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Explore the fascinating world of marine birds and mammals, including penguins, pelicans, seals, and whales. Learn about their unique adaptations for life in the ocean and the impact of human activities on their populations.
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009b Marine Mammals & Birds
Phylum Chordata Subphylum Vertebrata • Class Reptilia • Class Aves (birds) • Class Mammalia
Birds Evolution http://www.zoology.ubc.ca/~bio336/Bio336/Lectures/Lecture5/dinobird.jpg http://www.phyletisches-museum.uni-jena.de/images/archaeopteryx_berlin_1864.jpg
Class 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
Penguins • Southern hemisphere only (Galapagos south to Antarctica)
Penguin Adaptations • 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 King penguin Adelie penguins 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 Prey • Larger penguins eat fish, squid • Smaller eat large plankton (krill) • Mostly feed near surface • Some dive to 1800+ ft, 22 mins Galapagos penguin
Penguin Nesting Gentoo penguin Magellanic penguins King penguin
Penguins Rockhopper penguin Macaroni penguins Yellow eyed penguins
Marine Birds Tubenoses • Albatrosses, shearwaters, and petrels Storm petrel Shearwater Albatross – longest wingspan
Marine Birds Pelicans and web-footed birds • Cormorants, frigates, gannets Brown pelican Cormorant NOAA Gannet Frigate NOAA
Marine Birds Gulls • Jaegers/skuas, terns, puffins, razorbills Herring gull Least tern Horned puffin
Marine Birds Feeding strategies
Marine Birds Beak shapes:
Marine Birds Shorebirds – beak length
Marine Birds Shorebirds • Sandpipers, plovers, coots Sandpiper Godwit Hawaiian coot
Marine Birds Shorebirds • Herons, egrets Great blue heron Black-crowned night heron Great egret
Marine Birds Shorebirds • Swans, geese, loons • Ducks, coots, grebes, mergansers Common merganser Wood duck Mute swans
Marine Birds Birds of prey • Eagles, ospreys
Human Impacts • Pollution – pesticides, PCBs, metals Bioaccumulation, biomagnification
Class Mammalia Whales & Dolphins Polar bear Sea otter Seals & sealions manatee Dugong
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 Streamlining Evolutionary 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 & 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
Dugong • 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
10,000 Dugong Range
Family Dugongidae Dugong dugong Steller's Sea CowtHydrodamalis gigas Discovered 1741, extinct 1768. 8.9 ft, 551-661lbs 30ft, 4.4 tons
Manatee • 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 9.8 ft, 800-1200lbs 3,000 in U.S.
Relationship between Sirenians and elephants (mtDNA) Asian elephant African elephant tmammoth tmastadon tStellar’s sea cow Dugong Ancestral mammals West Indian manatee Brazilian manatee West African manatee Other mammals 80 60 40 20 0 Million of years before present
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