Polars vs. Grizzlies
The caption for your "Featured Photos" below says:
Polars vs. Grizzlies July 8, 2014
"Climate change and the resulting competition for limited resources are bringing the giant polar bear and the aggressive grizzly bear into closer contact."
This is simply not true. All recent hybridization events documented (2006-2013) occurred because a few male grizzlies traveled over the sea ice into polar bear territory and found themselves a polar bear female to impregnate.
These events did not occur on land during the ice-free season (which is late summer/early fall), but on the sea ice in spring (March-May).
Grizzlies have been documented wandering over the sea ice of the western Arctic since at least 1885 (Doupe et al. 2007) and the presence in this region of hybrid grizzly/polar bear offspring is not an indicator of declining summer sea ice and therefore, not due to climate change.
Leading polar bear specialist Ian Stirling knows this. He said as much in an interview with National Geographic News reporter John Roach when the first hybrid was shot back in 2006 (May 16, 2006),
“Stirling said grizzly bears have been showing up in the Canada's western Arctic as far north as Banks Island and Victoria Island in the province of Nunavut periodically for the past 50 years.
The hybrid, he said, is "definitely not" a sign of climate change.” [my bold]
Dr. S. Crockford, zoologist