Ecology Box

9. Hare and Lynx Populations

Once students understand the concept of populations, it is important to introduce the idea of population change. There are many reasons for population change – limited resources, predator-prey cycles, human impact, habitat change – to name but a few. In this activity, students learn to graph population data and then use their graphs to evaluate one of the most famous examples of population change, the predator-prey population cycle of the snowshoe hare and the Canada lynx. The data is taken from the 300 years worth of real data collected by trappers of the Hudson Bay Company. This activity provides students a chance to look at real data and make some hypotheses about what causes population change in the real world. The Going Further section is more extensive than for other lesson plans on this site and refers teachers to many excellent population change activities that can be found in other curriculum guides.

8. Ecosystem Organization - Logistics

45-55 minutes



  1. Copies of blank Ecosystem Organization Pyramid
  2. Overhead copy of the Ecosystem Organization Teacher Pyramid
  3. Colored pencils
  4. Optional: photographs or posters of various biomes (I recommend cutting out magazine photos from National Geographic or Smithsonian Magazines or getting old landscape photography calendars when they go on sale in March or April.)

8. Ecosystem Organization

Ecosystem Pyramid student workEcosystem Pyramid student work The study of ecology has many layers, ranging from the individual organism, to the population, to the ecosystem, to the planet. It is important for students to know the levels within this hierarchy and to recognize which level they are focusing on at any one time. For the purposes of this activity, students will learn about the different levels (organism, population, community, ecosystem, biome, and biosphere) by choosing an organism and the illustrating a pyramid about that organism. The result is a colorful display of organizational pyramids.

7. Habitat Survey - Logistics

For habitat survey:
40-50 minutes at the creek
traveling time varies

For setting up the soil analysis tests in the classroom:
10-15 minutes to set up soil separation and Tullgren funnel tests
10 minutes to identify plants and insects

A day later, analyze the results and have a class discussion:
10 minutes to interpret soil separation and Tullgren funnel tests

7. Habitat Survey


In this activity, students finally get to apply their skills of soil analysis and observation to a 1 meter by 1 meter area of the schoolyard, restoration site, or creek bank. Teams of students get down and dirty exploring the soil, vegetation, and insect life in their microhabitat. Students practice using the soil analysis tools they learned previously and also practice using field guides to identify plants and insects. Upon returning to the classroom, they compare their results with other groups to see the differences and similarities between their microhabitats. This is a superb activity to use before and after a habitat restoration project or simply to track changes in a habitat throughout the year. I used this investigation to introduce the idea of native vs. non-native species and to begin a debate about invasive species. My students really “got it” when they examined our adopted restoration area and discovered that there was a monoculture of invasive, non-native English ivy all across our site. They visited our adopted site 3-4 times throughout the year pulling ivy and planting native plants. When all was said and done, they repeated this investigation in the spring to discover exactly the magnitude of the change they made on the environment – and to find that the native plants recruited a wider variety of insects than they had seen at that site in the fall.

Fighting for Foxes - Logistics

30-45 minutes


Copy of the Fighting for Foxes article (downloadable from the summary page or from Smithsonian Magazine).
Copy of the Reading Questions .

Sub Plan - Fighting for Foxes


In order to help understand the complexity of the issues surrounding protecting endangered species, students read an article about the Channel Island fox published in the Smithsonian magazine in October 2004. They create and use food webs to better understand the reasons for the foxes decline. This is a superb follow up to the Food Webs activity.

Field Trip - Point Reyes


This section will give you information to help you plan a field trip to Point Reyes National Seashore. My classes went to Point Reyes for an overnight camping trip between lessons 7 and 8. The first day, we went to the Bear Valley Visitor Center and did a ranger led program called Monitoring Creek Health. After creek monitoring, we played and hiked at Linmatour beach before retiring to our campsite. The following day, we took a kayaking tour of Tomales Bay. Our kayaking guides taught the students about the wildlife and geology of the area throughout the trip. The happy and exhausted students and teacher then made their way back to school.

6. Food Webs - Getting Ready

Getting Ready
For organism research

  1. Create a list of organisms for your students to research.
  2. If you plan to have students pick an organism out of a hat, create slips of paper for each organism.
  3. Collect published field guides for students to use.
  4. Make copies of the Field Guide pages for each student.
  5. Make 1 copy of a Field Guide page for an overhead.

6. Food Webs

In this 2-3 day activity, students choose an organism and research its life cycle, food chain, and habitat. The student research is assembled in 2 ways. First, the classroom is cleared of tables and chairs while students use their organisms to create a food web stretching the length and width of the classroom. Second, the pages are assembled to create a field guide for your local area or for a field trip into a state or national park nearby. I found this to be an extremely effective way to get students interested and excited about an upcoming field trip. I choose insects, birds, fish, mammals, amphibians, and reptiles commonly sighted at Point Reyes National Seashore for students to research a week before the scheduled field trip. On the field trip itself, students were very excited to spot their animals and the student who did the research would usually come forward to tell his or her classmates all about their organism.