• This extra credit assignment is worth up to 6 assignment points. It can be completed anywhere that you have internet access. When you have completed the assignment, turn your worksheets in at the front desk in the Biology Learning Center. Initial and date the Assignment Check-In Sheet at the front desk when you turn in your assignment. Your instructor will grade them and return them in a few days.
• Extra credit points are added to your total lab points at the end of the semester.
• You can find a grading rubric for this extra credit assignment here.
• You do NOT have to complete this extra credit assignment before you can take the Unit 6 test.
• This extra credit assignment must be turned in before or on the Last Day for Extra Credit Assignments. Please check your syllabus, the Deadlines page, or ask at the front desk for this date.

OBJECTIVES

• Learn about risks to your own health from eating seafood
• Learn about risks to fish populations and marine ecosystems

INTRODUCTION

Choosing what fish to eat may seem like a simple matter of taste. However, recent understanding of human effects on the world’s fisheries have brought both environmental and health issues into the decision. Overfishing is causing a decline, and near extinction, of many popular commercial fish species. Nevertheless, many of these species continue to be fished, and the more consumers demand them the faster they will disappear.

How can you know which species it is safe to eat, from the perspective of biodiversity preservation? One source of guidance is the Monterey Bay (California) Aquarium, whose Seafood Watch Program guides consumers to choose seafood that is:

• Healthy for humans (not polluted with toxins such as mercury) and caught in a way that preserves habitat and eliminates by-catch (animals such as dolphins and sea turtles that are accidentally caught in the net)
• Farmed in a way that cares for the surrounding environment (many fish farms dump thousands of pounds of pollutants into the water daily)
• Manages so that healthy populations are maintained (overfishing is a significant threat and has already brought many species in the brink of extinction)

The Seafood Watch Program groups seafood into three categories. “Best choice” includes those species with healthy sized populations that are being fished in a sustainable fashion. “Caution” includes species that may be sustainable in some locations, but not others; it is important to know which region your choice comes from before deciding to eat it. “Avoid” includes species for which there is no sustainable fishery. Buying and eating these fish will likely endanger the species further.

Unfortunately, the long-term survival of fish species is not the only thing to be concerned about when eating seafood. Recent scientific studies have shown that mercury contamination of seafood is increasing. The highest levels of mercury are found in predatory fish high on the food chain, such as swordfish and albacore tuna; however, it exists in all seafood. Mercury is a particular health concern for children and pregnant women, but it can cause adverse health effects for anyone.

CALCULATING YOUR MERCURY RISK

The Sea Turtle Restoration Project’s website, besides providing information on protection of the endangered sea turtle, provides an online “mercury calculator” that lets you determine the amount of mercury in the seafood you might eat. The website also provides information and links to the U.S. Food and Drug Administration on recommended dietary mercury levels.

So, how much seafood do you eat? Record your answer to Question 1 on your Step 4 worksheets. A smallish portion is probably about 4 ounces, a medium-size portion about 6 ounces, and a large portion about 8 ounces. If you have trouble filling in Table 1 because you do not like to eat seafood, pick a friend or relative that does like to eat seafood and answer the questions from their point of view.

Use the online "mercury calculator" at the Sea Turtle Restoration Project's website to calculate your weekly and monthly mercury consumption. Finish filling out Table 1 and answer Questions 2 and 3.

Now, try to balance protecting your health with protecting commercially overfished species. From the Monterey Bay Aquarium website or from the Desert Museum's website, pick some of the “Best Choice” species and answer Question 4.

To answer the questions 4–7, you will need to go back to the "mercury calculator" and see which of the Best Choice types of seafood have high and low mercury levels.

If you have trouble answering Question 7 because you do not like to eat seafood, pick a friend or relative that does like to eat seafood and answer the questions from that person's point of view.

Some Additional Information about Purchasing Seafood

It's often difficult to tell in the grocery store anything about the seafood that is sold there. Where did it come from? Is it safe to eat? Here are a few "factoids" that might help you out.

• Country-of-origin labeling tells shoppers where seafood came from and whether it was farm raised or wild caught. When COOL was established by federal legislation, it was supposed to apply to meat and produce, too, but under industry pressure, Congress has delayed additional implementation until 2008. See http://www.ams.usda.gov/cool
• USDA organic standards do not exist for seafood. If fish is labeled "organic," it is likely been certified by an agency in another country. California outlawed such labeling for seafood in January, 2006.
• FishWise labels use color coding to indicate whether a specific fish (not just the species) is a good (green), questionable (yellow), or bad (red) environmental choice. The labels, developed with Environmental Defense, also say where the fish came from and how it was caught. See http://sustainablefishery.org
• Marine Stewardship Council certification was orginally established by World Wildlife Fund, which still plays an advisory role. It appears on wild fish from well-managed and sustainable fisheries. See http://www.msc.org
• The Seafood Safe label indicates the number of monthly servings women of child-bearing age can safely eat, based on mercury and PCB levels. So far, only the Ecofish brand carries the label, which also is associated with Environmental Defense's oceans campaign. See http://seafoodsafe.com

This information on shopping for seafood was adapted from Hattam, Jennifer, 2006, Truth in labeling. Sierra, November/December 2006, p. 53.

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