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to announcements page.Q2: Treat each day and stream reach as an independent sample (i.e., your sample size "n" will simply be the number of sampling units in that particular category). Organize your data into tables or graphs to help you make comparisons. Briefly describe and discuss your results.
Q3: NOTE: There was a typo in the mark-recapture data for giant salamanders in Eldorado Creek. The "Mi" value for 9/13/96 should be 13, not 23 as indicated in the table. The number of marks available should not decrease unless there were deaths and deaths exceeded new captures!
Q5: This should read "compare density estimates...." In other words, calculate a standardized "density" measure (#/m2 or #/linear meter) for tailed frogs (adult and tadpole, separately) in the 2 sampling-unit sizes (5m versus 30m reaches) in each stream. Note: data for some 30-m reaches have been pooled into 60-m samples. Calculate a density measure for the 60-m reaches like you did for the 30-m reaches (i.e., use the same units of measure) and then calculate the mean density of tailed frogs based on both the 30 and 60-m samples (i.e., sum the density over all 30 and 60-m samples and divide by the total number of samples). Compare these means and their SE's to means based on 5-m samples.
Is there any sampling-unit size that is better for sampling tadpoles? adults?
What would you do if you wanted information on both adults and tadpoles? Note: question #1 is closely related to question 5, except you now have some real data upon which to base your conclusion.
Also think about the differences in sampling methodology between the 5-m versus the 30-m reaches. How might this have influenced your results?
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Revised: 25 August 2011