Nature of Predation Flashcards
Types of predator specializations?
Monophagous, oligophagous, polyphagous, most predators broad in prey
What must be taken into account when analysing pop dynamics?
Animals food access, not just food observed to be eating
What does prey selection depend on?
Integral part of a mixed, balanced diet
Highest nutritional value
Most sustainable to consume
Prey selection for carnivores?
Energy gained per unit of handling time and lessenging chance of damage to self
Optimal Foraging Theory
This says that traits that maximise surplus energy gained per unit time from foraging are selected or an individual
How do OFT assumptions differ with specialists/generalists?
Long tim hunting prey or not, expending energy, however giving up profit in consuming particular prey
OFT in equation form…
E/H > e/(s+h)
Derive OFT equation…
E energy content, H handling time, being diet profitability
What does OFT model indicate?
Predator should continually add less profitable items to their diet, so long as it increases overall rate of energy intake
What does OFT predict?
Inverse proprtionate relationship between handling and search times, predator being generalist when handling time short
What does switch from optimal diet occur?
When different prey occupy different microhabitats and profitabiltiy change with density
Equation for Optimal Foraging Theory…
Ei/Hi > e/(s+h)
Derive OFT equation…
E energy content, H handling time(profitability of diet
What does the OFT equation tell you?
Predator should continually add less profitable items to their diet, so long as energy intake increases
Example of feeding in presence of predators…
Barn Owl affects realised niche/foraging behaviour of heteromyid rodents, who move to microhabitats to where predators not present
