Going Back to Nature

Part of the reason that livestock and fish farms have become ecological disasters is that they have moved away from mimicking the environment in which animals exist naturally. Decades ago, before the big jump in production, livestock played a symbiotic role on

Meat and Seafood: The Global Diet's Most Costly Ingredients most farms—grazing on cropland before or after production and providing essential fertilizer in the form of manure. Fish ponds occupied a similar place on most farms, feeding off of agricultural waste and helping to enrich soil. But once farmers removed livestock and fish production from the land, the need for inputs jumped and the manure began to pile up.7

In places as diverse as the Philippines and Iowa, some farmers are going back to more traditional methods of farm animal production. Outside Manila, for example, innovative farmers have learned from the centuries-long practice of raising livestock and fish together. By rearing hogs, chickens, and tilapia and by growing rice, these farmers have created a self-sustaining system: the manure from the hogs and chickens fertilizes the algae in ponds needed for both tilapia and rice to grow. And in central Iowa, pig farmers are remodeling "conventional" concrete sheds for raising pigs into open areas with deep bedding and outdoor access and raising heritage pig breeds, like Berkshires and Tamworths. These breeds are more used to living outdoors, and because they are allowed to forage, their meat is tastier and healthier than factory-farmed pork.8

Outside Manila, innovative farmers have learned from the centuries-long practice of raising livestock and fish together.

These farms produce very little waste, provide a diversity of food, and give farmers a much needed sense of both food and economic security if prices for meat or fish fluctuate. The farms also cut down on veterinary costs: Animals that are raised outdoors rarely suffer from the respiratory ailments and other illnesses common in factory farms. And because farmers raising grass-fed animals have fewer of them than factory farms do, they are much better at spotting and treating sick and injured animals and at preventing potential pandemics like avian flu.9

Of course, going back to a more traditional way of raising meat and fish is not completely practical. Many people who used to farm have moved away from the countryside, and farms are bigger and more concentrated than they once were, all of which makes it hard to return to a more integrated form of production. But meat and seafood farmers around the world are mixing a dose of old-time practices with certain lessons from modern ecology and showing that they can raise just as much food, while greatly reducing the harm caused by their farms.

For years, for example, the pig industry has said that gestation crates—concrete stalls that do not allow pigs to move much, turn around, or act in other natural ways—are the most economical way of meeting demand for pork products. But recent Iowa State University research that compared the costs of raising sows (female pigs) in gestation crates and alternative structures found otherwise. Instead of confining pigs in crowded factory farms, the researchers reared sows in group hoop houses—pens that allow the animals to nest in straw and walk around freely. A two-year study found that sows in hoop houses had more live births than those in confinement facilities. Researchers also found that group housing could reduce production costs by as much as 11 percent compared with gestation crates. Pigs are not only very social creatures, but when allowed to nest together they can better control their own temperatures, which can improve overall health and performance, the researchers claimed.10

This type of mangement-intensive farming will also create more jobs. According to agricultural economist William Weida, one reason factory farms claim that they are profitable is that they need fewer people to take care of the

Meat and Seafood:The Global Diet's Most Costly Ingredients animals. But recent evidence indicates that when animals are well cared for they perform better. Smithfield, for example, the world's largest pork producer, found at one of its hog farms in Mexico that productivity increased when they had more people tending the pigs. These practices are part of a much wider movement toward humanely raised and environmentally sustainable products from animals that were raised on grass.11 Raising cattle, cows, pigs, and chickens— and raising fewer of them—in more natural environments also has some significant benefits for what is likely the most pressing environmental issue today: climate change. Researchers at the University of Wales are looking at how introducing different grasses—which are what ruminants are meant to eat—into cattle diets can help reduce the methane emissions from belching, flatulent cows. While the diet fed to cattle and dairy cows on factory farms encourages them to gain weight quickly, it also leads to a variety of digestive problems. Scientists believe that more-digestible feed will reduce these problems and thus help curb methane emissions. Not surprisingly, some of the grasses found commonly in U.K. pastures and meadows— including white clover, rye, and a flower called bird's foot trefoil—are highly digestible. And a Swedish study in 2003 found that beef cattle raised organically on grass emit 40 percent less greenhouse gases and use 85 percent less energy making beef than cattle raised on grain.12

While improving meat farming largely means moving animals out of grain-focused feedlots and back onto the land, the simplest way to reform fish farming is by moving back down the food chain toward species that do not require as much fish feed. As seafood producers have begun farming fish to compensate for the depletion of wild fish stocks, farmed fish have grown to account for 40 per cent of all seafood eaten around the world. Industry analysts suspect this share will be well above half in the next few years. But much like the move to concentrated factory farms for meat, fish farming has been transformed from its ancient roots of efficiently reusing vegetable scrapes, weeds, and manure to raise a few carp or catfish.13

The closely confined fish on industrial farms require massive inputs of feed, energy, and biocides to control disease, while also generating large amounts of manure. Today, fish farmers raising tuna, salmon, striped bass, shrimp, and other carnivores consume considerably more fish—anchovy, herring, capelin, and whiting—in the form of feed than they produce. In 1948, only 7.7 percent of total marine catch was reduced to fish-meal and fish oil. Now about 37 percent of global landings are reduced to feed, eliminating an important historical and future source of human sustenance.14

