Exam 13: Population Dynamics Over Space and Time

For populations growing under the logistic growth model with delayed density dependence, which of the following combinations of parameter values is most likely to lead to damped oscillations?

Variations in birth and death rates due to random changes in environmental conditions are

A herd of 25 reindeer was introduced to St. Paul Island in 1911. The line shows the number of reindeer on the island. Which describe(s) the entire figure correctly? I. The pattern fits the exponential model of population growth. II. The population experienced an overshoot. III. The population experienced a die-off.

Which is an example of demographic stochasticity? I. increased moose mortality when the population exceeds carrying capacity II. variation in death rate of mice due to chance differences between individuals III. increases and decreases in seed production due to changes in rainfall

Under the basic model of metapopulation dynamics, when the extinction rate is equal to the colonization rate, we predict that the proportion of patches occupied $( \bar p )$ will equal

Which conclusion does the figure support?

Of the following species, which is most likely to exhibit a stable limit cycle or dampened oscillations?

Which of the following is an example of delayed density dependence? I. The per capita growth rate of a coyote population decreases as the number of coyotes increases. II. The fecundity of two-year-old frogs is based on their density as tadpoles. III. The number of seeds produced by flowers in the fall depends on the amount of rainfall the previous spring.

Consider a population with the following numbers of individuals over time. year 1: 100 Year 2: 150 Year 3: 200 Year 4: 250 If the population size in year 5 is determined by a logistic model with delayed density dependence, r = 1.1, and K = 200 individuals, what value of $\tau$ would cause the population to decrease from year 4 to year 5?

In the logistic model with delayed density dependence, an increase in the length of the time delay will affect population dynamics by

Variation in birth and death rates due to random differences among individuals is

In the logistic growth model that includes delayed density dependence, the term  indicates the

Vernal pools are ephemeral bodies of water that form in small depressions within the forested landscape during early spring in the northeastern United States (as well as elsewhere). The water in the vernal pools has its origin with winter snowmelt and spring rains. These vernal pools are important breeding grounds for some amphibian species. Describe how environmental stochasticity might influence amphibian populations at vernal pools.

There are two key predictions about how extinction probability and colonization probability affect metapopulation dynamics. List these predictions and explain how they are illustrated by this figure.

Under the basic model of metapopulation dynamics, which of the following conditions is necessary to prevent the species from going extinct?

Consider the time series of population sizes in years 1 and 2 for populations a, b, c, and d. If the population size in year 3 is determined by a logistic model with delayed density dependence from a 1-year time lag , r = 1, and K = 10 individuals, which of the following time series of population sizes would lead to an overshoot of the carrying capacity in year 3?

Population cycles I. are increases and decreases of population size occurring at regular time intervals. II. can be caused by overshooting carrying capacity and subsequent die-offs. III. indicate that a species is about to become extinct.

Which statement correctly identifies the relationship between population size and extinction risk?

Which is an example of environmental stochasticity? I. changes in the weather that increase or decrease survival by a small amount II. variation in individual health that affects likelihood of death III. forest fires that kill large numbers of individuals every 10 to 50 years

This figure shows a metapopulation for the California spotted owl. Describe two ways in which this real metapopulation differs from the assumptions of the basic model of metapopulation dynamics, $\bar { p }$ = (1 - e/c).