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Dive Dry with Dr. Bill

#300: Our Meals... and Fish Meal

This is the 300th column in my series... and some of you are still wide awake! For others it has been an excellent cure for insomnia. Let's see if you can make it through this one without getting too drowsy. If you do, try reading my 719 page doctoral dissertation and you'll never have trouble sleeping! Just ask my professors.

Although mating is one of my top two favorite subjects, today I'm going to focus on the other favorite subject... which I do far more of than the former! That's right, munching. I am a red-blooded American, flesh eating carnivore. When it comes to munching, I love nothing more than a big flank steak barbecued on the grill. My other favorite, filet mignon. Of course I even eat the flesh of my fishie friends, preferably salmon but I won't turn down halibut, swordfish or white sea bass.

Some of my diving buddies ask how I can eat our friends, thus affecting the marine ecosystems we love. The answer is easy... survival! I am one who believes in the mutual eating society... as long as I'm not just below the top rung on the food chain! Some are vegetarians and wonder how I can eat meat, fish or poultry (since I love turkey). A few of these vegetarians take a "holier than thou" attitude which, as you shall see, is largely unwarranted.

We all impact the marine environment whether we live along the coast or are imprisoned inland in largely land-locked locations like Las Vegas, Chicago or Paducah (KY)... or are strict vegetarians, prefer a more California style cuisine or are Midwestern meat and potato eaters. Since I've included vegetarians in that group, I'm not simply referring to those of us who eat marine critters like crabs, lobster or shrimp. Perhaps the only folks who can claim a high moral road here are those that grow their own food organically. Let's look at my reasons.

Agricultural plant crops even from places far from the ocean like the American Midwest are grown with artificial fertilizers and man-made pesticides. The manufacture of these products often involves impacts on the oceans whether directly or indirectly. Their application on farmlands often involves runoff during rains. That runoff eventually finds its way to the ocean where the pesticides and fertilizers can cause great harm. When I dove Australia's Great Barrier Reef in 2001, it was experiencing decline due to agricultural runoff there. Fertilizers caused algal blooms which impacted the coral reefs, preventing coral polyps from feeding by smothering them. Currently scientists are concerned about the large areas known as "dead zones" along the coasts of many nations where such artificial enhancement of nutrients has caused bottom depths to become largely devoid of oxygen, and therefore life... except bacteria.

But, you say, I avoid all fish and just eat poultry, pigs or beef. How can I be affecting the marine environment? Back in the days when many of my German relatives were farmers, raising such critters both in their homeland and in the Midwest, things were different. Cattle grazed on grass, chickens ate grains and pigs... well, they ate almost anything including my table scraps. And we humans ate them rather than processed foods. I can remember my relatives wringing the necks of the chickens we would eat for Sunday supper when we visited their farm.

Now many of these same animals are raised in high concentrations on factory farms rather than dispersed on numerous scattered family farms. By raising so many critters in one area, the wastes are concentrated and can lead to serious pollution of rivers and eventually the sea during periods of heavy rain and flooding. These issues can be addressed to a degree by better non-point source pollution control methods. However there are important issues you may not be aware of that directly affect the health of our marine ecosystems.

How many of my readers were aware that many of the chickens, pigs and cattle that find their way to our grocer's shelves had their last meal of... fish! That's right, each year some 14 million tons of fish; mostly anchovies, sardines, mackerel and herring; are fed to farm animals world-wide. That is close to 20% of all the wild fish caught globally! For comparison, that is six times the amount of seafood that Americans consume each year. Westerners often criticize Asians, especially the Japanese, for their global fisheries harvest. However, pigs and chickens eat twice the amount each year that they consume.

Why should we reconsider this practice? Of course there are several reasons. First, we are taking food stocks in the form of baitfish from our marine ecosystems. Left in place, these baitfish would benefit the entire ecosystem, supporting far more species further up their food chains. That would leave more fish to feed white sea bass, billfish and other predators. An ecosystem has a certain limit to how many of a species it can support. This "carrying capacity" is determined by the availability of resources like food. Fewer munchies, fewer fish. Of course I could use a few fewer munchies myself!

"Fuel" efficiency is a popular topic these days given the price of gasoline. It is also something to consider with respect to this issue. Each time food passes up another level in a food chain, a great deal of the matter and energy is "wasted." Think of it this way, if we eat a proper diet of calories each day, we don't gain weight. The food taken in is converted into new tissue to replace old, and energy to sustain our activities, but much of it is "lost" in the form of wastes and dissipated energy. As I used to tell my students at the old Toyon school, "You are what you eat... minus what you excrete." Each time food passes from one organism to another, there is an energy loss of about 90% so eating a kelp bass rather than an equivalent weight of sardines is far less energy efficient when viewed from the perspective of the ecosystem itself. It would be better if we humans ate the 14 million tons of anchovies rather than inefficiently turning them into another source of food. Of course it would be even better if we left much of them in the marine world where they will feed their natural predators rather than pigs and chickens!

I was once vegetarian. However, my cooking left much to be desired... and still does. It is good to eat low on the food chain. There is no question the impact of Homo sapiens on the world's ecosystems would be much lower if we all did. I do alternate my dinners of fulfilling flesh with ones of higher efficiency vegetables. However, vegetarians have only a little high ground over us omnivores and carnivores in terms of their effects on the marine environment. At least that's my story... and I'm sticking to it. Oh, and so is the food in my frying pan.

© 2008 Dr. Bill Bushing. Watch the "Dive Dry with Dr. Bill" underwater videos on Catalina Cable TV channel 49, 10:00 AM and 5:00 PM weekdays and on Charter Communications Cable channel 33 at 7:30 PM on Tuesdays in the Riverside/Norco area. Please help me climb out of self-imposed poverty... buy my DVD's (see this link). Yes, take Dr. Bill home with you... we'll both be glad you did!


Anchovy, fish meal from baitfish dried and ground up to feed "farm" animals and, eventually, us...
but better as anchovy in a tin can than as pork or poultry.

This document maintained by Dr. Bill Bushing.
Material and images © 2008 Star Thrower Educational Multimedia