Considering the enormous literature on their laboratory cousins, and their importance as pests, there is a remarkable dearth of studies of wild brown rats, Rattus norvegicus. Our research provides an overview of the problems they cause, with a focus on their diseases. Following a large-scale post-mortem study of the pathogens of wild rats on and around farms, the chapter presents studies of both physiological and behavioural resistance to control. In particular, this involves studies of neophobia, which link, in the case of Toxoplasma gondii to parasite-altered behaviour and the phenomenon of kamikaze rats. As a framework to understanding rat problems, and their control, our research presents detailed information on their ecology, population dynamics, and behaviour.

David W. Macdonald
Manuel Berdoy
Joanne P. Webster


Macdonald, D.W., Fenn, M.P.G., and Gelling, M. (2013). The natural history of rodents: preadaptations to pestilence. In A.P. Buckle and R.H. Smith, eds.  Rodent Pests and their Control. 2nd Edition. CABI Publishing, Wallingford.

Macdonald, D. and Burnham, D. (2010). The State of Britain’s Mammals—a Focus on Invasive Species. PTES, London.

Quy, R.J. and Macdonald, D.W. (2008). Common Rat. In S. Harris and D.W. Yalden, eds. Mammals of the British Isles: Handbook. The Mammal Society.

Berdoy, M. and Drickammer, L. (2007). Comparative social organisation and life history of Rattus and Mus. In J. Wolff and P. Sherman, eds. Rodent Societies: An Ecological and Evolutionary Perspective, pp. 380–392.University of Chicago Press.

Macdonald, D.W., King, C.M., and Strachan, R. (2007). Introduced species and the line between biodiversity conservation and naturalistic eugenics. In D. Macdonald and K. Service, eds.  Key Topics in Conservation Biology, pp. 186–205. Blackwell Publishing, Oxford.

Berdoy, M. (2002). The laboratory rat: A natural history. (27 minute film). <>.

Webster, J.P. (2001). Rats, cats, people and parasites: the impact of latent toxoplasmosis on behaviour. Microbes and Infection, 3, 1037–1045.

Berdoy, M.L., Webster, J.P., and Macdonald, D.W. (2000). Fatal attraction in Toxoplasma-infected rats: a case of parasite manipulation of its mammalian host. Proceedings of the Royal Society B, 267, 1591–1594.

Macdonald, D.W., Mathews, F., and Berdoy, M.L. (1999). The behaviour and ecology of Rattus norvegicus: from opportunism to kamikaze tendencies. In G.R. Singleton, L.A. Hinds, H. Leirsand, and Z. Zhang, eds. Ecologically-based management of rodent pests. ACIAR Monograph No. 59, pp. 49–80. Australian Centre for International Agricultural Research, Canberra.

Brunton, C.F.A. and Macdonald, D.W. (1996). Measuring the neophobia of individuals in different populations of wild brown rats. Journal of Wildlife Research, 1, 7–14.

Macdonald, D.W. and Fenn, M.G.P. (1995). Rat ranges in arable areas. Journal of Zoology, 236, 349–353.

Natynczuk, S.E., Macdonald, D.W., and Tattersall, F.H. (1995). Morphology and chemistry of brown rat, Rattus norvegicus, preputial and clitoral glands. Journal of Chemical Ecology, 21, 247–260.

Berdoy, M.L., Smith, P., and Macdonald, D.W. (1995a). Stability of social-status in wild rats: age and the role of settled dominance. Behaviour, 132, 193–212.

Berdoy, M.L., Webster, J.P., and Macdonald, D.W. (1995b).The manipulation of rat behaviour by Toxoplasma gondii. Mammalia, 59, 605–613.

Berdoy, M.L., Webster, J.P., and Macdonald, D.W. (1995c). Parasite-altered behaviour: is the effect of Toxoplasma gondii on Rattus norvegicus specific? Parasitology, 111, 403–409.

Fenn, M.G.P. and Macdonald, D.W. (1995). Use of middens by red foxes: risk reverses rhythms of rats. Journal of Mammalogy, 76, 130–136.

