Marine Mammals & Birds 009b. Phylum Chordata Subphylum Vertebrata Class Reptilia Class Aves (birds)...
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Transcript of Marine Mammals & Birds 009b. Phylum Chordata Subphylum Vertebrata Class Reptilia Class Aves (birds)...
Marine Mammals & Birds
009b
Phylum ChordataSubphylum Vertebrata
• Class Reptilia• Class Aves (birds)• Class Mammalia
Class Aves
Birds
http://www.phyletisches-museum.uni-jena.de/images/archaeopteryx_berlin_1864.jpg
Evolution
http://www.zoology.ubc.ca/~bio336/Bio336/Lectures/Lecture5/dinobird.jpg
Class AvesClass Aves
Characteristics
• Warm blooded• Feathers and wings• Hollow bones• Horny bill• Lungs have air sacks• Hard egg shell
Marine Birds
• Only 3% of all bird species• Evolved from different
groups of land birds• Spend significant part of
life at sea• Feed on marine organisms
Marine Birds
• Must nest on land
Marine Birds
• Salt secreting glands
• Webbed feet for swimming (not all)
Marine Birds
• Dense waterproof plumage (except commorants and some terns)
Marine Birds
• Migrations (not all)• Arctic tern -
24,000 mi roundtrip between Arctic and Antarctica
• Sooty shearwaters - 40,000 mi/yr
Penguins:
• 17 species found in southern hemisphere• Spends 75% of lifetime in water
Fairy (aka Little blue) penguins – up to 16 in
(recovering from oil spill)Emperor penguins - up to 45 in
• Southern hemisphere only (Galapagos south to Antarctica)
Penguins
• Heavy, solid bones for diving• Watertight feathers (up to 70 per sq. in.) • Blubber for insulation• Oil gland for coating feathers• Black & white counter shading• Deep divers
- 500 m, 15 min.• Paddle-like feet• Streamline, fusiform body
- 15 mph• Social
Penguin Adaptations
• Don’t fly in air, but swim very well (fly through the water)
• Wings act as flippers
Adelie penguins
King penguin
Emperor penguins
Penguin Adaptations
• Eyes better adapted for underwater vision than air
• Adapted for colder waters and air temps
Black-footed penguin (aka African, Jackass)Gentoo penguin
Penguin Adaptations
• Larger penguins eat fish, squid
• Smaller eat large plankton (krill)
• Mostly feed near surface
• Some dive to 1800+ ft, 22 minsGalapagos penguin
Penguin Prey
Magellanic penguins
King penguin
Gentoo penguin
Penguin Nesting
Penguins
Rockhopper penguin
Macaroni penguins
Yellow eyed penguins
Altruism
Nests on pack ice
Rookery
Marine Birds Tubenoses
• Albatrosses, shearwaters, and petrels
Albatross – longest wingspan
ShearwaterStorm petrel
Marine Birds
Pelicans and web-footed birds Cormorants, frigates, gannets
Brown pelican
Cormorant
NOAA
NOAA
GannetFrigate
Marine Birds
Gulls• Jaegers/skuas, terns, puffins,
razorbills
Herring gull
Horned puffinLeast tern
Marine Birds
Feeding strategies
Marine Birds
Beak shapes:
Marine Birds
Shorebirds – beak length
Marine BirdsShorebirds•Sandpipers, plovers, coots
Sandpiper
Hawaiian coot
Godwit
Pacific Golden Plovers
Marine Birds Shorebirds
• Herons, egrets
Great blue heron Black-crowned night heron Great egret
Marine BirdsShorebirds
• Swans, geese, loons • Ducks, coots, grebes, mergansers
Mute swans
Common merganser
Wood duck
Marine Birds
Birds of prey• Eagles, ospreys
Human Impacts
• Pollution – pesticides, PCBs, metals
Bioaccumulation,biomagnification
Class MammaliaClass Mammalia
Dugong
manatee
Sea otter
Whales & Dolphins
Polar bear
Seals & sealions
Return to the Oceans Mammals have returned to the oceans
multiple times
Adaptations• vivipary• suckling young• thermoregulation • feeding• diving• osmoregulation
We’ll look at adaptation in marine mammals from the least to the most
Adaptations for diving • Exchange a large amount of air on each breath • Up to 90% in each breath (humans exchange
about 20%)• Blood with more oxygen carrying capacity • Heart rate slows • Blood flow shunted • Higher concentration of myoglobin in the
muscles• Collapsing lungs • Dive with no air in contact with blood vessels
to avoid problems of nitrogen being forced in
Fusiform Shape and StreamliningEvolutionary Convergence
Two basic bioenergetic strategies used by animals :
• Endothermy “warm blooded”
