Marine Marine MammalsMammals

WhalesWhales

Order: CetaceaOrder: Cetacea – 90 – 90 speciesspecies

• Whales are different from seals and Whales are different from seals and sea lions because they spend their sea lions because they spend their entire lifespan in water.entire lifespan in water.

• There are two main groups of There are two main groups of whales: whales:

1. Toothed whales1. Toothed whales

2. Baleen whales2. Baleen whales

Toothed whalesToothed whales • Examples: killer whales, pilot whales, Examples: killer whales, pilot whales,

dolphins, porpoises, sperm whaledolphins, porpoises, sperm whale

• * one blowhole opening* one blowhole opening

• * eat one prey item at a * eat one prey item at a time/swallow prey wholetime/swallow prey whole

• *feed in the entire water column*feed in the entire water column

Baleen Baleen whaleswhales • Examples: gray whale, blue whale, right Examples: gray whale, blue whale, right

whales, humpback whale whales, humpback whale • 2 blowhole openings2 blowhole openings• toothless – feed with baleen which is made toothless – feed with baleen which is made

from keratin. It is a food filtering system. from keratin. It is a food filtering system. When water is pushed out of the mouth the When water is pushed out of the mouth the krill are trapped!krill are trapped!

• Keratin is the same Keratin is the same protein found in hair protein found in hair and fingernails. and fingernails. (like stiff straw)(like stiff straw)• They eat krill They eat krill (2 inches)/plankton (2 inches)/plankton • Feed at the surfaceFeed at the surface• Gulpers vs. skimmers Gulpers vs. skimmers

Comparing Toothed and Baleen Comparing Toothed and Baleen WhalesWhales

Ventral pleats – expand when water is taken into the mouth (found on baleen whales only).

MovemeMovementnt• Whales move with an up and down movement of the Whales move with an up and down movement of the

fluke (powerstroke). Upward movement provides the fluke (powerstroke). Upward movement provides the power! This is different than fish which use a side to power! This is different than fish which use a side to side motion.side motion.

• Spyhopping: vertical upward movement to look around. Spyhopping: vertical upward movement to look around. • Breaching: Jumping out of the water.Breaching: Jumping out of the water.

EcholocationEcholocation: :

• Sound travels 4X faster in water than Sound travels 4X faster in water than air. Used by whales to communicate. air. Used by whales to communicate. (we will talk about this is more detail (we will talk about this is more detail when we do notes on dolphins)when we do notes on dolphins)

DivingDiving: : To dive whales…..To dive whales…..

1. Hold breath1. Hold breath2. Rapidly exhale (90% of 2. Rapidly exhale (90% of

Oxygen exchanged Oxygen exchanged compared to 20% in compared to 20% in humans)humans)

3. Take a new breath – 3. Take a new breath – DIVE!DIVE!

– Sperm whales – 2 hour dive Sperm whales – 2 hour dive timetime

– Blue whales – 40 min dive Blue whales – 40 min dive timetime

– Bottlenose whales (dolphins) Bottlenose whales (dolphins) about 15 min.about 15 min.

Diving facts:Diving facts:• 1. Baleen whales don’t dive deep! Why?1. Baleen whales don’t dive deep! Why?• A: Because plankton/krill are found at the A: Because plankton/krill are found at the

surfacesurface• 2. Whales have more R.B.C’s than non-2. Whales have more R.B.C’s than non-

diving mammals.diving mammals.• 3. When whales dive their heart rate slows 3. When whales dive their heart rate slows

dramatically from 85 down to 12 per minute.dramatically from 85 down to 12 per minute.• 4. Blood flow to nonessential organs is 4. Blood flow to nonessential organs is

reduced.reduced.• #3 and #4 together are called #3 and #4 together are called

bradycardia.bradycardia.• 5. Nitrogen dissolves better at high pressure5. Nitrogen dissolves better at high pressure

ex. Think of the lungs like a pop bottle - ex. Think of the lungs like a pop bottle - lungs collapse – squeezes air to central part lungs collapse – squeezes air to central part of lung where little Nitrogen is absorbed. of lung where little Nitrogen is absorbed. Oxygen goes directly to blood.Oxygen goes directly to blood.