Transcript Food Chains and Food Webs

Food Chains
and Food Webs
What is a food chain?
• A food chain is “a sequence of organisms,
each of which uses the next, lower member of
the sequence as a food source1”
Let’s Look
at a
Food Chain
• A food chain is a
simplified way to
look at the energy
that passes from
producers to
consumers.
Important facts about food chains
• In a food chain each organism obtains energy
from the one at the level below.
• Plants are called producers because they
create their own food through
photosynthesis3
• Animals are consumers because they cannot
create their own food, they must eat plants or
other animals to get the energy that they
need.
Producers
• Producers make their
own food
• Green plants use
energy from the sun
to make food
• Producers are on the
bottom of the food
chain
Primary Producers
• Primary producers are “organisms capable of
producing their own food4”
• We can also say that they are photosynthetic, use
light energy.
• Examples of primary producers include algae,
phytoplankton, and large plants.
• Primary producers are eaten by primary consumers
(herbivores)
Primary Producers of NJ Marshes
Marsh Mallow
Cattails
http://www.nicerweb.com/doc/class/pix/PRAIRIE/2005_07_18/Typha_angustifolia.jpg
http://www.ncdot.org/doh/Operations/dp_chief_eng/roadside/wildflowerbook/graphics/images/page14a.jpg
Marsh Fern
Blue Flag Iris
http://www.ontariowildflower.com/images/blueflag2.jpg
http://wisplants.uwsp.edu/scripts/detail.asp?SpCode=THEPALvPUB
Consumers
• Consumers hunt, gather, and store
food because they cannot make
their own.
Four types of consumers
• Herbivores: animals that eat only plants3
• Carnivores: animals that eat only other
animals3.
• Omnivores: animals that eat animals and
plants3.
• Detritivores: Animals that eat dead materials
and organic wastes
Other Ways to Classify Consumers
1. Primary Consumers: Herbivores3.
2. Secondary Consumers: Carnivores that eat
herbivores3.
3. Tertiary Consumers: Carnivores that eat
other carnivores3.
Herbivores
• Animals who eat plants such as:
–grasshoppers
–rabbits
–squirrels
–deer
–pandas
Carnivores
• Animals who only eat other animals
such as:
–tigers
–lions
–hawks
–wolves
–cougars
Omnivores
• Animals who eat both plants and
animals such as:
–humans
–bears
Primary Consumers in Marshes
Muskrat (eats mostly Cattails)
http://wdfw.wa.gov/wlm/living/graphics/muskrat1.jpg
http://www.advancedwildlifecontrolllc.com/images/muskrat.jpg
Primary Consumers in Marshes
• Wood Duck eats seeds like those of the
Swamp Marsh Mallow and Blue Flag Iris
http://dsf.chesco.org/ccparks/lib/ccparks/wood_duck_pair.jpg
Primary Consumers in Marshes
• Glassy-winged Toothpick Grasshopper – eats
leaves of plants like cattail and pickerelweed
http://bugguide.net/node/view/41662
Secondary Consumers
• Black Rat Snake eats eggs of animals like wood
duck
http://www.bio.davidson.edu/projects/tate/Terms.htm
Secondary Consumers
• Swamp Sparrow eats seeds but also insects
like the toothpick grasshopper
http://www.jeaniron.ca/2007/SwampSparrow6645.jpg
Tertiary Consumers
• Eat other animals in marsh including snake
and sparrow
Osprey
www.montereybay.com
www.audubon.org
Omnivore
• Racoon eats seeds, fruits, insects, worms, fish,
and frogs… and pretty much anything else
they can get their paws on!
http://abouttitusville.com/BobPaty/Animals/images/Racoon.jpg
Detritivore
• Worms are common detritivores in many
ecosystems including marshes
Decomposers
• Microorganisms that are able to
break down large molecules into
smaller parts
• Decomposers return the nutrients
that are in a living thing to the soil
What is a food web?
A food web is “an interlocking pattern of food
chains2”
What is a Food Web?
• A more realistic way of looking at
the relationship of plants and
animals in an environment
• Several food chains linked together
• A predator from one food chain
may be linked to the prey of
another food chain
Food Webs
• How many food chains can you make
from this food web?