“Re:wild: The Search for Lost Species” sounds like the title of an action-adventure movie, and in a way, this ambitious and optimistic initiative contains all of the plot lines to keep us nature lovers on the edge of our seats. The endeavor has scientists around the world looking for plants, animals and fungi that have been lost to science for at least 10 years, and sometimes even hundreds of years.

To help focus their attention and energy, Re:wild (an organization founded by a group of conservation scientists together with actor and activist Leonardo DiCaprio) compiled a “Most Wanted” list—a subset of 25 of the more than 2,200 lost species across 160 countries.

What does it take for a species to make this list? Making things a bit confusing, there is no international standard that defines what constitutes a “lost” species, nor a rediscovery. Adding to that, the criteria varies by taxa. Because of this, in 2017 (and every year since), Re:wild has relied on experts from more than 100 IUCN Species Survival Commission specialist groups to nominate species that they consider lost.

At minimum, a species has to have been unseen by scientists for at least a 10 years and cannot be found anywhere in captivity. Currently, the Re:wild Most Wanted list includes 10 mammals, four birds, four fishes, two amphibians, one coral, one tree species, one arachnid, one fungus and one reptile. The species represent ecosystems in at least 17 countries.

How Do Species Get Lost?

Species become lost for a variety of reasons. In some cases, species that once existed in healthy populations are now potentially extinct due to habitat loss, disease, introduction of invasive species, poaching and human-wildlife conflict. In other cases, scientists simply haven’t had direct access to the species because they are only found in dense wilderness areas or in conflict-ridden regions. If a species was pretty rare to begin with, a single disturbance can be all it takes to wipe out the entire population.

And for something on the list to be considered found again? Unfortunately, sometimes lost species show up in marketplaces that sell animal parts, but that isn’t enough to consider taking them off the list. Rediscovery of a species is only considered confirmed if scientists, naturalists or other experts have verified that it is still alive in its wild habitat. Approved evidence can be in the form of photo and video, or a photograph verified by DNA or eDNA from the rediscovery site. (eDNA—or environmental DNA—is DNA that is released from an organism into the environment and subsequently collected from environmental samples such as soil, seawater, snow or air, rather than directly from the body of an individual organism.)

Lost Species Rediscovered!

In amazing news, just since 2017, Team Re:wild has found a whopping eight of its 25 most wanted lost species! The species that had been rediscovered are the Jackson’s climbing salamander in Guatemala, Wallace’s giant bee in Indonesia, velvet pitcher plant in Indonesia, silver-backed chevrotain in Vietnam, Somali sengi (or elephant shrew) in Djibouti, Fernandina Galapagos tortoise in the Galapagos Islands, Sierra Leone crab in Sierra Leone and Voeltzkow’s chameleon in Madagascar.

Somali Sengi

The Somali sengi was rediscovered in 2020 after being lost for more than 50 years.

And those are in addition to other lost species that have been rediscovered, such as the longnose harlequin toad, which was just listed as critically endangered last month after being rediscovered in Ecuador in 2016, and the northern Haiti magnolia, which an expedition team found this June after it was lost to science for nearly 100 years!

There is no such thing as resting on these laurels, though. Once these were officially found, eight more species were immediately added to the Most Wanted list. 

This type of success doesn’t just happen—it really is a team effort. Scientists often conduct local interviews, then, based on that information, they head out on searches. During their exploration, they often place camera traps for consistent monitoring of the habitat. They also try to collect eDNA; the more information that can be gathered, the higher the success rate of actually finding a previously lost species.  

On these expeditions, scientists try to learn as much as they can about the habitats these species once called home, and efforts are made to try to find or create conservation opportunities. No one goes into the field expecting to find a species on the first try—sometimes it takes years of concentrated effort to glean even the tiniest hint that the species may still be around.

But what happens when a species is actually found? In those cases, Re:wild goes straight to local and international partners to urgently catalyze quick conservation action for the species. This could manifest in many ways: their on-the-ground local partners could start to work with the regional community to educate people on the importance of protecting the newly found species, or it could mean establishing a protected area and working with local governments to enact strict protection laws. The conservation strategy implemented depends on the natural history of the species, its habitat and the specific threats that caused it harm in the first place (and of course new threats that may likely appear in the future). 

For example, after the exciting rediscovery of the Jackson’s Climbing salamander in Guatemala, Re:wild ran a successful fundraising campaign fueled by the enthusiasm generated from the rediscovery to expand the reserve where the salamander was found. This ensured that its cloud forest habitat is and will stay safeguarded. When the silver-backed chevrotain was rediscovered, Re:wild partners were able to find two other populations of the lost species! They now have the resources study how large and stable these populations are get a better idea of the threats to their survival. 

How Ecotourism Can Help Save Lost Species

Support for lost species comes in many ways. Even taking a trip with us at Nat Hab helps rewilding efforts. Although you probably won’t be the one to find a lost species on an adventure with us, conservation travel to certain countries where recently found species live or where lost species are thought to be helps protect those habitats.

On our The Wilds of Borneo: Orangutans & Beyond trip, your travel supports the ecosystem where the velvet pitcher plant was just found. While there, you can also go behind the scenes at the Bornean Sun Bear Conservation Centre to learn how the world’s smallest bear was brought back from the verge of extinction not so long ago.

Sun Bear in Borneo by Brad Josephs

Sun Bear © Brad Josephs

Joining our Madagascar Wildlife Adventure offers up some much-needed assistance for the habitat of the Voeltzkow’s chameleon. Ecotourism in Madagascar is a work in progress, and it’s a sad but true fact that without eco-conscious travel, most of Madagascar’s remaining wild habitat would be gone. Enthusiastic visitors who come to observe the intriguing species found in Madagascar’s biodiverse forests signal to local communities the value of protecting their ecosystem.

On both our Classic Galapagos and Galapagos Hiking & Kayaking Adventure trips, you can do your part through responsible ecotourism to help draw awareness to the remarkable Fernandina Galapagos tortoise. 

All is not lost. Through optimism, concerted effort, community and global support, and conscientious, responsible tourism, we can all do our part to help rediscover many of the more than 2,200 lost species that the experts at Re:wild are pouring their hearts and souls into finding.