Transcript Feeding Interactions - Mr. Kozel's BHS Biology

Food Webs and
Pyramids
Feeding Interactions Terms
• Autotroph(Producers) - Plants, produce
energy from the sun. How?
• Heterotroph(Consumers) - obtain energy
from consuming (eating)
• Herbivores - consumers that only eat
plants
• Predators - eat other animals
• Carnivores - meat only
• Omnivores - meat and plants
• Decomposers – organisms that obtain energy
from dead organic material, return organic
material to the abiotic ecosystem
• Bacteria
• Fungi, slime molds
Photosynthesis
Food Chain
• Shows energy movement through a single feeding
interaction in an Ecosystem.
• Arrows represent energy movement
Grass
Producer
Grasshopper
Frog
Snake
Red tailed Hawk
Primary
Consumer
Secondary
Consumer
Tertiary
Consumer
Top-level
Consumer
Herbivore
Predator
Predator
Predator
Food Web
•Shows all the feeding relationships in an community.
•Arrows show the movement of energy
Trophic Levels
Grass
Grasshopper
Producer
Primary
Consumer
Frog
Snake
Secondary
Consumer
• Trophic levels in a food chain
Red tailed Hawk
Tertiary
Consumer
Top-level
Consumer
• Producer, Primary Consumer, Secondary
Consumer, Tertiary Consumer, Top-level
Consumer
-or• Producer, 1st level consumer, 2nd level consumer,
3rd level consumer, top-level consumer
Trophic Levels – Food Web
• Organisms can play multiple roles in an ecosystem
• Ex. The Bat is both a primary consumer and a
secondary consumer
What is Biomass?
• Total dry mass of all the living material in an ecosystem.
• Used to quantify the biotic components of an ecosystem
Ecological Pyramids
• Diagrams that display a feeding relationship in an ecosystem
and another aspect of that feeding relationship, such as…
• Energy at each trophic level
• Biomass at each trophic level
• Population at each trophic level
Energy Pyramid
• Diagram showing a feeding relationship and the total energy
at each trophic level.
• Energy measured in kJ, J, or cal.
• 10% rule – approximately 10% of energy contained in a trophic
level is available to the next trophic level (90% is “used”)
Biomass Pyramid
• Shows the consumable Biomass for each trophic level.
Pyramid of numbers
• Shows the population of each trophic level
Lab 2-3: Owl Pellets
• Calculate a pyramid of numbers and biomass pyramid for the
barred owl based on observations from its pellets
Owl-Pellet Pyramid of
Numbers
Consumption for 1 owl for 1 year
Predator
Top-level
consumer
1
Owl
2000-4000
Prey (mice,
shrew, moles,
birds)
#? Producers (Plants)
Prey
Herbivores
(mostly)
Primary
Consumers
Owl-Pellet Biomass Pyramid
Consumption for 1 owl for 1 year
Top-level
Consumer
Primary
Consumers
.8 Kg
Owl
80 kg Mice,
Shrews, Moles,
Birds
Producers
3,648 kg Plants,
seeds, nuts,
grains…