Coral Reef Checkup!

For the teacher

• Photographs of coral reef organisms to print and cut out
• Google sheet to input all class data, perform calculations, or analyze graphs

Per team of students

• One measuring tape or transect tape
• Easy-to-make quadrats (aim for 1m x 1m, or grab some hula hoops, instead!)
• Species survey worksheet set

Per student

• Background information, instructions, and discussion questions

Transect Activity

1. You have been divided into two research teams. Each team will survey a different coral reef site in Hawaii, either Scenario 1 or Scenario 2.
    
2. Before you start, as a group discuss your site description and formulate a hypothesis about what you might find.
    
3. As a group, lay out your transect line.
    
4. Within your group, identify a buddy. You will work in pairs to survey a specific group of organisms using quadrats. Obtain a copy of the datasheet for your group of organisms. On the top of the page, record your names, date/time, and location (site) name.
    
5. Place your quadrat at the 2m mark so that the transect tape intersects the middle of your quadrat. Record each species contained within your quadrat by placing a hatch mark in the corresponding row on the data sheet. If you find a species that is not listed on the data sheet, note it in your observations at the bottom of the page.
    
6. When you have finished recording all of the data in your first quadrat, move your quadrat to the 4m mark on the transect. Repeat the exercise and record your results. Continue to repeat this procedure at 2m intervals along the entire transect line (that is, collect data at the 2m mark, 4m mark, etc.). You will have a total of 5 quadrats.

Data Analysis

After counting in all 5 quadrats, add up your tallies. You will enter your data on the laptop and graph your data to visualize your findings.

Discussion

After all buddy pairs have entered and graphed their data, re-assemble as a group. Look at your overall results and discuss your results with your group using the prompts on the following page.

How do scientists monitor coral reefs?
Sampling is the process by which organisms in small areas can be counted, or quantified, to estimate abundance over a larger area. The small areas, or samples, must be representative of the larger area for these estimates to be accurate. Sampling a reef allows us to estimate species richness, or the number of species in a given area. Species richness is one measure of the health of a reef, as healthy reefs generally have more species than degraded reefs. To calculate species richness, scientists count all the different species they find while sampling. Species richness does not tell us anything about the relative abundance of these species, but simply lets us know how many are present.

Transects and quadrats are two tools commonly used when sampling and monitoring coral reefs. A transect line is any line marked at regular intervals, such as a measuring tape, that is easy to use in the field. Quadrats are framed areas, such as squares made from PVC pipes. These tools provide a systematic method for determining species richness

Heathy coral reef ecosystems are typically dominated by reef-building corals and fish. These reefs tend to have high species richness and abundance. On degraded reefs, which are those subject to human disturbances, corals tend to be outcompeted by invasive algae or to be smothered by sedimentation or trash. These reefs tend to have low species richness and abundance.