Agroecology and aquaculture: Linking fish and vegetable production systems

Background/Question/Methods

Aquaponics is the mutually beneficial integration of hydroponics (e.g., soilless systems for crop production) and aquaculture (e.g., aquatic animal farming) to simultaneously produce plant and animal products. Aquaponic systems mimic natural systems where aquatic animals excrete waste, bacteria convert the waste into nutrients, and plants remove the nutrients and improve water quality for the aquatic animals. Since the 1970s, aquaculture researchers have experimented with raising fish in land-based tanks with continuously recycled water, called recirculating aquaculture. A major challenge for recirculating aquaculture was the accumulation of nitrogen compounds, a potentially toxic by-product of fish waste. Aquaponics can be used as a means of removing nitrogen compounds from recirculating aquaculture, and produce a second profit center in the form of edible plants. No peer-reviewed published studies have attempted to estimate the number of aquaponic systems in use and what methods are being employed. This study was conducted to fill this research gap by documenting the production methods, experiences, motivations, and demographics of aquaponics practitioners. An online survey was used to collect information about aquaponics practitioners in the US and internationally. 

Results/Conclusions

Eight hundred and nine respondents meet the inclusion criteria for the study. Respondents were from the US (80%), male (78%), and had at least a high school degree (91%). The mean age of respondents was 47 ± 13 years old, which is 10 years younger than the average US farmer.  Most respondents (52%) had less than three years of aquaponics experience. Respondents typically raised tilapia or ornamental fish and a variety of leafy green vegetables, herbs, and fruiting crops. Respondents were most often motivated to become involved in aquaponics to grow their own food, for environmental sustainability reasons, and for personal health reasons. Many respondents employed more than one method to raise crops, and used alternative or environmentally sustainable sources of energy, water, and fish feed. In general, our findings suggest that aquaponics is a dynamic and rapidly growing field with participants who are actively experimenting with and adopting new technologies. This survey is the first large-scale effort to track aquaponics in the US and provides information that can better inform policy, research, and education efforts regarding aquaponics as it matures and possibly evolves into a mainstream form of agriculture.