MIT

The following categories summarize the various topics I've researched for Las Iguanas Team Two.  

1. Geology of Fernandina and Isabella:
    Fernandina consists of one large volcano 4500 feet in elevation with an 1100 ft deep caldera.  It is still considered active and has had three recent (geologically brand new) erruptions occuring in 1988, 1991, and 1995.  Fernandina is considered the youngest Galapogan Island.
    Isabella consists of six major volcanos, most of which are still active.  It is a relatively young island and is actually believed to be a product of the convergence of several individual volcanoes.  The six volcanoes are: Ecuador, Wolf, Cerro Azul, Alcedo, Sierra Negra and Darwin.  Ecuador ends the northwestern side and is a uniquely asymmetrical volcano, resembling more of a crescent moon from an arial view.  It is not known what caused this peculiar shape.  As Ecuador is in a fairly windless area, wave action the only possible erosion factor.   A possible explanation would be the collapse of half of the volcano along an inner fault line.  It is the youngest volcano on Isabella and, while there have been no recorded eruptions, fresh lava flows are present.  Wolf, on Isabella's northeast flank, is the tallest volcano in the Galapagos reaching an elevation of 5600 feet.  It also has the largest caldera (the central concavity) which is a 7 km by 5 km ellipse.  Wolf has erupted a recorded 10 times, most recently in 1982.  The mineral composition of its lava is very different from Ecuador, and in fact, resembles compositions more commonly found in mid-ocean ridges.  Darwin is directly south of Wolf, and is most historically recognized for its two littoral cones, Tagus and Beagle, which are rings formed by underwater erruptions.  These two cones are favored coves on Isabella and were once used to harbor whaling ships.  Alcedo is found in the center of the island is distinguished by its own unique lava flow and the presence of rhyolite pumice.  Such a crystal composition often results in eruptions of exploding ash instead of lava flows, but Alcedo is not believed to have erupted for 100,000 years.  It is considered the oldest volcano in the Galapagos and is marked as having some of the gentlest slopes.  Sierra Negra is 4900 ft in elevation and is the largest volcano in the Galapagos.  It is also fairly young, less than 4500 years old.  It has erupted ten times in recorded history, the last time in 1979.  Trace element composition in its lava also differ from its neighbors, Alcedo and Cerro Azul.  Cerro Azul is the southernmost volcano on Isabella and last erupted in 1998.  It is a smaller volcano but is taller than Sierra Negra, reaching an elevation of 5541 ft.  

Works Cited:
 
White, E. M. (n.d.).  Galapagos Geology on the Web. Retrieved on October 1, 2004 from the Cornel University Web site: http://www.geo.cornell.edu/geology/GalapagosWWW/


2. A Very Brief Human History of Isabella:
    In 1893, the two major towns on Isabella, Villamil and Santo Tomas, were founded by Don Antonia Gil.  Santo Thomas, located on Sierra Negra, was established for the mining of sulfer.  Villamil, on the other hand, mined coral which was burned to make lime.  With humans came a vast number of invasive species that soon altered the ecosystem; cattle, goats, ferral cats, black rats, burros and pigs dominated and exterminated Isabella's three mammal species.  During World War Two, a radar station was placed on Isabella's northern edge.  The population on Isabella today remains relatively small (1600), but the numbers are increasing at a higher than average rate (6-8%).

Works Cited:

White, E. M. (n.d.).  Galapagos Geology on the Web. Retrieved on October 1, 2004 from the Cornel University Web site: http://www.geo.cornell.edu/geology/GalapagosWWW/

Bernstien-Smith, R. (1998). A Biodiversity Vision for the Galapagos Islands.  Retrieved September 17, 2004 from Charles Darwin Foundation Web site: http://www.darwinfoundation.org/articles/ft00100201.html.


