Metapopulations dynamics

Wiens, J.A. 1997. Metapopulation dynamics and landscape ecology. In Metapopulation Biology (I. Hanski and M.E. Gilpin, eds), pp. 43-62. Academic Press, San Diego. 

Spromberg JA, John BM, Landis WG. 1998. Metapopulation dynamics indirect effects and multiple distinct outcomes in ecological risk assessment. Environ Toxicol Chem 17 1640-1649. 

Metapopulation dynamics is a useful tool in evaluating the consequences of stress over both time and space. A metapopulation is a "population of populations" (Levins 1970) connected through immigration and emigration. The general assumptions are that there is a minimum viable population (MVP) size below which patch extinction will occur. The carrying capacity is the... 

In conclusion, metapopulation dynamics have several important implications for predicting the impact of chemical toxicants ... 

Wu, J., J.L. Vankat, and Y. Barlas. 1993. Effects of patch connectivity and arrangement on animal metapopulation dynamics a simulation study. Ecol. Model. 65 221-254. 

SIR models typically are used to model a single population of the host species. However, metapopulation dynamics can be incorporated by linking individual colonies (each with its own SIR model) via prairie dog and flea movement parameters, /ZpD and /Zp. These parameters can themselves be functions of the landscape context surrounding individual colonies. Flea movement rates, in particular, may be enhanced in urban environments because of the increased density of domestic predators. Once the SIR models are developed, numerical simulations can be used to conduct a series of experiments that evaluate the overall risk of human infection given particular combinations of parameter values. Furthermore, by basing parameter estimates on field data, empirically based models can be developed for specific urban areas being investigated. 

Gilpin, M.E. and Hanski, I., Eds., 1991. Metapopulation Dynamics, Academic Press, London. Gotelli, N.J. and Kelley, W.G., 1993. A general model of metapopulation dynamics, Oikos... 

Keeling, M. and Gilligan. C.. 2000b, Metapopulation dynamics of bubonic plague. Nature, 407(6806), pp. 903-906. 

Spromberg et al. (1998) used a toxicant-treated metapopulation model to explore the range of possible dynamics of populations in contaminated field sites. A singlespecies metapopulation model was developed, and the distribution of the chemical was assumed to be limited to one patch and contagious within that patch. Both persistent and degradable toxicants were modeled. Five principal conclusions resulted from the simulation studies ... 

Detection of differences in metapopulation responses in impacted landscapes Population dynamics... 

The next sections discuss the potential effects of toxicants upon populations that vary in distribution in a landscape. The first part describes the types of spatial structure, and the next section discusses the use of metapopulation models in examining the potential dynamics due to toxicants. 

Classic metapopulations result from low to intermediate migration between habitat patches. Not all potential habitats necessarily contain populations. Migration between patches affects the dynamics of local populations, even including recolonization following extinction. If sufficient dispersal between patches exists, then a "rescue effect" can prevent local extinctions. Persistence of a metapopulation requires migration rates between patches, which are sufficient enough to offset local extinction rates. 

Patchy population is characterized by high rates of migration between habitat patches. Because of these high rates, the dynamics within the patch may be dominated by the migration instead of the local characteristics of the population. A characteristic of patchy populations is that one organism may spend its lifetime in several patches. In contrast, in a metapopulation the organism is likely to spend all of its lifespan within one patch. 

Metapopulation models have been used to examine the dynamics of populations resulting from pesticide application. Sherratt and Jepson (1993) have investigated the impacts of pesticides to invertebrates using single-species and a predator-prey metapopulation models. In the case of the polyphagous predator, persistence of the population in the landscape is enhanced if only a few fields are sprayed, the application rate of the pesticide is low, or the intrinsic toxicity of the pesticide is low. There also appears to be an optimal dispersal rate that maximizes the likelihood of persistence of the predator in a sprayed field. Importantly, there are also patterns of pesticide application that would cause the prey insect population to reach higher densities than would occur otherwise. Dispersal rates of the predator and the prey are important factors determining the prey population densities. The importance of dispersal in the determination of the persistence of a population in a contaminated landscape was discovered in a subsequent study. 

Hanski, L, 1997. Predictive and practical metapopulation models the incidence function approach, in Spatial Ecology The Role of Space in Population Dynamics and Interspecific Interactions, Tilman, D. and Kareiva, P., Eds., Princeton University Press, Princeton, NJ, pp. 21-45. 

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