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Advantages to size and mobility
- access to higer volume for foraging
- specialized niches
- ability to utilize patchy prey
- ability to select different habitats for different stages of life history
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New Technology to study animals...
- Time-Depth Recorders
- Acoustical tags
- Satelitte tags and GPS
- Attached cameras
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Osteichthyes
- -bony fish
- -skeleton made of bone
- -Swim bladder to regulate boyancy
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Types of fish body shapes
flattened, elongated, laterally compressed, irregular (seahorse)
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Warning Coloration
dangerous, bad tasting, poisonous
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Cryptic Coloration
blend with the environment, hide from predators, stalk prey
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Disruptive Coloration
break up outline of individual fish to confuse predators
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Dark Top, light bottom, camoflauge in open water
Countershading
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Sharks that bite pieces from large prey
•Tiger shark – Diverse stomach contents
•Great white shark – Wound and wait
•Cookie cutter shark – Cut out chunks
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ingest smaller prey whole
Nurse shark (benthic vertebrates)
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Filter Plankton (gill rakers)
•Whale shark – Warm
•Basking shark – Cold
•Manta ray
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bony fish feeding
a.Capture large prey whole
•Barracuda
•Frogfishes
- b.Pickers - Ingest smaller prey
- whole
•Butterflyfish, Slipmouth
- c.Grazers
- •Parrotfish
- •Filefish
- d.Filter plankton – Gill rakers
- •Anchovies
- •Sardines
- •Herrings
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Anadromous
- spawn in fresh water, spend most of life in ocean
- Ex. Salmon
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Semelparous
Die after giving birth, Advantages are the eggs have a higher chance of survival
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Homing facto
enabled by olfactory imprinting
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Catadromous
- Spawn in oceans, spend most of life in freshwater
- Ex. eels
•Spawn in Sargasso Sea (400-700 m or deeper)
•Semelparous
•Eggs hatch into leptocephalus larvae
•Larvae spend a year or more as plankton then undergo metamorphosis into juveniles
- •Adults spend 10-15 years in fresh water before migrating to
- Sargasso Sea to spawn
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A. Pinnipeds
Marine Mammals
- •apparently entering the ocean to take
- advantage of the new and abundant food resources created by an upwelling of
- colder, nutrient-rich waters along the coasts of Europe and North America.
•
- • phocid seals (earless, or true, seals) and the otarioid
- seals (eared seals and walruses) diverged from a bearlike or doglike common
- ancestor about twenty-five million years ago. (interestingly, the skulls of sea
- lions, bears, and such canids as large dogs and wolves are nearly
- indistinguishable at first glance.)
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Pinnipeds (seals etc)
- eat squid and fish
- predators are sharks, killer whales and polar bears
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Grey Seals
damage fishing nets im attempt to eat caught fish
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Threats to sea lions and seals
oil spills, algae blooms, habitat loss, competition, removal of seals
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Carnivora
Sea otters-smallest marine mammal, no blubber layer, keystone predators in kelp, voracious
Polar Bears- semi aquatic, feed primarily on seals through air holes in ice, affected by climate change
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Sirenia
- Manatees, Seacows, dugongs
- strictly vegetarian, front flippers, swim mostly with tail, threatned by coastal development and boats
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Cetacia
whales, dolphins, porpoises
- •Streamlined for efficient swimming
- •Example of convergent
- evolution
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Mysticeti (baleen whales)
- includes largest animal on earth, blue whale
- baleen made of kariten
- squeeze water through baleen and lick of remaining food
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Odontoceti (Toothed Whales)
a.Sperm whales – 3 species
•Sperm, Dwarf Sperm, Pygmy Sperm
- •Bulbous head contains spermaceti (waxy substance) that may
- function in buoyancy and sound generation
- •Sperm can dive to 3000 m and stay
- under water for up to two hours!
- •Feed on fishes and squids, esp.
- giant squids
•Produce ambergris, undigested material in stomach
b.Toothed whales – 30 species
- •Beaked, Beluga, False Killer,
- Narwhal, Orca, Pilot
•Most common in cold water
- c.Dolphins & Porpoises – 33
- species
•Distinctive beak
•Travel in pods
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