go there.

For those who prefer to be land-based, or particularly enjoy snorkelling, trekking and mountain biking, we can take you to explore the southern part of the island in detail. Highlights include opportunities to sea flamingos and a day trek to the peak of the Sierra Negra Volcano whose 6 mile wide crater provides one of the best opportunities to see far across Isabela and its neighbouring islands. The stunning islets of Las Tintoreras and Los Tuneles are highlights in the south where we can see white tip sharks at the sea surface, Giant Manta Rays and marine iguanas whilst snorkelling, Galapagos penguins and a host of other marine life and coastal birdlife.

For keen divers, some of our dive liveaboard trips encompass Cabo Marshall which is the best place in the islands to dive with Giant Manta Rays. Punta Vicente Roca is another great dive spot which has only recently come back onto liveaboard itineraries.

Wildlife

Punta Vicente Roca, located in the north eastern tip of Isabela, comprises the remains of an ancient volcano which has formed an enclosed bay, free from rough ocean swells. This hidden gem is an idyllic anchorage and is a fantastic place to explore, both above water and by snorkelling. An array of birdlife can be spotted here, including Nazca and Blue-footed Boobies, Flightless Cormorants and Brown Noddy Terns.

The sheltered waters of Tagus Cove provide ideal conditions for a dinghy ride, which will inevitably provide encounters with flightless cormorants, penguins and pelicans.

Isabela presents fantastic opportunities for bird spotting, with the possibility of seeing American flamingos, lava herons, Galapagos doves, dark-billed cuckoos, Galapagos mockingbirds, ground finches and mangrove finches. Thousands of red-necked phalaropes can be seen on the island, as well as smaller numbers of red phalaropes.

The steady increase of human activity on Isabela is almost certainly accountable for the introduction of a new frog (Scinax quinquefasciata), that has recently been found living on the island. Usually found in the coastal lowlands of Ecuador, the presence of this frog on Isabela is somewhat unwelcome. Little is known about the frog's biology, thus population control methods have proved to be problematic.

Over the past few years, Isabela has played host to some surprisingly late discoveries of new species of wildlife. This has included a new species of land iguana called the Pink Iguana (Conolophus subcristatus rosada), so called because of its colouration. It was first seen by rangers in 1986 by park rangers living around Wolf Volcano - an area which is difficult to visit on land and a place where Aqua-Firma can only explore along the coast. Scientists began to research the pink iguana in more detail in 2000 and calculated that it split genetically from other volcanoes about 5.7 million years ago. It is estimated that there are just 100 alive which means that it is classified under CITES as Critically Endangered.

The yellow iguana was assumed to have been wiped out in Isabela by dogs and other foreign invaders many years ago, but this was re-discovered at Punta Garcia.

Other largely unexplored and forgotten areas of Isabela have recently yielded a wealth of new wildlife discoveries. The lakes contained within the caldera of Cerro Azul, one of the world's most active volcanoes, have been shown to harbour a remarkable array of aquatic life. New species have included groups of nematodes, beetles and dragonflies. Meanwhile, new species of insect continue to be discovered, particularly on the slopes of the northern volcanoes. In 2008 it was discovered that a moth assumed to be just one species, was in fact two: one which inhabits the low arid zones and the other that resides in the elevated areas of Isabela.

Urbina Bay is a seasonal nesting site for much of Isabela's wildlife. In the wet season, giant tortoises journey to the bay to lay their eggs in the sand, before migrating back to the highlands when the lowlands turn dry. A short nature trail here leads to a reef of dried coral heads, molluscs and other organisms, which serve as evidence of a geological uplift from the sea that occurred in 1954. Marine iguanas and flightless cormorants can often be spotted here. Further along the coast at Elizabeth Bay, the extremely endangered mangrove finch can sometimes be seen, which makes this is a popular stop for birdwatchers.

The largest population of giant tortoise in the Galapagos inhabits the grassy slopes around the rim of the Alcedo volcano. Here the tortoises amble steadily along, whilst grazing in the short turfs, then in between meals sit almost motionless, leisurely watching the world go by. The necks of these tortoises are proportionally longer than those of other giant tortoise species, meaning that they are vulnerable to predators as they cannot withdraw enough of their flesh into their shells. Fortunately, Isabela is free from such predators as cats and dogs, so the lack of security that their shells provide is inconsequential. Nevertheless, these shells can at times be problematic for the tortoises. It is almost impossible for the tortoises to rid themselves from pesky skin parasites and ticks, thus they require the assistance from other resident wildlife, of which mockingbirds are always keen to oblige. By way of summoning the mockingbirds, the tortoise raises itself onto its feet and extends its neck. This change in posture is a signal for the mockingbirds to begin their parasite removal service, which they carry out by hopping around the tortoise's skin folds and shell cavity.

Punta Moreno, situated on the western shore of Isabela is a unique location, comprising an array of Galapagos's most spectacular wildlife and fascinating geological detail. The beautiful rocky shoreline is often frequented by Galapagos penguins and other shore birds. A path leads through incredible jagged lava rock formations which encapsulate craters and crystal tide pools, many of which are surrounded by mangroves. Such geological formations provide the ideal habitats for such colourful birdlife as pink flamingos, blue herons, brown pelicans and Bahama pintail ducks. These artfully formed lagoons often present the occasional green sea turtle, white-tipped shark and puffer fish.

Marine Life

Marine life is bountiful all around Isabela Island. In the far South West at Los Tuneles, there are some mangrove and lava tunnel systems where we have great opportunities to snorkel with schools of Golden Cownose Rays, White Tip Reef Sharks and Green Turtles.

