Extinction Blog

Could selective breeding recreate an extinct tortoise?

A century or so of careful breeding could bring an extinct Galapagos tortoise species back from the dead, scientists said this week.

Of the 15 giant tortoise sub-species found by Charles Darwin on the Galapagos Islands in the 19th Century, four have since gone extinct. But researchers from Yale University suggest that the genetic markers from one extinct sub-species -- the Charles Island Tortoise (Geochelone elephantopus galapagoensis) -- can be found in some of its surviving cousins. They say that selectively breeding and hybridizing these cousins could, eventually, recreate the once-extinct sub-species.

It won't be easy, and it won't be quick. The hybridization would take at least 3 or 4 generations, with 25 years between each generation.

But even with this time frame, the team from Yale is definitely excited to get started. Later this year they will start an "exhaustive survey" of tortoises on nearby islands to find enough to match the genetic makeup of the Charles Island Tortoise. Then the real work begins.

Obviously, this won't work for any extinct species, only sub-species that are close enough genetically to interbreed. But this research reminds us that history is a living thing, and that hope exists for even the species we have lost.

Let's wish the team -- and the tortoises -- luck, even though none of us reading about this will be around long enough to see how the whole experiment works out.

Could global warming benefit one species of endangered shark?

Australia's grey nurse shark could go extinct by 2050 if its populations keep dropping at current levels -- unless something unexpected saves them. Say, global warming for example.

Yes, global warming. A group of scientists this week offered up the possibility that global warming could actually keep the grey nurse shark from going extinct in Australia.

It seems that the grey nurse shark is too sensitive to cold waters to migrate all the way around Australia. This has kept the continent's two populations of grey nurses separated for 100,000 years. But if climate change makes the waters around Australia warmer, the two populations could finally meet and start breeding, a shot in the arm for the critically endangered species.

Of course, the potential to save one species isn't exactly worth the cost of global warming, and the University of Adelaide's Associate Professor Corey Bradshaw says "This is probably one of those one in a hundred examples where climate change may actually be somewhat beneficial for this particular species."

Of course, even if the shark does benefit from global warming, it will still face its existing threat: commercial fishing, which kills millions of sharks a year worldwide.

It's also worth noting that the grey nurse shark (Carcharias taurus) exists elsewhere in the world, where it is often known by different names. The entire species is listed as "vulnerable to extinction" by the IUCN Red List. The species is worst off in Australia, where it is considered "critically endangered."

State of the world's birds: It ain't good

Even the world's most common bird species are disappearing, according to a new study from BirdLife International.

The study's findings are bleak. In Europe, 45% of once-common birds are in decline. In Australia, 81% of wading birds have seen population drops. In North America, 20 different common species have lost half of their populations. And as we've written before, more than 99% of India's vultures have disappeared.

All told, BirdLife has identified 1,226 bird species (1 in 8) as threatened, and 190 facing imminent risk of extinction.

BirdLife released their study, State of the World's Birds, and its accompanying website at their world conference today in Buenos Aires.

"Many of these birds have been a familiar part of our everyday lives, and people who would not necessarily have noticed other environmental indicators have seen their numbers slipping away, and are wondering why," said Dr. Mike Rands, BirdLife's CEO. "Because birds are found almost everywhere on earth, they can act as our eyes and ears, and what they are telling us is that the deterioration in biodiversity and the environment is accelerating, not slowing."

Threats to bird species include the usual suspects: habitat loss, pollution, invasive species and diseases, and climate change. Every single one of these threats can be traced back to human activities.

So what can we do to reverse this rapid decline before it gets too late? BirdLife says that government action is necessary (Rands estimates it would cost just $1 billion a year to preserve all of Africa's biodiversity). They also recommend greater efforts to establish key conservation areas on land and sea and linking biodiversity conservation to peoples' livelihoods around the world.

A win for wolves!

Wolves may not lose their endangered species status after all. The good news came in yesterday as the U.S. Fish and Wildlife Service announced it plans to withdraw its March ruling that wolves had fully recovered in the Northern Rockies.

The original ruling produced an instant wave of reactions around the country. Conservationists damned it, while the states of Montana, Idaho and Wyoming started preparing for wolf hunts this fall.

This withdrawal isn't a done deal. The Department of Justice still needs to sign off on it, as does U.S. District Judge Donald Molloy, who has been presiding over a lawsuit by conservation groups to keep the wolves protected.

Molloy issued a temporary injunction against wolf hunts in June while the lawsuits were underway.

Could this be a rare win for wildlife? One can only hope.

P.S. -- Hmmm... I wonder how Sarah Palin feels about all of this?

Africa's bushmeat problem

It's a catch-22: you eat protein or you die. If you're hungry, that often means eating animals, no matter what species they are or where you get it.

In central Africa, protein is so rare that 80% of locals depend on bushmeat -- wild game, basically -- as their sole source of fat and protein. But a new report from the Center for International Forestry Research (CIFOR) estimates that central Africa "harvests" one million metric tons of bushmeat every year, and that could wipe out many rare and endangered species within decades.

Some have called for a complete ban on the bushmeat trade as a way of eliminating the illegal trade in endangered species. But CIFOR has cautioned that a blanket ban would, in fact, doom the humans who rely upon bushmeat. Instead, CIFOR recommends protecting certain species -- such as gorillas and elephants -- while leaving other species like deer and rodents open for exploitation as food sources.

Why is bushmeat so important to these areas? Many residents of central Africa live in extremely remote villages. Roads aren't paved, vehicles are rare, and gasoline to power vehicles is even rarer. Inter-village trade is done by foot or bicycle, with travel taking days in each direction. This is hardly an ideal situation for commercial farming, so people do what they have to do to eat

I recently attended a lecture by Ingrid Schulze, a volunteer with a sister city partnership between Falls Church, Virginia, and Kokolopori, Democratic Republic of Congo. The partnership recently built a health clinic in remote Kokolopori, where one of the main challenges is protein-calorie deficiency, which itself causes an array of other health problems.

Back to bushmeat. In addition to putting species in risk of extinction, Robert Nasi of CIFOR says "If current levels of hunting persist... bushmeat protein supplies will fall dramatically." So in some ways, the people of Africa -- and its animals --- are damned no matter what.

CIFOR acknowledges that this is a "complex" problem with no easy solution. They recommend re-framing the discussion within the context of the global food crisis. Hopefully the world will sit up and take notice.

Next Page

Issue 25

Sign up for Plenty's Weekly Newsletter