Lab 10 Endangered Species

·     The Desert Tortoise (Gopherus agassizii)

      State the scientific name and common name of your organism, its taxonomic Order, and taxonomic Family.  

      Kingdom: Animalia. Phylum: Chordata. Class: Reptilia. Order: Testudines. Family: Testudinidae. Scientific Name: Gopherus agassizii. Common name: Desert Tortoise.

Include two photos or one video (no more than two minutes in length) illustrating the organism in its natural setting. Do not use any material showing harm to this organism.

Explain this organism’s ecosystem role. Since the desert tortoise is a primary consumer, their pray consists of various mammals, avian (birds), and reptile predators. Desert tortoises are also  called ecosystem engineers because they make us of other animals’ hard work like digging burrows that are used as shelters by snakes (Serpentes), lizards (Sauria), birds (Aves), rodents (Rodentia), javelinas (Pecari tajacu), and insects (Insecta) and other invertebrates. Desert tortoises themselves take advantage of packrat (Neotoma albigula) houses for shelter. In one study, desert tortoises were found sheltering with large colonies of Africanized honeybees (Apis mellifera)--a very effective defense against predators! Finally, desert tortoises have few external parasites, but they are host to intestinal pinworms (Oxyurida).(Crozier).

Describe at least two ecological services this organism provides for humans and other species (at least two ecological services for each, humans and other species). This might involve its food web. 

In the past, desert tortoises were used by indigenous peoples of the American Southwest for food and medicine, and the shells were used to make bowls, ladles, and shovels. Desert tortoises were also central figures in the folklore of the region. Desert tortoises are occasionally still used for food in some parts of Mexico. In addition, many people in Arizona keep desert tortoises as pets, though the keeping of captive tortoises is strictly regulated: tortoises must not be collected from the wild, only one tortoise is allowed per family member.(Crozier).

Include and explain in words, a chart or graph showing population of this organism over time. 

 

State how the equation I = PAT is involved in the threats to this organism.

 

I = PAT stands for (I) Environmental impact = population (P), affluence (A) and technology (T) to environmental impact (Santa Barbara Foundation Family).  As our population grows this animal becomes more prone to threat. Since our actions as one affects our environment, it also impacts every organism on the planet in some way shape or form.  As population increases we build more, which in return results in more roads etc. This is where affluence comes in because we can’t seem to stop building and humans want more and more. We feel as though we must make more roads to get places and to build in places that are necessary. Which bring us into technology, we need the technology to build and develop these new places. For example, in 1995, populations in areas of the Mojave and Colorado deserts with comparatively little human activity were generally stable or declining more slowly than populations in areas with high levels of human activity (Santa Barbara Foundation Family).

Referring to figure 9-3 in your text book, determine and describe the characteristic(s) that endanger(s) your species.  

The Desert Tortoise extinction falls under every part of HIPPCO. Habitat degradation from overgrazing, vehicle use, and invasion by nonnative grasses may have substantial negative impacts on desert tortoises. The impacts of severe grazing on their habitat suggest that high levels of grazing likely have negative impacts on desert tortoises. Potential effects of intense grazing that could negatively impact desert tortoises include soil compaction, decreased cover of annual plants, introduction of nonnative species, competition for forage, and the potential for trampling desert tortoises and their burrows. Invasion of nonnative grasses and the potential for a nonnative grass/fire cycle pose major threats to desert tortoises. The release of captive desert tortoises with upper respiratory disease syndrome, which is typically fatal, into the wild may have resulted in the infection of wild desert tortoises (Santa Barbara Foundation Family). Although a new species is not being introduced, I feel it is an example that could fall into introducing a new species that result in destruction to the species. Climate change may negatively affect the desert tortoise if droughts become more frequent or severe or if precipitation increases and results in the spread of nonnative plant species (Santa Barbara Foundation Family).

Determine if this organism is affected by density dependent and/or density independent factors. Explain the situation in some detail.  

The Desert Tortoise would be considered to be affected by density independent because of the main threat of humans including, but not limited to fire mostly human caused. 

Describe the feedback loops involved.  

A positive feedback group is involved with the Desert Tortoise especially because of the invasive plant life. This plant life is burned it causes a decrease in habitat for the tortoise. Since most of their food comes from plant life this causes a worse and worse situation for the essential habitat of the tortoise.

Describe how global climate change is affecting or is predicted to affect this organism’s habitat. 

Climate, like stated above is having a negative effect on this species because of the plant life. The habitat is in need of native plant species and thus a drought inclines their habitat to inhabit nonnative plant species more frequently. 

Referring to the three principles of sustainability, why should humans care about this organism? 

This species is considered ‘keystone’ to the Mojave – meaning that it plays a significant role in maintaining the integrity of the desert ecosystem and, if lost, will put other species at risk for extinction. (Collaborating for a sustainable future for wildlife). Maintaining our impact on this species by educating the public of this threatened species will in return help us a unit to make changes to help our ecosystem survive. The Desert Tortoise spends about 95% of its time underground in the burrows they make, which act as a protector for other species as well. This acts as a very important role for many species living in the desert (Leon).

