Seabirds

SeabirdsA. Diversity:

2. Diet• Small zooplankton – Prions

• Fishes – Penguins

• Squids – Petrels

• Benthic invertebrates – Razorbill

• Other birds – Petrels

• Resource partitioning is common (minimizes competition)

SeabirdsA. Diversity:

3. Geographic Range• Stay in same region or travel thousands of kilometers

B. Beak Shape

SeabirdsC. Prey Capture

pelican

Marine MammalsA. General Characteristics

Marine MammalsA. General Characteristics

• Endotherms and homeotherms

• Hair

• Viviparous• Placenta

• Mammary glands

• Have few young

• Large and complex brain

Marine MammalsB. Order Pinnipedia

• Evolved from terrestrial carnivores• Predators - Fishes, squids• Streamlined bodies• Blubber layer under skin• Inhibit loss of body heat through

• Large body size (low surface:volume)• Bristly hair

• Many nest in rookeries• Males establish territories and harems

Marine MammalsB. Order Pinnipedia

1. Seals (19 Species)• Rear flippers can’t be rotated forward

• Swim with rear flippers Video Video

• Undulate body to move on land

• Include largest pinniped

• Elephant seals can reach 20 ft long and 3600 kg

• Threatened by hunting and coastal development

Weddell

Leopard Crabeater

Harbor

S. Elephant

Video

Marine MammalsB. Order Pinnipedia

2. Sea Lions (5 species)• Rear flippers can be rotated forward

• Swim with front flippers Video Video

• Rotate limbs and can walk on land

• External ears

3. Fur Seals (9 species)• Related to sea lions

• Formerly hunted for fur

Marine MammalsB. Order Pinnipedia

Marine MammalsB. Order Pinnipedia

4. Walrus (1 species)• Feeds on benthic invertebrates, mostly clams

• Tusks used for defense or as anchors in ice

Marine MammalsB. Order Carnivora

1. Sea otter (1 species)• Smallest marine mammal (average male 25-35 kg)

• No blubber layer

• Insulation from air trapped in dense fur

• Keystone predators in west coast kelp forests

• Voracious – Eat up to 25% of body weight daily

Marine MammalsB. Order Carnivora

1. Sea otter (1 species)

Marine MammalsB. Order Carnivora

2. Polar bear (1 species)• Semiaquatic

• Considerable time in water

• Feed primarily on seals

• Capture prey through breathing holes in ice

• Impacted by climate change

Marine MammalsC. Order Sirenia

• Manatees, Dugongs and Seacows

• Front flippers, no rear limbs• Swim mainly with tail Video

• Thick blubber layer

• Strictly vegetarian

• Manatees reach 4.5 m, 600 kg

• Major threats from coastal development and boat traffic

Marine MammalsC. Order Sirenia

Marine MammalsC. Order Cetacea

• Whales, dolphins, porpoises• 90 species – 85 marine, 5 freshwater (dolphins)

• Front flippers, tail, no rear limbs

• Streamlined for efficient swimming• Example of convergent evolution

Marine MammalsC. Order Cetacea

• Blubber

• Blowhole on dorsal surface