INTRODUCTION
The last 15 years has seen a dramatic increase in Texas shrimp farms and their productivity. This paper investigates how the current aquaculture boom affects the coastal regions and some possible alternatives to the negative impacts the growing industry is creating. The main focus of this work however, is the disappearing coastal habitat and the effects the shrimp farming industry is having on local human residents as well as the other species that share the coastline and surrounding water bodies. A startling statistic from the Environmental Defense Fund reports 51,373 predator bird species were killed between 1989 and 1993. The reason for the predator bird mortalities is due to the birdsÕ feeding on the Ôeasy pickingsÕ that aquaculture provide. These are only the reported statistics of authorized kills (EDF 1996). There are non-lethal methods available to deter predation on aquaculture systems which will be addressed in the opportunities aspect of this investigation.
Shrimp productivity, (or any production instigated by people) historically has been based solely on the limiting factor of technology. Shrimp acquisition for human consumption today cannot be sustained by the world's seas (Boyd 1995). Seventy percent of the earth's surface has reached it's carrying capacity, including the oceans. This very fact is a tremendous reflection of influence the human race poses to the earth's cycles.
Farmed shrimp maintains approximately 27% of the worldÕs consumption (Primavera 1997). Many farms in Asia are family / community run; known as extensive operations. The practice of extensive production depends on the surrounding rivers or bays; thus they are dependent upon outside sources for replenishing their genetic pools, water quality, and nutrient supplies. Though the Asian aquaculture technology has been highly successful for generations, it is not usually considered a "closed system". The idea of a closed system means that the production is self sustaining without harming the surrounding environment. For generations people have thought of the world's oceans as an endless resource to harvest at will; thus an open system. It is our generation that is witnessing what is being called the end of the 'Empty Earth' (Goodland and Daly 1996). Unless it is completely self sustainable, aquaculture in general can have harmful effects on the neighboring environments. A degrading environment is quite apparent to local inhabitants and detrimental to niche specific animals. Texas is the focus for this current shrimp aquaculture study since it is currently the number one producer in the United Sates for farmed shrimp. American agriculture has historically taken from the environment without too much pay back, and this is the case for the blooming aquaculture trend as well. Linear harvest can no longer be the case if we are to build a sustainable environment for the next generation. Productivity worldwide is being looked at in new and innovative ways.
Coastal Impacts
The last fifteen to twenty years has seen a boom in shrimp aquaculture in Texas. "Economically successful shrimp aquaculture" has taken over four of the seven major estuaries along the Texas coastline (Baker 1997/Mcfarlane 1998). Because of the current practices, one of the negative impacts to the Texas estuaries is the introduction of an exotic species of shrimp. Penaeus vannamei, white shrimp, is preferred by farmers over the native brown (McFarlane 1998). This non-native has already invaded two of the larger estuaries. Non-native species can have traumatic effects on indigenous animals and ultimately change the local habitat. To understand how and why exotic introduction occurs, shrimp farm operations must be viewed.
Most shrimp farms are open systems; which means that at some point in the production it is necessary to utilize wild shrimp to restock the existing stores. "Post shrimp" (immature or larva) are captured from surrounding waters or are produced in hatcheries. Then they are mixed with broodstock caught from the ocean. From this union, larvae are produced and raised in the hatchery tanks (Boyd 1995).
There are three major types of shrimp aquaculture; extensive, semi-extensive, and intensive farming. The Americas, particularly the US, uses high-intensity shrimp farming. Large ponds up to fifty acres with a depth of three to six feet are the norm. These farms produce a tremendous amount of shrimp, but are highly susceptible to epidemics and disease. Extensive and semi-extensive farming practices have a lower productivity over all but use less costly feeds, utilize more human labor and are economically more feasible for small family operations. Shrimp aquaculture systems in Texas as well as other major shrimp producers are having to address these new and challenging concepts. Currently, lenient, ambiguous regulations specific to Texas has allowed growth without consequence. No protection for the receiving waters, added to the tremendous growth in shrimp farms, illustrates the pollution problem complexities along the coastline. TexasÕ current Water management practices or lack thereof is a graphic depiction of non sustainable aquaculture (McFarlane 1998).
