A viable technique for tagging earthworms using visible implant elastomer

Earthworms perform many ecosystem services. However, due to their body shape, mucus covering, and subterranean behaviour, it has been very difficult to successfully tag individual animals for experimental purposes. This paper examines the potential use of commercially available visible implant elastomer (VIE) tags to mark earthworms. Two laboratory experiments were conducted employing four temperate earthworm species by injection of the VIE and making regular assessments. Results showed that the biologically compatible polymer tags, injected into earthworm muscle, remained in the animal and could be visually located after a period of 12 months. Tagging did not affect growth to maturity, mating or cocoon production of Lumbricus terrestris. VIE tagging can now be viewed as a viable technique for marking this and other earthworm species.