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Darwin Was Right: Island Animals Are Tamer – Yahoo News

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Darwin Was Right: Island Animals Are Tamer – Yahoo News.

New River Monster Discovered in Brazil – Yahoo News

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New River Monster Discovered in Brazil – Yahoo News.

Hummingbirds

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Many people enjoy watching hummingbirds. All across the US one can find hummingbird feeders in any neighborhood throughout the spring and summer. These tiny birds (which are only found in the western hemisphere) are not only fun to watch, they are fascinating creatures in how they have adapted to the challenges of life.

Throughout the eastern United States the most common hummingbird is the Ruby-throated Hummingbird. The mature males have a brilliant reddish/orange throat patch. These birds winter  along the northern edge of South America. The most amazing part of this is that recent studies have found these tiny birds actually cross the Gulf of Mexico. In fact these amazing critters can carry enough fat to travel 1000km in 26 hours. This is more than enough to cross the Gulf unaided and travel several miles inland before stopping to refuel.

Ruby-throated Hummingbird

Ruby-throated Hummingbird

Another North American species that conducts extreme migrations is the Rufous Hummingbird. These birds are debatably the champions of long distance migration, migrating 3900 miles each way between Alaska and central Mexico. While they are by no means the champions in terms of distance they are certainly the champions in terms of body lengths. These birds travel over 78 million times their own body length, where as the Arctic Tern (the champion in terms of distance) only travels 51 million body lengths.

Rufous Hummingbird

Rufous Hummingbird

As hummingbirds are a family of birds only found in the western hemisphere I would be remiss to not mention a South American species. Especially since South America has far more hummingbird species than than North America (compare ~150 species in Ecuador alone to only 18 species throughout all of North America, including the tropical climates of central American countries).

Probably the most impressive species from South America is the Ecuadorian Hillstar. These amazing little birds live at the highest elevations for any species of hummingbird. Found in the Andes Mountains of Ecuador, these birds live between 3,500 and 5,200 meters (11,500 to 17,100 feet) above sea level. These birds face great energy demands. Living at such high elevations nights can be freezing, and as hummingbirds they naturally have high metabolisms and body temperatures. If they were to maintain these body temperatures over night, when conditions are often freezing, they would quickly burn their energy stores. However, these birds have evolved to enter a state of torpor overnight in which they lower their core temperature to decrease the difference between their body temperature and the environment. This adaptation allows them to burn much less energy to keep their core body temperature steady. The next day they will increase their body temperature and metabolism and resume normal behavior. This amazing behavior has allowed them to thrive in an extreme environment.

Ecuadorian Hillstar

Ecuadorian Hillstar

The Stinky Turkey: Hoatzin birds

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Hoatzins were possibly the most unique bird species I observed during my time in Ecuador. This species seems to have branched off from other species of birds very early in history. They have a prehistory look to them and links to other species have not been found. As such they have been placed within their own family of birds. These are a unique species of tropical birds found in rain forests. Known as stinky turkeys, these birds have developed a unique strategy for surviving in a harsh environment.

While most of the vegetation biomass of the Amazon rainforest is tied up in tree leaves, many animals are unable to survive on these as they are hard to digest and often contain toxins. Hoatzins however are folivores, meaning they eat only leaves. While some mammals have also developed this diet,this dietary behavior is especially unique amongst birds. They are the only bird species known to use foregut fermentation (like cattle). This adaptation is necessary to digest the leaves they feed on. As a result of this diet they have a distinct odor often compared to fresh cow manure due to this fermentation process.

Another unique adaptation is found in their nestlings. As these birds live in an environment that is full of predators they need some way to evade them while they are still to young to fly. These birds live near water bodies and  often their nestlings will fling themselves into the water to evade predators. This is not an act of suicide though. The nestlings possess claws on their wings which they use to hook on limbs and climb back out of the water and into their nests.

Hoatzin along Napo River, Ecuador

Hoatzin along Napo River, Ecuador

Scientists: Galapagos tortoise can be revived – Yahoo! News

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Building off of my post about the Galapagos I have found an interesting article related to Galapagos tortoises.

Scientists: Galapagos tortoise can be revived – Yahoo! News.

Wildlife of the Galapagos Islands

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As a wildlife ecology student my recent trip to the Galapagos Islands was the experience of a lifetime. I was so pumped about the trip that I even read Darwin’s “Origin of Species” (it was rough). From the moment I set foot in San Cristobal, my point of entry, I was completely blown away. My expectations for the trip had been surpassed within the first hour in the archipelago.

As soon as I had cleared through customs I spotted my first Magnificent Frigatebird and a couple of Blue-Footed Boobies. My first sighting of a Darwin Finch was on my way to meet up with my local guide. I felt like I was treading in the footsteps of Darwin himself as I observed the magnificent variety of bird life all around me. As my guides described it to me, the Galapagos do not have a huge diversity of species like I had seen on the mainland, but those species found in the islands are found in abundance. Imagine colonies of 70 or more Blue-footed Boobies or 400 sea lions laying on the beach.