SOCIAL ASPECTS
Pollution
One social aspect that is currently being raised is the point /non-point source pollution problem. Intensive shrimp farms create enriched nutrient plumes that are currently being studied to determine the harmful effects they may generate. One of these studies occurring right now is a cooperative effort between the Texas Agriculture Experiment Station (TAES) and Texas A&M (Kingsville and Corpus Christi Universities). Their combined efforts are addressing water quality and methods that can improve current water conditions (TWRI 1997). This study is significant because it is specifically addressing total suspended solid (TSS) content in the water column as well as biochemical oxygen demand (BOD) in the effluent. Hopefully, TAES and Texas A&M will shed light on the absolute necessity of changing the discharge practices that are currently in place. Water clarity and specific nutrient conditions are necessary to sustain the native shrimp and other crustacean populations throughout the Gulf of Mexico. Private as well as corporate systems have complained of the negative effects of the shrimp farms discharging untreated effluent to the local bay, which is customary for Texas' coastal farms to pump water from the bay, circulate it through the hatchery and discharge directly back into the surrounding waters without treatment. This is due to the fact that only one out of six farms in 1996 actually had permits from the state to discharge their effluent. (Baker 1997).
Another factor not well studied is the escape of non-natives into the endemic environment (Baker 1997). It is still debatable whether this brand of 'pollution' is a severe negative effect or not. This reasoning is mostly due to inconclusive, or rather, disagreeable data. There have recently been data that show exotics released into four of the seven major estuaries, including Laguna and Matagorda Bays. The non-native caught was the Panaeus vannamei, the local farmersÕ exotic favorite (McFalrane 1998). These factors have ignited competition with off-shore corporate and private harvesting, who have also been contributors to the growing problems of the coast and surrounding gulf. Over fishing of the areas, and trawling bycatch, (which produces a large number of kills in non-targeted species) are the major points of impact. regulation and limited permits for fishing the gulf have hit the small independent shrimpers the most. New techniques such as Òbottomless netsÓ have begun to turn the tide. Bottomless nets have a large area of net removed from the trawlÕs underside. When used in estuaries, the nets do much less damage on the oyster reefs (Martinez 1193). For centuries these estuaries have been the nurseries for the majority of the Gulf's marine species; the urgency to protect these areas is obvious.
Foreign Investors
New on the list of social conflicts is the invasion of Taiwanese Farmers. Asian countries with Taiwan as the leader in aquaculture have historically produced shrimp in a Òboom-and-bust cycleÓ (Pimavera 1997). Production in Taiwan moved to intensive farming practices after multinational corporations aided the growth of the industry. Growth of this nature began around 1989; previously shrimp production was extensive, utilizing natural food and water sources as well as large amounts of human labor. Extensive farming has a much lower impact on the environment. Unfortunately, Intensive farming has become the norm and is the major system used now in the United States. Taiwanese investors began investing in Texas after the fall of some Asian farms due to disease and pollution. Poor aquaculture techniques has created outrage among local citizens who are taking it upon themselves to watch and report discharge violators (EDF Murky Waters). In addition to crowding the coastline with more farms, most investors make their money and send it back to the home country; thus utilizing the environment but not allowing the revenues to be felt in the US. Typically, the United States has been doing this all over the world for many years. Selfish acquisition of resources is not an isolated incidence, but an antiquated technique to Ôget rich quickÕ. Future aquaculture in Asia as well as the United States must shift gears into closed system productions if the industry is to survive.
Dams: CanÕt Live With Them / CanÕt Live Without Them
Lastly, Physical impoundments such as hydroelectric dams, Specifically affecting the Sabine and Neches rivers, have created reservoirs that stop natural sedimentation deposition and nutrient flow fluctuations. With dams comes water flow changes, which produce devastating effects on all aquatic and surrounding wildlife, not only the shrimp farms downstream. One example of the negative impacts of dams can be seen at Sabine Lake. The Toledo Bend Hydroelectric plant increased flow rates during the summer of 1996. The unnatural increased flow resulted in the crash of the Sabine Lake White Shrimp Fishery. (McFarlane 1996). As more of Texas and the rest of the worldsÕ waterways are harnessed for hydroelectric power, People as well as the environment will see and suffer the changes that are being inflicted.
It is obvious that Shrimp farming in Texas is growing with the demands of the public. But it is also the public who is demanding regulation and control over the negative impacts of these farms. Hopefully as Texas increases itÕs regulations and monitoring, it will also give farmers incentives to become more efficient and environmentally consciences. It benefits everyone eventually.
