Because earthworms require moist, temperate, dark conditions they cannot cope with extremes of temperature, drying winds and direct sunlight experienced during daytime. Consequently they will be found well below the surface during daylight hours only surfacing at night to feed on dead and decaying matter.
- Some breeds of earthworms never make it to the surface.
- Various breeds of earthworms operate at different depths.
Mature worms seek to avoid active young worms in a crowded bed.
The common experience you observe of worms surfacing during daytime after rain is thought to occur because earthworms are forced from their burrows by rain water which loses its oxygen content as it filters downward leaving little for worms to breath. Contrary to what may appear to be drowned worms on the surface, the earthworms have actually cooked. They die because sunlight can kill them after a couple of hours. The main cause of death is probably exposure to ultra violet light, to which they are very sensitive.
The earthworms ability to breath through its skin absorbing oxygen and expiring carbon dioxide helps it survive in the water for weeks and even months. So although a dry sunlit environment is fatal to earthworms, they can survive in aerated water.
- Eighty five percent of a earthworms body weight is water.
Extreme variations in moisture and temperature levels are probably the major reason for worms disappearing from garden beds over night.
- Earthworms capsules can survive under water and actually hatch.
This can explain the dramatic increase in soil worm populations following drought breaking rains. The dormant capsules are stimulated to hatch by the favourable moist environment.
Tip: Cover worm beds with bags or carpet underlay or commercial worm felt to keep out light and insulate against temperature extremes. Earthworms will then operate near the surface when feed is placed there.
Slime On Earthworms
The mucus that the earthworms excrete through pores in its skin as well, as adding the worms progress, also acts as a waste disposal system of nitrogen laden waste products, and acts as a protective film which prevents toxic material entering the body, but at the same time allows absorption of oxygen.
The nitrogen rich slime lines the earthworms burrows to bind together soil particles. Slime contributes as much nitrogen to the soil as do casts and urine. But this should not be overstated as research is not complete.
The slime often dries silvery to show the earthworms track.
For most households the benefits of growing earthworms can be beneficial,as well as rewarding. In todays climatic conditions , there is more and more emphasis place on recycling and what we can do as individuals to help the environment. Imagine the difference we can make to the environment if even only 1 in 10 house holds used earthworms to recycle our waste.