On Understanding the Boreal Forest Ecosystem

I have spent the last 40 years studying the Yukon boreal forest. When I tell this to my associates I get two quite different reactions. First, on the positive side they are impressed with the continuity of effort and the fact that we have learned a great deal about the interactions of species in the Canadian boreal forest (Krebs, Boutin, and Boonstra 2001). Alternatively, on the negative side, I am told I am at fault for doing something of no practical management importance for so long when there are critical conservation problems in our Canadian backyard. Clearly I prefer the positive view, but everyone can decide these issues for themself. What I would like to do here is to lay out what I think are the critical issues in the Canadian boreal forest that have not been addressed so far. I do this in the hope that someone will pick up the torch and look into some of them.

The first issue is that ecological studies of the boreal ecosystem are completely fractionated. The most obvious division is that we have studied the boreal forest in the southwest Yukon with few concurrent studies of the alpine tundra that rises above the forest in every range of mountains. The ecotone between the forest and the tundra is not a strict boundary for many plant species or for many of the vertebrate species we have studied. On a broader scale, there are few studies of aquatic ecosystems within the boreal zone, either in lakes or streams, another disconnect. The wildlife management authorities are concerned with the large vertebrates – moose, bears, caribou, mountain sheep – and this work tends not to tie in with other work on the smaller species in the food web. Interests in the carbon dynamics of the boreal zone have greatly increased but these studies in Canada are also completely disconnected from all other ecological studies that consider population and community dynamics. I think it is fair to say that carbon dynamics in the boreal forest could turn out to be a very local affair, and too much generalization has already been made with too little spatial and temporal data.

One could consider the ecology of the boreal zone like a puzzle, with bits of the puzzle being put together well by researches in one particular area, but with no view of the major dimensions of the total puzzle. This is readily understood when much of the research is done as part of graduate thesis work that has a limit of 4-5 years before researchers move on to another position. It is also a reflection of the low funding that ecology receives.

Within the Yukon boreal forest there are several areas of research that we have not been able to address in the time I and my many colleagues have worked there. Mushroom crops come and go in apparent response to rainfall (Krebs et al. 2008) but we do not know the species of above ground mushrooms and consequently do not know if their fluctuations are uniform or if some species have specialized requirements. Since fungi are probably the main decomposers in this ecosystem, knowing which species will do what as climate changes could be important. On a practical level, foresters are determined to begin logging more and more in the boreal zone but we have no clear understanding of tree regeneration or indeed any good studies of forest succession after fire or logging. Since logging in northern climates is more of a mining operation than a sustainable exercise, such information might be useful before we proceed too far. If the turnaround for a logged forest is of the order of 300 years, any kind of logging is unsustainable in the human time frame.

The list goes on. Snowshoe hare cycles vary greatly in amplitude and we suspect that this is due to predator abundance at the start of any 10 year cycle (Krebs et al. 2013).  The means to test this idea are readily available – satellite telemetry – but it would require a lot of money because these collars are expensive and need to be deployed on lynx, coyotes, and great-horned owls at least. And it needs to be done on a landscape scale with cooperating groups in Alaska, the Yukon, the Northwest Territories, and British Columbia at least. Large-scale ecology to be sure, but the results would be amazing. Radio-telemetry has the ability to interest the public, and each school in the region could have their tagged animals to follow every week. Physicists manage to convince the public that they need lots of money to do large experiments, but ecologists with down to earth questions are loath to ask for a lot of money to find out how the world works on a large scale.

Migratory songbirds have been largely ignored in the boreal forest, partly because they leave Canada after the summer breeding period but at least some of these songbirds appear to be declining in numbers with no clear reason. Yet studies on them are virtually absent, and we monitor numbers in imprecise ways, and continue to mark the position of the deck chairs on the Titanic with no understanding of why it is sinking.

Insect populations in the boreal forest are rarely studied unless they are causing immediate damage to trees, and consequently we have little information on their roles in ecosystem changes.

At the end of this list we can say in the best manner of the investigative reporter why did you not do these things already? The answer to that is also informative. It is because almost all this completed research has been done by university professors and their graduate students and postdocs. What has been done by all my colleagues is amazing because they are not in charge of the boreal forest. The people are, via their governments, provincial and federal. The main job of all of us when this research in the Yukon boreal forest was being done has been education –to teach and do research that will train students in the best methods available. So if you wish to be an investigative reporter, it is best to ask why governments across the board have not funded the federal and provincial research groups that had as their mandate to understand how this ecosystem operates. Because all these questions are about long-term changes, the research group must be stable in funding and person-power in the long term. There is nothing I have seen in my lifetime that comes close to this in government for environmental work except for weather stations. In the short term our governments work to the minute with re-election in sight, and long term vision is suppressed. The environment is seen as a source of dollars and as a convenient garbage can and science only gets in the way of exploitation. And in the end Mother Nature will take care of herself, so they hope. Perhaps we need a few Bill Gates’ types to get interested in funding long-term research.

But there remain for ecologists many interesting questions that are at present not answered, and will help us complete the picture of how this large ecosystem operates.

Krebs, C.J., S. Boutin, and R. Boonstra, editors. 2001. Ecosystem Dynamics of the Boreal Forest: the Kluane Project. Oxford University Press, New York.

Krebs, C.J., P. Carrier, S. Boutin, R. Boonstra, and E.J. Hofer. 2008. Mushroom crops in relation to weather in the southwestern Yukon. Botany 86:1497-1502.

Krebs, C.J., K. Kielland, J. Bryant, M. O’Donoghue, F. Doyle, C. McIntyre, D. DiFolco, N. Berg, S. Carrier, R. Boonstra, S. Boutin, A.J. Kenney, D.G. Reid, K. Bodony, J. Putera, and T. Burke. 2013. Synchrony in the snowshoe hare cycle in northwestern North America, 1970-2012. Canadian Journal of Zoology 91:562-572.

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