A multivariate study of the relationship between dispersal and demography in populations of Microtus ochrogaster in eastern Kansas.

M. S. Gaines, M. L. Johnson

Research output: Contribution to journalArticle

8 Scopus citations


Population density was important in explaining variation in numbers of dispersers of all age classes. Season was important for adult males and females. Dispersal was density-independent, in that a constant proportion of the population emigrated at all densities. Different demographic variables were important in explaining the rates of dispersal of each age class. Principal components analysis reduced the original set of demographic variables to 4 components. The first principal component had high positive loadings for population density variables: PC-II had high negative loadings for survival; PC-III was a reflection of seasonality, with a high positive loading for autumn; PC-IV had a high negative loading for male reproductive activity. There were statistically significant positive correlations between the factor scores of PC-II and rates of dispersal of adult males and females, and a significant negative correlation between PC-II and the rate of dispersal of juvenile males. There were significant positive correlations between PC-IV and rates of dispersal of adult males, adult females and subadult females. Except for juvenile females, number of dispersers of all age classes was correlated positively with the factor scores of PC-I. PC-II was correlated positively with the number of dispersers of both subadult males and females and number of subadult male dispersers was correlated positively with PC-III.-from Authors

Original languageEnglish (US)
Pages (from-to)223-233
Number of pages11
JournalAmerican Midland Naturalist
Issue number2
StatePublished - Jan 1 1984
Externally publishedYes


ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics

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