What's Killing the Blue Crab?

Engagement

Objectives

Students will be able to graph data collected from scientific research in order to determine how the crab population has declined and how environmental factors influence Hematodinium outbreaks.

Lesson Materials

1. Anticipation Guide      
2. Data for the graphs       
3. Graph paper or Computer with MS Excel

Procedures

1. Students will complete the anticipation guide on the MD Blue Crab and Hematodinium individually by reading each statement and writing true or false in the "before" column.
2. The teacher will hold a discussion with the class to determine the validity of each statement. The teacher can use a "thumbs-up, thumbs-down" method for quick student feedback. All statements on the anticipation guide are true.
3. Students will be given 1 of 4 sets of data: (1 & 2) date, prevalence, water temperature, and water salinity, (3) year, prevalence, average temperature, and total precipitation, (4) year, crab harvests. The data was compiled from a series of published research articles.
4. Display all graphs for students to see.
5. Discuss with students the relationship between water temperature and Hematodinium, salinity and Hematodinium, salinity and total precipitation, average temperature and water temperature, and finally crab harvests and all environmental factors.
6. Students will develop a hypothesis to answer the question "What is killing the MD Blue Crab?"

References

http://www.jhuapl.edu/weather/education/ACONdata.html

Diseases of Aquatic Organisms.pdf

Gretchen A. Messick, Jeffrey D. Shields. Epizootiology of the parasitic dinoflagellate Hematodinium sp. In the American blue crab Callinectes sapidus. Diseases of Aquatic organisms dis aquat org. vol 43; 139-152, November 14 2000.