The USDA wants to poison 2 million blackbirds a year to save sunflower crops in the Upper Midwest. Trouble is, the department's own data suggest the plan won't work.
by Ted Williams
It is difficult for swamp Yankees to write objectively about how best to kill red-winged blackbirds for the alleged benefit of agribusiness, particularly when the plan reeks of politics. In our circles, the arrival of the males in late February, or sometimes early March, is important news and no less cause for celebration than the first tentative chimes of spring peepers a few weeks later. In the Northeast, as in most of the nation, redwings serve as palace guards to ancient snappers and their courts of lesser turtles, frogs, muskrats, ducks, herons, pickerel, and trout. Few are the days when, sprung from work or winter, I am not gladdened by at least one redwing, fluttering up from her nest, riding a bobbing cattail, or flashing his scarlet epaulets and shouting "Okareeee!" into the sweet wind.
The scene is different in the Dakotas and western Minnesota, where the arrival of redwings, especially southbound in late summer, elicits only bile. Here, some 40 million strong, they waft across the smooth horizon like unscrubbed coal smoke. Probably, these flights are the nearest thing anyone will ever see to the movement of passenger pigeons. In fact, some scientists speculate that it was the demise of the passenger pigeon, also a ground gleaner, that enabled the irruption of redwings. Assisting in this irruption, of course, have been vast plantations of rice, corn, wheat, and sunflowers.
Sunflower seeds, especially the black kind, half oil, are the most succulent, nutritious food available to redwings. Occasionally assisted by a few yellow-headed blackbirds and common grackles, they will descend like hail on a 50-acre sunflower field, consuming a third, half, or all of the crop, and like hail, there is no predicting where they'll hit next. Most of America's 10,000 sunflower growers are in the Dakotas and Minnesota, where they produce 80 percent of the nation's crop--mostly for oil, some for wild-bird seed, and some for human "confection" (the striped, salted kind one bites and spits). Estimates of blackbird damage to sunflowers vary from about $10 million to $20 million a year, and this doesn't include the enormous cost of trying to drive them away. The loss sounds trivial when one considers that the annual worth of the nation's sunflower crop approaches half a billion dollars, but the damage is not evenly distributed. About 500 growers lose more than a quarter of their crop in any given year.
So the wildlife-damage-control section of the U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS) is proposing to poison 2 million blackbirds a year, for at least three years, during their spring migration. APHIS has no reason to believe that this will provide relief for sunflower growers, but the agency has been facing withering political pressure from the growers, who want to see redwing carcasses and who speak through the National Sunflower Association (a funder of APHIS research).
APHIS has found that the damage is caused by local nesting birds but that something like 70 percent of the spring migrants continue on to Canada. Such scientific subtleties, however, are lost on the growers. Scott Nelson, who chaired the National Sunflower Association until July and who has been raising sunflowers in Lakota, North Dakota, for 17 years, puts it this way: "If you kill one blackbird, I do know that that one will not eat your sunflowers." Blackbird control--as it has been practiced on a limited, experimental basis in the past and as it is being proposed on a large-scale "operational" basis for the future--provides a fine example of how a good, effective agency that employs excellent scientists can be coerced by special interests into chasing its tail. There are, however, at least two alternatives to killing blackbirds that promise genuine relief to sunflower growers.
Any critique of APHIS needs to be prefaced with some facts about the agency--facts a large element of the American public doesn't want to know. Herewith, some of the most important.
• Most animal-damage control done by APHIS is nonlethal.
• Most animal-damage control done by APHIS is innovative and effective.
• A great deal of the agency's work is directed at endangered-species recovery. There have been stunning successes.
• APHIS doesn't casually festoon the American landscape with biocides. In controlled experiments it has been killing blackbirds with rice laced with DRC-1339, a short-lived, rapidly metabolized poison with a long track record of effectiveness, safety, and selectivity. For 30 years DRC-1339 has been successfully used on ravens, crows, pigeons, starlings, cowbirds, grackles, red-winged blackbirds, magpies, and sundry gulls. Because it is quickly metabolized, the possibility of secondary poisoning (in which a bird or mammal dies from eating a stricken blackbird) is remote. Direct mortality of nontargets is probably inevitable but, in this case at least, utterly unacceptable in any quantity because the proposed program is basically a political gesture that is unlikely to succeed. APHIS minimizes the threat by 1) using caged redwings to decoy wild ones; 2) "pre-baiting" an area with unpoisoned rice, so that when the hot bait goes out, the birds stream in and consume huge amounts, leaving little for nontargets; and 3) keeping baited areas small. To annually take out 2 million blackbirds, APHIS would have to bait a maximum of only 50 acres a year and more likely less than 30.
• Finally, one might argue that much of the experimental blackbird control was necessary, if only to prove what doesn't work. It also forestalled vigilante action of the sort that occurred near Mascoutah, Illinois, in October 1999, when a wheat farmer sought to solve his blackbird problem by illegally dousing 12 acres with carbofuran, a poison so deadly to birds that it kills scavengers that eat the victims and even scavengers that eat the scavengers. He killed 27,000 birds, not all of them redwings, then paid a $5,000 fine for violating the Migratory Bird Treaty Act and misusing a pesticide. What's more, without the failed experiments, the scene might be much worse in the Dakotas, where even now there are reports of frustrated sunflower growers poisoning wetlands with crankcase oil and opening pressurized tanks of fertilizer--highly toxic and thoroughly nonselective--upwind of wetlands where redwings roost.
