Estimating the parameters of survival and migration of individuals in metapopulations

Ecologists working with metapopulations are interested in the rate of migra tion among several local populations, mortality during migration, and the s caling of migration rate with habitat patch area and isolation. We describe a model of individual capture histories obtained from multisite mark-relea se-recapture studies, which allows one to measure these parameters using ma ximum likelihood estimation. The model yields separate estimates of mortali ty within habitat patches and mortality during migration, on the assumption that only the latter is affected by the isolation of the source population . The model is suitable for studies involving 10 or more populations, with differences in habitat patch areas and isolation, and in which several hund red individuals have been marked and recaptured. We apply the model to a me tapopulation of the butterfly Melitaea diamina with 14 local populations, 5 57 marked individuals, and 1301 recaptures. Immigration and emigration scal ed as patch area to power 0.2, Roughly half of the daily losses of individu als from habitat patches of 1 ha in area were due to emigration, <1% of dai ly migration distances were >1 km, and 16% of all deaths were estimated to have occurred during migration. Programs are available to calculate the par ameter estimates, their confidence intervals, and goodness-of-fit tests.