Lack of behavioral responses of moose (Alces alces) to high ambient temperatures near the southern periphery of their range

• Published in: Canadian Journal of Zoology
• Main Authors: Lowe, Stacey J., Patterson, Brent R., Schaefer, James A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 2010
• Subjects: Canada; Alces alces
• Online Access: http://dx.doi.org/10.1139/z10-071; http://www.nrcresearchpress.com/doi/full-xml/10.1139/Z10-071; http://www.nrcresearchpress.com/doi/pdf/10.1139/Z10-071

Although fundamental factors limiting geographic ranges are understood for many animal species, there is less certainty regarding how such factors influence the behavior of individuals near distributional edges. We tested the hypothesis that climate limits the southern distribution of moose ( Alces alces (L., 1758)) by documenting space use and behavior of 36 females at the margin of the species’ range in Ontario, Canada. We assessed temperature differences among habitats and related changes in seasonal habitat use and daily movement patterns in response to temperature. Ambient temperatures frequently exceeded the thresholds of –5 °C (winter) and 14 °C (summer), above which moose are supposed to be thermally stressed. We detected no differences in habitat use relative to thermoregulation thresholds. However, moose exhibited reduced movement when snow was deep and were more active at dawn and dusk. Low variability in temperature among habitat types implied that functional thermal shelters were absent. We suggest 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. Additional evidence linking temperatures with negative responses is necessary before the prevalent hypothesis of heat stress limiting the southern distribution of moose can be fully assessed.