Exploring Our Local Waters

Engage

30 Minutes

Ask students to think about the local area and name any water bodies nearby. This might be a river, creek, pond, bay, etc.

Ask how the different aquatic areas are connected to the ocean. Hopefully, students will have a basic understanding of watersheds and be able to articulate how all the areas are linked to the ocean. If students need more background on watersheds, see Rivers to the Sea and Back Again.

Allow students to share experiences they have had on excursions or explorations to the local aquatic areas. Ask them if they discovered anything new during any of these experiences. Remind students that scientists often discover things they didn’t know when they are exploring. Tell them that they are going to explore a local aquatic area, and they will do some activities that are similar to what scientists do when they study the water.

Read the following field trip description and activities. The sampling section may need to be modified, depending on your study site. For example, if a stream is your study site, students may need to turn over rocks to look for organisms. Perhaps a wetlands area near a stream might make a better study area. If the following field trip activity does not fit with your locale and/or student interests and abilities, there are many field trip options listed in the Teacher Background section.

Explain the following sampling methods to students:

Random Plot Sampling:

Systematic Sampling:

Brainstorm what students may find on the field trip. Talk about ideas, questions, predictions of what lives there. Discuss what creatures may be a part of this ecosystem, and make a list of potential living creatures to count and on which to collect data.

Students will record their findings in their science notebooks or on a special data recording sheet. The date, time, weather, and location should always be noted. If students are working in teams of two, one student may be the recorder and the other may be the counter.

If the quadrat falls on a plant or animal, the organism should be included in the survey if it is more than halfway inside the square.

If students cannot identify something, tell them to draw a picture of it or write a detailed description.

Explore

60-120 Minutes

Before you leave the school for the study site, group students in pairs, and assign them a sampling method. Ask them to create a data table in their science notebooks (or provide one that can be glued in later).
You might assign one pair of students to be the reporters. They can photograph or draw the study area, and interview the “explorers” at work. Another pair of students can draw a map of the site, showing prominent biological, geographical, and geologic features, along with any man-made features.

Allow students time to freely explore the field site for the first half hour after they arrive. Encourage them to “discover” at least two things that they had not seen or noticed before.

When their free exploration time is up, gather students together and review the sampling methods and data recording procedures: When recording data, use tally marks in groups of five, then total when finished. For large groups of organisms, count ten and then use that benchmark to estimate the rest. If you are not sure of the identity of an organism, don’t record it. If you encounter a dead or stranded animal, make a note of its location and leave it be. Tell students they should make as accurate a count as possible of each species within the quadrat. If there are too many to count, they can estimate by counting the number within one square inch, then multiplying by the number of square inches in the plot. Give each group a plastic garbage bag to collect any litter they may encounter.

If grasses, algae, or other plants are not too dense, they can be counted individually. Otherwise, have students measure the surface area, in inches, that each species occupies.

When all teams have completed their task, bring the groups together for a summary session. Have each pair tell briefly of its findings. Try to look at the study site as a whole. What are its general characteristics? Was there anything that was surprising? Allow students to share the two new things that they “discovered.”

Explain

50 Minutes

Back in the classroom, have each team record its findings on the data summary sheet .
They can also enter the data into an Excel spreadsheet and create bar graphs of their results, so that they can see graphically how populations of animals and plants at the study site vary.

As students analyze and summarize their data, ask them:

• What species are most abundant?
• What species are most widely distributed?
• What species are present but represented by only a few individuals?
• Did you observe that organisms were only found in specific areas of the site (i.e. different tidal zones)?

Additional questions to discuss:

• Are there any visible changes to the area?
• Are there obvious human impacts occurring in study area?

You may ask each group to present an oral summary of their results, and then lead a discussion of the sampling strategies used. Did one seem to provide better information?

Save your results and share with any local agencies and organizations that might be interested. Emphasize to students that their data will be kept and compared with additional data taken the following year (or previous, if it exists) at the same time. Or if it is feasible, repeat the above sampling scheme in the fall, winter, and spring, to measure seasonal change in the study areas. But most important is the fact that in some remote areas of Alaska, your surveys may be the only ones that have ever been made. Your reports might be of assistance to scientists.

Elaborate

10 Minutes

Ask students what they know about the area that they didn’t know before. How was this activity similar to those done by the researchers we have learned about during this unit? (By this same type of careful observation and record keeping, new discoveries are often made! They make repeated visits to an area, and repeat activities and procedures, then compare results to note changes, etc.).

Are there specific technologies that they have learned about that would have made their sampling tasks easier?
Why might community members be interested in learning about our data?

Evaluate

15 Minutes

Check science notebooks to assess the students’ participation and understanding.

Extend

If you have a local Alaska Sea Grant Marine Advisory Agent in your community, or know of a researcher, scientist, or biologist, ask them to come in to speak with the students about exploration, research, sampling, etc.

Curricular Connections

Art. When counts are completed, each student could use a hand lens to draw a close-up of one organism in the ecosystem.

Math. To compute the average number of animals or plants per plot, divide the total number recorded by the number of plots sampled.