The Iberian Lynx Is Doomed — Maybe


The world’s most endangered cat is not the lion or cheetah or tiger; it’s the Iberian lynx. Already at risk for a number of reasons I’ll get into below, a new study from Nature Climate Change predicts that the lynx could be extinct by 2060, driven off the planet by anthropogenic climate change.

As its name suggests, the Iberian lynx belongs on the Spanish-Portuguese peninsula, where it exists in a few isolated places in southwestern Spain and perhaps Portugal (though no one really knows). The IUCN estimates the lynx population at a mere 84 to 143 adult cats; recent counts suggest there may be as many as 250 of these kitties. Even the high number is a pretty small population — thus, the classification as Critically Endangered.

The lynx’s habitat has shrunk from 15,700 square miles in the 1950s to just 460 square miles, estimated in 2005. Like its North American counterpart, the Iberian lynx depends on rabbit for sustenance, but the cats’ bunny meal, the European rabbit, has gone through a major decline because of disease, hunting, and habitat loss. The lynx have also suffered from people trapping and poaching them, and hitting them with cars. (Generally cars and wild cats do not mix well.)

The good news for the lynx is that they have a lot of fans and conservation efforts have been well funded. There have been captive breeding programs, work towards restoring their bunny prey, and other efforts to make the world more friendly to the Iberian lynx, all in the hope that the cat population can grow larger, or at least not die out.

The problem, say researchers in the new study, is that none of these plans account for climate change. When they created a computer model of the lynx and rabbit populations that included the expected alterations to temperature and precipitation, they discovered that the lynx would die out within the next 50 years.

“Our models show that the anticipated climate change will lead to a rapid and dramatic decline of the Iberian lynx and probably eradicate the species within 50 years, in spite of the present-day conservation efforts. The only two populations currently present will not be able to spread out or adapt to the changes in time,” coauthor Miguel Ara├║jo, an ecologist at the University of Copenhagen, said in a statement.

All hope is not lost yet, though. If policymakers incorporate climate change into their plans for the lynx, the cats can survive, the scientists say. If climate change were considered in the planning of reintroduction efforts, those efforts could result in there being as many as 900 Iberian lynx by 2090.

The establishment of wildlife corridors along climate pathways might also help. The research team cautions, however, that the immediate nature of the threat, high costs of the corridor creation, and the fact that translocating lynx is technically feasible means that it’s probably easier to just move the cats rather than try to get them to move on their own through a corridor.

“The risk of extinction faced by Iberian lynx within the next 50 years is high,” the researchers write. But with good planning, extinction of the lynx might still be avoided.


Images Credit: Hector Garrido, CSIC Andalusia Audiovisual Bank, via EurekAlert

The Marsupial Lion Looked Awesome — Too Bad It’s Extinct


Here in the United States, we’re familiar with extinct megafauna like mastodons and mammoths, the saber-toothed tiger and the giant sloth. But the list of huge critters that went extinct long ago is sometimes surprising (there’s the saber-toothed salmon, for example), especially when we look outside North America.

In Australia, for example, there’s the marsupial lion (Thylacoleo carnifex), which lived about 1.6 million to 46,000 years ago. Despite its name and a size that was similar to that of a lion, it was not a cat — it’s more closely related to koalas and wombats — but it was the largest meat-eater ever to live on the continent.

That date for when the marsupial lion died out happens to match pretty closely to when humans first arrived on Australia, and that has led many scientists to wonder whether humans drove the species extinct. But a study released this week by the Proceedings of the National Academy of Sciences says no, that species and other megafauna of the region known as Sahul (which includes Australia and New Guinea) were the victims of climate change, not human hunters.

“It is now increasingly clear that the disappearance of the megafauna of Sahul took place over tens, if not hundreds, of millennia under the influence of inexorable, albeit erratic, climatic deterioration,” the study’s lead author, Stephen Wroe of the University of New South Wales, said in a statement.

It’s too bad that the marsupial lion was lost, because it appears that it would have been a pretty awesome animal: It had semi-opposable thumbs, for instance, which may have helped with holding prey. But I probably wouldn’t have wanted to meet one out in the wild.

Artwork by Peter Schouten, via EurekAlert

Long Before Europeans, Pacific Island Birds Went The Way Of the Dodo

574px-Chelychelychen_quassusThe extinction of the dodo is so well known, it became an idiom. But to recap: The large flightless bird was discovered on Mauritius in 1598 as the Dutch were settling the Indian Ocean island. By 1662, the bird was extinct, wiped out by humans and the animals they brought with them who found the dodo tasty and easy to catch.

It might be easy to think that such a phenomenon is a modern one, that as Europeans branched out and settled the world, they brought death and destruction to the lands they conquered. But it wasn’t just Europeans, as a study published today by PNAS shows.

The goal of the study, led by the University of Canberra in Australia, was to estimate the number of bird species that went extinct as humans colonized remote islands in the South Pacific. These islands were some of the last places in the world to become inhabited — ranging from New Caledonia and Fiji, settled some 3,500 years ago, to Hawaii, around 700 to 900 years ago. And as with the dodo, when humans arrived, birds disappeared.

Determining how many bird species the islands once had, though, is rather difficult. Fossils are scarce for a lot of the islands. And differences in islands and species make generalizations from one island to the next complicated. The researchers got around this by employing a common technique from ecological studies: mark and recapture. The species that were on an island when Europeans arrived were the “marked” individuals and the fossil species were those that were “recaptured.” With those numbers, the scientists could extrapolate how many species had once existed on an island. And from the 41 islands they studied, they could extrapolate further to the group of 269 remote Pacific islands.

The research focused on nonpasserine land birds, which are better documented in the fossil record. The researchers estimated that about 1,000 species of these birds went extinct after humans arrived on these islands but before Europeans showed up. That’s around two-thirds of the distinct species that once inhabited those islands.

Most vulnerable were, not surprisingly, flightless birds and larger species, those that would have made for the easiest and best meals.

And the fewer islands on which a species could be found, the more likely it was go extinct; those that were endemic to a single island were among the most likely to disappear.

Smaller islands and those with less rainfall were also more likely to see extinctions. “Islands with lower annual rainfall were more extensively deforested in the period between first human and European arrival,” the authors write, “suggesting that higher rates of extinction were associated with greater loss of forest habitat in lower-rainfall areas.”

New Zealand was not included in the study, but the researchers say that its “large size, rugged landscape, and high rainfall sets it apart” from other Pacific islands, with the result that some large flightless birds, like the kiwi, have managed to survive.

That humans have been driving species to extinction for a long time is not really a shocker, though. Hunting, habitat destruction, the introduction of invasive species — these are not modern inventions, and neither are their results.

Image of moa-nalo by Stanton F. Fink, via wikimedia commons