Western States of the US have a real problem with wild horses and burros, with little hope of finding an acceptable solution any time soon. The Bureau of Land Management (BLM) is tasked with the management of these animals, but have their hands tied by states and activists.
Tens of thousands of feral horses and burros are currently being held indefinitely in corrals, with authorities unable to kill or release them, and extremely few private citizens willing and able to provide them homes. Releasing the animals would wipe out native and often endangered wildlife, as food supplies are limited. If they were to be released, most of them would starve anyway, which is the most common fate of the ones who have not yet been caught. These free horses and burros are already taking a heavy toll on native wildlife, and still are mostly unable to find enough food to sustain themselves. Meanwhile, populations of both captive and free animals continue to rise. Birth control methods seem to be the only workable solution, but any method used would first need to be approved by the FDA, and previous attempts to sterilize these equines have met with great public hostility.
For instance, in Arizona, burros were introduced around 1700, and the mining boom in the 1800's brought many more. Lots of these animals were turned loose over the years, with wild populations doubling every 4 or so years. As numbers grew, native species such as quail, big horn sheep and migratory birds began to lose necessary habitat and food resources. Meanwhile, ranching became more and more pervasive, with herds of cattle now competing for the the already sparse vegetation available. With no real predators to control the population, and the ranchers destroying the few predators that were there, BLM finally had to step in and start killing off the herds themselves. Common methods included poisoning watering holes, or chasing down the animals in vehicles until they died from exhaustion. Before long, activists learned what was going on and started raising hell.
In the early 70's the "Wild and Free-Roaming Horses and Burros Act" was passed, which ended the culling, instead allowing people to adopt the excess equines. This was a well-meaning plan to be sure, but almost completely useless, as very few people were interested and the process to adopt is a typical bureaucratic mess. So now we are left with over 50,000 wild horses and burros being held in corrals and costing ~$60 million each year just to feed and water. Meanwhile, plenty of the animals are still running free and reproducing.
So we are left with a ridiculous and heartbreaking situation where federal funds can't be used to kill them, hunting the wild ones isn't permitted, and the captive animals can't be left to starve. Just another example of the grotesque workings of government...
NBC had a pretty good segment about this last year, you can check it out here: https://www.nbcnews.com/leftfield/video/america-s-wild-horse-problem-why-the-trump-administration-ranchers-and-horse-advocates-can-t-agree-how-to-fix-it-970690627548?v=railb&
