Official "Fowling Our Nest" Thread

[ewmayer]

There have been discussions about human population and consumption growth at several points in the past around here. after looking for an existing thread appropriate for posting the story below, I decided that topic, like global warming, merits a dedicated thread.

The Unsustainable Protein Pyramid of Forage Fish

Per capita meat consumption more than doubled over the past half-century as the global economy expanded. It is expected to double again by 2050. Which raises the question, what does all that meat eat before it becomes meat?

Increasingly the answer is very small fish harvested from the ocean and ground into meal and pressed into oil. According to a new report by scientists from the University of British Columbia and financed by the Pew Institute for Ocean Science, 37 percent by weight of all the fish taken from the ocean is forage fish: small fish like sardines and menhaden. Nearly half of that is fed to farmed fish; most of the rest is fed to pigs and poultry.

The problem is that forage fish are the feedstock of marine mammals and birds and larger species of fish. In other words, farmed fish, pigs and poultry — and the humans who eat them — are competing for food directly with aquatic species that depend on those forage fish for their existence. It’s as if humans were swimming in schools in the ocean out-eating every other species.

The case is worse than that. When it comes to farmed fish, there is a net protein loss: it takes three pounds of fish feed to produce one pound of farmed salmon. This protein pyramid — small fish fed to farmed fish, pigs and poultry that are then fed to humans — is unsustainable. It threatens the foundation of oceanic life.

The report’s authors suggest that it would be better if humans ate these small fish, as many cultures once did, instead of using them as feed. That is one way of addressing the problem of net protein loss. The real answers are support for sustainable agriculture in the developing world and encouraging healthy, less meat-based eating habits as a true sign of affluence everywhere.

My Comment: ...Or maybe we humans should make a serious effort to curb our out-of-control gluttony and reproduction. Note the dangerous "benefits of economic development" irony here: Speaking very broadly, the part of world whose fecundity is within manageable bounds is doing disproportionately much of the eating, and the part of world whose gluttony is within manageable bounds [albeit often not by choice] is doing disproportionately much of the reproducing. And so it goes.

[cheesehead]

So, which readily-available-to-consumers non-top-of-foodchain fish species are not overfished or in danger of being so?

[Uncwilly]

See this post: http://www.mersenneforum.org/showpos...&postcount=125

[geoff]

The same sort of problem applies to all agriculture. If you can grow enough plant protein to feed yourself on a plant diet from X units of land, then you need 20X units of land to grow enough plant protein to feed enough cattle to feed yourself on a beef diet. Fish and fowl are a lot more efficient than cattle and pigs, but most efficient of all is simply to eat the plants directly and avoid the waste involved in passing them through a farm animal first.

[cheesehead]

Originally Posted by geoff

The same sort of problem applies to all agriculture.

< snip >

most efficient of all is simply to eat the plants directly and avoid the waste involved in passing them through a farm animal first.

I agree, but wish to point out that some land is naturally far more suited to raising livestock than to growing plant crops.

In the central Texas "hill country" the native grasses are three feet high, but each blade has a barb on the end that will go through any fabric thinner than blue jeans, cockleburrs and thistles will decorate your socks after any stroll in street shoes, and the hilly ground is stony. (Naturally, one avoids stepping on the cactus and rattlesnakes.) Summers are too hot and dry for anyone to grow more than a home-garden's worth of vegetables (with small-scale irrigation from windmills). However, cattle grow well on these lands and ranchers can make a good living from them. (That's beef cattle, not dairy cattle. Milk from a Jersey grazing there comes out bitter from the weeds that taste good to the cow.)

Now, in modern times, after they go from ranch to stockyard those beef cattle are further fattened on ... whatever (used to be just low-grade corn) ... (and that's a topic of its own), but still they (and goats) are basically the most productive agricultural product for that type of land.

[Uncwilly]

Originally Posted by cheesehead

but still they (and goats) are basically the most productive agricultural product for that type of land.

And if it were wetlands instead, we could dry it out and raise crop xxxxx.
The concept of putting every last hectare into production is not valid. As evidenced by the decline of spieces due to loss of habitat, certain land needs to be protected from agriculture. Areas like the Everglades, the mangroves around the Mississppi delta, rainforrests, etc. are so much more valuable to life on this planet in the natural state rather than under the plow.

The typical figure of plant to animal ratio is 5-10 to 1. If the typcial American were to eat only "sustainable" red meat (which includes bison) and more meat of bovid origin, there would be more land available for grain (not the best choice) or other crops. "The solution" is far more complex than saying 'Don't eat this' or the like. Eating of things like desserts is again more destructive to the environment than one might think. The area in Brasil or Hawaii taken from the rain forrest to grow cane for the sugar, the land for the milk, the land for the wheat, and the land for the feed that goes into the eggs; all of these add up to far more harm than growing a simple fruit, like an orange, bannana, or apple. I won't get into the green house gasses produced in the production. The selection of what and how much one eats is part of 'going green'.

[/rant]

[ewmayer]

Originally Posted by geoff

The same sort of problem applies to all agriculture. If you can grow enough plant protein to feed yourself on a plant diet from X units of land, then you need 20X units of land to grow enough plant protein to feed enough cattle to feed yourself on a beef diet. Fish and fowl are a lot more efficient than cattle and pigs, but most efficient of all is simply to eat the plants directly and avoid the waste involved in passing them through a farm animal first.