TECHNICAL ASPECTS
Shrimp Farm Basics
There are three major production methods used in shrimp aquaculture: Extensive, semi-intensive and intensive practices. Intensive farms are the norm for Texas. Intensive farming is high yielding, often producing export values of $45,000/acre per year, but high costs go hand in hand with those big profits. Construction, stocking and feed investments range from $5,000-$20,000 per acre (Boyd 1997). It might be five years before an intensive production facility will be out of the red financially, provided there are no major losses or set backs due to weather conditions or diseases. Examination of intensive farming is necessary in understanding these current monetary figures as well as seeing the possible problems that accompany the intensive production.
First, shrimp growing requirements must be understood to produce a crop. Nutrients, algae, detritus and clean water are basic necessities for shrimp to live. Food and its cost is a major factor in intensive systems. Not so for extensive production. Raw material already existing in extensive ponds serve as the food source for the growing shrimp. Stocking rates in extensive ponds are approximately 10 to 20,000 postlarvae (immature shrimp) per acre. Some supplemental foods might be necessary but these farms are usually not labor intensive or high maintenance. Intensive farming is just that: Intensive. Stocking rates for TexasÕ Intensive production ponds are over 100,000 postlarvae per acre. Cramming individuals together (specifically monoculture overcrowding) creates perfect conditions for rampant disease. To off set this constant potential problem, farmers buy Specific Pathogen Free postlarval shrimp. SPF is a general term used to identify captive species; this does not mean that SPFs are Ô domesticatedÕ (Baker 1997). The SPF larva are imported from growing facilities, so the stock being raised are not native to the local environment, posing possible exotic contaminations to surrounding waters. SPF larva also cost a great deal more than local broodstock, and have to be supplemented with additional foods, vitamins, minerals and antibiotics.
Intensive systems may have an intermediate step in their process. Some farms stock postlarval shrimp in Ònursery pondsÓ until they reach the juvenile stage of their life cycle. This is a smart practice; when a farmer pays premium price for PLs., a nursery phase in the early part of their growth assures more shrimp make it to the outgrow ponds.
A look at the native shrimp life cycle sheds light on the reasoning behind nursery ponds.
To ensure postlarvae reach adulthood, measures must be taken to protect the immature shrimp from predation. To ensure profitable harvests, adult shrimp must be protected as well. Birds are the biggest threat to shrimp farms next to disease. Many species are drawn to the farms because of the easy prey available. Costly non-lethal deterrents have limited success(ENN 1998); which often leads farmers into lethal methods of protection.
There are many different methods including built in modifications to the system when it is being constructed. Other non-lethal methods may be employed to existing farms (EDF 1995).
Shrimp Life stages
The two major native shrimp species that inhabit bays and the Gulf of Mexico are the brown shrimp (Penaeus aztecus) and white shrimp (Penaeus setiferus). Both of these species spawn in the waters of the Mexican Gulf. White shrimp spawn in late spring and continue through summer. Brown shrimp spawn during the fall so there is a definite difference in there distribution and population at any given time of the year (Mcfarlane 1996). There is a small period of over lap when they both migrate into the estuaries of Texas and Mexico for protection and food; here, they will spend two to four months growing before heading into deeper water. White shrimp lag behind in the transition from gulf to estuary, staying longer in the gulf and growing larger than the brown species before drifting to the safety of the tidal creeks and bays. White shrimp make up 57% of the total of the Gulf of MexicoÕs shrimp landing (NOAA 1997). Since nature provided this difference in growth phases, it is easy to see how using native shrimp for aquaculture could result in two harvests per year. Yet farmers continue to stock imported shrimp (SPFs from Hawaii) at higher prices, with more disease preventive expenses, not to mention the responsibility of exotic introduction to the Gulf of Mexico and its bays.
Exotic Species Use
As one of the most controversial aspects of shrimp farms, exotic species use for increased production is under tremendous political fire. Initially, the Pacific Shrimp were imported for their larger body size and their ability to better exist in mariculture operations than native species. Increased body weight increases production which increases profits.
It is quite apparent that non-native farming methods are strictly Ômoney-mindedÕ. Unfortunately this linear thinking does not take into account the possible negative impacts of exotic exposure to the local habitat.
One reported accidental release of non-native Pacific White Shrimp occurred at the Hung Shrimp Farm in 1991. Hundreds of pounds of exotic shrimp were released into the Arroyo Colorado Bay, causing the farm to pay $63,000 in fines (TPWD 1997). This is only an isolated incident , but it is quite possible for non-natives to escape through current discharge practices. The total impact of these exotic injections to indigenous species is still unclear, but recent studies have shown that the viruses that are carried in the exotics can spread to the native populations (TPWD 1997). The life cycles of these two endemic shrimp may be altered forever. A disturbance of this magnitude could alter the environment further, causing kills in other species and could cause the end of wild shrimp harvests if a virulent strain of disease breaks out.
