The Ocean

1
The Ocean

• SeaWorld San Diego Education Conservation
  Department

2
Introduction

• The ocean is a body of saltwater that covers 71
  of Earths surface.
• It contains 97 of Earths water. The other 3 is
  divided into freshwater (1) and water that is
  frozen in glaciers and the ice-caps (2 to 3).

3
One ocean or many?

• The ocean is divided into geographical regions.
  However these regions are all connected, forming
  one global ocean.
• There are 5 geographical oceans the Atlantic,
  Pacific, Indian, Arctic, and Southern oceans.

4
The Atlantic Ocean

• The 2nd largest ocean region (about ½ as large as
  the Pacific Ocean) containing about 25 of
  Earths water area.
• Includes the Mediterranean Sea, Gulf of Mexico,
  Caribbean Sea, Baltic Sea, and Hudson Bay.
• Deepest point the Puerto Rico Trench 8,605 m
  (28,231 ft.).
• Contains an underwater mountain range called the
  Mid-Atlantic Ridge, which is Earths longest
  mountain range (extends from the edge of the
  Arctic to the center of the Southern Ocean.

5
The Pacific Ocean

• The largest ocean region containing about 46 of
  Earths water area. About 15 times the size of
  the United States.
• Deepest point (in the Pacific Ocean and on Earth)
  Challenger Deep in the Mariana Trench 10,920 m
  (35,827 ft.).
• Contains more than 25,000 islands.
• Home to the Great Barrier Reef (Australia) the
  largest coral reef expanse on Earth (2,300 km
  (1,429 mi.)).

6
The Indian Ocean

• The 3rd largest ocean region, containing 20 of
  Earths water area.
• Deepest point the Java Trench 7,449 m (24,441
  ft.).
• Contains the saltiest sea the Red Sea and the
  warmest sea the Persian Gulf (about 35C
  (95F)).
• Warm, tropical waters allow a rich variety of
  marine life to live in this ocean. About 4,000
  fish species live near the shores, many which are
  only found in this ocean.

7
The Arctic Ocean

• Smallest and shallowest of the 5 ocean regions.
• Contains 3 of Earths water area.
• Produces up to 50,000 icebergs each year.
• Deepest point Molloy Deep 5,669 m (18,599 ft).
• Almost completely surrounded by land with Europe,
  Asia, North America, and Greenland
• Connected to the Pacific Ocean through the Bering
  Strait.
• Covered by an icepack year-round (with an average
  thickness of 2 m (6.56 ft.)). This icepack
  extends around the edges during winter and
  dwindles by 50 in the warmer months.

8
The Southern Ocean

• Contains 6.5 of Earths water area.
• Deepest point South Sandwich Trench, 7,412 m
  (24,317 ft.).
• Previously known as the Antarctic Ocean. Renamed
  in the year 2000.
• Not defined by land boundaries 60S latitude
  marks the northern boundary. This is a natural
  boundary where cold polar currents collide with
  warmer waters of the oceans to the north (The
  Antarctic Convergence).

9
Ocean Life

• About 250,000 marine species have been discovered
  (of about 1.5 species worldwide).
• Any animal that depends on the ocean for survival
  is considered a marine animal.
• The following slides show examples of marine
  animals and plants

10
Marine Invertebrates
Invertebrates are animals without backbones.
About 146,000 species of marine invertebrates are
known. Scientists believe there are thousands
more to be discovered.
giant clam
giant Pacific octopus
tube-dwelling anemone
moon jellyfish
California spiny lobster
sand rose anemone
hermit crab
cuttlefish
chambered nautilus
skunk cleaner shrimp
flower leather coral
rainbow sea star
11
Marine Reptiles
Reptiles are air-breathing, cold-blooded animals
that have scales and lay eggs. Some reptile
species live in the ocean including sea turtles
(8 species), sea snakes (80 species), several
crocodile species, and a marine iguana species.
12
Marine Birds
Marine birds (or seabirds) are birds that depend
on the ocean for survival. Some, like penguins,
can swim to get food. Others, like pelicans, can
scoop their prey from just below the waters
surface. There are about 300 seabird species
worldwide.
puffins
Humboldt penguin
pelican
13
Fishes
Fish are cold-blooded vertebrates that obtain
oxygen from water using gills. They also have
scales and most lay eggs. Fish are divided into 2
categories
bony fishes Over 55 of fish species worldwide
are found in the ocean (about 17,000 species).
Bony fishes are those that have a skeleton
composed of bone. They are found in tropical,
temperate, and polar seas.
cartilaginous fishes Cartilaginous fishes have a
skeleton made of cartilage. Sharks (more than 400
species) and batoids (about 500 species of rays
and skates) are cartilaginous fishes. They are
found in tropical and temperate waters and some
in cold and polar seas.
14
Marine Mammals
Marine mammals are warm-blooded, air-breathing
vertebrates that have fur and give live birth to
young. Many spend their entire lives in the ocean
and some are able to come ashore to rest and
breed. Marine mammals include Cetaceans (whales,
dolphins, porpoises about 83 species),
Pinnipeds (seals, sea lions, walruses about 30
species), Sirenians (manatees and dugongs 4
species), otters (2 species), and polar bears (1
species).
polar bear
killer whale
manatee
California sea lion
beluga whale
Commersons dolphin
sea otter
walrus
gray whale
harbor seal
15
Marine Plants Algae
Marine plants include about 60 flowering species
known as sea grasses that occur underwater. Some
ferns, shrubs, and marsh grasses grow near the
shore or in brackish water.
Red, green, and brown algae are also known as
seaweeds. They occur in most ocean habitats
from tide pools to kelp forests.
16
Microscopic Marine Life

