A Goose on the Loose?
Every autumn, Dale VanderZanden eyes the skies above his Sauvie Island farm and wonders how many Canada geese will feed on his crops. Every year for the past 15 years, the number has gone up.
Ten times as many Canada geese spend the winter in Oregon as they did 20 years ago. Now instead of one subspecies of Canada goose, the dusky, there are seven. Now, instead of the 25,000 geese that wintered in Oregon, there are 250,000, an increase of 50,000 from last year.
And now farmers, wildlife officials, scientists and politicians are making changes in hopes of decreasing the soaring goose population. Farmers like VanderZanden and conservationists such as Jon Plissner, president of the Corvallis chapter of the Audubon Society, agree. "This is just too darn many geese," VanderZanden said, summing up the concern that Oregon's agriculture community has. The farmers' emerging winter ryegrass, carrot tops and winter wheat are some of the crops most prized by the hordes of geese. They descend in October and stay until April. The whole time, they feed. They feed despite farmers' efforts to scare them away with propane cannons, scarecrows or people on three-wheel vehicles, waving their arms. They're smart, VanderZanden said. Farmers have been saying that for the past decade, but now new technology, new research from Oregon State University and a new goose management plan are all aimed at finding ways to lessen the conflict between farmers and the geese who feed off their work.
Bob Jarvis, a professor of wildlife ecology at Oregon State University, has studied geese for 35 years. He said the goose boom that has become noticeable in the last 20 years actually began in the mid-50s. It extends to goose populations in all the flyways over North America. In the Midwest, for example, a skyrocketing population of snow geese is a major concern to Iowa farmers. Jarvis said the boom is a complex mix of human and natural causes:
- Agriculture provided winter feed for geese.
- Regulated hunting increased their survival.
- A long-term warming trend in the Arctic boosted hatchling survival in the nesting grounds of Canada and Alaska.
Most geese species in the Pacific Flyway-the migratory route that brings geese from Canada and Alaska into southwest Washington and western Oregon-were thriving. But two sub-species were in trouble.
Dusky Canada geese, the only species of migrating geese that historically wintered in Oregon, were among the victims of the devastating 1964 Alaska "Good Friday" earthquake. The 9.2-magnitude trembler was the worst recorded in North America. In addition to causing the deaths of 133 people, it raised the level of the traditional marshy nesting grounds of the dusky, eventually creating a more brushy environment that attracted predators such as foxes,
coyotes and other birds to prey on goose hatchlings.
The population of dusky increased to 25,000 by the mid-1970s because the drained Copper River Delta marsh in Alaska provided more nesting sites. But after the predators moved in, the number plummeted to less than 8,000 by 1984. Alarmed, wildlife officials ordered an emergency closure on goose hunting in 1984.
It wasn't just a love of the geese that prompted this action. Two powerful pieces of legislation require protection of geese: the 1916 Migratory Bird Treaty between the United States, Canada, Russia and Mexico, and the 1972 Endangered Species Act.
An international treaty is the highest form of law. And nobody wanted to see the far-reaching powers of the Endangered Species Act invoked if the dusky population continued its decline.
So the following year, a harvest quota of 300 dusky was established. Once hunters bagged 300 dusky, goose hunting was over for the season. Another subspecies of Canada geese-known as cackling Canada geese or cacklers for short-also hit a crisis population low about the same time. This goose, which makes a distinct cackling sound, was being threatened by the Yupik native people, who relied on its eggs as an important early-spring food source.
However, they also were being hunted enthusiastically in their California wintering grounds. As a result of this double hit, cackler numbers plummeted from 400,000 in the 1970s to 25,000 by 1985.
The native people and wildlife officials agreed to stop hunting cacklers along the length of their flyway. Then the cacklers made an unexpected change, too. Instead of flying to their traditional wintering grounds in Central California, they made the Willamette Valley their winter feeding ground. Soon, cackler numbers exploded. The population increased by14 percent every year between 1986 and 1995, despite renewed hunting. U.S. Fish and Wildlife Service's figures counted more than 200,000 cacklers in 1997. Taverner's, Aleutian, Lesser and Vancouver Canada geese also moved into Oregon for their winter and thrived along with the native year-round population of western Canada geese.
That was too much of a good thing, according to the Farm Bureaus of Oregon and Washington. Not long ago, they were poised to file suit against state and federal fish and wildlife agencies. And farmers say they are paying for the protection of the dusky and the cackler geese in lost harvest yield and in the cost of having to twice fertilize, weed and harvest goose-grazed fields.
But for the first time in a long time, farmers and game managers worked together to come up with a solution. The Farm Bureaus of Oregon and Washington, along with the Oregon and Washington Departments of Fish and Wildlife and the U.S. Fish and Wildlife Service, adopted a new nine-part plan aimed at solving the goose overpopulation problem. It's called "The Northwest Oregon/Southwest Washington Canada Goose Agricultural Depredation Control Plan."
