A study of England’s farmland has found key earthworm types are rare or absent in two out of five fields and has led to the majority of farmers affected vowing to change the way they farm.
The results indicate widespread, historical over-cultivation, and may explain observed declines in other wildlife, such as the song thrush, that feed on these worms.
The #60minworms project was the first comprehensive worm survey concentrating solely on farmland and was carried out by farmers themselves – 57 percent of whom said they would now change their soil management practices as a result.
The scientist behind the survey, Dr Jackie Stroud, a NERC Soil Security Fellow at Rothamsted Research, said:
“Earthworms are sensitive and responsive to soil management which makes them an ideal soil health indicator. The aim of this research was to find a baseline of farmland earthworm populations that would be useful and used by farmers to assess soil health now and in the future.”
Awesome example of citizen science making a difference. The results of Jackie Stroud’s worm survey published today, suggesting huge savings could be made in farmland soil health monitoring.
Read more: https://t.co/M2l5b7eF8t@NFUtweets @Soil_Security @Operation_Earth @wormscience pic.twitter.com/TM5WmAMOOQ
— Rothamsted Research (@Rothamsted) February 21, 2019
Biologists categorise earthworms by ecological role – with surface dwelling and deep burrowing worms the types most sensitive to farming practices, whilst the topsoil worms are generally unaffected by over-cultivation.
Earthworms perform a number of useful ‘ecosystem services’, and high numbers of earthworms have been linked to enhanced plant productivity.
This new citizen science project published today in the journal PLOS One, has revealed most fields have good earthworm biodiversity – meaning an abundance of all three types of earthworms were seen.
In Spring 2018, the average field had 9 earthworms in every spadeful of soil, with top fields having three times that number. One in 10 fields had high earthworm numbers of more than 16 worms per spadeful.
However, the study also revealed that 42 percent of fields had poor earthworm biodiversity – meaning either very few or none of the surface dwelling and deep burrowing worms were seen.