There is also a practice of using wild-caught shrimp for broodstock, but environmentalists and biologists fear this depletes natural populations and competes with fishing catches. Wild stocking is seen as a flaw in aquaculture, rendering it linear in production rather than cyclic (Boyd 1997). There also contradictions as to whether or not shrimp can be domesticated. Pamela Baker does not see SPFs as domesticated, while Claude Boyd refers to the SPF broodstock as Òlineage broodstockÓ inferring domestication. As this debate rages, importation and accidental releases are creating a gigantic experiment in the Surrounding waters of the shrimp farms.
Advantages and Disadvantages of Current Production Practices
The reasoning behind the current trend in Texas aquaculture is financially motivated. The potential profits from intense farming using the larger imported shrimp lures most farms into high maintenance and high cost production in hopes of vast monetary rewards. This one advantage does not outweigh the disadvantages. It has been found that there is a very good market for TexasÕ native shrimp, aztecus and /or setiferus, unfortunately, greed drives the wheels that ship in the vannamei (McFarlane 1998)
Imported shrimp aquaculture now being used in Texas contains a myriad of minuses. Disease is expensive to combat, and a constant threat to the dense populations. Additives such as vitamins, minerals, nutrients and antibiotics are supplemented for increased growth and resistance (Folke/Kautsky 1992). What goes into the ÒsoupÓ gets poured down the ÒdrainÓ. Most of the additives that are used in shrimp farm systems find their way into the ecosystem, degrading the surrounding water environment.
Water quality is a major issue concerning farms, families and fishing people. Not much is happening in the way of regulating discharge of effluent to nearby waterways. Understanding the water pollution potential of shrimp farms is essential if regulations are to be effective and fair.
Water Discharge Practices
In 1997, only one out of every six farms on the Texas coast had a permit to discharge the effluent water from their farms into a water body. Only two farms have facilities to test their effluent. The practice of illegal dumping of wastewater can easily be seen as a major problem when the amounts of water being affected are known. For intensive shrimp farming it is not unusual for a system to exchange 30% of the total water used of the farm (Baker 1997). Consider the contents of effluent from intensive farms: high total suspended solids (TSS), pesticides (including but not limited to) malathion, parathlon, azodin, paraquat, endosulfan and butachlor, antibiotics such as oxytetracyclin, erythromycin, and terramycin are all part of the mix. Combine these compounds along with eutrofied water and the recipe could be mistaken for a municipal wastewater influent (Hagler 1997). Health risks to local communities is gaining recognition. Individuals involved with their environment frequently are to sole monitoring system in place. The more pressure people put on their neighbors who are fouling communal waters, the more regulations will eventually be implemented.
Discharged water from farms often have significantly different dynamics than the receiving waters. In Texas this is very complicated for salinity levels differ greatly form bay to bay to gulf (Baker 1997, McFarlane 1996). Massive variance in salinity can have devastating results on all levels of biodiversity within the effected water body. Consequences such as fish kills, mutations, and overall biodiversity loss are just a few examples of negative impacts. Specifically Arroyo Colorado, and Laguna Madre have seen losses to the sport fishing populations occurring directly adjacent to shrimp farms effluent (Baker 1997). Clarity reduction is thought to be the primary problem. Low visibility degrades opportunities for fin fish to feed, since they rely heavily on sight for food acquisition.
It is quite apparent that Ò Best Management PracticesÓ do not work, though BMPs are a beginning for farmers to address their wastewater problems (Baker 1997). There has not been sufficient evidence to date for determining the positive impacts BMPs may have. Farmers left on their own to be self regulating do not have enough incentive to clean up their water before releasing it. State and federal regulation, monitoring and enforcement is desperately needed.
