Tip:
Highlight text to annotate it
X
Bridging the gap between land and ocean,
seabirds are key players in island ecosystems.
They play an important role in cycling nutrients
as a large number of seabirds commute from sea
to land,
depositing guano, the natural fertilizer which helps plants grow.
Because seabirds forage over a wide range of marine habitats and are
a top ocean carnivore,
they are good indicators of the health of marine food sources and ecosystems.
Seabirds may nest on the ground,
on cliffs,
in trees,
or in burrows from coastal to mountainous areas.
This brown *** has built her nest on a cliff ledge.
Brown *** typically lay two eggs,
but often only one chick survives.
Many seabirds only come ashore during the breeding season
where they nest in colonies that number into the thousands.
During the breeding season, many seabirds leave their nests in the early morning to forage for fish,
squid, and crustaceans to share with hungry nestlings.
Some species travel many miles from shore to find food.
Throughout the Pacific Island Network
seabird numbers have dropped significantly,
and nesting and roosting sites have vanished from many islands.
Prior to human contact
seabirds were abundant,
but shortly thereafter
began a dramatic decline.
Predation by humans and introduced predators such as rats,
pigs,
mongooses, and cats
account for much of the loss.
Coastal habitats, where many seabird species live,
have been extensively altered by agriculture and development.
Because seabirds are a vital natural resource,
the National Park Service Inventory & Monitoring Program is supporting
seabird monitoring in Hawaii and American Samoa.
Haleakala
and Hawaii Volcanoes National Parks
are home to one of the most endangered seabirds in Hawaii,
the Hawaiian petrel,
or uau.
This burrow nesting species makes its home within lava and cinder fields
at high elevations.
When monitoring, biologists look for visual clues to indicate whether a
petrel is using a burrow.
(Biologist) This is a feather.
It doesn't like that fresh.
It could be from last year.
Fresh feathers,
footprints,
droppings, and eggshell fragments in and around the burrow are good indicators of
recent activity.
Toothpicks are often placed across the entrances to help biologists determine
if petrels or other animals are using the burrow.
When a petrol leaves or enters a burrow, several toothpicks are displaced, whereas
a rat may displace only one.
The highest seabird diversity of any
national park in the Pacific islands
occurs at the National Park of American Samoa.
Observations of
four common species of seabirds will be made by boat along the park shoreline.
Using this observation data,
biologists will monitor and detect changes in these important seabirds.
Through long-term monitoring,
park managers can develop and refine conservation and management programs to
protect seabirds and their habitats.
This will ensure that these magnificent birds will continue to have
a place of refuge in America's national parks.