10 a.m. to 4 p.m. Schedule
In the rotunda of the Wildlife Interpretive Gallery stands an exhibit devoted to the Partula nodosa snail – a unique effort that highlights the Detroit Zoological Society’s commitment to conserving even the tiniest of creatures.
Partulid snails like the P. nodosa were once found across Tahiti and other south Pacific islands in an array of more than 125 different species. These striped snails were used in ceremonial jewelry and decorations of indigenous islanders, and the snails served as a study group for scientists to learn more about the evolution of diversity.
Much of the Partulid snail diversity was lost due a botched attempt at “biological control”, or the control of a pest by the introduction of a natural enemy or predator. In 1967, giant African land snails were introduced to Tahiti and other south Pacific islands to serve as a source of protein for local residents. Some of the African snails escaped, bred very rapidly, and began eating farmers’ crops, threatening the local economy. To control the African snails, Florida rosy wolf snails were introduced a decade later, but the wolf snails preferred to eat the Partulid snails, which caused the extinction of many of the Partulid species.
Since 1989, the DZS has been breeding P. nodosa snails as part of a collaborative effort credited with saving the species from extinction. The work began with 115 snails of five species, with the DZS concentrating its efforts on this one species and engaging other institutions to focus on the remaining four.
At one point, all the P. nodosa in the world lived at the Detroit Zoo. The DZS’s successful breeding of the snails has resulted in the rescue and recovery of the species. Currently there are around 6,000 individuals living in North American zoos, all descendants from the Detroit Zoo’s original small group.
One hundred Partula nodosa snails bred at the Detroit Zoo were released in Tahiti in the summer of 2015, and another 60 snails were released in 2016. In 2018, an additional 80 snails were sent to the Netherlands for eventual release to Tahiti – effectively restoring a population that was extinct in the wild. The DZS maintains a colony of Partula nodosa in a carefully controlled environment for future releases.
With the sufficient growth of the captive population and the establishment of a protected area on Tahiti, this species is officially on the road to being saved!