3. Descriptions of Endemic Reptiles:
    The Giant Tortoise, Geochelone elephantopus, is represented on Isabella in the form of five distinct races, each present in a different volcano caldera. In fact,  the largest population of tortoises in the Galapagos is found in the Caldera of the Alcedo Volcano, home of the race vandenburghi.  The creatures are vegetarians feeding on either low growing grasses and shrubs or on Opuntia cactuses, depending up the variety.  Giant Tortoises are classified into two distinct categories by shell shape; there are domed and saddle backed varieties.  Domed Tortoises are recognized by their tall arching carapaces and are generally recognized as the more social and casual of the two varieties.  Saddle-backs are usually smaller with an open arched carapace towards the head which is believed to help them reach the higher fruits of the Opuntia cactuses.  They are usually more stoiche and agressive.  Fernandina is presently without giant tortoises, the last one being found in 1906 (although tentative turtle droppings were found in 1968).  It is believed that Fernandina once had a separate race, phantastica.  It is not known why this species became extinct; the relatively pristine quality of the Fernandina environment and the lack of human intervention leaves only non-human related possibilities.
    The Galapagos Land Iguana, Conolophus subcristatus, is a vegetarian reptile that feeds primarily on Opuntia cactuses.
    Isabella and Fernandino are homes of the largest variety of the species "Amblyrhynchus cristatus", the Marine Iguana.  The large vegetarian feeds almost exclusively on interdidal macroalgae.  They are excellent swimmers and larger males can dive up to 15 meters in depth.  They are a perfectly adapted species to their lifestyle.  They can stand large temperature fluctuations; their preferred body temperature is around 36 degrees centigrade, but it can drop to 10.  Salt glands above the nostril remove salt by concentrating and sneezing it out, resulting in characteristic white caps on the crown of their heads.    
 
Works Cited:
 
Retrieved on September 17, 2004 from Rochester Institute of Technology Web Site: http://www.rit.edu/-rhrsbi/GalapagosPages.html

4. Aquaculture:
    The Galapagos sea cucumber, Isostichopus Fuscus (colloquially, the pepino), is by far the most fished organism in the Galapogan region, consisting of 71% of the total annual fishing yield.  It is a deposit feeding organism (meaning it subsists off of meiofauna living in sediment) found  in sandy bottom and reef environments ranging from Baja California to Northern Peru. In the Galapagos, the pepino is most common in the waters surrounding Fernandina and Isabella.  A steady increase in demand for the sea cucumber from foreign markets (predominantly Japan, Tawain, and the U.S) coupled with a sharp decline in the population of past resources has lead to a situation in which populations are unsustainable.  Recent predictions using trophic modeling programs "Ecosim" and "Ecopath" estimate a rapid 64% decline in current pepino biomass if overfishing continues.  
    Unfortunately, local fishermen do not care for the simplest solution, simply refraining from over-consumption.  In fact, the economic situation encourages their mindset; the price per pepino has declined; in 1999-2000 one sea cucumber was worth on average a sum equivalent $.90 in U.S. currency while in 2001, the price was $.55.  Considering that many locals are sustenance fishermen, falling prices demands larger yields.  Also, with illegal fishing rampant, stricter regulations and education are probably not solid deterrents.
    One possible solution to both a sustainable population of sea cucumbers and a sustainable fishing industry would be actually growing isostichopus fuscus.  Aquaculture is a very common, practical, and successful method that is used to maintain populations of many crustacean and mollusc species.  While it has not yet been successfully industrialized for the pepino, studies show that the organism is an appropriate candidate.  Several trials conducted in Ecuadorian "nursery systems" show that the organism can be stimulated to breed in captivity and have produced 3.5 cm long juveniles in less than three months.  Market size on average for the Galapagos sea cucumber averages around 22 cm.
    Such a solution can be implemented in a number of different ways; aquaculture can replace active fishing or can replenish fishing areas.  It can also be used to increase populations in protected non-fishing zones where numbers have also been declining, primarily because of illegal fishing.  Conversion to aquaculture in the region is a definite possibility.  Ecuador's once lucrative aquaculturing of shrimp ended in 1999-2000 with a mass infection of stock with white spot disease.  Consequentially, many facilities currently exist that could be easily converted.  Also, aquaculture plants would subsequently create jobs that are sorely needed by Galapagos inhabitants/the Ecuadorian people in general.  Opening plants on the mainland could also reduce current stresses on the Galapagos' human population by promoting a return of many of the Galapagos' washashore immigrants.

