Invertebrates
Rosy Wolf Snail
Euglandina rosea · also called cannibal snail
Following the glistening slime trail of another snail across a forest floor, a rosy wolf snail closes in on its prey, a hunting strategy that, after deliberate introduction to control a pest species, instead drove numerous native Pacific island snails to extinction.
Overview
The rosy wolf snail, Euglandina rosea, is native to the southeastern United States but has been introduced and established on islands worldwide. Its slime-trail hunting strategy, disastrous history as a failed biological control agent, and status as a cautionary tale in conservation biology make it one of the most ecologically significant invertebrates ever deliberately introduced by humans.
A predator that solved the wrong problem
Introduced to hunt the invasive giant African land snail, the rosy wolf snail instead turned its slime-trail tracking skills on native island snail species that had no natural defence against it, a mismatch between intention and outcome that reshaped how scientists think about biological control.
Status
Least Concern, remaining widespread and secure both in its native southeastern United States range and in the many island regions where it has become established.
Rosy Wolf Snail: common questions
How does the rosy wolf snail find its prey?
It follows the slime trails left behind by other snails and slugs, tracking them down using this scent-like trail before catching and eating them.
Why was the rosy wolf snail introduced to Pacific islands?
It was deliberately introduced in an attempt to control the invasive giant African land snail, a significant agricultural pest, by giving it a natural predator.
Did introducing the rosy wolf snail work as planned?
No, the introduction backfired badly; rather than controlling the giant African land snail effectively, the rosy wolf snail instead hunted down and drove numerous native island snail species to extinction or near-extinction.
Why is the rosy wolf snail used as an example in conservation biology?
It is frequently cited as a textbook cautionary tale about the risks of introducing one species to control another, since the consequences for native wildlife can be severe and difficult to reverse once the predator is established.