Name and give a two or three-sentence description of two individuals (not groups) who are champions of this organism.  

Roy Averill-Murray, Gopherus agassizii expert, is a part of the U.S. Department of Fish and Wildlife Service, of which is working to protect the Gorpherus agassizii (Richards-Dimitrie). Roy is the Desert Tortoise Recovery Coordinator that is from the Nevada office and has been with the U.S. Fish and Wildlife Service since 2004 (Averill-Murray). Christopher R. Tracy is an expert on the desert tortoise (gopherus agassizii), having written an entire manuscript, “Desert Tortoise Recovery Plan Assessment”. He is an assistant professor at California State University, Fullerton, having gotten his masters at the University of Oklahoma, and his PhD at the University of Wisconsin, Madison. His research includes Physiological Ecology of Reptiles and Amphibians, Physiology of Terrestrial Vertebrates, Ecology of Desert Vertebrates (Christopher R. Tracy).

Name and give a two or three-sentence description of two individuals (not groups) who do not want this organism protected, at least not in their “own backyard.”  

Cliven Bundy, who is against preserving the Desert Tortoise. Clive stated that he “will not willingly sell their grazing privileges to create another preserve”(Fuller). Unfortunately, after strenuous research, I was unable to find another specific name associated with another individual against the protection of the Desert Tortoise. Although, there are many ranchers who are also opposed to the idea none were publicized by name. However, it was fought that the government is acting hypocritical in that they will be euthanizing these animals’ dues to budget cuts.

Include a link to one recent scientific article or story about this organism that was written or produced in the last year. Suggestions for sources include ScienceNews, ScienceDaily, and NPR.  Your article or story must include some peer-reviewed material or state the view of scientific experts. Introduce the links in your report by giving a one or two-sentence summary of each.    

An article written in April earlier this year, talks about how the Desert Tortoise will soon be euthanized due to federal funds. The Desert Tortoise Conservation Center near Las Vegas has been in operation for decades and now the funds to run the conservation are dwindling. There has been many laws put into effect to help these critters to stay safe from human destruction. As a result any new tortoises brought to the center will now be euthanized as there are no other options (Animalsoul). <http://ireport.cnn.com/docs/DOC-1119214>

State the Precautionary Principle in your own words. 

The precautionary principal involves taking precautionary measure to prevent species from being extinct. We can become more aware that our actions are affecting extinction of every species even if we are lacking scientific knowledge of this happening for some species.

                              Works Cited

“Collaborating for a sustainable future for wildlife.” C2S2 Conservation Centers for Species Surival. Web. 2014 July 18 <http://conservationcenters.org/species-conservation-priorties/desert-tortoise/>.

“Christopher R. Tracy.” California State University, Fullerton: Biological Sciences. April 7, 2014. Web July 19, 2014. <http://www.fullerton.edu/biology/People/facultypages/tracycr.asp>

Crozier, G. 1999. "Gopherus agassizii" (On-line), Animal Diversity Web. July 19, 2014 <http://animaldiversity.ummz.umich.edu/accounts/Gopherus_agassizii/>.

“Desert tortoise (Gopherus agassizzi).” U.S. Fish & Wildlife Service Species Profile.” 18 July 2014. Web. 18 July 2014. <http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=C04L>.

 

“Gopherus agassizii.” The IUCN Red List of Threatened Species. Web. 16 July 2014. <http://www.iucnredlist.org/details/9400/0>.

Mayer, Rachelle. Gopherus agassizii. 2008. 18 July 2014 <http://www.fs.fed.us/database/feis/animals/reptile/goag/all.html>.

“Mojave Population of the Desert Tortoise (Gorpherus agassizzi).5-Year Review: Summary and Evalutation.” U.S. Fish and Wildlife Service Desert Tortoise Recovery Office Reno, Nevada.” 30 September 2010. Web. 18 July 2014. Pg18 <http://ecos.fws.gov/docs/five_year_review/doc3572.DT%205Year%20Review_FINAL.pdf>.

“The Sustainable Scale Project.” Santa Barbara Foundation Family. 2003. 18 July 18 <http://www.sustainablescale.org/ConceptualFramework/UnderstandingScale/MeasuringScale/TheIPATEquation.aspx>. 

Tuma, Michael. “Agassiz’s Desert Tortoise Gopherus agassizii.” Reptiles of Arizona. 2008. Photograph. Web. 15 July 2014. <http://www.reptilesofaz.org/Turtle-Amphibs-Subpages/h-g-agassizii.html>. 

  

Wildertography. Desert Toroise (Gopherus agassizii) Attacks! 15 April 2012. <https://www.youtube.com/watch?v=Z4hDadw7HVc>.