Upgrade to remove ads
Biotic Factors Affecting Mammal Populaitons
Terms in this set (40)
Population growth causes?
An increase in density causes competition for? (2)
What does a competition for space cause?
What does competition for food cause?
Changing vital rates (fertility, survival, dispersal) as density changes
Any environmental factor whose effect on the vital rate of changes with density
Is detecting density dependence easy or difficult?
_________ out of 19 surveyed mammal species exhibit density-dependent population growth. With the exception of _____________.
Larger mammals are ___________ from the abiotic environment more than small mammals. Thus expect larger mammals to be affected by density dependence ___________ frequently.
Survey found evidence of __________________ _________________ in 45 species of large mammals (principally ungulates, cetaceans, and marine carnivores)
-Any environmental factor quantifiable by affecting population growth.
-Both biotic and abiotic factors
What are some examples of limiting factors? (DD or DI)
Hurricane, drought, freezing rain, influx of predators, outbreak of disease.
Regulating factors (DD)
-Density-dependent factors that keep populations within normal range (depress growth as N increases)
What are some examples of regulating factors?
Logistic growth is the per capita growth rate _____________ linearly from r(m) when N= ____________ to 0 when _________.
declines, zero, N=K
What does a growth rate of 0 mean?
population N doesn't change
Logistic growth has a ________________ or ______ shaped curve. Where growth rate is ________ to density.
sigmoidal, S, tied
What is intra-specific competition?
Competition within a species
What are the two proximate causes of intraspecific competition?
Mammalian competition usually focuses on ____________ or _____________. If the resource limiting population growth is food than the addition of food should ______________ ____________, _________________ ________________, ___________ ___________________.
food, space, enhance fertility, reduce mortality, grow populations.
What happened when food was added to an experiment of 23 species of mammals, generally? (5)
-Home-range size declined
-Home-range overlap increased
-The breeding season was lengthened
-Litter sizes increased in poor habitiat
-Population density increased 2-3 fold
Supplementation suggests ____________ is limiting for many mammals. However, supplemented populations follow same __________ or _____________ trends suggesting _______________ does not regulate populations. (AKA after __________ other factors may limit density)
food, annual, multiannual, food, doubling
Amount of space needed by an individual animal
Food may limit density after doubling because of _________________ not _____________. Changes in density primarily due to ___________________.
accessibility, availability, immigration
At high densities mammals may ______________ a resource. (e.g. ____________ _______________) high __________ densities = severe _____________ _____________.
decimate, voles, deer, deer, vegetative degradation
Measure of deer body condition (fat reserves)
What are the two ways to measure the wellbeing of an animal?
-Body weight/kidney fat
High deer density sites with ___________ _________________ should contain deer in __________ condition. Observe expected relationship between deer condition and deer density if _______________ is limiting.
degraded vegetation, poor, food
Territory ownership can mean ______________ _____________ (e.g. ___________ &___________).
breeding rites, voles, cats
Increasing density ___________________ intruder pressure, which can cause ________ ____________ and ___________ ____________ _________________
increases, increased strife, reduced reproductive output
______________ ____________ example of banner-tailed kangaroo rats.
Mounds can are essential to survival because?
Are mounds expensive or inexpensive to build?
Vacant mounds are _____________ at high densities.
What is predicted at high densities?
-Lower survival rate of dispersers
-Non-dispersers survive better
-advantage of philopatry greatest for females
_____________ mammals often most severely impacted by density dependent competitive effects. __________ ________ juvenile mortality in summer and fall is ____________ influenced by abundance of adults.
Juvenile, snowshoe hare, positively
Adult survival is generally sensitive or less sensitive to biotic and abiotic factors?
Density dependent survival has been demonstrated for adult for several mammals mostly __________. Best data from _________.
Numerous mammals exhibit ___________ ______________ changes in fertility. These repsones are often _____________________- with reproduction dropping off sharply at high densities this pattern is called _____________.
density dependent, non-linear, inversity
OTHER SETS BY THIS CREATOR
Full Bird Exam
Birds Quiz #2
OTHER QUIZLET SETS
honors world history test #4
PHF 155- Ch. 5 Adaptations to Anaerobic Training P…
chapter thirty-three: protostomes
ED-PUZZLE: The US Constitution