populations. skylark metapopulations a metapopulation is a series of small, separate populations...
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Populations
Skylark
Metapopulations
• A metapopulation is a series of small, separate populations united together by dispersal
Metapopulation DynamicsMetapopulations are viewed as sets of populations persisting in a
balance between local extinction and colonization
Metapopulations of Bay Checkerspot Butterfly
Bay Checkerspot
Jasper Ridge
Aphids and Epilobium
Habitat fragmentation in Amazonia
Demography
Demography
• Demography is the study of processes that influence population size - it is the way we study changes brought about by births, deaths and dispersal
For Northwest Montana, Greater Yellowstone, Central Idaho
The Fundamental Equation of Ecology – Harper 1977
Δ N = B – D + I – E
Change in Number = Births – Deaths + Immigration - Emigration
John L. Harper – 1925-2009
Rearrange Fundamental Equation
Δ N = B – D + I – E
Nfuture = Nnow + B – D + I – E
Often we assume that I = E,
so no net dispersal
Common Field Grasshopper
Grasshopper – development and incomplete metamorphosis
Red Deer – Stag, Hind, Fawn
Isle of Rhum, Scotland
Red deer fawnbeing taggedfor study
Arithmetic scale Logarithmic scale
General types of survivorship curves
Human management of species may change survivorship curves
A – fish mortality in typicalpopulation
B – fish takenby fishing
PopulationPyramidFor FranceJan. 1, 1967
Changes in population of Japan over time
Changes in population of Canada from 1971-2006