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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.

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The Key to Survival: Protecting Endangered Key Deer

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Off the southern tip of Florida lies a string of islands known as the Keys. These islands are home to a unique creature called the key deer, Odocoileus virginianus clavium, which is a subspecies of the wide spread white-tailed deer, Odocoileus virginianus. The key deer is the smallest of all the subspecies of white-tailed deer and is currently listed as endangered (Watts).

According to recent surveys key deer populations are estimated around 600-700 individuals with 75% of these located on Big Pine Key and No Name Key (Parker). These two keys happen to be the largest islands amongst the key deers current distribution, which is roughly 20-25 islands. On the outer islands populations are extremely small. For example, Howe Key is home to 15-16 deer while Ramrod Key and Water Key each have less than 5.

Key deer numbers were originally reduced by the development of the Florida keys. Today, however, the largest threat to these tiny deer are collisions with vehicles. Deer-vehicle collisions make up over 50% of all key deer mortalities (Parker 2). These collisions are being reduced however.

A project along US 1, the major roadway through the keys, was started to reduce the number of deer-vehicle collisions, 92% of which are fatal for the deer. The project created underpasses to allow the deer to travel back and forth without crossing the road and risking collisions with passing traffic. Recently a team of researchers from Texas A&M conducted a study of these underpasses and discovered these underpasses were in fact being used and had significantly reduced the number of collisions between key deer and vehicles (Parker 2). With these reductions in collisions key deer populations have increased on the islands of Big Pine and No Name keys.

Actually, the populations on these two keys have become so large they need to be reduced. Relocations to the outlying islands, which have considerably lower populations, are necessary (Parker). All of this has led to discussions of possibly reclassifying the key deer to threatened rather than endangered (Watts).

While I have yet to seen a key deer during my travels through the florida keys I am hopeful that one day I will. The North American model of wildlife conservation, a topic for future discussion, has been extremely effective in the protection and recovery of wild species. While the key deer remain threatened I trust in the model and our wildlife agencies to protect this unique animal.

References:

Parker, Israel et al. “Evaluation of the efficacy of Florida key deer translocations.” Journal of Wildlife Management. 72 (2008): 1069-1075

Parker, Israel et al. “Effects of US 1 project on Florida key deer mortality.” Journal of Wildlife Management. 72 (2008): 354-359

Watts, Dominique et al. “Distribution and abundance of endangered Florida key deer on outer islands.” Journal of Wildlife Management. 72 (2008): 360-366