Clouds of bone dust will waft through the streets of New York today. There will be a dramatic crushing of an entire ton of illegally poached elephant ivory in Times Square this morning in an effort to stamp out the practice.

The crush is the second one conducted by the U.S. Fish and Wildlife Service. The first one took place in Denver, Colorado in 2013 and six tons of seized elephant ivory were crushed.

The motivation is to show the world that the only place to enjoy seeing ivory is on an elephant.

This is why the decision was made to crush illegal ivory instead of selling it to fund future wildlife protection schemes, which is arguably a good cause. Selling poached ivory, even with charitable intentions, creates a confusing message about whether buying ivory is acceptable or not. It also gives poachers a great excuse to sell new ivory: "Oh, but this was seized from poachers and is raising money for anti-poaching." Irony abounds.

But crushing it to dust sends out a firm, clear message. Ivory shouldn't be desired, bought or sold.

In 1989, the federal African Elephant Conservation Act put a ban on the import of African elephant ivory to the United States from any country unless the elephant was killed before 1989.

Despite this, there were two government sales, held in 1999 and 2008. When elephants (such as those in game reserves) die naturally, the park will confiscate the ivory so that poachers don't steal it. Consequently, legal ivory reserves do pile up. The justifications for selling these reserves included the belief that they were "flooding the market" and devaluing the ivory so that it was less profitable for poachers, and the ivory wasn't collected by killing elephants. However, this arguably just swayed public opinion from buying ivory being unacceptable toward it being OK.

The ban on new ivory also meant that poachers would go to great lengths to artificially age their recently-gathered ivory. Some tricks include burying it for a few days or rubbing it with charcoal so that it can be classified as antique ivory with "wear and tear."

Artificially aging the ivory doesn't mean that the ivory can't be tested to find out the real age. But the tests are complicated to interpret. Elephant tusks are like human hair: a sample from the root is required to establish the age of the owner. Ivory from extremely old elephants, especially material from the end of the tusk, may be 50 or even up to 70 years old. In other words, easy to pass off as an antique.

Some scientists think that the crushing is a little hasty, however. Samuel Wasser, from the University of Washington, who created an elephant-gene map of Africa to find out where ivory had been poached, says "unfortunately, it destroys evidence." Wasser wants the opportunity to take a small sample of ivory from every tusk before it is crushed so that they can find out where the ivory originated. By identifying where the ivory was poached, countries involved are put under pressure to take action. You can read about Wasser's influential research here.

The illegal ivory trade is a brutal business and is endangering the lives of some of the most majestic animals on the planet. The trade needs to end, but will this Times Square ivory crushing be the tipping point?

[Via U.S. Fish and Wildlife Service]