More than a decade ago, conservationists began working to preserve a unique population of desert pampas cats that has adapted to the mangroves of Peru’s northern coast. This small, isolated population roams the San Pedro de Vice dry mangroves, a Ramsar Site and South America’s southernmost mangrove ecosystem.

“This is a very unique population, because as far as we know, [it] is the only Pampas cat population that lives in a mangrove [habitat],” Alvaro Garcia, co-coordinator of the Pampas Cat Working Group and the Peruvian Desert Cat Project, told Mongabay in an email.

The desert pampas cat (Leopardus garleppi), distinctive for its broad face, ranges along a relatively thin band snaking southward from Colombia through Peru and Bolivia, to northern Chile and Argentina. The species is acclimated to dry conditions, so inhabits deserts, grasslands and dry forests, and isn’t found living in mangroves anywhere else aside from this region of Peru. Dry mangrove forests, also called scrub or dwarf mangrove forests, grow in highly saline soils in upper intertidal zones, so lack regular daily flushing by ocean tides.

At first, it was thought the dry mangrove-acclimated cats were faring well: “[I]n the mangrove [habitat], we put cameras out for a week, and we got tons of photos,” whereas in other parts of the felid’s range, conservationists barely capture one desert pampas cat image per month, said Cindy Hurtado, co-coordinator of the Pampas Cat Working Group and the Peruvian Desert Cat Project.

Based on the photos, the research team assumed the San Pedro de Vice population was stable, and considered focusing their conservation attention elsewhere. But instead they decided to take advantage of the presence of pampas cat latrines in the dry mangrove habitat to run a genetic study. (Finding sufficient cat feces for this kind of noninvasive study was easy there, but is generally a real challenge elsewhere, Hurtado said.)

That genetic study turned their “safe population” assumption on its head.

What they found is that in fact the dry mangrove population is in a perilous state; the habitat hosts just nine individual cats, all related. Also troubling is the effective population size, a measure of how many cats are actively breeding: only around two in this case.

“That’s a big concern, because in a small population, the most important thing is not how many individuals we have, but how many are moving genes to the next generation,” said Manuel Santiago, first author on the paper, who is with the University of Idaho in the United States.

The genetic findings took the team by surprise. “Initially we were thinking that this was a healthy population,” Garcia said. “But the genetic diversity is very low and there is a [genetic] bottleneck” that threatens local extinction.

The problem: Over time, the genetic diversity of this population will likely dwindle further, and the population could be lost completely. That, the conservationists say, would mean losing these unique mangrove-adapted desert pampas cats. That loss could have repercussions for the wider ecosystem as well as potential human health impacts.

The researchers warn that a local extinction of the rodent-hunting pampas cat would result in an overpopulation in the dry mangrove habitat of the house mouse (Mus musculus), a nonnative species, which is already abundant in the San Pedro de Vice area. The invasive house mouse is outcompeting a native rodent, the Peruvian leaf-eared mouse (Phyllotis gerbillus), and is pushing it to the verge of local extinction.

Uncontrolled growth of the rodent population could increase disease risk for other wildlife, Garcia said, as well as for people who use the area for fishing and recreation. One concern is a potential increased transmission risk of leptospirosis, a bacterial disease carried by rodents that can be fatal and has caused deaths in Peru.

“I think we will be facing an overpopulation of rodents, that in the end, could damage the entire ecosystem,” Garcia said. “These [mangrove] wetlands are also rare in the area,” so are worth conserving.

Next steps

The researchers say there are only a few options to ensure the persistence of the mangrove specialist cats, including protecting their habitat and maintaining their prey base. Beyond that, the easiest solution, in theory, would be to translocate pampas cats from other areas into the mangrove habitat. But translocation is rife with difficulties, starting with getting permits for such a project, Hurtado said. Also, taking a desert- or Andean-adapted pampas cat and dropping it into a mangrove ecosystem seems unlikely to succeed.

Currently, the team is investigating a nearby pampas cat population that lives farther south in Peru and also dwells in a mangrove forest, and another to the east, which lives in a wetland. To date, there’s limited data on the size of these populations and whether they’re genetically healthy. To fill this knowledge gap, the researchers hope to replicate their genetic study in both locations.

But those studies depend on finding sufficient felid feces. The team plans to use working dogs to help them locate hard-to-find cat scats.

“We are looking to see which of these areas has better genetic diversity to target the creation of a wildlife corridor,” Garcia said, adding that designing such a link would be a lengthy process that hinges on engagement with local authorities and sufficient funding.

“It’s better to [translocate] cats from closer populations or try to make the cats go to the mangrove by increasing connectivity,” Garcia said.

No matter what conservation approach the researchers settle on, the chances of success are limited. The dilemma faced by the dry mangrove-adapted pampas cat also offer a warning for other small wildcat species globally that face similar pressures, especially habitat fragmentation and isolation, coupled with other pressures.

A risk of genetic bottlenecks and local extinctions

“Even though we are photographing cats, we don’t actually know if populations are healthy or not, because their genetic diversity could be low,” Garcia said. “This might be a big problem that we are ignoring elsewhere.”

While the pampas cat is categorized on the IUCN Red List as near threatened, it’s proposed seven subspecies, and their various local populations, could face widely varying degrees of genetic endangerment, which could go undetected without genetic studies.

Complicating its threat status further, researchers have suggested recognizing five separate pampas cat species, with no subspecies. Hurtado, for example, said that if the desert pampas cat is recognized as an individual species, it may warrant vulnerable IUCN status based on available data.

Elsewhere in South America, the endangered Andean cat (Leopardus jacobita) and Chile’s endemic guiña (Leopardus guigna), are among isolated felid species populations that also give cause for possible genetic concern. Raíssa Sepulvida, a biologist and field technician with Panthera, the international wildcat conservation NGO, notes that other species, including ocelots (Leopardus pardalis) and margays (Leopardus wiedii), face genetic isolation in Brazil’s highly fragmented Atlantic Forest.

A major challenge to doing genetic research on these cats centers around obtaining sufficient material (such as feces) for analysis, and also the high cost of such research. As a result, “We don’t have that many projects that are looking at the genetic diversity of these species,” Sepulvida said, meaning that conservationists could be blindsided by genetic bottlenecks and local extinctions.

A pampas cat pawprint. The species can have a home range of about 14 square kilometers (5.4 square miles), but in the San Pedro de Vice dry mangrove habitat the cat’s range can be as small as 3 km2 (1.16 mi2). Image courtesy of the Peruvian Desert Cat Project.

For Sepulvida, the pampas cat mangrove study underlines the need for researchers to think bigger, and push for conservation at a wider landscape scale to conserve wildlife in general, and small cats in particular. These felid species “cannot displace over longer distances. So they are more at risk of this kind of situation,” she said.

“Sometimes we think if you have an isolated, very preserved area, we can preserve the species,” she added, but “you need to have larger areas that can maintain multiple populations of these species” in order to preserve genetic diversity.

The surprising San Pedro de Vice mangrove pampas cat habitat findings are spurring biologists to assess genetic diversity in other pampas cat populations, Hurtado added. “We think this study is a warning sign, because the Pampas Cat Working Group has around 16 projects across South America and none of us are [currently] looking at genetics.”

Banner image:A desert pampas cat (Leopardus garleppi). A genetic study caused researchers to raise an alarm over a small, unique, dry mangrove-adapted population being genetically unhealthy, putting it at risk for local extinction. Image courtesy of the Peruvian Desert Cat Project.

This article originally published at Mongabay.com