An invasive species of worms has been living in Cliff Cave Park.

According to a June 9 social media post by the St. Louis County Parks and Recreation Department, a report regarding a sighting of these worms, called hammerhead worms, was recently received. Hammerhead worms, originally from Asia, are known to harm local ecosystems as they prey on native earthworms and make soil less healthy. 

These worms thrive in heat and humidity and are usually spotted after heavy rains. They typically prefer to hide under logs, rocks and leaf litter. This species has no natural predators — aside from themselves, as they are cannibalistic — due to the toxin they produce. This toxin can irritate the skin upon touch and, if eaten, can make both people and animals sick.

Hammerhead worms are unusually difficult to kill — if cut or squished into pieces, each piece will regenerate into a new worm, adding to the already large invasive population. To safely euthanize a hammerhead worm, the County recommends wearing gloves or using a shovel to place the found worm into a plastic bag, then adding vinegar, rubbing alcohol, salt or soapy water. Once sealed, the bag containing the worm and liquid should be placed in a freezer for 48 hours before being disposed of, still sealed.