Something Fishy

On Wednesday, June 4, 2003, a private group called the Pew Oceans Commission came out with a report that over-fishing at sea, over-development along the coasts and pollution from farms and cities are "leading to decline of ocean wildlife and the collapse of ocean ecosystems."

The commission's report, based on two years of meetings with people in maritime communities from Hawaii to Maine, urges the American government to initiate new ways of caring for ocean ecosystems. Although the U.S. adopted the Sustainable Fisheries Act in 1996, this hasn't stopped the declines in species or the destruction of habitats.

Specifically, the commission suggests that Congress create a National Ocean Policy Act and an independent agency to oversee the management and policing of our oceans. This would include enforcement of new rules, such as tougher restrictions on commercial fishing gear, fish waste and pollution from lawns, roads and fields. The report also concludes the need for more extensive marine research.

With many ocean species and their habitats in decline, it's important to know more about what we're losing. So for this week's lesson, you're going to do a little fishing, and catch some insights on fish biology and discover what species are out there— in the salty seas and in your grocery store.

A Taste of Ichthyology

Ichthyology is the study of fishes, so let's begin at the Florida Museum of Natural History's Ichthyology site.

Start off by learning About the different groups of fishes. What kinds of fish are classified as Agnatha, Chondrichthyes, and Osteichthyes? How do they differ in mouth, scale and fin characteristics?

Next, learn About the anatomy of fish and sharks. Since the main group of fishes people eat are the bony kind, check out the bony fish basics through these diagrams:

• Body Features of Bony Fishes
• Standard Measurements of Bony Fishes
• Mouth Types of Bony Fishes
• Tooth Types of Bony Fishes
• Tooth Patch Types of Bony Fishes
• Gill Arch and Scale Types of Bony Fishes
• Spine, Rays, and Caudal Fin Types of Bony Fishes

What are some of the variations between the different parts of these fishes? Have you noticed any of those differing characteristics before, whether you've seen a fish in person, in a photo or on-screen? Find a picture of a fish and try naming the different parts of it based on what you've learned, along with any particular variations you notice.

Back on the museum's main education page, discover How Fish and Sharks Swim and learn About Fish Adaptation.

How does a fish's physical characteristic relate to its eating habits, how it moves around or how it relates on the evolutionary tree to another species?

Before leaving Florida, explore the museum's Biological Profiles gallery. Pick a few that interest you, like maybe the tiger shark, walking catfish, bluefin tuna, or the swordfish.

How were the fish you chose originally named? Where in the world are they typically found? Are they widespread among several oceans or in a relatively small geographical area? What kind of habitat do they live in? What are a few of their distinctive features?

The Fish Market

Of course, if consumers didn't want fish and fish products, likely these big drops in species numbers wouldn't be nearly as severe as they are. But the fact is that many people like to eat fish, because they're tasty and healthy sources of protein and important nutrients.

You've probably seen one or more varieties of fish in your local grocery store or on a restaurant menu. So how many pounds of these fish have been caught for market over the years?

Check out the Annual Commercial Landings by Gear Type database provided by the National Oceanic and Atmospheric Administration's Fisheries Statistics and Economics Division. In the page's query form, type in one type of fish people eat, such as tuna, halibut, swordfish or marlin. Then choose 1950 as the Earliest Year and 2001 as the Lastest Year. Choose any geographical area or state you'd like, and either one specific gear type or All Gear Individually. Hit the Submit Query button.

When the table listing is displayed, try going down the list and adding up the pounds of fish harvested for each year. Did the amount harvested go up or down over time? Was one type of gear typically used more often than another?

Perform a similar query for another type of fish. Compare your results, either by just looking at the raw annual numbers or by graphing them. Do you notice any patterns in the amount of fish harvested over time? Did fishermen use one type of gear for one fish and another for the second? If so, why do you think that's the case?

Also, add up the $ amounts by year and compare the dollar values per pound for each year. Did the market value go up or down over time? Was one type of fish consistently more valuable than the other, or did one surpass the other in value over the years?

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