Monitoring Life in the Rocky Intertidal Ecosystem
Grade Level: 9-12
The five national marine sanctuaries along the West Coast monitor the
health of the rocky intertidal ecosystem. One way of doing this is to
collect data on the relative abundance of the organisms living in that
ecosystem. Since this is such a big task, the national marine sanctuaries
are training students in how to follow standardized protocols to help
with the monitoring. The information collected is added to an online database
that the sanctuaries use to collect baseline data and track long-term
changes in the environment. This activity will allow you to learn the
sampling techniques used in the field by these citizen scientists who
participate in LiMPETS.
For a group of three to four:
- Photos of the rocky intertidal zone
- 6 photo quadrats printed on 8.5" x 11" paper
- Photo quadrat data sheets
- Photo quadrat answer sheet
- Animal and algae ID cards
Note: The images and sheets listed above can be downloaded from http://limpets.noaa.gov.
Navigate to "Project Information," then select "Teachers
and Students" from the lefthand navigation bar and select "Teaching
- Look at the photos of the rocky intertidal ecosystem. What are the
characteristics of this environment? Why do you think that monitoring
the abundance of organisms in this ecosystem is important? How could
this information be used? Discuss with your group.
- You will need two photo quadrats and two ID cards. On each photo quadrat,
draw six equal-sized boxes (4" x 4.5").
- You will monitor the abundance of algae and animals in each quadrat
using two methods. For the larger invertebrates, you will record a total
count of the number of individuals on the data sheet (under "individuals").
For algae and the more abundant animals, record the number of squares
out of six with any portion of the algae or animal under "count
and record" on your data sheet. The organism is counted if it is
attached in that square.
- Fill out the photo quadrat sheet by looking to see if each species
listed on the data sheet is present in the quadrat.
- First with your group, and later as a class, discuss which organisms
were hard to identify and how this might be different in the field.
What are some problems you think you might have in using this method
in measuring relative abundance of organisms in the field? Why do you
think it is important to monitor the health of the rocky intertidal
ecosystem? What can this information tell scientists and resource managers?
This activity was adapted from the LiMPETS Rocky Intertidal classroom
kit developed by Dr. John Pearse and Dawn Osborn, University of California