The rescue and release of 200 starving orphan bear cubs in Ontario and Manitoba will provide biologists with a rare chance to monitor what happens to the cubs after they've been cared for by humans.

Last summer, wildlife officials saved hundreds of black bear cubs after a severe drought wiped out much of the berry crop that the bears depend on for their survival. Wildlife officials say some cubs were little more than furry skeletons when they were rescued.

The cubs were orphaned when their mothers headed into cities and towns to look for food.

"These bears, considered to be a nuisance, or possibly a threat to public safety, were shot," said Linda Rayburn of Aspen Valley Wildlife Sanctuary in Rosseau, 175 kilometres north of Toronto. "And if it happened to be a mother with cubs, the cubs would be left as orphans."

Wildlife rehabilitation centres across North America nurse orphan cubs every year and then release them.

In this case, 60 orphans are being fitted with radio collars and they'll be monitored for two years.

Scientists are trying to see what proportion of the bears survive in the wild and if they find natural food sources or become nuisance animals.

The bears are being released now and will have to subsist on ground vegetation and insects until the berries appear. The next four weeks will be critical to their long-term survival.