1. Marine Mammals
An Introduction

2. Classification of a Mammal
Phylum Chordata
Class Vertebrata
Order Mammalia

3. What is a Mammal? Breathe air using lungs Endothermic Skin has hair
Maintain a steady internal temp regardless of environment
Skin has hair
Some only have hair as young
Brain is larger in relation to body size and far more complex

4. Whale with hair

5. What is a Mammal? Bear live young
Viviparous, with a few exceptions
The embryo receives nutrients and oxygen through the placenta
The newborn is fed by milk produced by the mother’s mammary glands
Produce few (but well cared for) young

7. What will we be talking about?
Order Cetecea
Suborder Mysticetes – Baleen whales
Suborder Odontocetes – Toothed whales
Dolphins, orcas, pilot whales, belugas, porpoises
Order Pinnipedia
Sea lions, seals, fur seals, and walrus
Order Carnivora
Sea otters and polar bears
Order Sirenia
Manatees and dugongs

8. Evolution of Whales/Dolphins
Whales arose around million years ago (mya) from now extinct ancient land mammals that ventured into the sea
Today’s cetaceans have vestigial hind limbs
Fossils indicate the earliest baleen whales appeared 30 mya
Most modern forms of both baleen and toothed whales appear in the fossil record 5-7 mya

9. Evolution of Pinnipeds
The earliest sea lions and fur seals appear in the fossil record about 12 mya
The earliest seals appear about mya
Ancestor fossils show that seals were once able to walk on land
The earliest walruses appear about 14 mya

10. Evolution of Sirenians
Fossil record in incomplete
Relationship between manatees and their ancestors is not known
Some evidence points to ancestral sirenians dating back to mya
Protein analysis shows that closest modern relatives are elephants and aardvarks

11. Evolution of Sea Otters
Fossil record shows the presence of freshwater otters dating back to 5-23 mya
They descended from fish-eating, otter-like ancestors about 5-7 mya

12. Evolution of Polar Bears
The oldest polar bear fossil is only 130,000 years old
Scientists believe they diverged about 200,000 years ago from an ancestral brown bear
Fun fact: Polar bears and brown bears are so closely related that they can breed and produce fertile offspring
Scientists believe evolution is taking a turn and causing convergence of these two species, not divergence

13. Grolar Bear

14. Conservation Efforts US Marine Mammal Protection Act of 1972 (MMPA)
Made it illegal to hunt or harass any marine mammal in US waters
Objective: maintain the health and stability of the marine ecosystem and to obtain and maintain an optimum sustainable population of marine mammals
Does have provisions for the following:
Allowing indigenous people to continue their traditions
Collecting animals for research and education

15. Conservation Efforts The Endangered Species Act (ESA) of 1973
Protects any species that are listed as endangered or threatened
Threatened means close to be endangered
Endangered means species is on the brink of extinction
Species are added and removed from the list often as their numbers increase or decrease

16. Conservation Efforts Marine Debris Cleanup Program
Developed by the Marine Mammal Research Program
Established to decrease the amount of marine debris in the water and on the coast

17. Conservation Efforts IUCN/The World Conservation Union
Only worldwide conservation organization
Encourages a worldwide approach to conservation
Categorizes threatened species as endangered, vulnerable, and rare
Also established a Species Survival Commission to work with zoological parks and aquariums to maintain worldwide biological diversity

18. Conservation Efforts
Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)
International treaty developed in 1973 to regulate trade in certain wildlife species
Established worldwide controls over trade for threatened and endangered species

19. Conservation Efforts International Whaling Commission (IWC)
Signed by 14 countries to regulate whaling
Purpose: manage whale stocks and protect their future
Monitors whale populations
Makes recommendations on how many whales indigenous peoples can harvest in subsistence hunting
Problems:
Only signed by 14 countries
No way to enforce the regulations