• Ectothermy “cold blooded”
Thermoregulation
Concurrent exchange
Countercurrent exchange
Marine mammals
Characteristics of marine mammals:• Warm-blooded• Breathe air• Have hair (or fur)• Bear live young• Females have mammary glands that
produce milk for their young
Marine mammals: Order Sirenia
• Sirenian characteristics:– Large body size– Sparse hair all over body– Vegetarians– Toenails (on manatees only)
• Includes:– Manatees– Dugongs
Manatee & DugongManatee & Dugong• Most complete transition to marine life
along with whales and dolphins • Related to the elephant, but common
ancestor didn’t look like either of them • Once many more species around • Large layer of blubber • Origin of the mermaid myth • Herbivores• Nostrils on top of snout have valves to
keep water out • Both species have one calf at a time • Tend to have a single calf every 3 years
Location: coastal and inland waters of the western Indo-Pacific region
• Dugongs are exclusively marine and have a dolphin-like tail
• Dugongs tend to dig seagrass rhizomes
• Predator includes tiger sharks
Dugong
Dugong Range
10,000
Family Dugongidae
Dugong dugong Steller's Sea CowtHydrodamalis gigasDiscovered 1741, extinct 1768.
8.9 ft, 551-661lbs
30ft, 4.4 tons
Location: Florida, Central and South America
• Manatees have paddle-like tails and frequent freshwater
• Manatees tend to crop and grab with prehensile lips
• Manatees are larger than dugongs • Few predators
Threats:• Careless boaters • Habitat loss
Manatee
Manatee
9.8 ft, 800-1200lbs3,000 in U.S.
Million of years before present
80 60 40 20 0
Ancestral mammals
Asian elephant
African elephant
tmammoth
tmastadon
Dugong
tStellar’s sea cow
West Indian manatee
Brazilian manateeWest African manatee
Other mammals
Relationship between Sirenians and elephants (mtDNA)
Marine mammals: Order Carnivora
• All members of order Carnivora have prominent canine teeth
• Includes:– Sea otters– Polar bears– Pinnipeds (flipper-footed)
• Walrus• Seals• Sea lions/fur seals
Hawaiian Monk Seal
Sea OtterSea Otter
Sea Otter• Enhydra lutris
– Native to north Pacific– 394,000 hairs/cm2
– No blubber– Female 45 lbs; Male 65lbs – Diet: Sea urchins,
abalone, mussels, clams, crabs, snails and about 40 other marine species.
– Uses tools
– Dives to 330 ft
– Rests in coastal kelp forests
Pop size: 22,000 to 27,000Weight: 550 to 1,700 pounds
Polar BearPolar Bear
Polar Bear• Ursa maritimus
– United States, Canada, Russia, Greenland and on the Arctic islands of Norway
– Male: 10 feet tall and weigh over 1400 lbs
– Female: seven feet and weigh 650 lbs
– wild polar bears live up to age 25.
– Good swimmers
– Thick blubber
– Thick fur
Polar bears
• Polar bears are the least adapted to the marine lifestyle
• Land animals that are adapted to the cold
• Considered marine mammals because they feed almost exclusively on marine organisms
• Very good swimmers, but can’t dive below surface well
• Hunt seals and walruses, occasionally cetaceans
Range: • Circumpolar in Arctic• Range depends on sea ice
• normal range occasional range over pack
occasional range over permanent ice
PinnipedsPinnipeds
Sea LionWalrus
Family Phocidae
Family OtariidaeFamily Odobenidae
Hawaiian Monk Seal
Pinnipeds
Order Pinniped (seals, sea lions, & walruses)Family Phocidae- true, earless sealsFamily Otariidae- eared seals and sea lionsFamily Odobenidae- walruses
• 34 known species• Evolved 20 mya from Order Carnivora (ancestors of dogs
and bears)• Differ in possession of external ears and mode of
locomotion
Biology and Natural History
Differences between seals and sea lions/fur seals
Family Phocidae
Hawaiian Monk Seal
• Lack external ears• Hind flippers propel them while swimming• Front flippers act as rudders• Travel on land is difficult (wiggle)
Sea LionFamily Otariidae
• Eared seals• Front flippers propel animal when swimming• Rear flippers act as rudders• Fairly mobile on land
Walrus
Family Odobenidae
• Found in Arctic region• Lack external ears• Paddle with front flippers• Rear flippers act as a rudder• Fairly mobile on land
Pacific walrus is in lavender, Atlantic walrus is in rose.
