Post on 25-Dec-2015
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
• 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