David J. Flaspohler, an avian ecologist and conservation biologist at Michigan Technological University, writes from Hawaii, where he is studying the influence of human activities on birds and the natural ecosystems that support them.
Tuesday, May 22
One of the great pleasures of learning bird songs comes in the drowsy predawn twilight. Through the window comes the voice of the first bold male offering up his species? diagnostic song. From my bed in a friend?s cabin 30 miles north of Hilo this morning, the first sound to break the silence is the emphatic, repeated ?whit-cheer!? of the northern cardinal, a bird I grew up hearing in southern Michigan. Next comes the soft cooing of Asian spotted and zebra doves, followed by the occasional harsh notes of the common myna, an import from India. Finally, I hear the slurred warbles of the Japanese white-eye. Later, with a cup of coffee, looking out over the pasture and woodlots spreading down to the sea, I hear and see a rich and complex ecosystem, almost none of which belongs here.
It is quite conceivable that a casual visitor to Hawaii could spend a pleasant holiday of a week or two and not see a single native Hawaiian species. Nearly all native lowland ecosystems in Hawaii have been replaced by nonnative species, including nearly all plants, birds, reptiles, amphibians and insects. Human residents and tourists concentrate themselves in these areas near the ocean, so it is even possible to grow up in many parts of Hawaii thinking that mynas, doves, papaya, eucalyptus, geckos and even mosquitoes have always been here.
To see, hear and smell native Hawaiian forests, you need to get away from the beaches and go up in elevation where most of the exotic birds disappear. Our research in these kipuka forests is aimed at understanding how kipuka size and introduced rats influence kipuka food webs and the native birds. But if the birds in these kipuka are imperiled, some listed and others being considered for listing under the Endangered Species Act, Hawaii is also home to a few bird species even worse off.
To see what intensive care looks like for the most critically endangered birds, I spend a morning at the Keauhou Bird Conservation Center in Volcano, Hawaii. Rich Switzer, manager for the Hawaii Endangered Bird Conservation Program at the San Diego Zoo, meets me at the gate, and we drive up to a compound of one-story buildings scattered within a sparse ohia forest. The mission of Keauhou is to conserve the most critically endangered Hawaiian birds through captive breeding and, with careful planning, reintroduce them back into the wild.
We remove our shoes, a common practice in Hawaii, but here a precaution against spreading disease. We first tour a darkened hallway with rooms on both sides and small vertical windows along the walls, looking into aviaries housing palila, Maui parrotbill, puaiohi and apapane. It is the breeding season, so we speak in whispers. There are only about 500 parrotbills left, and they are found only on a small part of Maui. The puaiohi is even rarer. It is one of only two endemic thrushes left in Hawaii and is found only at the highest elevations on Kaua?i.
Next, we visit the extensive aviaries dedicated to saving one of the rarest birds in the world ? the Hawaiian crow, called an ?alala, which no one has seen in the wild since 2002. Prior to the disappearance of the wild birds, a small population was established in captivity with the hope of preventing their extinction. We enter a control room with a dozen black-and-white screens streaming live video from each aviary. Lisa Komarczyk, a senior research associate at Keauhou, closely monitors a mated pair of ?alala and a nest platform covered with sticks assembled by the female. Lisa records how frequently the female nestles in the nest cup, a precursor to egg laying, and as we watch, a female named Moa Nui sits quietly as her mate perches in the background.
The ?alala is a relative of the crows, ravens and jays found across much of the globe. This family is among the smartest birds, with some species using tools and in other ways showing the capacity for complex thought and for cultural transmission of learned information. Today, with the ?alala facing extinction, such traits cut both ways. A greater capacity for learning might be advantageous as this bird struggles to survive in a changing world. Yet cultural information like where and when to find food and how best to react to predators is at least somewhat learned from experienced older birds. It does not take long in captivity for such abilities to disappear. An earlier effort to reintroduce ?alala into the wild failed in part because the native hawk, the ?io, was able to capture birds that may have been weakened by introduced disease or lost adaptive responses to the predator, or both.
As we watch the monitor, Rich points to a video screen showing a female sitting quietly on her nest. He and Lisa note some rhythmic head movements and contractions of the bird?s body. We note that the fine black feathers on the bird?s head have become erect, and the bird gives a subtle but distinct shudder. They?ve seen egg laying many times before, but for me, this is thrilling. I ask if they think she just laid, but they are noncommittal. The female shuffles a bit and rises to reveal a shiny spotted egg. Bending her head down, she uses her bill to delicately arrange the egg beneath her. She then settles her warm belly down over the egg and waits to see what the future will bring.
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