Changing With the Tide
This material was originally created for Starting Point:Introductory Geology
and is replicated here as part of the SERC Pedagogic Service.
This lesson plan is written around a brief role-play in which students learn about and act out the behavior of plants and animals in a salt marsh habitat as the tides change. An unusual feature of salt marshes is the dramatic daily change in stresses and interactions that the organisms face.
- Describe three different aspects or life forms of the salt marsh.
- Compare and contrast the low and high marsh.
- Explain what happens in different areas of the marsh at low and high tide.
- Explain the roles different organisms (or other elements) play in the salt marsh by acting out a salt marsh scene.
Context for Use
The full exercise is estimated to take 1-2 hours, but the role-playing segment, transferred to a university marine biology or oceanography classroom, should take about 15 minutes. It is a good exercise to break up a lecture because it gets students out of their chairs (very important for those after-lunch classes). It might make a good introduction to a field lab involving a salt marsh.
Description and Teaching Materials
The Changing with the Tide (more info) lesson plan on the web contains all of the necessary materials, including some links, except for index cards. The instructor can copy and paste the roles from the lesson plan onto the cards, which will be distributed to the students.
Teaching Notes and Tips
The class is originally intended for elementary-school children, but the perspective and specific topic of the class (short-term stresses in coastal ecosystems) make elements of it valuable additions to college classes. The role-play in particular can give students a visceral understanding of diurnal salt-marsh changes that is in some ways more clear than an abstract discussion from a textbook.
The recommended one (for the students to write a version of this lesson for mangrove swamps) may be useful.
References and Resources
The following are only general readings. For more on salt marsh biology:
- Dr. Joe's notes on Salt Marshes, Mangroves, Wetlands
- A photo-rich online botany text, World Vegetation with a chapter on Coastal Salt Marshes and a chapter on Mangrove Swamps and another about halophytes
- A page on New Hampshire salt marshes
- A bibliography on the ecology of salt marsh plant communities.