Nasa researchers have dropped 90 ducks into holes in Greenland's fastest moving glacier, the Jakobshavn Glacier in Baffin Bay, between Greenland and Canada.
The toys have each been labelled with the words "science experiment" and "reward" in three languages, along with an e-mail address.
If they are found scientists will be able to track how the water moves through the ice and provide information about the movement of glaciers. Scientists are still unsure about why glaciers speed up in summer and head towards the sea.
Alberto Behar of Nasa's Jet Propulsion Laboratory in California said none of the ducks had been reported yet. "We haven't heard back but it may take some time until somebody actually finds it and decides to send us an e-mail that they have found it," he said. "These are places that are quite remote so there aren't people walking around."