CHARLES J. KREBS,¹ RUDY BOONSTRA,² STAN BOUTIN,³ A.R.E. SINCLAIR<sup>4

1</sup>Charles J. Krebs ( ), an ecologist in the Department of Zoology at the University of British Columbia, Vancouver, B.C. V6T 1Z4, has been studying population cycles for 41 years krebs@zoology.ubc.ca
²Rudy Boonstra, a population biologist in the Division of Life Sciences, University of Toronto, Scarborough, Ontario M1C 1A4, is interested in the role of stress in population dynamics of mammals.
³Stan Boutin is an ecologist in the Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9; he has been studying northern mammal populations for 21 years.
⁴A. R. E. Sinclair, also with the Department of Zoology at the University of British Columbia, is a population and community ecologist who works extensively in East Africa on ungulate and bird populations and in the Yukon on hare population cycles.