Marine Organisms

Three Categories:

• Plankton – Usually very small floating organism, either plants or animals, which are at the mercy of the tides winds and currents.• Nekton – Strong swimming animals that

live in the open ocean, not affected by tides or currents.• Benthos – Organisms that live on or in the

ocean floor, could be plants or animal

Plankton• Phytoplankton: “Plant” plankton that

photosynthesize. Often called algae.

• Zooplankton: “Animal” plankton. Eat phytoplankton

Nekton

• All animals that are capable of swimming powerfully against an ocean current

• Although many of these animals adapted to swimming great distances they usually remain close to one area because they have not adapted to environmental changes through the ocean.

Nektons

Whales

• Marine mammals that breathe air, are warm-blooded and feed milk to their young.

• Two main groups of whales:– Those with teeth – Those with baleen

Made of Keratin like your finger nails

Toothed Whales

• These include dolphins, porpoises, killer whales, belugas, and sperm whales

• Sperm whales are the largest toothed whale. They can dive to great depths (1000m) and stay under for an hour. They feed mostly on squid

Baleen Whales

• Include all the largest species of whales - blue, fin, humpback,

• They have 300-500 plates of baleen that hang from each side of the upper jaw instead of teeth, which they use to take krill out of the water

• An average humpback will eat 1-1.5 tons of krill per day

Adaptations of Whales

• Streamlined bodies• Powerful tail flukes• Thick blubber layer to keep warm• Twice as many red blood cells as other land

mammals• During dives - heart rate slows to conserve O2

• Water-tight seals on blowholes

Video: http://www.youtube.com/watch?v=UYkiRbgiwx0

Fish

• Fish are cold-blooded animals and possess gills for breathing and fins for swimming

• There are two main groups of fish:– Cartilage fish (sharks,and rays)– Bony fish (tuna, cod, halibut,)

Cartilage Fish• Cartilage fish lack bones and have a skeleton

made out of cartilage (the stuff that is in your nose)

• Cartilage fish are negatively buoyant – will sink if they stop swimming

Bony Fish• Bony fish display the greatest diversity of all

the vertebrates

• Possess air-filled swim bladders to aid in buoyancy

Benthos

• Creatures that live on, near, or in the bottom of the ocean floor.

• Some of these organisms are sponges, coral, crabs, muscles, and sea weed.

Benthos• Creatures that attach to the bottom are

barnacles, mussels, periwinkles

• Creatures that live near the bottom are crabs, lobsters, sea stars, sea urchins, and several species of fish including skates and flounder.

• Creatures that burrow in the bottom are clams and worms

CLAMS

WORMS Periwinkle

CORAL