Page 68 - Environment: The Science Behind the Stories

The newly introduced organisms wreaked havoc because of the few remaining patches of malaria-free native forest on
native Hawaiian organisms were unprepared to resist them. the island.
Hawai‘i is so isolated that only one mammal—a bat—had ever Conservation biologists and managers have worked hard
arrived naturally. As a result, plants had faced no pressure to to keep the Hakalau Forest protected. Jack Jeffrey was the ref-
invest in defenses (such as thick bark, spines, or chemical tox- uge biologist here for 20 years, and led a number of innovative
ins) against plant-eating livestock. Likewise, nothing had led projects to save native plants and birds from extinction. Man-
birds to evolve defenses against voracious nest predators such agers at Hakalau have fenced out pigs to safeguard forested
as rats and mongooses. The vulnerable native species were areas, and refuge staff and volunteers have planted thousands
easy pickings, and many were soon wiped off the face of the of native plants in areas deforested by cattle grazing. Young
planet. restored native forest is now regrowing on thousands of acres.
With the arrival of people, domestic animals, and invasive More birds are using this restored forest year by year.
plants also came diseases. The native fauna were not adapted to Today global climate change is throwing up a new chal-
resist diseases they had never encountered. Avian pox and avian lenge. As temperatures warm, mosquitoes move upslope,
malaria spread through Hawaii’s birds. Malaria and the mos- and malaria and pox spread deeper into the remaining for-
quitoes that carry the disease killed off the natives everywhere ests, so that even protected areas such as Hakalau are not
except on the high slopes of the mountains, where it becomes immune. The next generation of managers will need to inno-
too cold for the malaria parasite to survive. Today few native for- vate novel strategies to fend off extinction for the island’s
est birds exist anywhere on the Hawaiian Islands below 1500 m native species.
(4500 ft) in elevation. Plenty of challenges remain, but the restoration successes
The aki being watched by Jack Jeffrey’s group inhabits at Hakalau Forest so far provide hope that through responsible
the Hakalau Forest National Wildlife Refuge, which sits high on management we can save Hawaii’s native flora and fauna and
the slopes of Mauna Kea, a volcano on the island of Hawai‘i, preserve the priceless bounty of millions of years of evolution
the largest island in the chain. At Hakalau, native birds find one on this extraordinary chain of islands.

Evolution: The Source of inhabited solely by microbes to a lush cornucopia of millions
of species (Figure 3.1).
Earth’s Biodiversity A species is a particular type of organism or, more pre-
cisely, a population or group of populations whose members
The honeycreepers and the other native animals and plants of share characteristics and can freely breed with one another
Hawai‘i help reveal how our world became populated with and produce fertile offspring. A population is a group of indi-
the remarkable diversity of life we see today. Scientific study viduals of a particular species that live in a particular area.
shows us that our planet has progressed from a stark world Over vast spans of time, the process of biological evolution

(a) `I`iwi (Vestiaria coccinea) CHAPTER 3 • Ev ol u T i on, Bi odiv ER si T y, A nd Po P ul AT i on E C ology
(d) Happyface spider (Theridion
grallator)

Figure 3.1 Hawai‘i hosts a treas-
ure trove of biological diversity.
(b) Nēnē (Branta sandvicensis) (c) Haleakala silversword (Argyroxiphium
sandwichense) 67

M03_WITH7428_05_SE_C03.indd 67 12/12/14 2:54 PM