Summary
The current longterm study on amphibian populations
and landscape ecology is located in the area of Bonn
(Northrhine Westfalia, Germany) in a typical european
agricultural landscape. It continues two previous studies
starting in 1988 and 1993. The main subject of this
longterm investigation is the development of amphibian
populations in natural and artificial ponds. The combination
of capturing and marking animals in the field, genetical
methods (enzyme electrophoresis) and analysis of important
population parameters like age structure (skeleton chronology)
and reproductive success make it possible to estimate
the stability of populations of the species examined
(Smooth Newt, Alpine Newt, Crested Newt, Common Frog,
Agile Frog, Marsh Frog, Pool Frog, Edible Frog and Common
Toad). This data are used for analysis of migration
rates and isolation of subpopulations and modelling
of population size and species composition. Additional
information on environmental factors like land use,
microclimate, water chemistry and waterlevel dynamics
of ponds can help to understand the dynamics in species
composition and dominance.
These longterm observations and analysis of factors
mentioned above can help to work out the key factors
for sustainable, more or less species rich population
of amphibians in agricultural landscape.
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