Population Ecology Flashcards
It uses stones to pry shellfish and break them open on their bellies while swimming on their backs.
Sea Otter
The branch of ecology that studies the structure and dynamics of populations.
Population Ecology
A group of similar individuals of the same species living in the same place at the same time.
Population
What are the four (4) major characteristics of a population?
Population size
Population Density
Population Dispersion
Age structure
What are the three characteristics of Population Dispersion?
Random Distribution
Uniform Distribution
Clumped Distribution
Number of individuals in a population at a given time
Population Size
It leads to extinction, therefore there is low chance of finding (suitable) mates, genetic consequences, environmental effects.
Very Small Populations
It leads to starvation, predation, disease which therefore there is competition in resources and etc.
Very Large populations
How many is the population in the philippines as of October 11, 2016?
102, 691, 858 Filipinos
Number of individuals of a population in a certain space at a given time.
Population Density
number of individuals per unit space
Terrestrial ecosystems
number of individuals per unit volume
Aquatic ecosystems
What are the effects of high population density
Scarcity of food
Lower access to nesting/breeding sites
Higher risk of the spread of disease and parasites
Higher susceptibilty to predation
What are the two effects of low population density
Reduced chance of finding a mate
Increased inbreeding
The spatial pattern in which members of a population are found in their habitat
Population dispersion
The position of individuals of a population are independent of the other.
Random distribution
individuals of a population are more or less evenly distributed
Uniform distribution
patches or groups of organisms scattered over a given area.
Clumped distribution
Population dispersion (and size) is also affected by…
Immigration
emigration
The influx of new individuals into a population
immigration
the dispersal of individuals from a population
emigration
distribution of organisms in a population in time
Temporal distribution
Temporal distribution maybe:
Circadian
influenced by tidal fluctuations
lunar
seasonal
due to succesional changes
due to evolutionary changes
Scientific name of sea otter
Enhydra lutris
it is the relative proportion of individuals in each age group of a population
Age structure
Age structure maybe divided into:
Pre-productive (younger than age of sexual maturity)
Reproductive (age of sexual maturity)
Post-productive (older than age of sexual maturity)
Factors that influence population size
Growth Factors (biotic potential)
Decrease factors (environmental resistance)
The number of young produced per unit of a population per unit of time; major agent of population growth.
Birth rate
The number of deaths per unit of time; major agent of population loss
Death rate
Classifications of Growth
Rapid Growth
Slow Growth
Zero Growth
Negative Growth
Younger than age of sexual maturity
Preproduction
Younger than age of sexual maturity
Preproduction
older than age of sexual maturity
Postproductive
Population size changes due to
Birth
Death
Immigration
Emigration
The capacity of a population for
growth (increase in size) →
varies among populations
Biotic potential of a population
