https://www.scientificamerican.com/article/wildlife-trade-entangles-nearly-a-fifth-of-the-planets-vertebrate-animals/

The poaching of elephants, rhinoceroses and tigers regularly makes the news, but these well-known species comprise only a tiny fraction of the global wildlife trade—both legal and illegal. This is a multibillion-dollar industry that impacts animals ranging from softshell turtles and songbirds to rattlesnakes and otters. The exact count of affected species has always been a guess at best, however, because no single organization keeps track of these data.

Now researchers have produced the first such number, and it is colossal: nearly 5,600 species—about 18 percent of the planet’s known terrestrial vertebrate animals—are caught up in the trade. “Almost one in five is a very large number,” says Brett Scheffers, a conservation biologist at the University of Florida and lead author of the study, which was published Thursday in Science. “What’s surprising and important about this work is that, for the first time, we know the sheer magnitude of the global wildlife trade.” Scheffers’s team also predicts which species could be at risk next.