Complex sentence: Snails were no longer present at Upper Hot, Upper Middle, Kidney, and Vermilion Cool springs and are now present at Upper middle and Kidney due to Parks Canada's Recovery actions in 2002 for the Upper Middle and 2003 for the Kidney spring.
Split into simpler sentences: Snails were no longer present at Upper Hot, Upper Middle, Kidney, and Vermilion Cool springs. However, they are now present at the Upper middle and Kidney due to Parks Canada's Recovery actions in 2002 for the Upper Middle and 2003 for the Kidney spring.