Caption: A female rusty crayfish with partially developed eggs attached to her abdomen. Gretchen Hansen, a zoology graduate student at University of Wisconsin-Madison, is monitoring the invasive rusty crayfish in Sparkling Lake, Wis., where trapping and native, carnivorous fish have caused a dramatic population decline, helping to restore natural conditions to the lake.
Photo: Gretchen Hansen
Date: 2009
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Caption: University of Wisconsin-Madison undergraduate students Gretchen Hansen and Laura Conner deploy a crayfish trap in Sparkling Lake, Wis., as a part of an intensive removal project for invasive rusty crayfish. Hansen, now a graduate student in zoology at UW-Madison, continues to track the ecological impact of invasive crayfish in Sparkling Lake.
Photo: Catherine Hein
Date: 2003
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Caption: A male rusty crayfish, or Orconectes rusticus, found in Sparking Lake in northern Wisconsin. Rusty crayfish are an invasive species now found in lakes and streams across the United States. Photo: Brian Roth
Date: 2004
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