Written by: Dr. Jacquie Jacob, University of Kentucky
A properly designed and operated composter can break down bird carcasses and produce a useful soil amendment for your garden. Many industrial-scale poultry operations use large composters for disposal of carcasses. Minicomposters are available that make it possible to compost a few dead birds in the backyard.
Composting dead birds involves the same biological processes that occur when composting other organic material. The organic matter is broken down by bacteria, fungi, and other microorganisms.
Composting involves providing microorganisms with the environment that is best suited for their growth. The right balance of air, water, nitrogen, and carbon in compost will produce heat to kill any pathogens present. Dead birds supply the needed nitrogen. Carbon materials such as sawdust, straw, paper, cornstalks, and other bulky, fibrous material must be provided. The art of composting involves managing the amount of moisture. Too little moisture, and the tissues of dead birds dehydrate, making them difficult to break down. Too much moisture, and compost begins to smell. The moisture content should be 40% to 50% of the total content of the compost. To determine whether compost has the appropriate level of moisture, squeeze a handful of compost mix. The amount of moisture is correct if the compost leaves wetness on the palm of your hand but does not form drops.
Minicomposters can range from simple boxes made of wood to commercially available plastic tubs. Minicomposters should be big enough to retain all the heat produced during decomposition. The minimum dimensions recommended for a box design are 36 in. high by 40 in. wide. When beginning a batch of compost in an empty composter, it is necessary to layer different composting materials so that the optimum composting temperature of 140°F is reached before the dead birds are placed in the bin. A compost thermometer is necessary to determine when the bin is ready for loading and to make sure that the proper temperature is maintained during the composting process.
A common recipe when starting compost is to use two parts poultry litter to one part straw. The materials should be placed in layers until the base is 6 inches deep, with moisture adjusted as the layers are being added. The dead birds should be placed in the center of the compost, with a minimum of 6 inches of insulating compost cover on all sides, as well as above and below the birds.
Composting should be complete seven days from the addition of the last carcasses. The contents of the composter can be used as a soil amendment for gardens. When a batch of compost is complete, the composter can be emptied and a new batch started (as per the instructions above), or one-third to one-half of the contents can be left in the composter for the start of a new compost cycle.
Composting animal mortalities on the farm. Herbert Brodie and Lewis Carr, University of Maryland.