Presentation on theme: "Functional Response Lab 10 Turn in proposals on front table."— Presentation transcript:
Functional Response Lab 10 Turn in proposals on front table.
Today’s Objectives Understand functional response of a predator at varying prey densities Understand what contributes to the three different types of functional response curves
Optimal Foraging Theory Foraging is a trade-off between energy costs and gains Accounting for: –Search time –Handling time –Energy gained
Optimal Prey Size Handling time Very highmediumlow Energy Gained highmediumVery low
Predator/Prey Interactions Changes in # of predators in response to # of prey Changes in predator’s rate of consumption based on prey density
Functional Response Curves A single predator’s consumption rate of prey In relation to the prey population There are 3 general classes of functional response ( I, II, III)
Type I Linear increase in consumption Little to no handling time
Type II Typical of predators that specialize on one or a few prey species
Type III Prey refugia Low density Learning –Search image –Where to find prey Prey Switching
Prey density effects on predator consumption rate >> Part 1: No handling time << You will be the predators. Black-eyed peas are the prey. See directions in handout/coursepack.
Prey density effects on predator consumption rate >> Part 2: Handling time << - You are the predators - Rocks are the prey - Handling time is affected by your capturing tools (chopsticks) 1) Make predictions (on handout) 2) Capture prey at each density. Time limit=30 sec 3) Record handling time by stopping timer when all prey have been captured (up to 30 sec)
Prey density effects on predator consumption rate >> Part 3: Refugia << You are the predators Glass beads are the prey Handling time is affected by your capturing tools (spoons) 1) Make predictions (on handout) 2) Capture prey at each density (move around room to each density). Time limit=30 sec
Announcements Read Lab 2: Estimating Populations pgs (different from what’s on syllabus)