David Ramsay, Ontario’s Minister of Natural Resources, said if sea ice continues to melt, the province’s polar bears could not only lose habitat and food sources but also be prevented from mating with Manitoba bears.

Polar bears in southern Hudson Bay will be among the early casualties of dramatic climate change because their environment is likely to see the most drastic and sudden changes, government scientists say. Ontario has ordered a three-year study but government research scientist Marty Obbard said the bears are already starting to suffer.

Weather will also warm in southern Ontario, bringing insects like Lyme disease-carrying black-legged ticks and an influx of white-tailed deer, which can carry brainworm — fatal to some animals.