Marine Food Web

sunlight

phytoplankton

                        

zooplankton

carnivores

                                              

benthic & pelagic suspension feeders

                                               

                                                      

                                                      

other carnivores

other carnivores

Arrows show flow of energy and materials.

What is plankton?

• Comes from the Greek word “to roam”

• Cannot swim against ocean currents.

• Can move their limbs but their overall position or location is determined by water currents

Where are they?

• Pelagic division– Open water at all depths

• Transparent• Constantly moving

• Photic zone – Light penetrates 100 meters

Phyto- or Zooplankton?

Phytoplankton Zooplankton

Dinoflagellates

Diatoms

Adaptations

Adaptation Reasoning

Small Requires less food

Transparent Camouflage

Spiny extensions

Protection and prevent sinking

Oils Buoyancy

Large eyes Sight

Transparency

Spiny extensions

Large eyes

Phytoplankton

• Photosynthetic autotrophs– Diatoms– Dinoflagellates– Bacteria

Diatoms

• Greek Dia = across and tom = to cut

• Enclosed with 2 silicone shells

• May produce oil for buoyancy

• Can cause shellfish poisoning

Impact

• May turn water green

Dinoflagellates

• Greek Dinos = rotating and flagellate = flagella

• Red or brown accessory pigments

• external armored plates of cellulose

• motile by means of flagella

• Non-motile symbiotic zooxanthellae stage found in corals

Impact• Toxic

– Saxitoxins=paralytic shellfish poisoning (PSP)– Brevitoxins=neurotoxic shellfish poisoning (NSP) – Pfiesteria – red tide

Bioluminescent

• Special bacteria

Dinoflagellates

Zooplankton

• Planktonic heterotrophic organisms– Animals

• Larval stages• Copepods

– Protozoans

Where do they go?

• Holoplankton– Permanent plankton

• krill, copepods, jellyfish

• Meroplankton– Temporary plankton

• Sea urchin, starfish, crab, lobster, octopus