The Hunt for the Ivory-billed Woodpecker
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The elementary school student questioning if El Niño occurs anywhere besides the Pacific Ocean. The researcher investigating connections between Arctic ozone depletion and global climate change. The citizen scientist interested in how changing land cover and use affects animal migration patterns. And the businessperson projecting future needs for harvest, delivery and storage of crops. All of these people are Earth Explorers -- they are all connected by their curiosity about Earth system processes. This series will introduce you to NASA Earth Explorers, young and old, with a variety of backgrounds and interests.
When Gene Sparling saw a striking black-and-white bird while kayaking along the Cache River in Arkansas in February 2004, it was not just any other sighting. Sparling is not a bird expert, but the naturalist in him knew that the bird’s markings were not those of the common pileated woodpecker that lives in those old forests.
Image to right: An artist's image of what an ivory-billed woodpecker looks like. Credit: George M. Sutton/Cornell Lab of Ornithology
The only explanation was an ivory-billed woodpecker. The ivory-billed -- slightly larger than, but aesthetically similar to, its pileated counterpart -- is a majestic bird that many scientists had thought was extinct. It had last been seen about 60 years ago.
Realizing the importance of his finding, Sparling went home to write about it in an online bird chat. Ornithologists have since confirmed that at least one ivory-billed woodpecker still lives in Arkansas.
Now, scientists at NASA are using laser technology to help find the bird and determine whether it has lived reclusively in southeastern U.S. forests all this time. Finding the woodpecker would be a biological triumph and would have important consequences for ecological conservation, says Woody Turner, a scientist at NASA's headquarters in Washington, D.C.
Turner, like Sparling, is something of a naturalist. He grew up a bird-watcher in Tennessee, calls himself a "wildlife nut" and says he cannot remember a time when he was not fascinated by animals. Yet, he did not initially plan a career in conservation or other Earth sciences. He first joined NASA's International Relations Division after earning a master's degree in international relations.
Image to left: Woody Turner is lending his expertise to the search for the ivory-billed woodpecker. Credit: NASA
Later, Turner moved to NASA's Earth science program because of his interest in wildlife and nature. Soon after, he went back to school to pursue a master's degree in conservation biology from the University of Maryland. Now, he leads NASA's effort in the search for the ivory-billed woodpecker by providing support to researchers at the U.S. Fish and Wildlife Services, the U.S. Geological Survey and the University of Maryland.
The researchers are using an instrument called the Laser Vegetation Imaging Sensor, or LVIS (pronounced "Elvis"), developed by scientists at NASA's Goddard Space Flight Center. The instrument emits laser light pulses straight down into the forest canopy. The light bounces off tree branches, leaves and the ground, and reflects back to the instrument, which reads the return signal. Scientists can convert this data into three-dimensional images.
In June and July 2006, the research team flew an aircraft carrying LVIS over 1.2 million acres of land in Arkansas, including the area where the kayaker had spotted the bird in 2004. Scientists at the University of Maryland are now analyzing the laser data and creating 3-D maps showing the structure of the forest between the ground and the treetops.
The scientists will compare this information with what they already know about the woodpecker's habitat from a well-known study published in 1942 and other scientific works. The references give the researchers a rough understanding of the kind of forests the bird likes. They will look for matching environments on the 3-D Arkansas forest map obtained from LVIS to narrow down where the bird could still live.
"We have a historical understanding of its habitat," Turner said. "We're trying to use that historical data to guide where one might want to look today."
If the ivory-billed woodpecker does exist, LVIS data could help find it, Turner says. Larry Handley agrees. Handley is a researcher at the USGS National Wetlands Research Center who supervised the LVIS data gathering. He says that without the instrument, people would have to walk all over the forest to search for the woodpecker's habitat. Using the laser sensor makes the task much easier.
Image to left: An image produced from the airborne LVIS instrument shows a three-dimensional view of treetops and vegetation in the tropical forest of La Selva, Costa Rica. The color indicates the amount of laser energy reflected from trees and leaves back to a sensor on board the aircraft. Credit: John Weishampel, University of Central Florida. Credit: NASA
Despite reported sightings by Sparling and several others during the past few years, the last confirmed sighting of the bird was in northern Louisiana forests in the early 1940s, Turner says, and those forests have mostly disappeared because they were heavily logged during the first half of the 20th century. The wood was in high demand for fuel during World War II. "[This was] believed to be a classic case of people driving a large charismatic species to extinction by exploiting its habitat," he said.
Finding the ivory-billed woodpecker would be exciting and important in more ways than one. The black-and-white bird is beautiful, Turner says, and males look especially dramatic with a bright red crest on their heads. If it exists, it would be the largest woodpecker in the U.S. and the third largest in the world. It would be remarkable that the bird could survive for so many years without scientists knowing about it.
The woodpecker's existence could also motivate people to protect the remaining forest that the bird calls home, which in turn would protect "a whole host of other organisms living in that ecosystem," according to Turner. "If this bird could have hung on and still exists, it would surely say something about the integrity of life and its ability to overcome adversity."
Prachi Patel-Predd, Institute for Global Environmental Strategies