Some of the Lake Superior region's last herd of caribou got a free helicopter ride in recent days as Ontario wildlife authorities rush to save at least some of the animals from certain death at the hands of wolves.

Through Monday nine caribou, one bull and eight cows, were tranquilized and taken aboard helicopters from Michipicoten Island on Lake Superior to the Slate Islands, according to the Ontario Ministry of Natural Resources and Forestry.

It wasn't clear early Tuersday if the project would continue. The ministry's original goal was to move between 10 and 12 animals total.

The Michipicoten herd has been decimated in recent years after wolves crossed an ice bridge from the Ontario mainland. Where more than 450 roamed before the wolves arrived in 2014 as few as 30 caribou - the last in the entire region - were left on the island by the weekend.

Ironically, nearly all of Michipicoten caribou are descendants of animals transported from the Slate Islands years ago after wolves had become established there.

Now, the Slate Islands caribou herd has been all but wiped out and most wolves there have either starved or moved on, making the island apparently safe again for the relocated caribou from Michipicoten.

Ontario provincial officials in December, bowing to pressure from caribou supporters and tribal officials, agreed to move some of the Michipicoten caribou because they represent the last woodland caribou remaining in a region where they were once widespread.

Some caribou supporters have been critical of the Ontario Ministry of Natural Resources and Forestry for waiting too long to rescue some caribou. They also have argued that the caribou should be relocated to more than one island to better assure that at least some survive to rebuild the Lake Superior region herd.

Moving the animals is part of a confusing, expensive and complicated chess game as climate change and a trend toward unpredictable ice bridges between Ontario's North Shore and the islands confound wildlife experts. Scientists say that for centuries before European settlement of the region, caribou thrived both on the islands and the mainland surrounding Lake Superior. Ice bridges occurred regularly between the mainland and the islands, allowing caribou and wolves to move freely back and forth, avoiding and seeking each other.

Now, caribou have been trapped on the islands, with wolves moving out across ice bridges that form only occasionally. By the time caribou sense there are too many wolves, it's too late for them to leave the islands, and there are no caribou remaining on the mainland to resupply the islands.

Caribou were common across the Lake Superior region through the 1800s but had mostly disappeared from Michigan and Minnesota by the mid-1900s. They have been declining in parts of Ontario as well, pushed north out of the Lake Superior region by development, logging and the expansion of whitetail deer and wolves. Efforts to restock a Minnesota caribou herd were abandoned years ago because too many non-native whitetail deer have infiltrated the state's far northern forest. Deer carry a parasitic brain-worm that, while harmless to deer, is fatal to caribou. Wildlife officials say it is impossible to have a successful caribou population anywhere near a large whitetail deer population.