Update: The Western Black Rhino of Africa, a subspecies of Africa's black rhinoceros species, has been declared extinct, according to the latest Red List of Threatened Species from the International Union for Conservation of Nature. The environmental network -- one of the world's most venerable international organizations dedicated to conservation issues, counting 82 states, 111 government agencies, 800 NGOs and thousands of individual scientists among its members -- announced the list in a news release this morning.

Unfortunately, the Western Black is not the only rhino the IUCN lists as a point of concern:

"The subspecies of the White Rhino in central Africa, the Northern White Rhino (Ceratotherium simum cottoni) is currently teetering on the brink of extinction and has been listed as Possibly Extinct in the Wild. The Javan Rhino (Rhinoceros sondaicus) is also making its last stand, as the subspecies Rhinoceros sondaicus annamiticus is probably Extinct, following the poaching of what is thought to be the last animal in Viet Nam in 2010. Although this is not the end of the Javan Rhino, it does reduce the species to a single, tiny, declining population on Java. A lack of political support and will power for conservation efforts in many rhino habitats, international organized crime groups targeting rhinos and increasing illegal demand for rhino horns and commercial poaching are the main threats faced by rhinos."

INFOGRAPHIC: What Twitter Can Do For South African Rhinos

November 8, 2011 According to this intriguing infographic created by researchers at Craigconnects, the non-profit run by Craigslist founder Craig Newmark, organizations dedicated to animal-welfare issues are the most successful advocacy groups making use of social media today. (Click on the image below to see the full infographic.)

The craigconnects study looked at which organizations posted on social media the most often, which ones were most talked about, and which posts had the greatest traction. The results, as depicted on the graph, clearly show that animal issues lead the way when it comes to making a social media splash.

Hopefully some of the organizations making most effective use of the new media include those working to raise awareness of a very specific animal-welfare concern: The illegal poaching of rhinoceros horns in South Africa. That's because new data reveals that the number of rhinos killed in the last 10 months is already higher than that of all of 2010: As of yesterday, according to the World Wildlife Fund's Black Rhino Range Expansion Project, 353 had been killed since January, compared to 333 in 2010 - a number that itself represented an all-time high.

The increased numbers are attributed to higher demand for rhinoceros horn in markets such as Vietnam, where the horn is a popular ingredient in traditional medicine. This comes as the rhino population of Vietnam itself was announced as extinct last month, according to the International Rhino Foundation.

So can social media outlets such as Twitter and Facebook be part of the solution? There are a number of organizations dedicated to rhino preservation that keep regular Twitter feeds, including ProjectRhinoKZN, Rhino Project, Unite Against Poaching and the World Wildlife Fund. Many of these provide links to active campaigns working to enforce an end to rhino poaching.

But if you do decide to follow the links and investigate this issue, and find yourself depressed by the accounts of excessive rhino slaughter, be reassured that there is also some good news about the big, horned beasts out there: The following image shows a black rhino being airlifted from its current, poacher-heavy stomping grounds in South Africa to a new, secret location in the country's Limpopo province. It might not look like the most fun way for a giant mammal to spend the day, but it speaks to the hope of a safer future for an endangered species.