PROBLEMS
Pollution
Problematic effluent regulation is one of the negative impacts mentioned in the technical aspects section. Non-point pollution is a much bigger problem than first estimated, and run-off from unusual weather often exacerbates already turbid receiving waters; but stormy weather doesnÕt just effect the environment. Shrimp farms need high clarity water for growth and metabolic activity in shrimp. Storm water that washes into production systems often carries a cocktail of pollution elements. Pesticides and fertilizer from neighboring agriculture has just as negative effects on the farms as run-off does on the environment (Boyd 1997). This oversight is due to a linear perspective which has a tendency to notice only the things that directly effect human beings. Negative impacts could be prevented if people looked at the problem as it effects the environment. Egocentric attitudes such as the one aforementioned, are a major block in re-evaluating water use regulations; and Texas definitely needs re-evaluation of itÕs water regulations.
Regulation
Texas, at first, viewed its role as a regulatory body as well as a shrimp farm promoter to bolster farming practices. 1987 was the year the Texas State Legislator exempted shrimp aquaculture from water rights permit requirements. The good luck of the Texan shrimp farmers continued with the 1989 farming act that designated shrimp farms as a form of agriculture; thereby allowing farmers a tax break. State and university technical support/ assistance was also maintained until the end of 1989 when the Fish Farming act gave the Texas Department of Agriculture (TDA) responsibility for shrimp farming aspects. The TDA never did a wastewater program (Baker 1997). Wetland impoundments such as shrimp farms greatly modify the routine of the water system. Unregulated diversions of water to farms isolates waterbodies leaving them more susceptible to pollution build ups and biodiversity loss. Point and non-point pollution negatively impacts the entire estuary, dwindling some benthic species to extinction (McFarlane 1996).
In 1997 the Texas Natural Resources Conservation Commission (TNRCC) required all shrimp farms to obtain discharge permits. Finally farmers now have to show plans for wastewater treatment. Permit procedures involving disease control and exotic species use are still being hammered out in conjunction with the efforts of the Texas Parks and Wildlife Department (TPWD) and the TNRCC.
Habitat degradation
Again, Non-point pollution from shrimp farms as well as agricultural practices create tremendous loading problems for surrounding water ways. Extra nutrients from intensive farm programs find their way into the bays and gulf, increasing algal bloom frequency and size. Specific algal blooms adhere to seagrasses, creating extra drag through the water. During storms, the weight of the algae can rip the seagrasses from their beds. Seagrass is essential to shrimp during several phases of their life cycle. Destruction of the seagrasses not only decimates native shrimp populations but negatively impacts all other coastal inhabitants that rely on the seagrass beds for food, protection, and niche specification (McFarlane 1998).
Besides seagrass bed destruction in the Gulf of Mexico, mangrove loss due to land acquisition for shrimp production is another graphic depiction of habitat elimination worldwide. Asia, Africa and South America have seen the greatest loss of mangrove stands, averaging approximately 13-15% loss in the indicated countries. It is estimated that 6.2% of the entire EarthÕs mangrove habitats have been converted to shrimp production (Boyd 1997). Mangrove destruction is a multiple problem, for mangroves in general serve as huge reserves for biodiversity, storage of sediments, and coastal protection form storms.
India also shows a tremendous loss of mangrove populations. 80,000 hectares have been lost to shrimp farms. Land acquisition has still occurred despite 60% of the population in the Indian state of Tamil Nadu is landless (Hagler 1997).
Mangrove destruction in Texas is not as serious an issue as it is in other countries. Black mangroves (Avicennia Nitida) are the only native mangroves in Texas. Mangroves make up a small percentage of TexasÕ coastline and have not yet been displaced by aquaculture programs (McFarlane 1998). Water pollution from Shrimp farms is currently more of a threat to the mangroves than physical destruction, but terrestrial shrimp farms are growing in popularity, bringing effluent contamination into the forefront of mangrove distress issues. With mangrove destruction, and water pollution increasing the end result can be seen in the loss of native species throughout the local environment. The loss of biodiversity is startling.
Biodiversity Loss
Besides human side effects such as point and non-point pollution, direct action to destroy species population occurs as a means to protect shrimp farms from predation. Between 1989 and 1993 the reported predator bird kills at aquaculture facilities totaled over 50,000 birds. 15 species of swimming birds were showing deaths, with double crested cormorants heading the list at 25,930. 8 species of wader birds were destroyed, revealing the Great Blue Heron with the highest mortality. 14 species of aerial-diver birds were affected with the Belted Kingfisher as the highest number killed at 1197, followed closely by the Ring-billed Gull at 1050 dead (EDF 1995). These are only reported kills in a four year period. By no means do the figures reflect kills not reported or a current total of the birds killed since 1995. The data also only covers aviary animals, which leaves one wondering what and how many other animals were destroyed in the name of aquaculture protection.
