Deposit Feeding

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Deposit Feeding

• feeding mechanism where an organism gets its food
  and nutrients from soft-bottom sediments.
• There are two types of deposit-feeding
• 1) Direct
• 2) Selective

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What Types of Invertebrates Use This Type of
Feeding Mechanism?
Fiddler Crabs
Sea Cucumber
Earthworms
http//www.fiddlercrab.info/
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- What are some advantages and disadvantages of
deposit feeding?
- What types of environments are ideal for
invertebrates that use this feeding mechanism?
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Chemoautotrophy

• - When prokaryotes live symbiotically in the
  tissues of invertebrates (usually marine)

- Use CO2 and their carbon source
- Obtain energy by oxidizing H2S NH3, CH4 and
Fe2.
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Advantages and Disadvantages
Advantages - Inverts have the bacteria produce
all the energy for them - In symbiotic
relationships, neither organism is harmed
Disadvantages - Must live in a place where
these sulfides are in abundance (hot water vents
and deep sea floors) - Must use reduced forms of
the compounds needed
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Invertebrates that use Chemoautotrophy
- Some Mussels and Clams
- Vestimentiferan Tubeworms
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Predation

• What is It?

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• The active capture of live animals
• Involves the finding of prey, pursuit, capture,
  handling, and ingestion
• 4 kinds stalkers, lurking predators (ambushers),
  sessile opportunists, and grazers

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Scavenging

• What is it?

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• Moving across the bottom and picking up food
• Includes predatory grazers
• Example would be snails crawling along and
  nipping off polyps as they go

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Two Examples

• Octopuses
• Trilobites

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Octopuses
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What Octupuses Eat

• Crustaceans (mostly crabs)
• Some bivalves

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How They Catch Their Prey

• Speculative pounce and groping methods
• They explore the surfaces of rocks, clumps of
  algae and/or the seabed
• Usually involves manipulation of the prey
• They will camouflage themselves with their
  surroundings, wait for the unsuspecting critter
  to go by, and then pounce on it

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How They Eat Their Prey

• Drill a hole- occurs by the combined action of
  the radula and salivary papilla
• Salivary glands produce chemicals and enzymes to
  weaken shell
• Once the hole is completed, octopus injects a
  paralyzing toxic agent that induces muscle
  relaxation of the prey
• When the prey is paralyzed, the octopus ingests
  it
• When eating bivalves, they drill the hole and
  inject the toxin, and after the critter is
  paralyzed, they pull the valves apart and ingest
  it