Learn how plants respond to higher atmospheric CO2 concentrations

How does rising atmospheric CO2 affect marine organisms?

Click to locate material archived on our website by topic

Moose on the Loose in a Warming Canadian Environment
Lowe, S.J., Patterson, B.R. and Schaefer, J.A. 2010. Lack of behavioral responses of moose (Alces alces) to high ambient temperatures near the southern Periphery of their range. Canadian Journal of Zoology 88: 1032-1041.

Lowe et al. write that "intuitively, we would expect that a large northern ungulate with low tolerance for high temperatures would gradually be pushed out of the southern reaches of its range as the climate continues to warm and temperature conditions become increasingly unfavorable," the logic being that "persistent temperatures above the upper critical limit will suppress foraging time and consequently cause mass loss during the summer, and that this reduced condition could affect overwinter survival and productivity," citing the work of Schwartz and Renecker (1998).

What was done
The authors "tested the hypothesis that climate limits the southern distribution of moose (Alces alces) by documenting space use and behavior of 36 females at the margin of the species' range in Ontario, Canada." This they did in 2006, 2007 and 2008 via the use of "global positioning system (GPS) telemetry to study their habitat use and movement," in an attempt "to document behavioral mechanisms indicative of adaptive responses to warm temperatures," which work was conducted during periods of the year when ambient temperatures frequently exceeded known critical thresholds (-5°C in winter and 14°C in summer) that had been demonstrated by Dussault et al. (2004) to induce heat stress in moose.

What was learned
Lowe et al. say they "detected no differences in habitat use relative to thermoregulation thresholds," which finding they deemed to be particularly important during the summer, when they report that the temperatures of all habitat classes greatly exceeded -- by an average of 6°C, but by as much as 19°C the first week of August 2006 -- the 14°C threshold for a large extent of the day and partially during the night.

What it means
The three Canadian researchers conclude that "moose in their southern range either ameliorate heat stress at a finer resolution than we measured or are more resilient to temperature than previously thought," thereby casting significant doubt upon what climate alarmists "intuitively" claim will occur in a warming world.

Dussault, C., Ouellet, J.-P., Courtois, R., Huot, J., Breton L. and Larochelle, J. 2004. Behavioural responses of moose to thermal conditions in the boreal forest. Ecoscience 11: 321-328.

Schwartz, C.C. and Renecker, L.A. 1998. Nutrition and energetics. In: Franzmann, A.W. and Schwartz, C.C. (Eds.), Ecology and Management of the North American Moose. Smithsonian Institution, Washington, DC, USA, pp. 441-478.

Reviewed 26 January 2011