Ethiopian lions, Florida panthers, Sumatran rhinos and Yangtze porpoises are among the endangered species in the news this week.

Well that was Interesting: The Internet was abuzz this week with "news" about how a pack of lions in Ethiopia supposedly saved a teenage girl from kidnapping rapists. That story actually dates back to 2005 but—as happens online from time to time—it suddenly gained new life and spread like wildfire.

I first encountered the story last year when researching my article about the last 20 Ethiopian lions, which all live in a rather miserable zoo in Addis Ababa. I never found a reputable primary source to the news about the girl's protectors, so I have doubts that it really happened. It's a good story, though, and it's interesting how it grabbed the public's attention this week in a year filled with so many horrible rape cases. It also led thousands of new readers to my article, which can only mean good things for these rare lions.

Best Read of the Week: Kenya's The Star interviews Save the Elephants founder Ian Douglas-Hamilton. Agatha Ngotho asks why Africans should be concerned about elephant poaching and gets some great answers.

Shrinking Violets: Invasive cane toads have killed so many of Australia's native wildlife that one species, a goanna called the yellow-spotted monitor (Varanus panoptes), is experiencing a size change. All goannas over a certain size are big enough to try to eat toxic cane toads, which turns out to be their last meals. Scientists are having trouble finding any large lizards, which probably means they big ones are all dead.

Count That: A new count finds that populations of the Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) have dropped by 50 percent in the past six years to a low of 1,000. Oddly, that's the same number determined by some of the same organizations two years ago.

Well, They Tried: Back in 2011 an orangutan named Semeru became the first zoo-born orang to be released back into the wild. He did okay for a few years, but now we have word that he has died from a snake bite. I remember the TV show Orangutan Island a few years ago showing how captive-born orangutans lack the necessary fear of snakes that would keep them alive in the wild. Training the apes that snakes are dangerous is an important survival tool for any orangutans being released back into nature, as Semeru's death illustrates.

Best News of the Week: A captive-raised Florida panther, who was rescued as a kitten two years ago after his mother was killed, has been released back into the wild. Will he survive? Who knows, but with only 160 or so Florida panthers left, every cat counts.

Worst News of the Week, Part 1: Augh. The number of rhinos poached in South Africa each year continues to rise. As of April 3, the number stood at 203 rhinos killed for their horns (and it's probably even higher by now). Only 13 rhinos were killed in all of 2007. Last year there were 668 killed. South Africa is home to well over 90 percent of the world's rhinos.

Worst News of the Week, Part 2: Double-augh. New research shows that there are far fewer Sumatran rhinos (Rhinoceros sondaicus) left in the wild than previously believed. Previous estimates put the number at 180. A new estimate put out by the IUCN this week lowers that to 100. At this rate, we'll be in double digits before the end of the year.

Well, on that happy note that's it for this time around. For more endangered species news stories throughout the week, read the regular Extinction Countdown articles here at Scientific American, "like" Extinction Countdown on Facebook, or follow me on Twitter.

Photos: Ethiopian lion by Joerg Junhold and Klaus Eulenberger, Leipzig Zoo. Used with permission. A captive Sumatran rhino named Ratu and her baby, courtesy of International Rhino Foundation