Marine Birds

Physical Adaptations for the sea:

• Wing Shape– Long/slim = pelagic, months of

flying– Short wings = diving

• Feathers– Water-repellent feathers– More than land birds

• Webbed feet for swimming after prey• Thick skull bones and air sacs

around necks for head first dives• Salt glands

Behavioral Adaptations

• Breed later

• Fewer young – invest a lot of time into offspring

• Nest in colonies

• Long migrations

Most Common Marine Birds in Hawaii:

1. Albatrosses

2. Shearwaters and Petrels

3. Frigatebirds

4. Boobies

5. Terns and Noddies

Albatross

• See well at night, feed on squid

• Distinct courtship

• Once together, together for life …separate at sea, but return each year

• 2 main types: Layson and black-footed

• Largest seabirds in North Pacific

• Leave in June/July return in October

Shearwater and Petrels

• Long pointed wings

• Slender bodies

• See well at night

• Remain paired for life

• Dig burrows

• Awkward on land, legs so far back they cannot walk

• Migrate to C. America to feed

Frigatebirds

• Large, black, slim wings, with forked tail

• Males have red pouches for mating rituals

• Feed during the day

• “Great frigatebirds” most common in HI

• Efficient in the air, known to pursue other seabirds and rob their food

Boobies

• Designed for plunge diving (30 ft above)

• Well adapted for terrestrial and marine life

• Nest any month of the year

• Incubate by wrapping their feet around the egg (balls, fish floats)

• Common types: Brown, Red footed, Masked

Terns and Noddies

• Slender, graceful with long pointed wings and straight tapered bills

• Swim poorly, feet are too small

• Live aloft, sleeping during flight

• Ceremonial fish flights

Why are they important?

• IMPORTANT CONSUMER– over 400,000 tons of fish, squid,

crustaceans each year!

• Indicators for fish schools and land

• Bird feces (guano) = fertilizer

Threats to Marine Birds• Bycatch

– 100,000 albatross hooked on long-line fishing a year

• Overfishing• Hunting of birds and eggs• Introduced species

– Kill nesting birds, destroy habitat

• Biomagnification of toxins and pollutants

Hawaii Marine Bird Videos

• http://www.youtube.com/watch?v=C7cMihMeq3Y

• http://www.hawaiianatolls.org/video/nowramp020927.php