Whales, Dolphins, Whales, Dolphins, PorpoisesPorpoises

Phylum Chordata, Class Phylum Chordata, Class mammalia, Order Cetaceamammalia, Order Cetacea

Cetaceans are grouped on basis of Cetaceans are grouped on basis of their mouths:their mouths:

Mysteceti - Whales with baleen Mysteceti - Whales with baleen (strainers) for plankton: Both (strainers) for plankton: Both nostrils have a blow holenostrils have a blow hole

Odontoceti - whales, dolphins, and Odontoceti - whales, dolphins, and porpoises with teeth; carnivores; 2 porpoises with teeth; carnivores; 2 nostrils but only one blow hole; nostrils but only one blow hole; smaller in sizesmaller in size

Marine Mammal Characteristics:Marine Mammal Characteristics:

Hair (at birth)Hair (at birth) Nurse YoungNurse Young Breathe AirBreathe Air Warm BloodedWarm Blooded PlacentaPlacenta Horizontal Tail ( All marine Horizontal Tail ( All marine

cetaceans)cetaceans)

The Blue WhaleThe Blue Whale

100 feet long100 feet long

150 tons 150 tons

The largest mammal alive.The largest mammal alive.

NarwhalNarwhal

The Tusk is an 8 foot left tooth The Tusk is an 8 foot left tooth and found only in males.and found only in males.

Beluga WhalesBeluga Whales

Pure white, Arctic whales. Called “sea Pure white, Arctic whales. Called “sea canaries” due to their vocalizations.canaries” due to their vocalizations.

DolphinsDolphins

The most intelligent whale.The most intelligent whale. Body temp is a constant 97.7 FBody temp is a constant 97.7 F Average of 7 min. between breaths.Average of 7 min. between breaths. Swims at 25 miles per hour.Swims at 25 miles per hour.

Whales and all marine Whales and all marine mammals are protected by mammals are protected by

the Marine Mammals the Marine Mammals Protection Act of 1972Protection Act of 1972..

Cetacean AdaptationsCetacean AdaptationsIn the Marine HabitatIn the Marine Habitat

SwimmingSwimming

Powerful tail flukesPowerful tail flukes

Fluke markings are Fluke markings are used as IDused as ID

Sei whales are the Sei whales are the fastest swimmers - fastest swimmers - 40 mph40 mph

DigestionDigestion

Multi-compartmentalized Multi-compartmentalized stomachs ‘chew’ food. Teeth stomachs ‘chew’ food. Teeth are conical and unspecialized.are conical and unspecialized.

DigestionDigestion Baleen Whales feed by jumping through pockets of Baleen Whales feed by jumping through pockets of

plankton (breaching)plankton (breaching)

Stomach can hold 2 tons of krill at one time.Stomach can hold 2 tons of krill at one time.

DigestionDigestion

Toothed whales often hunt in packs and Toothed whales often hunt in packs and seek out individual fish, penguins, seals, seek out individual fish, penguins, seals, sharks or other whales.sharks or other whales.

Cetacean IICetacean IIThe Journey ContinuesThe Journey Continues

CirculationCirculation

High Blood volume holds max. oxygen and High Blood volume holds max. oxygen and glucose levels. Their veins are large enough for a glucose levels. Their veins are large enough for a trout to swim through.trout to swim through.

Blood can be shunted to brain, heart , lungs and Blood can be shunted to brain, heart , lungs and muscles and away from stomach and kidneys to muscles and away from stomach and kidneys to protect vital organs.protect vital organs.

A 4 chambered heart can transfer arteriole heat to A 4 chambered heart can transfer arteriole heat to the veins as blood flows toward the tail – called the veins as blood flows toward the tail – called counter –current heat exchange.counter –current heat exchange.

Circulation Cont.Circulation Cont.

Blubber insulates against cold. Overheating Blubber insulates against cold. Overheating is solved by sending blood to surface is solved by sending blood to surface tissues ( flukes and fins) and bypassing the tissues ( flukes and fins) and bypassing the countercurrent vessels.countercurrent vessels.

Whales in captivity exercise less and often Whales in captivity exercise less and often lose the ability to cool off by straightening lose the ability to cool off by straightening the fins.the fins.

SensesSenses

Vision is poor in most speciesVision is poor in most species Vocalizations and echolocation Vocalizations and echolocation

compensates.compensates. Whales have no vocal chords but make Whales have no vocal chords but make

songs , clicks and whines by vibrations in songs , clicks and whines by vibrations in the blow hole.the blow hole.

CommunicationCommunication

Indicate territoriesIndicate territories Attract matesAttract mates Act as homing device for young.Act as homing device for young. Families of whales have their own dialect.Families of whales have their own dialect. Sounds are emitted and amplified in the Sounds are emitted and amplified in the

head through an oil filled cavity called a head through an oil filled cavity called a melon.melon.

Incoming vibrations are Incoming vibrations are focused through the jaw focused through the jaw and melon to the inner and melon to the inner ear and the brain.ear and the brain.

The sounds are extremely The sounds are extremely accurate and very loud- accurate and very loud- can be used to stun prey.can be used to stun prey.

When whales enter the When whales enter the thermocline, sounds can thermocline, sounds can be heard ¼ of the be heard ¼ of the distance around the distance around the earth.earth.

DivingDiving Lungs are completely filled and emptied Lungs are completely filled and emptied

quickly through the blow hole on top of quickly through the blow hole on top of the head.the head.

Trachea under the blow hole connects Trachea under the blow hole connects directly to lungs.directly to lungs.

Cannot breathe through their mouth and Cannot breathe through their mouth and can drown unless the top of the head is can drown unless the top of the head is exposed to air.exposed to air.

Nasal passage closes when relaxed to Nasal passage closes when relaxed to prevent water from entering the lungs, prevent water from entering the lungs, and allows them to sleep for short and allows them to sleep for short periods without drowning. periods without drowning.

Some whales go to depths of 13,000 ft. Some whales go to depths of 13,000 ft. and only breath every 90 minutes – and only breath every 90 minutes – smaller species have less range.smaller species have less range.

Oxygen is stored in the muscles. Ribs Oxygen is stored in the muscles. Ribs are collapsible to reduce internal air are collapsible to reduce internal air pockets.pockets.

ExcretoryExcretory

Specialized kidneys allow whales to drink Specialized kidneys allow whales to drink salt water. The urine is very saline.salt water. The urine is very saline.

ReproductionReproduction

Mating usually occurs in early summer.Mating usually occurs in early summer. Implantation of the egg is delayed 4 months. Implantation of the egg is delayed 4 months.

Gestation lasts 7 months, so babies are Gestation lasts 7 months, so babies are born in warm summer months.born in warm summer months.

Many whales only have one calf every 2-3 Many whales only have one calf every 2-3 years. Babies range in weight from 200 years. Babies range in weight from 200 pounds to 1 tone.pounds to 1 tone.