Black Soldier Flies as a Value-Adding Tool within Organic Farming Systems
The production of free range organic poultry is economically and sustainably challenging for producers. The extended growing period required to raise mature, free range birds is generally twice that (12 weeks) of those raised in industrial chicken houses (6 weeks). Because birds are kept longer, all associated costs are higher per bird. Although free range poultry do receive a portion of their diet from their environment they also must be provided a supplemental feed in order to receive enough nourishment for proper development. The cost and availability of commercial organic feed can fluctuate with market demand and is generally more expensive than industrially suited feeds. In order for organic farmers to be competitive in raising free range poultry they must find ways to lower their operating costs. By developing a lower cost, higher protein organic feed source, theoretically poultry could be raised to maturity faster, thus reducing operating expenditures.
White Oak Pastures currently utilizes a system of rotational grazing under the Serengeti Model in which cattle, sheep, turkeys, and chickens are allowed to graze following one another in the same pastures in a way that mimics the simplicity of African grasslands and the way animals interact with the land. Additionally, compost produced from the on-site beef processing facility waste is applied to the fields to enrich the soil, native grasses, and hay. The farm seeks to strengthen this system by utilizing eviscerate, a zero value by-product of beef processing, to grow black soldier fly (Hermetia illucens, BSF) larvae, a low-cost organic supplemental feed source for free ranging poultry. Providing additional natural feed through the BSF program will help to eliminate one of the few remaining gaps in the model. Black soldier flies are a native, non-pest fly species, are not vectors of human disease, and have great potential for converting many types of plant and animal waste into very high quality animal feed. The availability of an additional natural food source to the free ranging poultry will enhance the system. For organic livestock producers, BSF may provide an inexpensive means to transform a zero-value product, such as eviscerate or plant waste, into a low cost, renewable, organic, high protein feed source. This research will provide valuable data as to the viability of using black soldier flies as a value adding tool in the elimination of organic waste and production of organic feed for free range poultry production.
The objective of the research is to test the effectiveness of BSF as a value adding tool in the production of supplemental organic free range poultry feed. This project seeks to further strengthen the Serengeti Model now in use at White Oak Pastures by filling a gap in the model that currently exists. Because over 60 chicken flocks (containing approximately 500 birds per flock) freely range on 80 acres the need for supplemental feed is a must. This research seeks to document how many pounds of eviscerate (X), with the help of black soldier fly (BSF) larvae, will consistently produce one hundred pounds of poultry feed (Z) in the form of BSF larvae, and how long (Y) it will take to accomplish the transformation: (X + BSF) x Y = Z (100 pounds of feed).
To accomplish this goal black soldier fly larvae will be purchased as well as reared from wild populations in order to maintain a constant and thriving population of captive BSF. Larvae will be regularly monitored for substrate moisture, temperature, consumption of eviscerate waste, maturation times, and general colony health. Mating and oviposition sites will be provided for mature adults and a passive solar heated hoophouse will be constructed for colony maintenance throughout the winter. The Mature larvae will be weighed and a majority will be utilized as poultry feed, while a small proportion will be retained to maintain the BSF adult population.
From May through November of 2012 black soldier flies were successfully reared from the wild population and captive larval populations were maintained in four ProtaPods™ (http://www.thebiopod.com/pages/pages/protapod.html), which were regularly fed waste eviscerate material from the beef processing facility as well as vegetable waste from White Oak Pastures’ organic garden. Larvae were harvested upon maturity, with average yields of 1-2 pounds of mature larvae daily. During the winter months one ProtaPod™ colony was maintained in a small propane-heated greenhouse, where adults were successfully reared from mature larvae throughout the winter. Three colonies were kept outdoors, where they maintained a slower rate of growth and were fed sparingly; these colonies will be used in the coming year to provide an early start to spring and summer BSF production and organic waste conversion. When available, mature larvae were given to two flocks of chickens as supplemental feed.
Impacts and Contributions/Outcomes
Impacts and Contributions/Outcomes:
Since the start of its operation the black soldier fly waste conversion project has provided a new outlet for the disposal of zero-value eviscerate waste, turning organic waste into a valuable and sustainable feed source for free range poultry on the farm. Black soldier flies are beneficial decomposers of a variety of organic materials, do not bite or vector human disease, and have the added benefit of outcompeting pest housefly (Musca domestica) populations where they are present, resulting in more sanitary conditions around humans and livestock. The success of the four trial BSF colonies over the previous year and their ability to survive over the winter in southwest Georgia’s climate makes this insect a promising component of the Serengeti Rotational Grazing Model and a viable contributor to the farm’s organic waste management system when grown on a large scale. In the year to come it is expected that by utilizing previously acquired BSF colonies and creating new colonies from both wild and captive populations, the scale of this operation can be increased to facilitate better usage of organic waste and increased efficiency in waste conversion to an organic poultry feed source.