Topic 9 Flashcards
Population regulation
What are the two types of population regulation?
Density dependent regulation and density-independent regulation
What factors affect density -dependent populations?
Biotic factors such as competition and predation
What factors affect density -independent populations?
Abiotic factors such as temperature and weather
What can population growth rates be proportional to?
Population density
What are three reasons that growth rates are proportional to density?
- Competition
- disease
- Interference competition
What is the Allee effect?
small population sizes lead to low population growth due to reproductive failure
How do we find if growth is population density-dependent or not?
If birth or death rates are correlated with population density.
What does r = b-d mean?
Rate of increase is birth rates minus death rates
Define environmental stochasicity
the unpredictable fluctuation in environmental conditions
What affects mortality in sheep/deer?
Age, Climate, Density
What effects death rates in sheep/deer?
Density/Temperature
What effects birth rates in sheep/deer?
Age, Density, Year
How can we predict abundance?
N (population size)*Probability that survive + N(fecundity/adults)(prob. of survival)
What is total abundance?
It is the sum of abundance predictions?
