Download Salamander Survey at St. Edward State Park | ESRM 304 and more Study notes Environmental Science in PDF only on Docsity! Environmental Science and Resource Management ESRM 304, Autumn 2008 S. D. West Salamander Survey at St. Edward State Park To familiarize you with a time-constrained methodology (an example of catch per unit effort (CPUE) sampling) and augment the Park database, we will conduct a time-constrained survey to compare abundance levels between coniferous forest and nearby deciduous forest habitats. We will divide into teams of three persons and conduct four 10-min surveys per team. Teams will survey each habitat twice. Areas surveyed will be at least 50m apart. Animals will be captured and placed in plastic bags until identified to species by the class, after which time they should be released at the point of capture. Combining the data between field days this will result in a total of about 60 surveys with 30 surveys in each habitat type. We will pool our capture data (available electronically after Wednesday’s trip) with that from 2004-2007 and each team will prepare a brief report of the results. The report will consist of a short introduction giving the purpose of the exercise, a methods section describing the field and analytical techniques, a results section, and a discussion of the results. Your team report is due at the start of lab next week, and should address the following: 1. Identify the questions posed by the group, e.g., possible differences in amphibian relative abundance or species richness (the number of species) between forest types. 2. Identify the hypotheses under test (the null hypotheses). These could be species x habitat tests or community measures x habitat tests, such as species richness. 3. Describe the nature of the data and how the data were collected. 4. Perform statistical tests of the hypotheses (t-test at α=0.1 will be OK). a. Counts are not normally distributed, so transform the counts with a logarithmic transformation [trans X = log(x+1) or loge(x+1)]. The transformed data (trans X) are used in the t-test. Richness need not be transformed. b. You may have to manipulate the combined data set in Excel before running a particular t-test. c. Use the option of unequal variances for your t-test. 5. Discuss the results of the test and your conclusions relative to a. amphibian species or community measures (richness) in these two habitat types, b. any complications of data interpretation, and c. suggestions for improving future work. Species encountered at St. Edward State Park may include the following: Salamanders Frogs and Toads Northwestern salamander, Ambystoma gracile Western toad, Bufo boreas Coastal giant salamander, Dicamptodon tenebrosus Pacific Treefrog, Hyla regilla Long-toed salamander, Ambystoma macrodactylum Red-legged frog, Rana aurora Rough-skinned newt, Taricha granulosa Redback salamander, Plethodon vehiculum Ensatina, Ensatina eschscholtzii
