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The Galapagos Islands – Exploring and Preserving Its Uniqueness Presenter: Patricia L. Rahn, Omicron Chapter, New Jersey Delta Kappa Gamma International Convention Chicago, Illinois Summer 2008
In 2004, my husband and I took a trip of a lifetime to the Galapagos Islands, 600 miles off the coast of Equator. Our trip started in Quito, the capital. We flew over the Andes Mountains to the coast of Ecuador for the 600 mile flight. We traveled on Celebrity Cruises. If you love wildlife and pristine nature, consider a trip to the Galapagos.
This document is an addendum to the PowerPoint to be presented at the Convention. Each of these topics will be addressed in the presentation. These notes give a more complete explanation of:
Threats to the Delicate Ecological Balance
The Galapagos Islands were first discovered in 1836; until that time, the Islands were in a complete ecological balance. The Islands were free of humans and many other predators for most of its history. Today, however, that balance is in danger from the following: Introduced Species As humans began visiting the islands in ships, and today from the native population and tourists, animal species such as: cats, dogs, goats, donkeys, pigs and plant species such as: invasive blackberry and other competitive plants have been introduced that have threatened the delicate ecological balance. One of the most deleterious species is the goat. The goats have decimated tress which formerly provided shade for the tortoises and ground cover for grazing. Because of the lack of shade and grazing, the tortoises use up all their fat reserves, become emaciated, and suffer a premature death. A quote from the Galapagos News, Spring 2006, captures the devastating effect of the goals.
The huge, ancient tortoise –a giant amongst giants - rests unmoving under a scraggly tree that is barely casting enough dappled shade to save it from the killer midday sun. This is a scene from Hell. Where the native Scalesia forest once stood, now only a handful of moribund trees dot a dusty, desert-like scene, each sheltering one or two more tired tortoises. Today a sere wind is blowing and, with roots laid bare in the denuded ground, their remnant skeletons are toppling one by one as I watch. The old tortoise slowly raises his head and sniffs the air with a pumping action of his throat, moist eyes scanning the desolate landscape before resuming his resigned siesta, chin on the ground. The skin around his neck is wrinkled and furrowed like a crumpled newspaper, his fat reserves long spent, his armoured body deeply emaciated. He is waiting for deliverance, having endured in patient reptilian fashion the rampant goat invasion which has laid waste to his volcanic homeland over the past 20 years.
Growing Native Population
The native population on the three inhabited islands will double every ten years. Native Ecuadorians are moving to the Islands for the promise of lucrative opportunities on the land and in the sea.
Longline Fishing
Fishing is one of the few jobs available to native Ecuadorians in the Galapagos. The number of fisherman has increased 100% since 1998. Longline fishing captures an unacceptable number of shards, turtles, and other protected species. The loss of one species can upset the balance of underwater eco systems.
Growing Number of Tourists
The growing number of tourists, although highly controlled by the Ecuadorian government, increasingly brings the threats of introduced species and destroyed habitats.
Climate Change
A passage from Irreplaceable Islands: A Vision for the Future of the Galapagos states: Complicating the islands' problems with introduced species, overexploitation, and habitat loss is the threat of climate change. Warming global temperatures could have widespread effects on the world's climate, and they seem to already be affecting weather patterns in the Galapagos. EI Nino events-which occur when currents shift in the Pacific Ocean and result in warmer waters around the west coast of South America, including the Galapagos-have been known to occur for thousands of years. The warmer waters fuel strong storms in the area and can result in high levels of precipitation. More recently, however, EI Nino events seem to be occurring with increasing frequency and magnitude, and many scientists attribute these changes to the increasing global temperature. EI Nino events tend to have disruptive effects on the biodiversity of the islands, with species such as marine iguanas, penguins, cormorants, sea lions, and fur seals all declining in number during an event. Evidence also shows that the severity of these population declines is related to the severity of the EI Nino event, suggesting that as the events become stronger, population declines could become more severe. If the events are too intense or too frequent, some species, especially those already reduced due to other human-caused pressures, may not have enough time to recover from previous declines and could be pushed to dangerously low levels. The effects of EI Nino events are not just limited to a few species. Many of the species most affected by EI Nino, such as sea lions and fur seals, play important roles at the top of the Galapagos marine food chain, and declines in these populations could mean widespread changes in the marine ecosystem. In addition, the wet weather these events produce could change some plant communities and could favor the introduction of new invasive species that are often limited by the islands' otherwise dry conditions. As managers try to tackle the variety of threats that endanger these pristine islands, the threat of climate change poses unique challenges that complicate conservation efforts.
