Shifting age structure of house mice during a population outbreak
Duncan R. Sutherland A B C G , Peter B. Banks D , Jens Jacob E F and Grant R. Singleton B EA School of Biological Sciences, Monash University, Clayton, Vic. 3800, Australia.
B Pest Animal Control Cooperative Research Centre, GPO Box 284, Canberra, ACT 2601, Australia.
C Current Address: School of Biological Sciences and Biotechnology, Murdoch University, South Street, Murdoch, WA 6150, Australia.
D School of Biological, Earth and Environmental Sciences, The University of New South Wales, NSW 2052, Australia.
E CSIRO Sustainable Ecosystems, GPO Box 284, Canberra, ACT 2601, Australia.
F Federal Biological Research Centre for Agriculture and Forestry, Institute for Nematology and Vertebrate Research, Toppheideweg 88, 48161 Münster, Germany.
G Corresponding author. Email: d.sutherland@murdoch.edu.au
Wildlife Research 31(6) 613-618 https://doi.org/10.1071/WR04010
Submitted: 2 February 2004 Accepted: 30 August 2004 Published: 23 December 2004
Abstract
A technique to age wild house mice, Mus domesticus, in Australia using the dry weight of the eye lens based on known-age mice from semi-natural enclosures is described and presented for 3–32-week-old mice. At four sampling periods from November 2000 to September 2001, the age frequency distributions of free-living house mice were determined using this relationship. The distributions of ages shifted between seasons from relatively young animals at the beginning of the breeding season (November 2001), coinciding with low mouse abundance, to progressively older distributions in each sample as breeding continued, ending with the cessation of breeding and a population crash before the last sample. No significant difference was detected between the sexes at any of the four periods. These results are consistent with the suggestion that the formation of mouse outbreaks requires a shift in age structure towards younger mice.
Acknowledgments
We thank the Lester, Mead, Pole and Stone families for access to their properties and J. G. Cody, M. A. Davies, C. G. Hodkinson, D. A. Jones, K. E. Leslie, S. Walde, J. E. Winsbury, A. Ylönen and H. Ylönen for help with the trapping. For assistance with eye lens extraction and weighing we thank R. Allport, V. Guthrie and L. Sim. We are indebted to two anonymous referees for their insightful comments and to C. J. Krebs for his helpful suggestions on an earlier draft. Trapping and manipulations were done in compliance with the regulations of CSIRO’s Animal Ethics Committee [permit 00-01 06(2) Division of Sustainable Ecosystems]. The project was funded in part by the Australian Centre for International Agriculture Research (AS1/98/36), the Grains Research and Development Cooperation (CSV16 and CSV15) and the Pest Animal Control Cooperative Research Centre.
Barker, S. C. , Singleton, G. R. , and Spratt, D. M. (1991). Can the nematode Capillaria hepatica regulate abundance in wild house mice? Results of enclosure experiments in southeastern Australia. Parasitology 103, 439–449.
Chambers, L. K. , Singleton, G. R. , and Hood, G. M. (1997). Immunocontraception as a potential control method of wild rodent populations. Belgian Journal of Zoology 127, 145–156.
Rice, W. R. (1989). Analyzing tables of statistical tests. Evolution 43, 223–225.
Ylönen, H. , Jacob, J. , Runcie, M. J. , and Singleton, G. R. (2003). Is reproduction in the Australian house mouse (Mus domesticus) constrained by food: a large-scale field experiment. Oecologia 135, 372–377.
