Aerodynamics & Flight Anseriformes 3 families, 162 species Male Wood duck. All of the photos of ducks that follow are males. Wood Ducks nest in holes in trees, or in artificial nest boxes. Anseriformes 3 families, 162 species

Anhimidae -- Screamers Slender toes with rudimentary web at the toes’ base. Stout spurs at the bend of the wings. Their skin is filled with small air bubbles like bubble rap and produces a crackling sound when pressed. 3 S American species

Anseranatidae – Magpie Goose The odd Magpie Goose of Australia has a long hind toe and partially webbed feet. It breeds in large colonies and presents food to its young, a unique behavior among waterfowl. Anseranatidae – Magpie Goose

Anatidae Mute Swans

Canada Geese

Bufflehead

Common Goldeneye

American Widgeon

Surf Scoters. San Francisco bay supports 40% of the Pacific flyway’s winter scoter population. Sea and Bay duck populations have declined precipitously in the past 20 years. Perhaps related to introduction of the Asian Clam in 1986. In early 1990s , this clam reached peak densities of 10,000 per square meter in SFB. This clam accumulates higher concentrations of heavy metals in its tissues than native clams.

Hooded Merganser

Common Eider

Mallard

Canvasback

Conservation Ducks Unlimited National Audubon Society 700,000-member wetland conservation organization National Audubon Society 500,000 members

Aerodynamics & Flight Aerodynamics of soaring flight Flapping flight Wing types Types of flight

THRUST = DRAG LIFT = WEIGHT

Primaries mainly thrust Secondaries mainly lift Black-bellied plover wing www.ups.edu/biology/ museum/SEPLwing3.jpg Primaries mainly thrust Secondaries mainly lift

Airfoil

Bernoulli’s Principle

Lift increases with Angle of attack Surface area Air speed squared

Lift increases with angle of attack

Video clip from Life of Birds detailing aerodynamics of flight.

Larger birds have proportionately smaller wings and must fly faster Speed = k M1/6 10 kg bird flies 2.2 faster than 0.1 kg bird

Drag Viscous resistance encountered as bird moves through the air Two types of drag: profile and induced Profile drag results from air flow over the body, reduced by streamlining Induced drag more complex

Induced drag Wingtip vortex

C-130

Magnitude of induced drag depends upon wing loading and aspect ratio

Wing loading = weight/wing area Induced drag is directly proportional to wing loading

Aspect ratio Induced drag is inversely related to aspect ratio The higher the aspect ratio the lower the flight costs

Aspect ratio = wing span/mean chord

Deflection currents

Dynamic soaring

Flapping flight

Video clip from Life of Birds showing pigeon launching into the air Video clip from Life of Birds showing pigeon launching into the air. Vertical take-off demands so much energy that birds a little bigger than a pigeon cannot do this twice in succession.