1. Marine Mammals: Part 3 Marine Vertebrates: Lecture 9

2. Cetacea Origins Archaeocetes (~50 mya) Pakicetus  Long, slender jaws  Simple teeth  Dorsal blowhole  Robust pelvis and hindlimbs

3. Cetacea Origins Archaeocetes (~50 mya) Basilosaurus  More obviously aquatic  Reduced hindlimbs

4. Order Cetacea Suborder Mysticeti Overview Baleen Head # of species Location/ feeding Right whale baleen; photographer unknown

5. Order Cetacea: Suborder Mysticeti Family Balaenidae Large heads Bowed (highly curved) mouth  Adaptive value?  Characteristics of baleen? Fins  No dorsal  Small pectoral fins Primarily known to feed on copepods  Feed by skimming

6. Order Cetacea: Suborder Mysticeti Family Balaenidae: bowhead whale Bowhead whale; artist unknown Arctic  Follows cycle of ice  Most northerly Mysticeti Hunting began ~1600, near extinction by 1900  Slow recovery  Inuit hunting Head may be up to 40% of body length Baleen highly valued  Silky and Long

7. Order Cetacea: Suborder Mysticeti Family Balaenidae: Southern right whale Southern right whale: Photo: Ocean Alliance Callosities Why called right whales? Two species Current status

8. Callosity close-up: Whale lice and barnacles on a right whale Whale lice Photo: Vicki Roundtree Photo: Iain Kerr Ocean Alliance

9. Order Cetacea: Suborder Mysticeti Family Eschrictiidae: Gray whales Gigi the Gray Whale Photo: Ron Church Where found? Key Features  Relatively slender  Whale lice/barnacles  Throat grooves (2-7)  Bottom feeders Method? Key food? Migration Once near extinction Recovery  Removed from U.S. endangered species list in 1994

10. Order Cetacea: Suborder Mysticeti Family Balaenopteridae Humpback Whale,Photo: K. Haberman Throat grooves: expansion during feeding Depressed frontal bones Small, posterior dorsal fin; flipper size varies Relatively fast

11. Order Cetacea: Suborder Mysticeti Family Balaenopteridae: minke whale Minke Whale, Project Atlantis Worldwide distribution To whale or not to whale? Antarctic populations feed on…krill! Northern pops feed on krill & fish

12. Order Cetacea: Suborder Mysticeti Family Balaenopteridae: humpback whale Humpback Whale Photo: H-C travel Worldwide distribution  Migrate cold water (feed) to tropics (breed)  Feed on krill and fish Huge pectoral fins Distinctive white patches Scars, barnacles and cookie-cutter bites Distinctive behaviors… Conservation status: vulnerable  Hunted by Carib natives

13. Whale songs  How produced?  Which ones sing?  Singing posture  Song length  Changes over time

14. Order Cetacea: Suborder Mysticeti Family Balaenopteridae: blue whale Blue Whale Photo: Project Atlantis

15. Blue whale facts Distribution: Once worldwide; now largest populations are off coast of _____? Migrate to tropical waters for calving  In some tropical areas, blue whales are seen year round Why might this be? Largest animal ever  Up to 24.5 meters (female); Mouth alone of 6 meters; 190 tons  Heart the size of a VW bug  Spray from blow is about 6 meters high.  Larger prior to mechanized whaling Only hunted after the development of the grenade harpoon (1800s)  In one year, 30,000 were killed (not sure which year) Loudest,deepest voice of any animal: 180 dB, 10 Hz Diet is almost exclusively…???