Works Cited:
Okey, T. A., Banks, S., Born, A., Bustamante, R., Calvopina, M., Edgar, G. J., Espinoza, E., Farina, J. M, Garske, L. E., Reck, G. K., Salazar, S., Shepherd, S., Tora-Granda, V. and Wallem, P. (2003). A Trophic Model of a Galapagos Subtidal Rocky Reef for Evaluating Fishereies and Conservation Strategies.

Hamel, J-F, Hidalgo, R. Y. and Mercier, A. (2003). Larval Development and Juvenile Growth of the Galapagos Sea Cucumber. SPC Beche-de-mer Information Bulletin #18.


5. Marine Ecosensors/Galapagos Climate:
    The marine ecosystem surrounding Fernandina and Isabella is particularly unique.  The Galapagos islands themselves appear at the crossroads between several large current systems that each contribute to the environment in very important ways.  The Humbolt Current carries cold water from the Antarctic region, bathing the Galapagos, primarily the western Galapagos islands Fernandina and Isabella, in cold water.  This is a primary reason for the Galapagos' unusually low marine temperatures, sometimes less than 20 degrees Centigrade.  Also, the presence of deep ocean currents, called Equatorial undercurrents, coming into contact with the archipeligo results in an upwelling of micro- and macro- nutrients vital to the maintenance of the baseline of the aquatic foodchain.  Two primary dissolved ions vital to the growth of phytoplankton, the bottom of the food chain, are nitrate and iron.  Given it's isolated presence, the Galapagos Islands should be nearly destitute of these vital chemicals.  However, it's locale in respect to deepwater currents provides above average concentrations of both nutrients. 
    An ongoing threat to the ecosystems of the Galapagos center around the prospect of global warming.  The warm, rainy season that hits the Galapagos from January to June is partially caused by a rerouting of currents do to a change in westward trade winds.  Concentrations of dissolved nitrate in certain regions surrounding the Galapagos can drop to as low as .2 ppm. While during the dry or "garua" season, concentrations can peak at around 16 ppm.  During El Nino events, the situation becomes more dire and massive die-offs of marine populations occur.  Such seasonal patterns are only currently being understood, and the necessity for studying annual patterns is very important, as change in lengths of such seasons could result in drastic alterations in the ecosystem structure.  Subsequentially, dissolved ions such as nitrate (the marine ecosystem limiting factor) and dissolved Iron (which facilitates nitrogen fixing), salinity (which is greatly affected by precipitation during the rainy season) and water temperature (which changes an average of 4-5 degrees centigrade under El Nino's influence) should all be measured.  Unfortunately, the use of remote sensing for measuring dissolved ions in marine ecosystems is near impossible; it is simply too difficult, expensive and inaccurate.  However, portable devices for salt water sampling are relatively inexpensive, available and accurate.  Possibly the best method  for monitoring would be to establish a network of tethered buoys that take continuous measurements that utilize the known capabilities of remote sensing; temperature, salinity, dissolved oxygen, etc could all be measured at multiple depths by the presence of sensors placed at various altitudes along the tether.  To remove the complicated issue of underwater communication, the surfaced buoys could be used as transmitters using any number of standard airborne methods.  Data could be collected by local fishermen, in exchange for a monetary compensation, who could easily track the buoys via gps, read and record the data presented by the buoy and use provided on-ship equipment to take other necessary measurements. The honesty of the fishermen could be easily monitored by common sense analysis of data patterns.  If a large enough population of interested fishermen is not available, small scientific research vessels could also be equipped.  Coastal environments are also in threatened situations.  Poor waste management results in chemical eutrification of endangered ecosystems, including Isabella's mangroves.  Also, poor management of diesel fuel results in a continuous level of pollution.  Levels on contaminants as well as nitrogen levels and other chemical proxies should be measured in all inletts and estuaries within range of human interference.  These can be taken by field researchers using available water testing technologies.  In addition to this network, satellite imaging of chlorophyll-a concentrations have been used in the past to monitor biological activity in the Galapogan waters.  This imaging produces vital information on the direct changes of algal populations and should be continued.
    Population studies of any aquatic creature, organisms with commercial histories especially, is best monitored via analysis of annual fishing yields and aquatic sampling by research vessels.  Studies gauge the size, age, reproductive abilities, etc of populations to estimate their relative availability.  These methods are in standard use in many countries and should be easily enforced in the Galapagos.

