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Article: Population dynamics of Scottish Rock Ptarmigan cycles.
- Article from:
- Ecology
- Article date:
- June 1, 1998
- Author:
CopyrightCOPYRIGHT 1998 Ecological Society of America. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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INTRODUCTION
Cyclic fluctuations of northern rodents, hares, and grouse were an early problem in population ecology (Chitty and Elton 1940), yet the mechanisms remain unresolved (Keith 1963, Lindstrom 1994). Simple model populations with delayed density-dependent growth suggest that cycles may be special cases of unstable dynamics, which include damped oscillations, limit cycles, and chaotic fluctuations (May 1975). Most workers have studied 3-4 yr cycles in rodents, with less attention to long cycles such as the 10-yr ones in grouse (Tetraonidae) and hares (Keith 1963). Here, we show that (1) Scottish Rock Ptarmigan (Lagopus mutus) cycle with a period of 10 yr, and ...