I just returned from Brandon, where the 50th Annual North American Moose Conference and the 8th International Moose Symposium were combined and held. There were people from North America and Eurasia attending the meetings, but I only managed to intermingle for a short while; I was a one day attendant during a set of meetings, field trips and social events that lasted several days. I really enjoyed myself and it seemed to me that was the feeling that captured the general mood.
I heard several talks about moose and listening to those presentations was like music to my ears. I heard that as a species, moose seem to be faring well, although populations in some areas have declined precipitously. I live in one of those areas – northwestern Ontario – I was there to provide an overview of the factors driving moose and white-tailed deer populations in the Kenora District of Ontario.
I don’t think my presentation was quite as lucid as I had hoped and I know I made an error when I couldn’t see the labelling on one of the graphs I had inserted into the power point presentation. Unable to read the labels and the legend, I promptly got the deer and moose stats wrong. Oh well, that will be corrected during the final write-up and anyway, I think the crowd got the gist of my presentation.
It’s still an emerging consensus, but it appears that in much of eastern North America’s moose range, moose populations are limited by the presence of a parasite called brain worm. In that eastern, wetter, more highly forested biome, the parasite is commonly found in populations of white-tailed deer, where it seems to affect deer minimally, if at all. However, when moose become infected with brain worm, the animal often dies.
In the western, drier and more open ranges of North America, there is little to no incidence of brain worm in deer or moose. The presence of brain worm seems to do a good job of helping to explain how moose populations are compromised by high populations of deer.
It seems that in the east, once deer densities exceed about 4 deer/km2, moose populations decline. When deer densities are low, rates of transmission of the parasite from deer to moose rarely occurs.
There’s a lot more to the stories on moose and deer dynamics, but one of the topics of interest is how moose recover from low densities. In western Manitoba, southern Saskatchewan and south-eastern Alberta – the Canadian prairies – the thinking is that moose populations have been on the rise coincident with a decline in the number of rural farmers and ranchers living on the landscape. There’s evidence that incidence of illegal, unregulated hunting wasn’t necessarily high, as moose populations were long-depressed in the prairies, but it didn’t take a lot of moose hunting to keep populations low. As people abandoned their homesteads, more and more moose managed to find refuge and survive. Today, moose populations in grain and cattle country are robust.
The eastern forest areas where moose have recently declined are the same areas where deer populations simultaneously surged. But recent winter of deep snow and cold have knocked deer populations back; if they stay low or decline further, moose populations may be poised to recover.
A growing concern is that where moose populations are lowest, recovery could be jeopardized by legal, but unregulated hunting (Aboriginals and Metis have the constitutional Right to hunt and fish; the present interpretation is this means the hunting of moose by some can be done at any time of the year and there are no seasons or bag limits on the harvest).
The moose harvest by such individuals may not have to be much to prevent severely depressed moose populations from recovery.
Unregulated hunting is certainly not the only issue regarding moose population (or other game species) recovery dynamics. But to help solve the puzzle as to how to effectively manage moose populations in particular, it’s a factor that needs a lot more attention than society at large has lately been willing to give it.