Works Cited:
Palacios, D. M. (2003) Seasonal Patterns of Sea-Surface Temperature and Ocean Color Around the Galapagos: Regional and Local Influences.  College of Oceanic and Atmospheric Sciences, Oregon State University.

Galapagos Climate and Oceanography (n.d). Retrieved September 17, 2004 from: http://www.geo.cornel.edu/geology/GalapagosWWW/GalapagosClimate.html.

Scandol, J. (2003/2004).  Monitoring for Fishery Management Strategies in 2003/2004.  Retrieved October 14, 2004 from NSW Department of Primary Industries Web site: http://www.fisheries.nsw.gov.au/sci/projects/fs/scandol-fms.htm.

Olsen, L. D. (2003).  Selected Applications of Hydrologic Science and Research in Maryland, Delaware and Washington D.C. 2001-2003.  Retrieved October 17, 2004 from USGS web site: http://md.water.usgs.gov/publications/fs-126-03/html/.


6. Terrestrial Sensoring:
    Unfortunately, the most common method for sampling terrestrial organisms bases itself in the process of tracking, capturing, marking and monitoring.  It remains the cheapest and most feasible method to monitor the various reptiles of Isabella and Fernandino.  For land iguanas, marine iguanas and lava lizards, the most common and least expensive marking method involves clipping and cauterizing specific scales in a pre-established code.  The direct beneifits of this method include its permanence and its simplicity.  Such a method can be easily standardized and conducted in the field using a pocket soldering iron. 
    Tortoises are most commonly marked by filing specific patterns on the edge of the carapace.  While Fernandina does not have a known population of giant tortoises, Isabella has five different races, each living on a specific volcano.  They are the following:  Geochelone elephantopus vicina (Cerro Azul Volcano), guntheri (Sierra Negra Volcano), vandenburghi (Alcedo Volcano), microphyes (Darwin Volcano), and becki (Wolf Volcano).  Each race lives in relatively specific zones and can be easily found and marked without capture.  While each race should be marked individually, they should not be restricted to their specific zones in any way, even for the general argument of protection.  Genetic Flow is a natural process that should not be impeded upon. 
    Avian population monitoring is also very important, especially regarding endemic sea birds such as the Galapagos penguin and the flightless cormorant.  The various species of ocean dependent birds are directly effected by climate changes and are therefor every bit as important to monitor as other aquatic phenomena.  El Nino cycles are known to cause severe damage to endemic species and many often don't breed during these periods.  Population censuses have been implemented by the Charles Darwin Research center since 1995.  In 2000, a study was conducted correlating the declining populations of Galapagos Penguins and Lava Gulls with introduced rats.  A current proposal for microchip banding is underway.  Such an advance would greatly facilitate avian studies, which are becoming more and more crucial as introduced species such as the smooth billed ani increase competition and introduce avian diseases.

Works Cited:

Galapagos Giant Tortoises (n.d.). Retrieved September 17, 2004 from: http://www.rit.edu/-rhrsbi/GalapagosPages/Tortoise.html.

Ornithology Program of the Charles Darwin Research Program (n.d.). Retrieved October 17, 2004 from Charles Darwin Foundation Web Site: http://www.darwinfoundation.org/terrest/birds.html.

Census and Monitoring of Birds (n.d.). Retrieved October 17, 2004 from Charles Darwin Foundation Web Site: http://www.darwinfoundation.org/terrest/census.html.

The Effect of El Nino in Galapogos on Marine Fish and Birds (n.d.).  Retrieved October 17, 2004 from: http://www.biosbcc.net/ocean/marinesci/02ocean/enmarfb.htm.

Sampling Herps (n.d.). Retrieved October 24, 2004 from Florida International University Web Site: http://www.fiu.edu/-acaten01/samher2.html.