Earthworms - Winter Wildlife

Earthworms - Winter Wildlife

Earthworms are not actually a type of scientific classification but instead is the common name used to describe the largest members of Oligochaeta which are found in the phylum Analidia. Currently there are 29 species of earthworms in the UK that are considered native. And they are typically split into 3 ecological groups Epigeic, Endogeic and Anecic although some people also consider compost worms to be an extra ecological group. 

Epigeic 

Epigeic earthworms typically live on the surface of the soil in leaf litter as they are not great at making burrows. Because they are not adapted to create burrows, they usually live in and feed on the leaf litter. Epigeic earthworms can be found in practically all corners of the world and are necessary in converting leaflitter or any other debris into new fertile topsoil’s. Epigeic earthworms are also often bright red or Reddy-brown, but they are not stripy. 

Compost worms 

Compost worms are usually found in compost heaps or areas filled with rich rotting vegetation like mushrooms. They like to be in warm and moist environments with a constant supply of compost. Compost worms eat through these solids quickly and usually reproduce very fast. These worms are usually bright red in colouring with a clear stripy pattern along their entire body. They are also used to help with waste disposal as they can get rid of many contaminants found in soils. It is worth noting however that compost worms themselves are technically not a category themselves but a part of Epigeic worms. 

Endogeic 

Endogeic earthworms live in and feed on the soil. They make horizontal burrows through the soil to move around and to feed and they can sometimes be seen reusing these burrows. Endogeic earthworms are normally pale in colour like grey, pale pink, green or blue. Some can burrow very deeply in the soil. 

Anecic 

Anecic earthworms make permanent vertical burrows in soil. They mainly feed on leaves on the soil surface that they drag into their burrows but can also feed on soils when making their burrows. They can also sometimes be seen creating casts on the top of soils these casts can often be seen in open fields or grasslands.  Some Anecic earthworm species also make middens (piles of casts) around the entrance to their burrows. Anecic species are the largest species of earthworms in the UK. They are darkly coloured at the head end (red or brown) and have paler tails. 

Ecological role 

Worms also play a crucial role in the ecosystem as they provide a variety of benefits to soils. Although the different ecological grouping provides different benefits. Firstly, worms can recycle waste by breaking up organic matter like leaflitter and integrating it into the soil this process can also help regulate the amount of nutrients in the soil which supports the growth of healthy plants. Worms also help regulate water flow as the burrows they make allow for water to soak up in the soil decreasing surface runoff which often removes the fertile topsoil of habitats and increases the risk of flooding. Furthermore, as they allow more water to be taken up in the soil it also allows for more water dependent plants to grow. Lastly worms also help in aerating the soil this allows more beneficial bacteria to grow in the soil while also allowing some species of microorganisms to thrive in the soil. Aerating the soil is also beneficial as this allows a larger variety of plants like grasses to grow and gives more room for the roots of plants to develop this in turn increases the overall diversity of plant life in the ecosystem.  

worms in a wormery
worm holding
Author
Rafael Fernandes