Download Plenty of Fish in the Sea?

Earthlabs: Investigating Fisheries – Lab 1
http://serc.carleton.edu/eslabs/fisheries/1.html
Name _________________________
Plenty of Fish in the Sea?
PART A: Watery Wasteland
1: In your own words, summarize the main points of the Watery Wasteland
presentation.
There are a number of factors, many involving human influence, that are damaging
marine ecosystems and diminishing fish populations around the world. The long-term
effects could be devastating since nearly 1/6 of the world's population (approx. 1
billion people) rely on fish as their main source of protein. There appear to be no easy
or quick fixes for the damage that has already been done. However, with a
combination of restoration and conservation practices in place, there is hope for the
future health of the oceans and the sustainability of fisheries.
2: Explain what you think the narrator meant when he said that accumulating
devastation of fish populations in the oceans has a "domino effect" on human
populations.
Humans are connected to the oceans. Since humans rely so heavily on the oceans for
resources, particularly food, all of the factors that harm marine ecosystems and
diminish fish populations indirectly affect humans in a chain reaction of
interconnected events.
PART B: Exploring Biodiversity Maps
1:How does the overall color of the map change over time? What does this imply about
the overall diversity of fish in the sea?
The overall color of the map becomes bluer over time, corresponding to an overall
decrease in species diversity.
2: Can you identify any "hotspots" (areas with larger concentrations of species diversity
than the surrounding ocean)? Do they persist over time?
Hotspots appear as red regions on the map. In the 1960s, hotspots appear off the east
coast of South America, off the northwest coast of Australia, and along the southern
coast of Asia. Although these regions consistently display greater species density than
surrounding areas, they become smaller and less intense (more yellow) over time.
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Earthlabs: Investigating Fisheries – Lab 1
http://serc.carleton.edu/eslabs/fisheries/1.html
PART C: Interpreting Species Density Graphs
1: Why is it important to have species diversity in the oceans?
Biodiversity allows the environment to adapt to changing conditions; provides a
variety of food choices; helps preserve raw materials for medicines, polysaccharides,
feed for livestock and building materials; helps control carbon dioxide levels in the
atmosphere; and is important for continued research and discovery.
2: Why do you think large predatory fish are important for maintaining the balance of
marine ecosystems? Why are they important to the sustainability of the fishing
industry?
Large predatory fish are at the top of the marine food chain. As these species
disappear, food supplies disappear and smaller species become dominant and change
the overall balance and chemistry of an ecosystem. This results in declines in water
quality maintenance and increased risks of harmful algal blooms, oxygen depletion,
and death of other fish species.
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