Understandably, farmers raise carnivorous fish like salmon, tuna, and cod in large open-ocean pens because of the high prices these fish command. Only a shift in taste by consumers will help push farmers toward raising more-efficient species like carp and catfish as well as shellfish. In the short term, however, fish farmers are at least starting to move—in line with the urgings of various concerned citizens' groups—in a better direction.15

Consider salmon, the first species to be raised in fish farms on a large scale. Several decades of production in nations like Chile, Norway, and the United States have shown that such farms also lead to large amounts of coastal pollution from waste and excess feed, the use of antibiotics and other chemicals to control disease, and the occasional escape of millions of salmon into nearby waters, where they often spread disease to remaining wild salmon.16

In response, the National Environmental

Meat and Seafood: The Global Diet's Most Costly Ingredients

Trust and other conservation groups, fishing organizations, and marine scientists launched the Pure Salmon Campaign. The group has eight primary areas—such as waste, disease, and escapes—that they encourage salmon farms to address. In particular, the campaign has been lobbying for a move toward closed-container farms, so that water can be reused and any pollution from the fish can be treated and kept out of the surrounding waters. And they have started lobbying the world's largest salmon farming companies—including Marine Harvest, which controls more than 20 percent of global production—with a combination of shareholder resolutions and direct negotiations with corporate boards. Most recently, they helped convince Marine Harvest's largest shareholder (an avid angler for wild salmon) of the importance of closed-container farms.17

In many densely populated Asian nations, where demand for seafood is growing fastest, fish farming is a natural addition to existing rice farming operations.

But what about the high feed requirements in salmon, shrimp, and other carnivorous fish farms? Borrowing principles from ancient fish farms that raised several species of carp that each fed on a different plant or that combined ducks, fish, snails, and other organisms that fed off each other, integrated farms can reduce feed requirements and waste while generating more edible seafood than a fish monoculture does. While large-scale applications are still relatively few and far between, raising salmon with bottom-feeding fish, mussels, sea urchins, or algae can help eliminate most nitrogen "leakage" from the salmon, while also producing other harvestable crops. (Mussels actually grow 50 percent faster near salmon pens.)18

In Norway, several large farms have found that introducing cleaner fish—a species that cleans parasites and leftover food off other fish—into salmon pens dramatically reduces lice (the major disease of farmed salmon, which also has been spreading to and decimating wild salmon throughout the world) and feed wastage (as the cleaner fish scavenge what the salmon miss) and that the cleaner fish can later be harvested to turn into fish-meal. Salmon production remains the same while waste drops by more than half, the incidence of disease drops, and the farm harvests two or three additional crops.19

Because oysters, clams, scallops, mussels, and other shellfish eat algae and can help filter and reduce excess nutrients that run into the water and promote algae blooms, coastal communities around the world are using shellfish farms to remove nutrients from bays, rivers, and coastal waterways. Studies have shown that enhancing shellfish beds is a cheaper way to remove nitrogen from the water than sewage treatment plants. This allows sunlight to reach the bay bottom so that grasses and the other bases of the food chain thrive. "By providing these three services—filtration, stabilization and habitation—oysters engineered the ecosystem," wrote shellfish expert Rowan Jacobsen in A Geography ofOysters when describing the historic role of oysters in places like the Chesapeake Bay on the east coast or Puget Sound in the west.20

A return to oyster farming could not only result in lots of new jobs and shellfish to eat. It might actually be the best way to restore inland estuaries, coral reefs, and coastal ecosystems damaged by pollution, including the more than 200 large dead zones that have been caused by excess nutrient runoff. Moreover, the metal cages that hold the shellfish in these operations function as artificial reefs. Fishers have learned that striped bass, shad,

Meat and Seafood:The Global Diet's Most Costly Ingredients and other species congregate around them.21 In many densely populated Asian nations, where demand for seafood is growing fastest, fish farming is a natural addition to existing rice farming operations. This isn't new. Arche-ological evidence shows that Chinese farmers have been raising fish in rice paddies for nearly 3,000 years. Vegetable scraps and crop residues are fed to fish, which in turn produce waste that is used to fertilize the fields. Farmers can also use fewer pesticides and herbicides, since fish help control pests by consuming the larvae and eating weeds and algae that compete with rice for nutrients. (Fish farming also helps to control malaria, since fish eat mosquito larvae.)

Farmers practicing rice-field culture in Bangladesh have managed to reduce production costs by 10 percent, and the average farm income has increased by 16 percent in just three years, buoyed by sales of fish fry and fingerlings as well as of fish that farmers do not eat. One hectare of rice field typically produces between 250 and 1,500 kilograms of fish. Thousands of rural Bangladeshis have already adopted this form of affordable aquaculture. And researchers suggest that farmers could quickly adapt this integrated system on about 40,000 hectares, generating 10,000-60,000 tons of fish, worth roughly $40 million a year.22

Such benefits are not restricted to Asia. A recent project that focused on increasing production at several hundred small-scale fish farms in Cameroon found that basic technical assistance—including regularity of feeding, proper stocking densities, and a harvest schedule—boosted production from 498 kilograms to 2,525 kilograms of fish per hectare and increased cash returns 16-fold. The researchers estimated that in areas with good market access, similar investments could add 5,300 tons of fresh fish to the food supply, put an additional $50 million into the local econ omy, and produce profits for each farm in the range of $2,000 a year—twice the average income per person.23

0 0

Post a comment