Webster, J.P., Ellis, W.A., and Macdonald, D.W. (1995a). Prevalence of Leptospira and other zoonoses in wild brown rats on UK farms. Mammalia, 59, 615–622.

Webster, J.P., Ellis, W.A., and Macdonald, D.W. (1995b). Prevalence of Leptospira spp in wild brown rats (Rattus norvegicus) on UK farms. Epidemiology and Infection, 114, 195–201.

Webster, J.P., Lloyd, G., and Macdonald, D.W. (1995c). Q fever (Coxiella burnetti) reservoir in wild brown rat (Rattus norvegicus) populations in the UK. Parasitology, 110, 31–35.

Webster, J.P. and Macdonald, D.W. (1995a). Cryptosporidiosis reservoir in wild brown rats (Rattus norvegicus): first report in the UK. Epidemiology and Infection, 115, 207–209.

Webster, J.P. and Macdonald, D.W. (1995b). Parasites of wild brown rats, Rattus norvegicus, on UK farms. Parasitology, 111, 247–255.

Webster, J.P., Brunton, C.F.A., and Macdonald, D.W. (1994). Effect of Toxoplasma gondii upon neophobic behaviour in wild brown rats, Rattus norvegicus. Parasitology, 109, 37–43.

Berdoy, M. (1994). Making decisions in the wild: constraints, conflicts and communication in foraging rats. In B.G. Jr. Galef and P. Valsechhi, eds.  Behavioural Aspects of Feeding, Ettore Majorana International Life Sciences Series, Vol 12, pp. 289–313. Harwood Academic Publishers, Chur, Switzerland.

Macdonald, D.W. and Fenn, M.G.P. (1994). The natural history of rodents: preadaptations to pestilence. In A.P. Buckle and R.H. Smith, eds.  Rodent Pests and Their Control, pp. 1–21. CAB International, Wallingford.

Natynczuk, S.E. and Macdonald, D.W. (1994a). Analysis of rat haunch odor using dynamic solvent effect and principal component analysis. Journal of Chemical Ecology, 20, 1859–1866.

Natynczuk, S.E. and Macdonald, D.W. (1994b). Scent, sex, and the self-calibrating rat. Journal of Chemical Ecology, 20, 1843–1857.

Webster, J.P. (1994a). Prevalence and transmission of Toxoplasma gondii in wild brown rats, Rattus norvegicus. Parasitology, 108, 407–411.

Webster, J.P. (1994b). The effect of Toxoplasma gondii and other parasites on activity levels in wild and hybrid Rattus norvegicus. Parasitology, 109, 583–589.

Smith, P., Berdoy, M., Smith, H.R., and Macdonald, D.W. (1993). A new aspect of warfarin resistance in wild rats: benefits in the absence of poison. Functional Ecology, 7, 190–194.

Brunton, C.F.A., Macdonald, D.W., and Buckle, A.P. (1993). Behavioral resistance towards poison baits in Brown rats, Rattus norvegicus. Applied Animal Behaviour Science, 38, 159–174.

Berdoy, M.L. and Macdonald, D.W. (1991). Factors affecting feeding in wild rats. Acta Oecologica-International Journal of Ecology, 12, 261–279.

Berdoy, M. and Evans, S. (1990). An automatic recording system for identifying individual small animals. Animal Behaviour, 39, 998–1000.

Fenn, M.G.P., Tew, T.E., and Macdonald, D.W. (1987). Rat movements and control on an Oxfordshire farm. Journal of Zoology, 213, 745–749.

Fenn, M.G.P. and Macdonald, D.W. (1987). The contribution of field studies to stored product rodent control. BCPC Monographs, 37, 107–113.

Brown, R.E. and Macdonald, D.W. (1985). Social Odours in Mammals. Oxford University Press, Oxford.

Macdonald, D.W. (1984). A questionnaire survey of farmers’ opinions and actions towards wildlife on farmlands. In D. Jenkins, ed. Agriculture and the Environment, Institute of Terrestrial Ecology Symposium No. 13, pp. 171–177. Institute of Terrestrial Ecology, Cambridge, UK.