Walrus Range Map
Walrus FactsLocation: • Bering sea, Pacific Ocean, Atlantic Ocean, Arctic Ocean
Pop Size:• 250,000
Size: • Weight: 2,000-3,500 lb.
Breeding: • Sexually mature late
- females, usually 6-7 years- males, 15 years.
• Produce few offspring
Walrus FactsLifestyle
• Habit: Gregarious, living mainly
in herds.
• Diet: Benthic suction feeders.
Feed mainly on bivalve
mollusks, but also other
invertebrate marine animals,
fish, sometimes seals and
whales.
• Predators: polar bears, killer
whales, and humans
• Lifespan: Up to 40 years.
Walrus Facts• Swim speed: 7-35 kph• Tusks:
- Both male & female- Used for dragging body across land or ice- Symbolize age, sex, and social status
• Pharyngeal pockets:- 2 found on either side of the esophagus that hold up
to 50 liters of air ). - For buoyancy; these pockets facilitate sleep in the
water in an upright position- May be used to amplify mating calls
Whales, Dolphins, Whales, Dolphins, & Porpoise& Porpoise
Age: Early Eocene, 50 million years oldLocation: Pakistan
Pakicetus attocki
Whale Evolution
Ambulocetus natans in action. A reconstruction of an early close cousin of whales.
Marine mammals: Order Cetacea
Marine mammals: Order Cetacea
• Cetacean characteristics:– Blowholes on top of skull– Skull telescoped (streamlined shape)– Very few hairs
• Includes:– Whales, dolphins, and porpoises
Two suborders of order Cetacea
• Suborder Odontoceti (toothed whales)– Echolocate (send sound through water)– Includes killer whale, sperm whale,
dolphins, porpoises, and many others
• Suborder Mysticeti (baleen whales)– Have rows of baleen plates instead of teeth– Includes blue whale, finback whale,
humpback whale, gray whale, and many others
(55 mya- entered sea)
Differences between dolphins and porpoises
• Dolphins have:– An elongated snout
(rostrum)– A sickle-shaped
(falcate) dorsal fin– Conical-shaped
teeth Killer whale jawbone
Differences between dolphins and porpoises
• Porpoises have:– A blunt snout
(rostrum)– A triangle-shaped
dorsal fin– Spade-shaped teeth
Echolocation • Sensing environment • Produce clicks that travel out, hit
objects and reflect back • Produced by a structure in the airway
called the “monkey lips” • Sound received through the lower jaw • Low frequency clicks travel further but
can only be used for big objects • High frequency clicks can discriminate
small objects but don’t travel as far
Deepest Diver
(3km~1.5 miles)
Mysticeti: The baleen whales
• Mysticeti whales have baleen instead of teeth
• Baleen plates:– Hang as parallel rows from the upper jaw– Are made of keratin– Are used as a strainer to capture zooplankton– Allows baleen whales to eat krill and small
fish by the ton
Baleen
Types of baleen whales
• Baleen whales include three families:– Gray whale (a bottom-feeder with short
baleen)– Rorqual whales (medium-sized baleen)
• Balaenopterids (blue whales, finback whales, and other large whales )
• Megapterids (humpback whales)
– Right whales (surface skimmers with long baleen)
Whale Migration
Whale Carcass Removal
http://perp.com/whale/video.nc.html
1. What characteristics distinguishes the three groups of pinnipeds?
2. Why do whales migrate to Hawaii?3. What is echolocation?4. Which marine mammals lack blubber?5. Why are penguins black and white?6. What is the difference between an
odontocete and mysticete? 7. Why don’t whales get the bends?8. Why shouldn’t you load a dead whale
with dynamite?
Inquiry