The west coast of Isabela usually provides the best opportunities for seeing whales in the Galapagos. Two ocean currents collide here: the Humboldt and the Cromwell (also known as the Equatorial Counter Current), creating the coldest water temperatures. Marine mammals seen in this area can include sperm whales, pilot whales, orcas and even a rare sighting of a blue whale. Several of our Wildlife Yacht Safaris reach these areas, so if this is an area you would like to visit, please contact us for advice.

Elizabeth Bay is the deepest inlet into the west coast of Isabela - a place where we make a wet landing to go onshore. This is where we can find the largest concentration of Galapagos penguins in the Galapagos, which we can spot along the shorelines of the Mariela Islets. Galapagos Hawks are often spotted circling overhead in this area, while schools of pompanos and dorados can be seen when snorkelling below. This is also a great spot for seeing Black or Pacific Green Sea Turtles, which are most commonly spotted from November to February.

A trip along the Bolivar Channel will lead to Tagus Cove, which historically speaking was a popular anchoring site for pirates and whalers. It is also a good for seeing dolphins and whales.

For divers, our main focus by liveaboard is Cape Marshall (Cabo Marshal in Spanish). Here we find cleaning stations for Giant Manta Rays, around seamounts whose peaks are no more than 6m below the surface. Volcanic ash runoff can reduce visibility here which means when you do see a manta, you are close enough to take in its full scale. Sometimes we can also see huge schools of Black Striped Salema which are a particular favourite of fur seals and sealions - something else you can enjoy with some playful encounters along the coast here.

One of the best dive sites of the Galapagos is that of Punta Vicente Roca: a label which can be attributed to a combination of cold water currents and the protective nature of the cove formation.  The dive site lies beneath a pretty cove, which is itself lies beneath the eroded remains of a volcanic cone.  The underwater surroundings of the dive site mirror the landscape of hills and deep crevices above.  The walls are decorated with an array of corals and overall it is an extremely colourful site, although the waters here can at times be breathtakingly cold.  Such marine life that is likely to be seen here, includes the Galapagos shark, Galapagos rock bass, gold-rimmed surgeonfish, the unusual harlequin wrasse and sailfin grouper.  Huge schools of Black Striped Salemas can also often be encountered here.

Conservation Issues

Puerto Villamil remains a small and relatively sleepy village, but the balance between conservation and human exploitation of the island's resources represents one of the most significant challenges to Isabela's biodiversity. Although prohibited since 1933, the consumption of tortoise meat is still an ongoing problem on Isabela. 190 giant tortoises were killed throughout the Galapagos between 1995 and 2004, the majority of which resided on Isabela. These statistics have prompted a need to encourage local people from a young age about the benefits of conservation.

Human settlement of Puerto Villamil has brought with it an invasion of goats, cats and dogs. When homeless animals go feral, they carry with them diseases which pose a tremendous threat to much of Isablea's treasured wildlife. Not only that, but they are also responsible predating the eggs of local wildlife. The idyllic site of Punta Moreno has even seen attacks by dogs on sealions and marine iguanas.

Two species of Isabela's bird population have recently brought cause for concern. The flamingos, which are most commonly seen wading in the brackish ponds, have steadily shown a decline in their population. The most likely cause has been the flooding of nesting sites brought about by recent El Niño and tsunami events. Unfortunately, such events are likely to increase with the continuing effects of climate change.

Mangrove finch populations have also been dwindling over recent years. There are an estimated 100 individuals left on Isabela, divided between two mangrove forests. The main threats to the finches are introduced brown and black rats, smooth-billed anis, fire ants and parasitic flies. Depending on how much more their population deteriorates, it may be necessary to bring all remaining mangrove finches into captivity.

Isabela's Giant Tortoise Breeding Centre

Isabela is the only Galapagos island where several species of tortoise can be seen together. The distance between the volcanoes and the diversity in environment and habitat has been fundamental in enabling the tortoises to evolve. A short 20 minute from Puerto Villamil is the Giant Tortoise Breeding Centre. The centre provides opportunities to see tortoises at all different stages of their development, from eggs to small hatchlings; and juveniles to sub adults. The centre works to protect and increase the population of the five subspecies of giant tortoise that reside on the island, with the ultimate aim of releasing them back into their natural habitats. We can often find reintroduced tortoises on our land based programmes on Isabela.

One of the most important functions the Breeding Centre serves is to protect newborn tortoises from introduced fire ants. Tortoises are defenceless against these ants which can kills tortoises younger than about two years old. Fire ants are widespread throughout the Galapagos and it only on Wolf Island where they have so far been painstakingly eradicated. The chances of achieving this on Isabela seem pretty much impossible.

Another function of the Centre is for rehabilitation of tortoises threatened by volcanic eruptions and forest fires.

Geology

Isabela is renowned for being of substantial geological interest. She provides brilliant examples of the geologic events which occurred to form the Galapagos islands, including uplifts at Urbina Bay and the Bolivar Channel; and tuff cones at Tagus Cove. The Sierra Negra volcano has a cone second only in circumference to the Ngorongoro Crater in Tanzania. It last erupted in  and famously captured in 2005 whilst the BBC were filming the mini series Galapagos. Aqua-Firma can take you trekking around the perimeter of the main crater and across areas still hot just beneath the surface lava where it last erupted.

Isabela was formed approximately one million years ago with the merger of six shield volcanoes: Alcedo, Cerro Azul, Darwin, Ecuador, Sierra Negra and Wolf, in which all, with the exception of Ecuador, are still active. Ecuador and Wolf lie directly on the Equator, with Wolf being not only the youngest of the islands' volcanoes, but also the highest point in the Galapagos archipelago.

The landing site at Tagus Cove leads to up a wooden stairway to a nature trail to reach Darwin Lake. This is a perfectly formed circular salt water crater. The trail then leads to a promontory, formed by spatter cones providing a spectacular vantage point to observe both Darwin and Wolf volcanoes.