Chapter 4: Population Ecology Flashcards
What is carrying capacity?
The greatest density of organisms that an area can potentially support
What are some biotic factors that can impact carrying capacity?
Availability and abundance of foods, number of competitors, number of mates, number of predators, and the number and variety of disease-causing organisms
What are some abiotic factors that can impact carrying capacity?
Availability of nutrients, shelter, refuge from predators, light, water, and nesting sites
What is the equation for population growth rate?
(birthrate + immigration rate) - (death rate + emigration rate)
What is direct observation in terms of measuring populations?
A method used to measure abundance, e.g. recording sightings at particular intervals; can be time-consuming and dangerous
What are some methods of tracking animals?
Satellite, aircraft, nets, GPS, UAVs (unmanned ariel vehicles -drones)
What causes problems when directly observing population size?
It may cause undue stress or disturbance of the animals, making it unreliable, and some animals, such as birds and insects are not able to be directly observed
What is a sample in terms of calculating population size?
A small group of organisms selected from the total population; is representative of the whole population
Why is it necessary to do sampling in an unbiased/random way
You may choose a particular site because it is easy to get to or is more interesting or selecting only two sample specimens reduces the reliability greatly
What is the Lincoln index?
A formula used to estimate animal population sizes through a mark-and-recapture technique
What is the capture-mark-recapture method?
An ecological surveying technique used to measure aminal populations, in which individual animals are captured, marked, and released; after a time, the population is re-sampled and the number of marked animals caught gives an indication of population size
What is the Lincoln Index equation?
N=(Mxn)/m
Where:
N = the total population
M = the number of individuals caught, marked, and released
n = the number of individuals caught on the second sampling
m = the number of individuals recaptured that were marked
What are the three different types of distribution?
Random distribution, uniform (continuous) distributions, and clumped (grouped) distribution
What are the different types of population growth?
Exponential growth J-curve and, logistic growth S-curve
What is exponential population growth (J-curve)?
The growth of a population in an ideal limited environment. Characteristic with a J curve
