Hawai’i is one of the most
isolated lands in the world, sitting in the middle of the vast
Pacific Ocean, almost 2,500 miles distant from San Francisco, its
closest port-of-call. Up until the arrival of the first humans (some
1,700 to 1,200 years ago), the island chain was populated solely by
flora and fauna that arrived in one of three ways: via bird, winds,
or ocean currents. And many of those plants and animals that did
manage to make the long voyage evolved over millions of years into
completely new, distinct species.
downtown Hilo’s new
Palila mural,
painted by Kathleen Kam
(you can order a signed print of
the mural here)
It has been estimated that
there were some 8,500 native species on the Hawaiian Islands before
the arrival of the first Polynesian sailors, and that about 96% of
these were endemic—i.e., they evolved on the islands and were found
no where else in the world. Perhaps even more interesting is that
these endemic species are thought to have evolved from only about
1,000 original colonizing species. In other words, some eight new
species evolved from each one that made it to the islands. (Many of
these facts, as well as ones that follow, are taken from this document.)
A good example of many
differing species evolving from a single one is the honeycreeper.
Scientists believe that a single ancestral species arrived in Hawaii
about 20 million years ago, and that its descendants evolved into 47
new endemic species. The great diversity of the islands—from
parched deserts to tropical forests to alpine mountains—explains
the differences that evolved, with the new birds varying widely in
color, plumage, and bill shape.
It is not thought that the
arrival of the ancient Polynesians had a negative effect on these
endemic honeycreepers (or on other endemic species), for although
they would catch the birds on occasion for their feathers, the native
Hawaiians were conscientious about allowing their plants and animals
to flourish.
But with the arrival of
Captain Cook and the subsequent flood of non-Hawaiian visitors, the
endemic species—including the honeycreepers—began to suffer.
Several factors have caused this. With the introduction of the some
9,000 new plants and animals between 1778 and 1994 came many that were harmful to the birds: mosquitos (which carry diseases
that kill them); pigs, cows and sheep (which trample and eat the
plants they depend on); house cats (which prey on them); and
mongooses (which eat their eggs) are just a few of the introduced
species which are causing the die-off and extinction of Hawai’i’s
endemic birds.
In addition, the clearing of
forest land, cattle ranching, and real estate development have
resulted in the disappearance of virtually all the native vegetation
at the lower and middle elevations of the islands. As a result, most
of the honeycreepers’ habitat has been lost as well.
The Palila
is an endemic honeycreeper which currently lives only on the upper
slopes of Mauna Kea on the Big Island, and which is now listed as
“critically endangered.” (You can watch a PSA about it here.)
A few weeks ago Robin and I
volunteered for the day to plant seedlings for the Mauna Kea Forest
Restoration Project—an agency our neighbor Jackson Bauer works
for—which is restoring the Palila bird’s dwindling native
habitat. An overview of what the MKFRP does (with some cool photos of
snow on the mountain) can be found in this blog post by the American Bird Conservancy. As explained in
the post just cited,
This project is working to
restore high-elevation dry forest for the Palila, a Hawaiian
honeycreeper listed as endangered in 1973. This Critically Endangered
bird now occurs only on the southwestern slope of Mauna Kea, which is
less than five percent of its historical distribution on Hawai’i
Island.
Palila are dependent upon māmane
trees, a legume (pea family), that provides these birds with about 90
percent of their diet in the form of seeds that are toxic to most
other animals, yellow flowers, young leaves, and moth larvae found in
the seed pods.
a healthy māmane tree
Unfortunately, even on the
five percent of the Palila’s historical distribution that still
exists, the māmane is suffering, largely as a result of sheep and
cattle grazing. Although most of these animals have now been removed
from the area, the damage has been done and there are far fewer trees
than necessary for the Palila to survive. Our neighbor Jackson tells
us that as of the last count, the estimate is that there are now less
than 2,000 of the birds in existence.
Palila habitat, with lone
dead māmane tree
After a walk through one of
the more pristine areas of Palila habitat (during which we were lucky
enough to sight two of the rare birds!), Jackson gave our volunteer
group a demo on planting techniques. Here he is, a keiki (seedling)
in one hand and digging tool in the other:
We split up into groups of
diggers and planters. Here you can see the diggers:
Robin is nearest the
camera
And here are more keiki
being brought in for us to plant:
By the end of the day we had
planted some 800 new seedings.
The MKFRP is doing a good
job of getting the word out locally about the danger of extinction
for the Palila. Here’s a photo of Robin and me at the recent Palila
Parade, to celebrate the unveiling of the Palila mural downtown (see
photo above).
Robin is a māmane branch
and I’m a little rain cloud
(photo: Anya Tagawa)
But they could use more
help! If you’d like to learn more about the Palila and their plight
and efforts to save the species, and/or volunteer for the project or
donate money, click here. They have a Facebook page
you can like, too!
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