MNR biologist Scott McAughey said climate change has been noticeable in recent years and may be partially to blame for the drop in moose numbers.
"This is a real world example of the added impact of a warming climate," said McAughey.
The MNR's latest population estimates for Wildlife Management Unit 6 -- north of the CN Railway tracks -- are less than half of what they were in 2004. After nearly three weeks of aerial survey work, which concluded Jan. 19, the population estimates for 2007 are a paltry 650 moose, a significant drop since their 2004 estimate of 1,700 moose. In addition, they estimate that only 10 per cent of population are calves, compared to the normal average of 20 per cent calves.
McAughey noted this latest negative shift in WMU 6 is mirrors similar trends in units 7B and 7A, where moose populations have already dropped significantly.
In unit 7B, a huge area that extends from Kenora to Sioux Narrows, a survey last year tabulated an estimated 650 moose, down from 1,100 in 2003 and 1,700 in 2000. In unit 7A, the Aulneau Peninsula, the last MNR estimate in 2003 pegged the number of moose at about 350, down from the 600 estimated in 2000. Aerial surveys on unit 7A began last weekend.
McAughey said several well-known natural factors brought on by increasing deer numbers contribute to the decline of moose populations such as brainworm infections, predators like wolves and more incidents of winter tick infestations. The additional burden of a warming climate leads to heat stress in moose which are naturally more accustomed to colder temperatures.
Art Rodgers, a research scientist at the MNR's Centre for Northern Forest Ecosystem Research at Lakehead University in Thunder Bay, theorizes that this heat stress may be also be the cause of mortality rates in moose. He said moose get stressed at temperatures above 14C in the summer and anything above -5C in the winter.
The changing climate may be also affect the rut (the mating rituals) of moose. Rodgers said cold weather seems to trigger mating for moose. When mating occurs later in the season, the calves are born later the following spring, and don't have enough time to mature and survive the following winter.
"So one way or the other, moose are in trouble," said Rodgers.