Exam 1 Flashcards
Goal of wildlife ecology
Seek mechanisms for the purpose of prediction
Theories
Not speculation but helps us think about a phenomenon through scientific examination
Hypothesis
Educated guess based on an observation or theory
Statistical hypothesis
Predictions. If rejected, biological hypothesis reduced in likelihood. Supported, biological hypothesis can contribute to theory
Habitat
Any area offering the resources and conditions that promote occupancy by a species
Resources
This animals need (food, water, nesting materials, etc)
Conditions
Abiotic factors off area (climate, terrain, topography, pH, etc); environmental features that are tolerable or intolerable to a species
Occupancy
Proportion of habitat units occupied
Habitat quality
Not binary; continuous variable; linked to demography, not necessarily density or vegetative characteristics; individual fitness and high growth rate=high quality
Habitat use
Often measured in relative amount of time spent in different areas within habitat; function of what animal would like to do + what it is forced to do
RUFs (resource utilization function)
Map areas of high and low use within habitat (looks like topographical map)
Confidence interval
If doesn’t overlap with 0, is significant (usually CI=95%)
Multiple regression
Multiple predictor variables; analyzes relationship between single DV and multiple IVs; used to predict value of DV
Covariate
IV that can influence outcome of analyses but is not of direct interest
Habitat selection
Effort to say something about animal preference in habitat; can infer selection or avoidance by relative availability
RSF; resource selection function
Look at patterns of animals using habitat areas more or less than what you would expect from randomization (can infer preference and avoidance)
Habitat preference
To be used carefully; selection of one habitat over another when both are equally available (hard to demonstrate in lab)
Mechanisms underlying use/selection
Ex: foraging of prey, diminishing forest (less stalking cover,etc.). Can help us understand how anthropogenic changes to landscape will impact populations
Game theory in ecology
Contingent on what other players are doing
Patches
Relatively homogeneous area within landscape that differs from its surroundings
Landscape
Composed of mosaic patches; heterogenous
Patch differentiation
Scale, species, and time dependent
Optimality theory
Make decisions based on costs and benefits
Foraging
Search for and exploitation of food resources
Foraging theory
Like consumers shopping in marketplace, foraging animals make decisions based on benefits and costs
IFD
If foragers have perfect understanding of spatial distribution of food and are free to assort themselves, then forager distribution will match that of food (equilibrium)
Isodar
If there’s an equilibrium in IFD, two patches should promote same level of fitness; isodar is the line along which the fitness of individuals in two habitats is equal
Deviations from IFD
Can occur when better competitors monopolize resources in good patch
IDD
Ideal despotic distribution; cap on good patch due to physical exclusion; socially driven by best competitors. Disproportion off fitness
Niche
Represents the range of conditions and resources within which a species can exist
Conditions
Needs, abiotic
Competition
Any use or defense of a resource that reduces availability of a resource to others
Fundamental niche
In a perfect world, where would animal live?
Realized niche
Part of n-dimensional hyperspace to which organism is restricted by other organisms or other negative interactions
Niche differentiation
Result of niche overlap, which drives divergence either immediately or long term
Intraspecific competition
Driver of individual differences
Niche Variation Hypothesis
Niche variation allows for resource partitioning within a population; reduces pressure (dolphin care study); allows for high density existence
Stable isotopic analysis
Non-invasive way to reconstruct overall diet of individual over time
