Black soldier flies as a sustainable feed alternative for aquaculture
Our project explored the feasibility of using black soldier fly larvae (BSFL) as a supplemental feed source for tilapia. Black soldier flies were raised inside a heated greenhouse and outside in a large compost bin, and fed food waste year round. In 2014 we found it was not an efficient use of space to raise BSFL inside the greenhouse. The project was moved outside where the insects developed a large colony in an outdoor compost bin very quickly.
In Winter 2013/2014 we focused mainly on ways to sustain a reproducing colony inside a heated greenhouse during cold upstate NY weather. The goal was to both keep the larvae alive, as well as develop into flies to lay viable eggs.
During 2014 growing season we aimed to raise larvae outside in an enclosed compost pile and use ramps to have the larvae self-harvest.
We found that the colony grew expectionally quickly in an open air compost bin. Food waste and other green compost material from the farm site was added to this compost bin, layered with brown material (dried leaves and wood chips). We found the compost bin with black soldier fly larvae decomposed the compost faster than compost with only worms.
Larvae in the outdoor compost bin consumed more than anticipated quantity of food waste. The large open outdoor system allowed BSF population to expand quickly. An unexpected outcome of the research found the compost pile with BSFL decomposed much faster than the pile with only earthworms. It was especially useful for composting unwanted fish because they were consumed by the larvae before unpleasant odors or pests problems developed in our urban setting.
Using one large outdoor system was preferable to multiple small indoor systems during summer months because greenhouse space is limited by growing practices. At this stage in the insect raising process it is not as cost effective to use the greenhouse space for BSF as it is for other plant production. The outdoor system worked as a great alternative. However, we still need to experiment with new ways to extract the larvae in higher quantities from outdoor compost systems.
We found the larvae pupated into adults inside the containers instead of the intended breeding cage, flew around the greenhouse and outside, mated, and laid eggs back into the containers thus increasing the population regularly during warm weather and longer days, April to October. Unassisted reproduction decreases workload for individuals raising BSFL. The trade-off is less control of the number of larvae reproducing and the number used as fish feed.
Impacts and Contributions/Outcomes
Main Street Farms, LLC
116 North West Street
Homer, NY 13077
Office Phone: 6077450419
Vice Provost of Research and Director of McIntire-Stennis Forestry Research
200 Bray Hall
1 Forestry Drive
Syracuse , NY 13210
Office Phone: 3154706606