A method and device are provided for transferring heat from decomposing manure to a worm growth zone. A shelter contains manure in a first area and a worm growth bed in a second area. The worm growth bed supports a plurality of worms substantively covered by a layer of manure. Vermicast passes through a supporting grid of the worm growth bed and deposits on a floor or a bottom of the second area. Heat generated by the manure is transferred to the worm growth bed by radiant heat transfer and/or by air convection. The manure is transferred portion by portion over time from the first area to the worm growth bed. The shelter may include a battery, a solar power converter, a microcontroller, dynamic memory, a real-time clock, a wireless transponder, temperature sensors, humidity sensors, water pumps, and/or springs or motors used to open or close apertures of walls of the shelter.