Lab 1: Survey Techniques to Census Elephants
2 tablespoons of lentils or split peas (dried)
A calculator
A ruler (with metric units of measure)
Access to the following website:
https://www.biointeractive.org/classroom-resources/great-elephant-census
Ability to print out the document at this website:
https://www.biointeractive.org/sites/default/files/Elephant-Census-Activity-Lands
cape.pdf (If a printer is not available, draw a similar document on a sheet of paper.)
Lab 2: Estimating Stream Diversity
Access to the following websites:
http://virtualbiologylab.org/NetWebHTML_FilesJan2016/StreamDiversityModel.html
http://www.countrysideinfo.co.uk/simpsons.htm
Pre-Lab Questions
What is a “sample count,” and why might we need to use it to estimate elephant populations?
From the perspective of preserving biodiversity, why is a “sample count” important for a species?
What is species richness, and how does it compare to species abundance?
Why does measuring biodiversity matter?
Instructions
Lab 1: Survey Techniques to Census Elephants
Watch this video: https://www.biointeractive.org/classroom-resources/great-elephant-census
Based on the information in the video, complete the table below by typing out the advantages and disadvantages you hear mentioned in the video for each of the different survey methods. You should also add any advantages and disadvantages you think of yourself.
Survey Method
Advantage
Disadvantage
Sample Count
Total Count
Obtain your measurements for the landscape (prior to completing this part of the activity, you will need to print the document at https://www.biointeractive.org/sites/default/files/Elephant-Census-Activity-Lands
cape.pdf):
Each transect has two counting strips (one on each side of the plane’s flight path, represented by a dashed line).
Measure the length of a counting strip in transect A (the counting strip refers to the paler colored areas to the left and right of the dotted line for the transect). Record the value in the “Length (cm)” column below.
Measure the width of a counting strip in transect A. Now, multiply by 2 (multiplying by two will account for the two counting strips in the transect). Record this value in the “Width (cm)” column below.
Determine the area of transect A by multiplying the length by the width, and record the value in the “Area (cm2)” column below.
Repeat steps a-d above for transect B, and record the values in the table below in the row for transect B.
Determine the total landscape area by measuring the length and width of the entire landscape sheet, and then multiplying the total landscape length by the total landscape width to get the total landscape area. These values should be recorded in the appropriate columns in the table below.
Area Name
Length (cm)
Width (cm)
Area (cm2)
Transect A
Transect B
Total Landscape
Now you are ready to start counting your “elephants” (which will be your lentils). Divide your lentils into four approximately equal groups; do not count, just estimate. The next phase of this lab involves four trials (each group of lentils will be a trial). You will follow steps 6-11 for each trial, starting with Trial 1 (the first time you complete steps 6-11, the results should all go in the table in the row marked Trial 1.
Take one of the groups and cup it in your hands about 10 cm above the landscape sheet and in one motion, pull your hands apart to distribute the lentils. Runaway lentils should be returned to the landscape sheet randomly. Just drop them again.
Conduct a sample count for each transect. Before you start counting, decide exactly how you will count the lentils within the counting strips. For example, will you count those that are only partially in the transect or not? Either way is fine, but just be consistent.
Once you’ve counted the lentils inside of transect A (the two lighter regions for that transect), record the number of lentils in the “Number of elephants in transect” column for the “A” row. Then, record the number of lentils in the “Number of elephants in transect” column for the “B” row.
Calculate the density of lentils for each transect by dividing the number of lentils counted in the transect by the area of the transect (found in the previous table), and record this in the data table below in the “Elephant density in transect” column for transect A in the “A” row and transect B in the “B” row.
Calculate the average density for the transects (add densities for both transects that you calculated in step 9, and divide by two). Record this in the data table below in the “Average density per transect for each trial” column.
Now, do a total count for your landscape. Count all of the lentils on your landscape (the entire sheet). Record this in the table below in the “Total count per trial” column.
Repeat this procedure three more times for trials 2, 3, and 4 (your three remaining groups of lentils) so that you have counted all of your lentil groups.
How similar were the numbers between the transect (sample) counts (found in the “Number of elephants in transect” column) and total counts (found in the “Total count per trial” column) on your landscape?
When counting actual elephants across most of Africa, a total count could be less accurate than a sample count. Why could it be a less accurate method?
In the sample count method, did any issues arise? If so, what did you do to address the issues?
What issues do you think researchers might encounter when conducting a sample count, and how would they address these issues?
Discuss two modifications you could make to this model to better represent an elephant census across Africa.
Lab 2: Estimating Stream Diversity
For this exercise, you will examine the impact of pollution on the diversity of organisms in a virtual stream. You will also calculate some common measures of diversity so that you can compare stream habitats with different levels of pollution. You will use this exercise as the focus of your lab report, so be sure to take clear notes as you go.
Go to this website: http://virtualbiologylab.org/NetWebHTML_FilesJan2016/StreamDiversityModel.html
Scroll down and click on “Model Info”. Read to understand the model you will be using.
Start by creating a baseline measurement:
Set “Sampling Time” to 500;
Set “Pollution” to none;
Run the simulation;
Complete the table below by inputting the number of organisms of each type in the “No Pollution” column.
Now create a moderately polluted stream:
Set sampling time to 500;
Set pollution to moderate;
Run the simulation;
Complete the table below by inputting the number of organisms of each type in the “Moderate Pollution” column.
Now create a severely polluted stream:
Set sampling time to 500;
Set pollution to moderate;
Run the simulation;
Complete the table below by inputting the number of organisms of each type in the “Severe Pollution” column.
Organism
No Pollution
Moderate Pollution
Severe Pollution
Caddisfly
Dragonfly
Mayfly
Crayfish
Stonefly
Sowbug
Rif. Beetle
Worm
W. Penny
Black Fly
Gill Snail
Midge
Dobsonfly
Leech
Cranefly
Lung Snail
Total # Species
Total Catch
Now that you have collected some data, think about how you would compare the impact of pollution on stream diversity. To do this, think about more than just the total catch (or the total number of organisms in your net). While total catch is important, it misses some of the key data. As you might guess, pollution can have different impacts on different species, and so in polluted areas, some species may be more abundant while others become less so. One way to determine this is to calculate what is called species richness, which is the number of different species in a given area. You have already recorded this in the table under “total # species”. Based on your table, what trends do you see in total catch and total number of species?
While species richness is important, it does not include some important information, including a measure of the evenness of each species. For example, a habitat could have 100 individuals and only two species. But, does it have 99 of species A and one of species B, or 50 of each? This is important information and can be calculated using the Simpson’s Diversity Index. Use the website (http://www.countrysideinfo.co.uk/simpsons.htm) to learn how to calculate Simpson’s Index (D), and then do the calculation for your three different environmental conditions. Note: Use the equation to calculate D (not 1-D or 1/D). To be able to compare the three levels of pollution, compile your data in the table below.
No Pollution
Moderate Pollution
Severe Pollution
Total Catch
Species Richness (Total # Species)
Simpson’s Diversity Index
Which condition had the highest total number of individuals (species abundance)? Why do you think this is the case?
Which condition had the highest species richness? Why do you think this is the case?
Which condition had the highest Simpson’s Diversity Index? Why do you think this is the case?
Post-Lab Questions
What is the Simpon’s Diversity Index, and what does it tell you?
How does pollution impact various species living in streams? Is the impact the same for all species?
If you were hired to measure the number of elk in Rocky Mountain National Park, what technique would you use, and why?
