courtney emery
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RiparianRiparian Zone Retreat Zone Retreatand population studiesand population studies
Courtney Emery,Courtney Emery,
Honors Biology II,Honors Biology II,
Period 1.Period 1.
Niche of the Striped Skunk(Mephitis Mephitis)
Habitat• Open areas such as woods, grasslands, and
agricultural clearings• Usually within two miles of a water source• Often found in suburban areas
– Buildings provide cover
Food Habits• Omnivore • Mammas, fish, carrion, insects, terrestrial non-
insect arthropods, terestrial worms, aquatic crusaceans
• Leaves, seeds, grains, nuts, fruit
Hunting• Striped skunks are nocturnal and therefore hunt
during the night.• Insects consist of 70% of skunks’ appetites.• Skunks attack bee hives and other nests of
colonial insects.
Factors which Affect Birth Rate of Assigned Animal
• Mating takes place from mid-February to mid-March.
• Skunks usually reproduce once, unless the first pregnancy is unsuccessful.
• The gestation period is from 60-77 days, with delayed implantation probably involved.
• 1-10 offspring are normally produced.
• Skunks are born blind and deaf. They nurse for about a month and a half in the mother’s den. Skunks break from the family about one year after reaching adult size.
• Striped skunks, both male and female, are sexually mature at around 10 months.
Factors Which Affect the Death Rate of Assigned Animal
• Mephitis mephitis has “perhaps the most widely known defense system of any mammal,” the scent-spraying mechanism. Skunks do not use this mechanism unless they feel threatened. They warn before spraying by arching the back and erecting the tail. If, after warning, the skunk still feels threatened, he or she will form into a U-shape and emit two streams of fluid from the scent glands, which are located inside the anus. The fluid causes nausea, eye damage and fatigue, and an offensive odor.
• Most skunks do not live to be older than 3 years.• Many, but not all skunks are affected by the rabies virus. The virus
alters behavior and health of the animal and leads to death.• Over-population of skunks may cause a notable decrease in insects, since
insects are the main source of nutrition for skunks. Predators of the skunk would temporarily increase. Skunks would eventually die off due to the lack of insects and predators of the skunk would therefore die off as well.
Food Chain of the Striped Skunk
Producer
Autotroph
Primary Consumer
Omnivore
Secondary Consumer
Carnivore
Tertiary Consumer
Omnivore
Food web of the Striped Skunk
Herbivore
Producer Omnivore
CarnivoreCarnivore
Producer
CarnivoreHerbivoreHerbivore
Omnivore
Producer
Population Sampling Techniques
• One method uses only a small number of organisms. You can take a small sample of a population and determine from that sample what the entire population might be.
• Another technique is to mark and recapture organisms. Capture the organisms and mark them. Return the organisms to their environment and repeat this process.
Stream Quality Data & AnalysisStream Quality Data & Analysis
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No. oforganisms
Class IClass IIClass III
• As shown in the graph, the stream is very healthy. A large number of Class I organisms indicates a healthy stream.
• Since Class I organisms are usually pollution-intolerant, it is good that there is a large number of these organisms in the stream.
• Describe how the above stream conditions affects your researched organism.
• Describe how your researched organism (directly or indirectly) and the ecosystem would be affected if the majority of the organisms found were in class III.
Water Testing Data & AnalysisWater Testing Data & Analysis
• Describe what the different levels mean pertaining to the health of the ecosystem.
• Describe the ideal range for each factor measured at Powdermill and the possible ramifications for levels outside the ideal range.
• Describe how you organism would survive (using both direct and indirect evidence) if its habitat is close to the stream versus the marsh, and mine waters.
• Do not forget to include how temperature and turbidity affects the ecosystem.
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Nitrate
Oxygen
pH Phosphates
StreamMarshMine
Soil Testing & AnalysisSoil Testing & Analysis
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pH Potash
Phosphorus
Nitrogen
Riparian
School Site
• Describe the importance of pH, potash, phosphorus, & nitrogen levels in the soil.
• Describe ideal ranges of the above chemicals in the soil.
• Describe how chemical levels which are out of their ideal range can damage the ecosystem.
Positive and Negative Factors• Describe how the current stream, marsh & mine waters would affect your organism.
•Describe how soil conditions at the riparian zone would affect your assigned organism.
• Describe factors that positively and negatively affect the riparian ecosystem. You should include common sources of pollution of PA streams and stress how to conserve and preserve the riparian habitat. Include in the description how these factors might affect the assigned organism.
Conclusion
• Describe something new you learned about the ecosystem.
• Describe what you found interesting
• List an environmental topic you might want to research further.
Works Cited
•Included at least three cited sources•Two sources cannot be websites!
Wilke, C. 2001. "Mephitis mephitis" (On-line), Animal Diversity Web. Accessed April 13, 2010 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Mephitis_mephitis.html.