• Plankton is tiny single or multi-cellular
• organisms which float through the water.
• phytoplankton microscopic floating plants and
  algae. Forms the base of many ocean food webs.
• zooplankton microscopic floating animals,
  including animal larvae.
• bacteria

17
How we use the ocean

• food various fishes, shellfish, lobster, crab,
  shrimp, octopus, squid
• recreation watersports, fishing, surfing,
  snorkeling, whale watching, tide pooling
• travel shipping routes
• resources oil natural gas extraction,
  minerals, biochemicals

18
Threats to the ocean

• Humans have used the ocean for thousand of years
  for food,
• recreation, and travel. However, with an
  increasing world population
• the ocean is under intense pressure from human
  activities. Threats to
• the ocean include
• pollution
• As water moves to the ocean through watersheds,
  it often picks up different forms of pollution
  such as oil, bacteria, trash, or pesticides from
  urban and agricultural areas. Once this polluted
  runoff reaches the ocean, it can harm the plants
  and animals that depend upon clean water to
  survive.
• Trash can end up in the ocean from land through
  storm drains, sewer systems, streams, and rivers.
  Boats and fisherman often discard trash and used
  fishing gear. People using beaches leave trash
  directly near the ocean. This debris can harm
  plants, animals, and even humans who visit
  beaches.

19
Threats to the ocean

• overfishing
• With more mouths to feed throughout the world,
  more and more food is taken from the oceans.
  Unfortunately, some have taken too much and
  certain fish (and shellfish) populations cannot
  recover. When one species has been exploited,
  fishing industries turn to another, repeating
  this overfishing cycle. Depleting one population
  can affect food chains and other marine
  populations, throwing off natural ecosystems and
  processes.
• habitat destruction
• Many key marine habitats have been destroyed by
  human activities, making them uninhabitable for
  many marine species. Destructive human activities
  include careless boating and recreation,
  overharvesting of key species, and destructive
  fishing practices (dynamite fishing and bottom
  trawling). Habitats are also disappearing due to
  building and land development.

20
Threats to the ocean

• global climate change
• Rising average temperatures have already led to
  shrinking of glaciers, later freezing and earlier
  thawing of sea ice, and shifts in distribution of
  species and their prey.
• If ocean temperatures or salinity significantly
  change, the system of interconnected ocean
  currents that create the planets climate could
  shut down.
• Excess amounts of carbon dioxide in the ocean
  increases ocean acidification, which can dissolve
  organisms with calcium carbonate based skeletons
  (ex corals, molluscs, and many zooplankton
  species).
• Other changes include sea level rise, land loss
  (ex wetlands and mangroves), increased flooding,
  and an increase in severe weather events.

21
How can you help?

• Help keep the ocean clean! Make sure your trash
  always reaches a trash can or recycling bin.
  Participate in a beach or nearby habitat
  clean-up. You will help prevent debris from
  entering waterways and other habitats and keep
  many animals safe.
• If you eat seafood or someone in your family
  does, make sure it is sustainable meaning the
  fish was caught without damaging wild fish
  populations.
• Reduce your energy impact. Turn lights off when
  leaving a room and make sure others remember to
  do so. Unplug appliances when not in use (cell
  phone chargers, video games, music players).
• Dont pour it down the drain! Encourage others to
  properly dispose of household chemicals such as
  pesticides, cleaning solutions, oil, grease, and
  paint.
• Many household cleaning products are green and
  do not have harmful chemicals in them. Also, many
  cleaning products can be made of natural
  ingredients you may have at home. Research with
  your family ways to make environmentally safe
  cleaning products.

22
How can you help?

• Encourage your family and friends to drive less
  and walk or ride bikes together instead. Start a
  carpool to school or sports practice with
  classmates and teammates. This will not only save
  Mom and Dad money on gas, it will also reduce the
  amount of carbon dioxide being released into our
  atmosphere.
• Be water wise! Every living thing needs water,
  and it is in high demand. Whether washing a car,
  your dog, or your dishes, use less and use
  wisely. Politely remind your family members and
  friends to do the same.
• Keep learning! The more we know about our world,
  the more we can do to help habitats and animals
  in need. Learn by reading books or visiting
  websites, visiting a zoo, or exploring your own
  neighborhood habitats. Share what you have
  discovered with friends and family.