Wildlife biologists give genetics increasing role in species conservation.
Genetic fingerprints, they're not just for people anymore. They are creeping into the wild, helping biologists understand and conserve rare and endangered species.
As in humans, a little reveals a lot in this brave new genetic age. One hair follicle, feather, drop of blood, or fleck of skin contains enough DNA to identify individual animals, their species, sex, maternity, and paternity.
Essentially tagging animals without ever touching them, wildlife biologists are identifying populations at risk, their habits, habitat, social structures, and breeding patterns.
Even law enforcement is now using it to solve wildlife-related crime cases like poaching, and the illegal sale and transport of protected species. The National Fish and Wildlife Forensic Laboratory, the only full-service wildlife crime lab in the world, uses DNA analysis on 25 percent of the 1,000 cases it sees each year, says lab director Ken Goddard.
The field of conservation genetics is so new as to only be given a name in the past decade. No one was thinking about genetics and wildlife 11 years ago, says George Amato, director of the Conservation Genetics Program at the Wildlife Conservation Society in New York. "Now we can't keep up with requests for research."
In just the past few years, Mr. Amato's group has discovered two new species of deer in Southeast Asia and rediscovered one not seen for 60 years. They've assessed the genetic health of right whales - one of the most critically endangered marine mammals in the world - by comparing the DNA of century-old museum specimens with that of living whales.
And they've gained insight into the mysterious eastern lowland gorilla, a shy mammal that has historically eluded field biologists. Using DNA analysis, researchers collected naturally shed gorilla hairs in Kehuzi-Biega National Park in the Democratic Republic of Congo.
Lab results identified 65 individuals and confirmed that the eastern lowland gorilla is a distinct subspecies, different from the western lowland gorilla and the mountain gorilla. Applying the data, researchers then mapped the eastern lowland gorilla's genetic distribution, which showed that the park's narrow middle, where people lived, created a gate of sorts, stopping the gorillas from moving from one side to the other. Researchers recommended restricting human activity and/or expanding the park's middle to open the flow.
"This is the biggest revolution in wildlife management since radio telemetry, especially for these secretive forest creatures that are so difficult to monitor," says Katherine Kendall, a research ecologist at US Geological Survey, who is heading the Greater Glacier Area Bear DNA Project.
Not to mention those creatures that weigh 300 to 800 pounds and are sometimes dangerous. In the past, biologists sedated and collared grizzly bears, flew overhead to count them, and even positioned cameras with trip lines to get them on film. Kendall's project instead systematically collected grizzly-bear hair samples in the "Greater Glacier Area," a 2 million-acre grizzly recovery area in the Western US.
Noninvasive genetic techniques are less stressful, less disruptive, and more efficient, Kendall says. "Using live capture, we'd be lucky to capture 25 bears in a year," she says. But over a 12-week period in 1998, she and colleagues collected enough hair to identify 212 individual grizzly bears.
Kendall estimates that 350 bears reside in the study area, about 150 more than previously thought.
"This is encouraging news," she says. "We can quibble about whether 350 is an accurate population count, but I know I have 212 bears that are positively different."
Across the border in British Columbia, Canada, researchers are studying the DNA of 900 grizzly bears for paternity, pedigree, and inter-population analysis. By looking at individual bears, their parents, and their offspring, they can develop a picture of the grizzly bears' dispersal and movement.
An estimated 10,000 to 13,000 grizzlies reside in British Columbia. Highways running east and west cut through grizzly-bear habitat. With DNA data, researchers hope to learn how much highways impact the bears.
Genetics won't completely replace traditional field-research methods, biologists say. "DNA data doesn't make sense out of context. It needs field research to make sense," Amato says. It also doesn't reveal data in assessing a population's health, like age and litter sizes.
But conservation geneticists believe DNA will provide the core of most conservation efforts. Most, if not all, recovery plans for threatened and endangered species now include genetic guidelines or information, says Matt Powell, a fisheries geneticist at the University of Idaho. The Endangered Species Act includes language for listing "distinct population segments" as endangered.
Take the case of the sockeye salmon in Idaho: One type lives year-round in a lake, another migrates to the ocean. They look alike and live and breed in the same lake. The first is doing well, while the other is endangered. "The only way you can tell them apart is by testing them genetically," Powell says.
"We are at a stage in our history where lots of man-caused extinctions will soon take place," Powell says. "Genetic information is fundamental to the long-term recovery and conservation of these plants and animals."
(c) Copyright 2000. The Christian Science Publishing Society