A key factor in that plan employs science, goose savvy and satellite technology to find a way to put real dollar figures to the winter crop losses that affect farmers such as VanderZanden. "It's approaching between $70,000 to $100,000 a year," VanderZanden said. But his estimates are anecdotal, based on past yields and some guesswork. In 1995, the Oregon Agricultural Legal Foundation commissioned OSU's Department of Rangeland Resources to find a method of measuring goose grazing on farmland.
Such data has been lacking, said Christina Smith, the regional manager for the Oregon Farm Bureau. In the past, the losses could be attributed to other factors such as flooding or bad farm practices. But having a method that could give each farmer a way to accurately measure damage from goose grazing also could give them some clout.
"The Northwest Oregon/Southwest Washington Canada Goose Agricultural Depredation Control Plan" calls for cutting the total overwintering population of Canada geese by 20 percent by 2002, from the current 250,000 to about 200,000. As part of that same plan, VanderZanden's winter wheat fields are now serving as test plots for a two-year research project headed by Michael Borman, an extension specialist in OSU's rangeland resources department. Douglas Johnson, a rangeland resources professor who's an expert in a new satellite mapping technology, is a co-leader of the study.
Borman is an expert in grazing. He has advised Gov. John Kitzhaber's project on salmon recovery about the streamside grazing habits of cattle. Now it is geese. Borman and graduate research assistant Mounir Louhaichi of Tunisia put up a total of 36 chickenwire "goose exclosures," each 6 by 13 meters, in four of VanderZanden's fields last year, and 30 similar fenced-off areas in three fields this year. Although they are voracious feeders on the tender grasses, clovers and carrot tops that appear in late winter, geese strictly adhere to a basic motto of goose survival: Better be safe than supper.
So the geese avoid the chickenwire exclosures just as they avoid feeding near fencelines, roads or trees that could harbor predators. By capitalizing on this well-documented tendency of geese, the research project now has the basis for a comparison: The winter wheat within the chicken wire demonstrates how the entire field might have grown if geese had not grazed there.
Johnson next mapped the test fields on a grid using both aerial photography and state-of-the-art satellite mapping known as Global Positioning System (GPS) technology.
Accurate to within a meter, the GPS system produces a reliable map grid of the test fields. A harvester equipped with another GPS satellite system will enable comparisons of the yields harvested from the patches where the geese did not graze compared to the goose-grazed portions. Although Borman points out that the results of this research project will be applicable only to VanderZanden's wheat fields, the same method could work on other crops in other fields.
In its strictest sense, it is a way for farmers to document which crops didn't grow as they would have without geese grazing, Borman said in February, as he stood in one of VanderZanden's test fields.
It had been several weeks since geese grazed in this particular field. Rain had washed away the goose droppings. The wheat-which resembles crabgrass at this stage-was about 4 inches high.
Look at this without the exclosure, and you'd never know geese were in here. But look in the geese-shunned chickenwire areas and you see lush green wheat about 6 inches tall.
Well aware of the politically charged nature of the controversy, Borman explains that his research is not designed to provide ammunition to shoot geese from the sky.
"It could be that it shows the damage from geese grazing isn't as bad as everyone thought," he said.
In addition to looking at hard figures, the wildlife managers are also taking a harder line with regard to hunting the geese, including tolerating some accidental shooting of duskys. For example, the agencies tried a special hunt last winter aimed specifically at reducing the population of non-dusky subspecies. After first educating hunters to identify the dusky, they issued goose-hunting permits to 1,500 hunters who bagged 9,000 geese of all kinds, including more than 200 dusky.
Farmers thought the hunt was too little, too late.
"It didn't make a bit of difference," VanderZanden said. More drastic steps also are being taken by the wildlife agencies, said Brad Bales, migratory game manager for the Oregon Department of Fish and Wildlife.
The U.S. Fish and Wildlife Service recently issued the first kill permit for geese in 13 years to a Corvallis farmer. The permit allows the farmer to take up to 20 geese on his property as part of his continuing hazing efforts. And the farmers have managed to bring some high-powered attention to their plight.
Addressing Oregon farmers in late January, Sen. Gordon Smith, R-Ore., vowed to help seek a federal solution to this problem. He indicated that a solution might require an act of Congress to change the Endangered Species Act to allow the increased hunting of the dusky. But any action toward that direction is likely to stir the involvement of environmental groups that have been staying out of the geese-glut conflict between farmers and wildlife officials.
Sara Vickerman, director of the West Coast office of Defenders of Wildlife said her organization has no official position on increased hunting and has some sympathy for farmers. Neither does the National Audubon Society nor the Wildlife Federation. Vickerman said all of them likely would oppose any management plan that weakened the Endangered Species Act and allowed open season on the dusky Canada goose.
VanderZanden said that a wholesale slaughter isn't what farmers want, either. They want to return to some form of peaceful co-existence, a balance between the needs of the geese and the needs of the farmer.
"I like geese," VanderZanden said. "But there are just too darn many of them."