Amazing Facts

Deep Sea Birds








A seabird is a bird that spends most of its time at sea. Seabirds' is a
general term used to collectively describe any species of bird which
spends a substantial part of its life foraging and breeding in the
marine environment. Birds considered to be seabirds include gulls,
terns, albatrosses, petrels, shearwaters (muttonbirds), cormorants,
gannets and boobies.





Seabirds spend much of their lives roaming the
oceans in search of prey. Most species tend to forage on their own,
though large feeding flocks will gather at rich or passing food
sources. Squid, fish and krill are common sources of food. Birds are
known to follow fishing vessels, aggressively competing for discarded
fish and baits.





Many seabirds, such as albatrosses and petrels have long life spans
with some individuals known to live for more than 60 years. They have
low rates of natural mortality and low rates of mortality among their
offspring. Most species achieve sexual maturity at 5-12 years of age
and breed in colonies on remote islands, with the pair-bond being
reinforced by elaborate courtship displays. While some species breed
annually, others breed only every second or third year.



Parental duties are shared by both sexes. Petrels and shearwaters nest
in simple scrapes or in a burrow or natural hole. Albatrosses nest in
the open and, where nest material is available, build large bowl-shaped
nests. Each pair lay a single, large (relative to body size), white egg
which both parents incubate for 35-85 days in alternating shifts. After
hatching, chicks are brooded for a short period until they are able to
regulate their own temperature. After this period the chick is
generally left alone, with parents returning only to provide food. Both
parents feed the chick until it fledges at 110-304 days (depending on
the species).





Seabirds occur widely across the world's oceans.
Twenty-two of the world's 24 albatross species occur in the Southern
Hemisphere. Nineteen of these species occur in Australian waters, and
five of these also breed in Australia. Many species, such as
Grey-headed Albatrosses, are extremely dispersive, spending most of
their time over the surface waters of the High Seas. In contrast,
others, like adult Shy Albatrosses, tend to be sedentary, regularly
foraging over the coastal waters of southern Australia throughout their
adult lives.






   
Related Tags: Sea  Birds  Water  
 
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