It\u2019s been 22 years since someone last photographed the \u201cAsian unicorn\u201d. Also known as a saola, it was last seen via a camera trap in Qu\u1ea3ng Nam province, Vietnam, but nobody\u2019s seen one since.<\/p>\n
Proving an absence of something isn\u2019t easy, especially when dealing with elusive animals that occupy remote habitats. So, how do we know when a species is extinct<\/a>? It takes time, which is why some are hopeful that out there somewhere, saolas still roam the forest.<\/p>\n For Pseudoryx nghetinhensis<\/a>, as the animal is known to science, the most optimistic estimates say there could be around 100 left in the wild. Others fear it could already be extinct, but they haven\u2019t given up.<\/p>\n “Right now, the existence of live saolas can neither be proven nor disproven,\u201d said Nguyen Quoc Dung from the Forest Inventory and Planning Institute in Vietnam in a release<\/a>. \u201cThe last evidence we have was from 2013, when one was captured on a camera trap. But given the remoteness of its habitat, it is extremely difficult to say for sure whether there are still a few out there. There are some signs and indications that still give us hope.\u201d<\/p>\n \u00a0<\/p>\n A recent paper discovered that saolas are actually split into two populations that exhibit considerable genetic differences. That split happened around 5,000 to 20,000 years ago, and it offers us an opportunity: if we could mix the populations back together again, we might just be able to restore some of the genetic diversity that\u2019s been lost as their numbers have plummeted.<\/p>\n \u201cIf we can bring together at least a dozen saolas \u2013 ideally a mix from both populations \u2013 to form the foundation of a future population, our models show the species would have a decent chance of long-term survival,\u201d said Rasmus Heller, senior author of the study and Associate Professor from the Department of Biology at the University of Copenhagen. \u201cBut it hinges on actually locating some individuals and starting a breeding program. That has worked before when species were on the brink of extinction<\/a>.\u201d<\/p>\n So, the hunt is on to find 12 saolas, but how do you find a species scientists have been looking for (largely unsuccessfully) since the 1990s? One place you can turn to is leeches.<\/p>\n Yes, leeches. Those blood-sucking invertebrates you sometimes find after a nice swim in a pond. Leeches, as well as the general environment, can be a treasure trove of environmental DNA, something we\u2019re increasingly using in conservation research.<\/p>\n