In the most recent report to date, the US Fish and Wildlife Service gave a department order that will allow aquaculturalists to destroy cormorants that are feeding on aquaculture production systems. The new ruling will supposedly save $20 million annually. The order includes 13 states, but farms must demonstrate a need for lethal method use, and already have in place certified non-lethal measures (ENN 1998). Non-lethal harassment programs are certified through individual state wildlife agencies and the US Department Of AgricultureÕs Animal and Plant Inspection Service. In addition to proving need for lethal use, farms must keep monthly logs. The logs will only be surveyed through telephone and/or mail contact by local fish and wildlife service departments. Minimal regulation on the new ordinance may find more than cormorants being shot. A recent study did find the cormorant population to be between 1-2 million birds. The trend in cormorant populations shows a 6-7% increase annually in the last five years. The measure to dispatch the Òcrows of the seaÓ is not intended to curb populations but to supplement non-lethal methods (ENN 1998).
OPPORTUNITIES
Effluent Treatment Alternatives
Texas and its people are improving their water use practices. Grass roots organizations are starting to monitor effluent pipes in their local areas. Since 1991 local residents have Ôminding the storeÕ by being active in their communities, talking with state agencies and requesting better regulation implementation. Regional as well as national organizations have also heard the cry and have come to aid local residents. Pressure from local and national groups moved the TNRCC to require two of the largest shrimp farms to apply for state wastewater-discharge permits (Baker 1997).
Research is also being conducted by the Texas Agricultural Experiment Station (TAES) in cooperation with Texas A&M universities. Assessment strategies are hoping to reduce pollution loading from their current rates. Other possibilities for reducing TSS and BOD levels are decreased stocking rates (which would also lower disease potentials and cut maintenance costs) and increased aeration rates. Filtration methods combined with recirculation and constructed wetlands could also curb wastewater discharges (TWRI 1997). If properly monitored wetlands may eliminate secondary treatment. The reduction of costly water restoration would add incentive and make water treatment more acceptable to aquaculturalists.
Farming Changes
New methods of stocking are on the horizon. Extensive aquaculture has been in the Orient for centuries, but it has only been a recent movement in the United States. Linear ideas are giving way to more sustainable production methods. As long as money is the motivating factor, intensive farming will be the option chosen most. Constant pressure from environmentalists and local residents is forcing farmers to look at other production methods. Settling ponds, lower stocking rates, and lower flushing rates are becoming desirable, due to the lower costs associated with these practices. Natural filtration by aquatic plants and mollusk species such as clams can also reduce discharges (Baker 1997). Discharge violations may hold heavy fines in the future as regulations increase, so Òbest management practicesÓ may be the first step in cutting effluent and being prepared for the future. Primary sedimentation ponds are an inexpensive way to handle the worst loading problems. High pollutant levels could be lowered by ponds as well as lined canals and wetland filtration (TWRI 1997).
A Chinese practice that incorporates more than one aquaculture at the same time is also starting to catch on. Poly-culture has been with China for 1000 years (Folke/Kautsky 1992). By utilizing primary producers and combining various consumers, polyculture is sustainable and efficient. The lowered costs and increased profits are very attractive to new faces on the aquaculture scene in the US. ÒEcosystems are self-designing systems. The more one works with the self-designing ability of nature, the lower the costs of energy to maintain that systemÓ (Jorgensen 1996) The previous statement could not be more true. By eliminating monoculture and implementing poly-aquaculture, farmers can start realizing profit combinations.
RECOMMENDATIONS
Shrimp farm operations in Texas have to change; this is essential in protecting the waterways. Degraded water hurts the environment and all the inhabitants, including the farms themselves. New approaches such as poly-culture, water reuse, water reclamation, and semi-extensive farming practices are just a few of the alternatives waiting to be utilized. Expensive Intensive farming not only costs the farmer, it costs the who environment.
Regulations must be reviewed and increased if current discharge practices are to cease. Unfortunately, mandatory control by an outside entity may be necessary if Òbest management practicesÓ are ineffective or just not being used.
Nature by itself is highly productive and efficient. If the values of Nature and societies needs are not balanced, short term profits will become long term environmental disasters. Reduction of wastes and recycling of resources means more steps closer to sustainablity. The true challenge is to move from intensive monoculture to extensive poly-culture (Folke/Kautsky 1992). Patience is a virtue that pays. LetÕs not pay the bill of environmental and social damage, the cost is too high.
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