Invertebrate conservation

Invertebrates are the unsung heroes of our ecosystems — they pollinate plants, recycle nutrients, and form the foundation of food webs.

Yet, many of Mauritius’ unique insects have gone extinct and the remainder are on the brink of extinction due to habitat loss, invasive species, and climate change. For example, of the 125 native and endemic land snail species described for Mauritius, 43 have already gone extinct. Once so abundant in Mauritian forests, snails were collected in buckets to be fed to pigs. Today, endemic snails are incredibly rare due to predation by rats, toads, tenrecs, carnivorous snails, pigs, shrews, habitat loss and now climate change.

At Ebony Forest, together with the National Parks and Conservation Service, we are working to conserve some of Mauritius’ most threatened and poorly known invertebrates as part of our efforts to restore ecosystem functions and save threatened species.

Snail conservation

One of the greatest challenges in conserving endemic snails is simply finding them.

Their numbers are so low and their distribution so fragmented that a day spent searching often ends in disappointment — with few, if any, discoveries, and usually only empty shells. When we do manage to find live individuals, the next hurdle is to understand the conditions they need to survive and reproduce. Without urgent action, we risk a future where more of our endemic snails are extinct than alive.

Some of the snail species we are working to conserve.

Project aim

To captive breed threatened snail species to release into predator-controlled areas to reduce their risk of extinction.

Project impacts

Establishing captive breeding populations of these snails will:

• Expand their distribution
• Increase population size
• Maintain genetic diversity

Additional benefits are:
• Building local conservation capacity
• Raise public awareness of Mauritius’ unique but threatened reptile fauna

Our director’s expertise in snails drives Ebony Forest’s commitment to snail conservation. Discover more by reading our blog post, Meet Mauritius’ Snail Expert: Owen Griffiths or watch the video.

The project began in 2020, when five Pachystyla bicolor were taken into captivity at La Vanille Nature Park.

Since then, more than 850 snails have been bred. Between December 2020 and December 2024, a total of 553 adult snails were translocated from La Vanille and released into two specially designed predator-proof enclosures at Vallée de L’Est, where their population and growth continue to be regularly monitored.

In 2022, the team collected Pachystyla bicolor var. mauritiana to establish a captive breeding colony at Ebony Forest. The specially designed enclosures exclude ants, rats, and other predators, giving the snails the best chance to thrive. To date, over 240 juveniles have been produced, with their growth and breeding monitored monthly.

After months of relentless searching, the team also discovered a pair of the extremely rare Plicadomus sulcatus. From six eggs laid, a single juvenile successfully hatched — a small but significant achievement. Breeding in this species is much slower and more complex than in Pachystyla hence the importance of collecting, monitoring and learning about each species breeding ecology requirements.

As the only organisation in Mauritius actively working on snail conservation, Ebony Forest is helping to fill critical knowledge gaps about these species. Because so little is known about their habitat and breeding requirements, this research is primordial to their survival. By collecting data on breeding, growth rates, diet, and reproduction, Ebony Forest is developing the expertise needed to captive breed and ultimately save these unique endemic snails from extinction.

Pyrgacris relictus, an endemic Mauritian grasshopper, was once known only from a single museum specimen and long thought extinct.

Remarkably, it was rediscovered in 2013 — but it remains Critically Endangered. The extinction of Pyrgacris in Mauritius would mean the loss of the entire family of grasshoppers it belongs to.

Very little is known about this elusive nocturnal species, and few people have ever seen it alive. In an effort to prevent its extinction, Ebony Forest has conducted extensive night surveys in the Black River Gorges National Park to search for individuals and establish a potential captive breeding programme.

The grasshopper depends heavily on Acanthophoenix rubra, a Critically Endangered endemic palm that is also declining in the wild. Despite hundreds of hours of searching, no Pyrgacris grasshoppers have yet been found — a stark reminder of how fragile and irreplaceable our island’s biodiversity is.