True [albeit rather simplistic, as most Utopian-vegetarian arguments are], but I proceed from the assumption that given our evolutionary history, there will always be a goodly fraction of meat eaters among us.

But given the "inefficiency" involved in processing non-meat foodstuffs into meat, the way to go is to eat meat and fish derived directly from inedible-by-humans feedstocks, e.g. cattle eating grasses and fish eating plankton and krill. Iterating the process so that high-quality protein gets cycled into less of same is not only extremely wasteful, but - as the history of prion diseases shows - can be quite unhealthful.

[Fusion_power]

The amount of arable land is pretty much a fixed quantity, the human population is dynamic and growing. The underlying question behind this issue revolves around the overall human population growth which is projected to be at 10 billion within 50 years. In very realistic terms, the earth can support a maximum of about 50 billion humans but with severely degraded quality of life.

If you read my website at http://www.selectedplants.com/ you will find that I grow a huge part of my food in a garden and I also produce several hundred dollars of seed that goes into the chain for other people to produce their own food from plants. My garden this year was rows about 100 feet long with 5 rows of pole beans, 5 rows of corn, 12 rows of tomatoes (600 plants), 3 rows of peanuts, 3 rows of cowpeas, 2 rows of okra, 1 row of potatoes, and a wide area with watermelon, cantaloupe, squash, and gourds. I had a few sweet potato plants, some turnips, and for the fall, I have some collards. There are probably a few other things I missed.

My point is that on 3/4 of an acre, I produce enough food that with minor supplements is able to feed one person very well and still produce surplus seed that helps feed lots of other people. I am not a vegetarian so I do buy meat to go with the veggies.

We can all talk about 'sustainable' agriculture. I'm doing a huge amount to live it. The problem is that our population today is very much urban vs the rural lifestyle prevalent 100 years ago. It would be very difficult for the average family today to produce even a reasonable percent of the food consumed.

DarJones

[xilman]

Originally Posted by Fusion_power

If you read my website at http://www.selectedplants.com/ you will find that I grow a huge part of my food in a garden and I also produce several hundred dollars of seed that goes into the chain for other people to produce their own food from plants.

Fascinating site and thanks for the link.

You are fortunate to live in a climate where tomatoes grow out of doors easily. Up here in the sub-arctic only the relatively hardy and quick-growing varieties produce a worthwhile crop out of doors. All the rest need protection.

My wife grows a few tomatoes in pots each year but I'm not a great tomato fan. (BTW, growing basil in the same pot does wonders to protect them from aphids.)

What I do like growing are chillies. They do well in pots which can be brought in for the winter if the plants are to be saved. We grow roughly twice as many fruit each year as we can eat, even after a good fraction has been converted to harrissa. The surplus are given to friends, family and cow-orkers.

Paul

[cheesehead]

Originally Posted by Uncwilly

And if it were wetlands instead, we could dry it out and raise crop xxxxx.

Is there a connection between wetlands that would need drying out to be agriculturally productive, and central Texas or similar land that doesn't need drying-out or irrigation to be commercially productive?

Modifications that central Texas does need, more or less, are:

1) for every few hundred acres of pasture, construct an acre-sized watering pond by damming up one of the small natural water runoff paths (dry except after rains),

2) every decade or so, bulldoze over the mesquite trees in a pasture (disturbing only the soil occupied by mesquite roots) to a) allow the livestock to eat the mesquite "beans" and b) increase the grassy-area-to-mesquitey-area ratio (mesquite is not endangered and its wood smells great when burned for cooking),

3) for those so inclined, plow up a half-acre-to-acre next to the house for a home vegetable garden. Water from windmill when rain is scarce.

As evidenced by the decline of spieces due to loss of habitat, certain land needs to be protected from agriculture. Areas like the Everglades, the mangroves around the Mississppi delta, rainforrests, etc. are so much more valuable to life on this planet in the natural state rather than under the plow.

The areas you cite are all wet, rather than dry like central Texas. Raising pasture-fed cattle does not require land modification other than ~1% as noted above.

[geoff]

Originally Posted by cheesehead

In the central Texas "hill country" the native grasses are three feet high, but each blade has a barb on the end that will go through any fabric thinner than blue jeans, cockleburrs and thistles will decorate your socks after any stroll in street shoes, and the hilly ground is stony. (Naturally, one avoids stepping on the cactus and rattlesnakes.) Summers are too hot and dry for anyone to grow more than a home-garden's worth of vegetables (with small-scale irrigation from windmills). However, cattle grow well on these lands and ranchers can make a good living from them. (That's beef cattle, not dairy cattle. Milk from a Jersey grazing there comes out bitter from the weeds that taste good to the cow.)

A similar argument is heard here from sheep farmers in the South Island high country: Even if some human edible plant could be grown there, no harvesting system could ever compete with the combination of sheep + sheep dog.

But if humans ate plants instead of sheep then there would be no need to have such marginal land in production anyway, more than enough plant food could be grown for direct human consumption on the easily accessible and much more fertile lowlands.