Glacier Bay Crabs

Sub-concepts:
Life history of Dungeness crabs; distribution of Dungeness crabs throughout Glacier Bay; animal ecology; the effectiveness of a marine preserve for protecting species, such as Dungeness crab; special adaptations to a marine environment

Generalization:
Dungeness crabs are an important benthic species of Glacier Bay. Glacier Bay was closed in 1999 to all commercial fishing of Dungeness crabs because of the possibility of a collapse of Alaska's Dungeness fisheries. Preliminary studies indicate that this closure will increase the size and abundance of this important species, as well as improve its genetic biodiversity.

Guiding Question:
What factors are important to maintaining a strong population of Dungeness crab in Southeast Alaska?

Critical Content
Students will know ...

1. The life history of Dungeness crabs
2. The place of the Dungeness crab in the food web of Glacier Bay's marine environment
3. The physiological adaptations that allow crabs to thrive in the extreme conditions of Glacier Bay
4. The relationship between a thriving fishery and marine preserves

Skill Objectives
Students will be able to ...

1. Compare and contrast the life histories of human beings and Dungeness crabs.
2. Create displays to share information on Dungeness crabs.
3. Build models to compare and contrast members, both terrestrial and marine, of the Arthropoda Phylum.
4. Research and illustrate the place of the Dungeness crab in the food web of its marine environment.
5. Analyze data from a study on the distribution of Dungeness crabs in Glacier Bay to draw conclusions about the animal and its ability to adapt to the extreme conditions of the environment.
6. Examine a brief history of the commercial Dungeness crab fishery in southeast Alaska and its effect on the population of Dungeness crabs.
7. Assess the effectiveness of a marine preserve on the continued health of a commercially important population of animals.