Population ecology [final]

Water lillies in a particular lake are an example of what kind of group?

population

Wolves at yellowstone park are an example of what kind of group?

population

Factors like weather + climate, physical barriers, ect. that limit populations?

range

One of the most key features defining a population?

geographic range

Devil’s hole pupfish living in a single spring in southern Nevada is an example of what?

range

What ways is demography a useful tool for ecology? (4 things its used to evaluate)

birth rates

death rates

age distributions

pop size

Study of how deaths + births change populations over time?

demography

What two categories can demographics of a population be divided into?

• dynamics

• structure

What aspect of demography involves the actual change of a population through time resulting from birth, death + migration?

dynamics

What aspect of demography is regarding density, proportions of individuals in age classes, spacing, ect?

structure

Number of organisms in a given unit area

density

What population variable is used in determining the rarity of a population or recovery after a serious threat?

density

Population growth heavily affects population _____

density

Knowledge of density + population growth can help make decisions to ________ species

manage

What are the three methods to quantifying population density?

• visual count

• sampling + extrapolating data

• mark-recapture

What method would be used to quantify population density of birds?

mark-recapture

What method would be used to quantify the population of plants, fungi, barnacles, easily-identified, slow moving taxa?

visual count

What method would be used to quantify population density of elusive microorganisms + plankton?

sampling methods + extrapolation

What does a mark-recapture survey entail?

• capturing a subset of an area + marking them

• repeating cycle over period of time to understand how many there are

Elusive animals like birds would best be quantified using what strategy?

many visual tactics

What is a uniform distribution pattern usually an indication of?

competition

Equally spaced pattern of organisms is known as what?

uniform distribution

What is the most common dispersion pattern?

clumped

What is the most rare distribution pattern?

random

Random dispersion pattern may occur where the state of resources is?

common + abundant + equally distributed

To combat the issue of patchiness of clumped dispersion, what do ecologists refer to for an accurate read?

ecological density

Offspring produced in a single reproductive event, individuals reproduce once + die

semelparity

A reproductive in successive years or breeding seasons

iteroparity

What are the two types of iteroparity?

seasonal

continuous

Continuous iteroparity is commonly due to availability of?

resources year round

reproductive strategies have a strong effect on ___ _______ of a population

age classes

What kind of age classes are typically found in semelparous organisms?

same-aged/cohorts

What kind of age classes are typically found in iteroparous organisms?

different ages

We’d expect a population that is increasing in size to have ____ young, and a population that is decreasing to have _____ young

many

few

An undisturbed forest would result in what age classes dominating?

more young

An overgrazed forest would result in what age classes dominating?

more old

Data complied on the # of individuals alive in a particular age class

life table

What variable is usually not included/collected for life tables?

males

Life tables gather data about # of organisms alive at the start of a year, and # of organisms dying during that year to calculate what?

proportion alive

What are life tables used to calculate?

contribution of age groups to reproductive rate

net reproductive rate

Typically, when do the highest death rates occur in the life cycle?

younger

What does type I of survivorship curves include?

number of survivors remains stagnant til old age, then significant dop

What does type II survivalship curve include?

consistent relationship between rate of decline + age

What type of survivalship usually means threats to the organims remain relatively the same from young → old?

type II

What does type III survivalship curve include?

largest survivor decline occurs when young

Organisms who produce LOTS of offspring would usually fall into what type of survivalship curve?

III

When looking at life tables, the age specific fertility rate is really equal to the proportion of what?

female offspring born to females

What variable is used to show age-specific fertility rate?

m(x)

What variable is used to show age-specific survivorship rate?

L(x)

The net reproductive rate is the sum of?

age survival x age fertility

Net reproductive rate is used to determine what two data points?

• growth rate per generation

• # offspring born to females of all ages

To calculate future population size what two variables do you multiply?

current pop size X reproductive rate

Nt+1 is the variable for what?

future population size

if R0 is greater than one, what is happening to the population?

growing

if R0 is less than one, what is happening to the population?

declining

if R0 is equal to one, what is happening to the population?

equilibrium

The exponential growth curve is shown when resources are?

abundant

The logistic growth curve is shown when resources are?

limited

What two models are used to show insight to shorter time period of growth?

exponential + logistic

On a population size graph, K is known as?

carrying capacity

In a population size graph, if net reproduction rate + overall population are both increasing, what graph is shown?

exponential

What population size graph account for carrying capacity?

logistic

Factor that is known as growth rate in formula?

r

Type of species with high rate of per capita population growth, but poor competitive ability

r-selected species

Opportunists are what kind of species?

r-selected

Type of species with more stable populations, exist near carrying capacity?

k-selected species

What species are known as competitors?

k-selected

Type of species that has lower reproductive rates but better competitors, also prone to extinction?

k-selected species

What selected species type will have a much longer recovery rate for population?

k-selected

A frog putting out a ton of potential eggs, what kind of strategist is it?

r-strategist

A lizard putting out 2 eggs + being highly invested in their growth is what kinda strategist?

k-strategist