Oysters form oyster reefs, which have been called the “coral reefs” of temperate oceans. The reefs create habitats for numerous organisms and in fact support an entire ecosystem. And we have them here in New Jersey! So they provide a great topic for lessons about our local ocean.
In the, researchers estimated that 85% of oyster reefs throughout the world have been lost in the last couple centuries (see the What’s Hot in Ocean Sciences article in the Spring 2012 newsletter for a summary of the paper http://coseenow.net/mare/newsletter/spring2012/ or see above for a copy of the paper).
But what does that mean for your students? How can you incorporate some of this research into your classroom? Below I have developed a way to bring up these topics (Introducing these Topics) and then provided a list of multiple oyster and oyster reef lesson plans that you can use with your students (Oyster & Oyster Reef Lesson Plans).
Also, Rutgers University runs a program called Project PORTS (Promoting Oyster Restoration Through Schools) to increase an awareness and understanding of the oyster as a critical species and an important natural resource of the Bay; to promote a basic understanding of important scientific concepts and stewardship values; and to contribute to the revitalization of Delaware Bay oyster populations via a community-based restoration project. For more information visit the Project PORTS website.
Introducing these Topics
Oysters provide a unique opportunity to teach your students both about a native species we have here in New Jersey and an ecosystem engineer. Many students are familiar with “ecosystem engineers,” though they might not know it. Ask your students where Nemo and Dory live. They will most likely tell you on a coral reef. Corals are the ecosystem engineers in tropical seas. They create the structure for all the other organisms to grow upon and create the ecosystem. Oysters do the same thing in temperate estuaries. Juvenile oysters prefer to settle on top of other oysters, so over time large structurally complex oyster reefs (or beds) develop. This structure enables many other organisms to thrive where they would not be able to without the oysters. There are many other interesting facts about oysters that you can share with your students (explore some of the resources below to learn more).
Another interesting thing about oysters is that they have fueled coastal economies for centuries. There are reports of ancient Romans eating oysters. There was even a war fought over oysters! This offers an opportunity to integrate some history and social science into your science discussions about oysters. Use the fact that many people eat oysters, even some of your students or their parents, to drive home the human connection with oysters. We rely upon oysters as a source of food and many people rely on them for their job (whether they are fishermen, fish processors, fish market owners, scientists, etc.) Have your students brainstorm how many different people are involved in the oyster industry. Remind them that oysters are filter feeders, so they clean the water of particulates. That means that all of us that like to go swimming or do other recreational sports in bays also rely on oysters to keep the water clean.
After you have introduced some of the ecology and human connections of oysters, tell your students that you are concerned because the numbers of oysters are going down throughout the world. Ask the students how they would go about making an estimate of how oysters are doing if they were oyster scientists. The big points to help the students reach are: 1) to learn about how the abundance has changed over time they will need data on the current abundance as well as past abundances and 2) to make the estimates standardized or comparable across the world they need to come up with an system for classifying the bays from good to bad. For example, in the Beck et al. (2011) paper they used current abundance data (often from fisheries statistics) and past data from 20-130 years before present day. They also made a classification system as: good (< 50% lost), fair (50 – 89% lost), poor (90 – 99% lost), functionally extinct (meaning they cannot support the ecosystem, > 99% lost).
Have the students brainstorm reasons why the abundance of oysters might be going down. Write down their ideas on a large piece of paper in a left hand column. Help the students think of other reasons besides overfishing (or overharvesting). For example, alterations to shorelines have increased the amount of sediment in the water which chokes the gills, changes in the amount of freshwater that enters an estuary as we use it for agriculture and other human uses changes the salinity of and the amount of oxygen in the water, introductions of non-native species into an estuary outcompete the native species, and new diseases that only effect oysters have developed over the past century that kill most oysters before they can reproduce.
It is important to share with your students that there is a lot of good work going on throughout the world that is helping the abundance of oysters recover to higher numbers. In the right hand column of the chart paper have students brainstorm ways that we could recover oysters (maybe by countering each of their ideas of why the number of oysters have decreased). Examples include: improving protection of oysters, creating fisheries management rules that make sure we fish sustainably, protecting oyster reefs as important habitat for the ecosystem, stopping the introduction of non-native species, working to keep extra sediments out of the waterways, determining ways to improve the water quality in waterways to protect oysters from disease, etc.
The benefit of this exercise is having students come up with the reasons why the numbers have declined and creative solutions that we can do to bring the numbers back. Stress with the students that this is what scientists do, in fact more than half of the Beck et al. (2011) paper was highlighting possible solutions.
• Large chart paper and pens
Oyster & Oyster Reef Lesson Plans
- BUILD YOUR OWN OYSTER REEF – an interactive online program for students to build an oyster reef ecosystem (The Academy of Natural Sciences, http://www.urbanrivers.org/oysterreef/index.html)
- EDUCATION ON THE HALF SHELL – using oysters to teach biological concepts (Louisiana Marine Education Resources, http://www.lamer.lsu.edu/halfshell/index.html)
- JUVENILE OYSTER DISEASE: A GROWING PROBLEM – activity to learn about diseases that are slowing oyster recovery using real data from the University of Maine (BRIDGE, Virginia Sea Grant, Virginia Institute of Marine Science, University of Maine, http://www2.vims.edu/bridge/DATA.cfm?Bridge_Location=archive0103.html)
- LIVING BAY ONLINE CURRICULUM – using integrated science and language arts these lesson plans teach students about the bay, and more specifically: managing the oyster industry, oyster farming, oyster disease, harvesting methods and data, economics, sustainable management and conservation (http://livingclassrooms.org/lbo/curr/curr.html)
- MAN AND MOLLUSC – website with many articles and lesson plans about mollusks (http://www.manandmollusc.net/)
- OYSTER WARS OF THE LOWER CHESAPEAKE BAY – learn the history behind the importance of oysters in the Mid-Atlantic region (The Mariners’ Museum, http://www.marinersmuseum.org/sites/micro/cbhf/oyster/mod001.html)
- RIVERLAB – lesson plans about oyster ecology and water quality (Columbia University, score.dnr.sc.gov/ktmlpro10/files/uploads/riverlab.pdf)
- THE LIVING CHESAPEAKE LESSON PLANS – life history information as well as lesson plans on external and internal anatomy, harvesting hemolymph (blood) and isolating blood cells, and a filter experiment to see filter feeding in action (Maryland Sea Grant, http://mdk12.org/instruction/curriculum/hsa/biology/oysters/oysclass.htm)
- VIRGINIA OYSTER HERITAGE EDUCATION RESOURCES – an oyster quiz and two “build a reef” activities (Virginia Department of Environmental Quality, http://www.deq.state.va.us/coastal/oysters.html)
- VIRGINA’S OYSTER REEF TEACHING EXPERIENCE (VORTEX) – a list of resources and lesson plans about oysters and other bivalves in the Mid-Atlantic (Virginia Institute of Marine Science, http://www.vims.edu/research/units/centerspartners/map/education/resources/vortex.php)