One of Darwin's finches

One of Darwin’s finches

The most amazing characteristic of the wildlife I found on all of the islands I visited was their complete lack of fear. It was not uncommon to see a sea lion flop down on a bench next to a human. During my snorkeling trips I came face to face with Galapagos Penguins, sea turtles, and Galapagos sharks and none of them cared I was there. Sea lions would swim up to me and start trying to play by spinning in the water and bumping into me. However this lack of fear is not the result of taming or acclimation to human presence. The Galapagos do not have any large, terrestrial based, predatory mammals that are native to the archipelago. As such the animals do not see humans as a threat.

Sea lion on a bench

Sea lion on a bench

Along with some amazing photography opportunities due to this lack of fear I also had the opportunity to observe the effects of isolation and evolution. The greatest example of this were the mockingbirds I observed. The mockingbirds of the Galapagos originally evolved from a mainland species that somehow migrated to the islands. Over the years of isolation they have become genetically distinct from mainland mockingbirds. They have evolved into their own unique species, the Galapagos Mockingbird. I observed this species during my travels on Santa Cruz and Isabela. Speciation has continued with those mockingbirds found on San Cristobal though. Again they have evolved into a species of their own known as the San Cristobal Mockingbird.

San Cristobal Mockingbird

San Cristobal Mockingbird

Another great example of evolution within the species of the Galapagos is amongst the tortoises. Currently there are 11 species of Galapagos tortoises located on different islands throughout the archipelago (there were 15 species at the time of Darwin’s visit to these islands). These species are not only genetically distinct, some have developed unique shell shapes as an adaptation to conditions on their individual islands. The carapaces (shells) of tortoises on the islands I visited all had the common dome shape. However, on some of the islands like Española, which are arid and have little low lying vegetation, tortoises have developed saddle-shaped carapaces. This shape allows them to stretch their necks higher up to feed.

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  Galapagos Tortoise with domed carapace       Galapagos tortoise with saddle-shaped carapace

Galapagos tortoise with saddle-shaped carapace

Unfortunately I was unable to see the Flightless Cormorants (with no land based predators and a diet composed of fish flight is an unnecessary expenditure of energy and has thus been lost) during my visit to the Galapagos. However the trip was still an amazing experience, especially for a wildlife ecology student such as myself. Although they are somewhat difficult to get to the Galapagos Islands are an amazing destination and I would highly recommend them as a destination for nature enthusiasts.

Ecuador: A birder’s paradise

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From the viewpoint of a birder  Ecuador is paradise. In size Ecuador is roughly as  large as the state of Colorado, yet it has almost 1000 more species than the entire US. While the US has only around 500 species that are regulars (not counting odd migrants that have drifted off course), Ecuador has over 1500. According to the birding field guide released by National Geographic the entire continent of North America only has 990 species.

Not only does Ecuador have an incredible variety of birds in such a small area they have an excellent infrastructure to allow birders to quite easily visit all the different ecosystems the country holds. In a matter of two weeks I visited the Amazon rainforest, the Andes Mountains (around Cotopaxi National Park), the cloud forest on the western slopes of the Andes, and finally did some island hopping through the Galapagos. Aside from the Galapagos most of these regions are no more than a half day drive from Quito, the capital of Ecuador and main port of entry for foreign visitors.

Flame-rumped Tanager

Flame-rumped Tanager

As this trip was for a class most of my time was strictly scheduled and I could not break out and do some hardcore birding. Even so, on only three occasions dedicated strictly to birding and incidental sightings as we traveled, I picked up almost 100 new species for my life list. Some birds such as the hummingbirds and tanagers I saw displayed beautiful vibrant colors. Others, like the Hoatzins have developed unique adaptations to survive in their ecosystems. In fact the Hoatzins will likely be the focus of a later post.

In the Amazon I saw such species as Hoatzin (these strange looking birds feed entirely on leaves), an Anhinga, Blue-headed Parrots, Cocoi Herons and many more. These birds were mainly spotted as we were traveling from one activity to another, typically along the Napo River.

Hoatzin

Hoatzin

My only days of official birding on the Ecuadorian mainland occurred in the cloud forest at the Inti Llacta reserve and in the paramo (high mountain grasslands in the Andes) outside of Cotopaxi National Park. In the cloud forest I saw my first trogon, the Masked Trogon, Flame-rumped Tanagers, and almost a dozen species of hummingbirds including a Tawny-bellied Hermit and Booted Racket-tail. Up in the Andes I saw species such as Rufous-crowned Sparrows, Andean Lapwings, and Tyrian Metal-tails.

The Galapagos Islands provided some of the best birding opportunities. While they do not have as much diversity as the mainland, they have far greater concentrations. It was not uncommon to find Blue-footed Boobies in groups as large as 30-50 members. Not to mention Darwin’s finches which seemed to be chirping from every tree or window sill. And who could complain about snorkeling with Galapagos Penguins?

Blue-footed Boobies

Blue-footed Boobies

I would highly recommend Ecuador and the Galapagos to any nature lovers, but especially to birders. With such great variety of species in such a small area birders will think they are in heaven. Not to mention that the tropical climate and welcoming atmosphere make Ecuador a true paradise.

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