The island is home to over 550 free-roaming Sable Island horses, protected by law from human interference. This feral horse population is likely descended from horses confiscated from Acadians during the Great Expulsion and left on the island by Thomas Hancock, Boston merchant and uncle of John Hancock. In the past, excess horses were rounded up, shipped off the island, and sold, many used in coal mines on Cape Breton Island, Nova Scotia. In 1960, the Canadian Government, under the Canada Shipping Act, gave the horse population full protection from human interference.