Approved for Use: the First Birth Control for Wildlife
Bad Touch In the 1970s, scientists began testing birth-control vaccines, but it wasn't until 2009 that an effective vaccine came to market. Tavis CoburnKeeping wildlife baby-free is a hazardous business In 1989, researchers at the University of California at Davis invented PZP, the first birth-control vaccine for animals other than humans. When injected, PZP causes a female's immune system to block sperm from her eggs, offering a humane method of keeping populations in check. The compound worked in elephants, donkeys and deer, but it had a troubling side effect: the animals stayed in heat longer than normal. In one trial, deer were fertile for six months instead of one. An amorous deer is a dangerous deer. While pursued by stags, females often crash into backyards and run into traffic (deer cause about 1.5 million car crashes each year). Insurance claims for deer collisions are three times higher in November, when the...