Protection and Hope
The Galapagos Islands are protected by a number of organizations. In the 1950’s UNESCO brought a group of scientists and conservationists from around the word to take on the challenges of preservation. That first mission brought forth the Charles Darwin Foundation of the Galapagos Islands and the Galapagos National Park Service. These groups were instrumental in the passage of the Special Law for Galapagos that ensured the implementation of an effective participatory decision making process.
Hope
This law also guaranteed the successful completion of the largest island restoration initiative ever attempted in a protected area. Project Isabela eliminated pigs, goats and donkeys from several Islands. Since the eradication process there has been a rapid regrowth of many native plans and a variety of bird species, including petrels and rails, have rebounded, and young tortoises have been spotted ambling among the new vegetation.
All recreational and port fishing in the Galapagos Marine Reserve has been suspended until proper regulation are established and effective enforcement and monitoring of the Reserve are available.
The Birth of the Islands The Islands are all volcanic and have been formed over eons. The following from Irreplaceable Islands: A Vision for the Future of the Galapagos explains the movement of the plates and a hot spot that led to the creation of the Islands. Like all oceanic archipelagos, or groups of islands, the 13 large islands and more than 100 smaller islands, islets, and rocks that make up the Galapagos Islands have been formed by underwater volcanoes. The first of the islands was formed millions of years ago as the Nazca Plate, one of the many tectonic plates that move upon the surface of the Earth, passed over magma "hotspot" in the Pacific. The hotspot formed an underwater volcano that grew tall enough to break through the surface of the water, creating a volcanic island hundreds of miles from the nearest mainland. As the island was formed, the plate beneath it edged eastward, allowing the hotspot to create a new island in its place. Over time, the process has resulted in a cluster of islands all born of the same hotspot. While the plate movements are complex, in general the islands to the west are younger and those to the east are older. The oldest of the existing islands appears to be about five million years old, while the youngest of the large islands, Fernandina and Isabela, are less than one million years old. Fernandina, in fact, could have been formed as recently as 600,000 years ago.
Darwin and Adaptive Radiation
Darwin visited the Islands for five weeks in 1835, traveling on the Beagle. He visited several of the Islands. He wrote of his discoveries in The Voyage of the Beagle.
Darwin’s finches- a species which are found on the Galapagos-provide striking evidence for Charles Darwin's theory of evolution by natural selection and are some of the most well-known inhabitants of the Galapagos. Long-term scientific research during the twentieth century supports the theory that a single species of finch arrived in the islands and began to most likely exploit what food sources it could find. As the birds dispersed to different islands, they encountered different food sources. Those individuals with beak shapes that helped them best take advantage of the available food were to reproduce and pass on their traits. Since birds on different islands were relatives' isolated from one another, they continued this process of evolution independently; eventually becoming so different from birds on other islands that they developed into different species. Scientists think this process-called adaptive radiation -has played out many times in the islands and is responsible for the development of a wide diversity of Galapagos species. (Irreplaceable Islands: A Vision for the Future of the Galapagos)
Consult the following link for a good graphic of the different beak shapes. http://encarta.msn.com/media_461517965/Galápagos_Finches.html
Consult the following link for a more detailed explanation of the relation of the Galapagos discoveries to the full theory of evolution.
http://bioweb.cs.earlham.edu/9-12/evolution/HTML/theory.html
Teaching Resources
There are many teaching resources on line. Type in Galapagos lessons and unit plans and a number of sites will appear. Some of the ones I discovered are:
http://lanic.utexas.edu/project/etext/llilas/outreach/fulbright05/Campe_MagicalPlace.pdf
http://www.nsta.org/publications/interactive/galapagos/
http://www.imax.com/imaxresourceguides/Galapagos.pdf
http://www.galapagos.org/schools.html
Books If you go on the Web, there are a great number of books on the Galapagos. My favorite, that is student friendly and very easy to read is,
The Galapagos Islands: The Essential Handbook for Exploring, Enjoying and Understanding Darwin's Enchanted Islands (Paperback)
by
Marylee Stephenson (Author) "For nearly a century and a
half, since Darwin's visit in 1835, the Galapagos Islands have been recognized
as a living laboratory for the study..." (more)
The Mountaineers Books, Seattle, Washington, 2005 Contact Information
The best site to use to get up to date information on the Islands is to visit the site for The Galapagos Conservancy. This is the oversight group for the preservation of the Islands.
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