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Snail Fronts and Salt Marsh Die-Offs

Graph from the activity

Topic

  • Ecology
  • Ecosystems
  • Environmental Science
  • Conservation
  • Math & Computational Skills
  • Graph Interpretation

Resource Type

  • Activities
  • Data Points

Level

High School — GeneralHigh School — AP/IBCollege
Saved By
12 Users
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Description

This activity guides the analysis of a published scientific figure from a study that investigated whether periwinkle snails contribute to salt marsh die-offs.

Periwinkle snails graze on Spartina cordgrass, an important salt marsh plant. When cordgrasses are stressed during droughts, snail grazing intensifies, causing them to die off in localized areas, which forms bare patches called mudflats. Over time, snails move to areas with healthier grass, creating a “snail front.” The figure shows the density of periwinkle snails and biomass of cordgrass in a Georgia salt marsh at three time points: at the beginning of the study (top), after 6 months (middle), and after 12 months (bottom). The “Educator Materials” document includes a captioned figure, background information, graph interpretation, and discussion questions. The “Student Handout” includes a captioned figure and background information.

Student Learning Targets

  • Analyze and interpret data from a scientific figure. 
  • Describe how interactions between climatic stressors and trophic interactions can impact an ecosystem.

Estimated Time

Within one 50-minute class period.

Key Terms

biomass, consumer, drought, grazer, line graph, top-down control, trophic interaction, wetland

Primary Literature

Silliman, Brian R., Johan van de Koppel, Mark D. Bertness, Lee E. Stanton, and Irving A. Mendelssohn. “Drought, snails, and large-scale die-off of southern U.S. salt marshes.” Science 310, 5755 (2005): 1803–1806. https://doi.org/10.1126/science.1118229.  

To access this article, set up a free AAAS account.

Terms of Use

Please see the Terms of Use for information on how this resource can be used.

Accessibility Level (WCAG compliance)

PDF files meet criteria.

Version History

Date Published 03.27.17
Date Updated 12.01.21

NGSS (2013)

HS-LS2-2, HS-LS2-6; SEP2, SEP4, SEP5

AP Biology (2019)

ENE-3.D, SYI-1.H; SP1, SP4

IB Biology (2016)

C.1, C.5

AP Environmental Science (2020)

Topic(s): 1.3, 1.9, 1.11, 2.2, 3.5
Learning Objectives & Practices: ERT-1.C, ENG-1.B, ENG-1.D, ERT-2.B, ERT-3.F, SP2, SP5

IB Environmental Systems and Societies (2017)

2.1

Common Core (2010)

ELA.RST.9-12.7
Math.S-ID.3, Math.S-IC.1; MP2, MP5

Vision and Change (2009)

CC5; DP2, DP3

Materials

Resource Google folder (link)
Image (JPG) 151 KB
Student Handout (PDF) 1 MB
Educator Materials (PDF) 1 MB
Image - Español (JPG) 115 KB
Student Handout - Español (PDF) 433 KB
Educator Materials - Español (PDF) 444 KB

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