It's not hard to understand why Scott Nelson wants to kill all the blackbirds he sees, including Canada's. Last year he planted 1,500 acres in sunflowers; this year, because of blackbirds, he planted only 500. "We've had nine years of incredibly wet weather, so now every little dimple is standing in cattails," he says. "On top of that a lot of the land here is under easement to the Fish and Wildlife Service, which prevents it from being drained and farmed as it should be. I've been forced to take nearly all the fields near cattails out of production. Last year on half our crop we lost 90 percent to blackbirds, and on the other half we lost 30 percent to 50 percent." When I asked how much that came to, he started punching a calculator. "The number's so big I hate to even see it," he muttered. "Probably about $200,000."
APHIS and the growers have tried all manner of hazing methods. Propane cannons triggered by electric timers sometimes scare redwings; more often they provide perches. Growers attempt to frighten redwings with firecrackers, occasionally burning up their fields in the process. They buzz redwings with airplanes, blast them with sirens, strafe them with shotguns, and frighten them with a sparsely applied pesticide called Avitrol, which makes the few that ingest it squawk and flap around before it kills them. One grower uses hawk kites suspended from helium balloons. Another, having equipped his helicopter with a tape deck and amplifier, hovers over his sunflowers playing Willie Nelson Live in Concert. Even APHIS admits that success at nonlethal redwing control means driving the birds to another field, hopefully the neighbor's.
So lethal control has a special allure. APHIS is proceeding with an environmental-impact study (EIS) in pursuit of its plan to poison 2 million redwings annually for at least three years during the spring migration. As early as 1991, however, the agency published a paper stating that spring baiting probably wouldn't protect sunflowers because the birds disperse widely during breeding season.
In 1993 and 1994 APHIS had tried poisoning blackbirds during the fall migration, when the birds were doing the damage, which would seem a more direct and efficient approach. But in 1996 it published a paper concluding that fall baiting doesn't work. The reason: Blackbirds don't like rice (or any other bait) nearly so well as sunflower seeds. Why should they pick up bad hamburger on the ground when they can get prime rib eye on the sagging seedheads? Then, in 1998, under fierce pressure from powerful, articulate, well-organized, ignorant growers, the agency extended fall baiting to 460 fields.
APHIS argues passionately, though not very convincingly, that it wasn't posturing for the sunflower industry. The U.S. Fish and Wildlife Service--a traditionally meek outfit that shuns confrontation of any sort--loudly says that posturing was precisely what APHIS was doing, and when Fish and Wildlife shouts, the public better listen. In fact, it has been attacking APHIS with such vitriol that it now tries to have only one agency official talk to the press about blackbird control--Larry Gamble, environmental contaminants coordinator for the mountain-prairie region. "Fall baiting was pure politics," he told me. "We received the environmental assessment the day APHIS started baiting. The researchers would have done a better job, but they were rushed by their superiors. They were supposed to collect data; they didn't. They didn't follow the parts of the label intended to protect nontarget birds [which forbids the use of DRC-1339 when nontargets are eating unpoisoned bait put out to condition blackbirds]. They were supposed to document the number of blackbirds at the bait sites, and they said they'd seen 2,000. Someone asked, 'You only saw that many at each?' And they kind of lowered their heads and said, 'No, that was the total number we counted on all 460 sites.' Then they said the 1998 fall-baiting study was too small and they needed a bigger one. So we acquiesced and gave them the permit because we knew the results would be no different." Fall baiting in 1999 and 2000, which APHIS decided to scale way back, also proved utterly ineffective. Now it has given up on fall baiting, and even the sunflower growers agree it doesn't work.
The spring baiting APHIS is now proposing is a very different concept, in which northbound birds are to be poisoned as they funnel through a narrow migration corridor in South Dakota. APHIS had been doing spring baiting, too--also on a small-scale, experimental basis--from 1994 to 1999. In spring redwings don't have the luxury of ripe sunflower seeds, so poisoned rice looks a whole lot better to them. But spring baiting has its own set of daunting, maybe insurmountable, challenges. For one thing, the Migratory Bird Treaty Act appears not to allow killing birds six months before they depredate. So APHIS may need a special depredation permit from the Fish and Wildlife Service, which, at this writing, seems unlikely to be coughed up. For another, a large percentage of the birds moving through the Dakotas in the spring don't eat sunflower seeds in the fall.
"Spring baiting is more about convenience," says Gamble. "It's another case of APHIS ignoring its own research. They studied these roosts, while the males were migrating, marked the birds with fluorescent paint. It turned out that 70 percent of them nested in Canada, but the damage is caused by local nesting birds. APHIS wants to target females [which migrate after the males]. They assume that the females from these roosts are going to nest in the Dakotas, but there's absolutely no data. During the last four years of [experimental] spring baiting, the nesting population increased by 33 percent, but damage remained the same. So it doesn't appear that nesting population size is related to damage. We've asked them about this and haven't received a response. . . . I'm troubled by a federal agency selling this program to farmers as a tool that works when their own data shows it doesn't."
When APHIS requested a scientific collector's permit under the Migratory Bird Treaty Act to kill 2 million blackbirds in the spring of 2000, supposedly as an expanded study, the Fish and Wildlife Service denied the permit. APHIS responded to this affront by abandoning the scientific-research approach and instead seeking a large-scale, operational program via an EIS.
The Fish and Wildlife Service asked scientists at the U.S. Geological Survey's Northern Prairie Wildlife Research Center, Colorado State University, and New Mexico State University to review the spring-baiting proposal. The scientists, too, had major problems with it.
But APHIS defends its position. "There's a difference between a researcher who has worked in this field for 20 years and outside reviewing scientists who are not very familiar with migration patterns of blackbirds," remarked George Linz, APHIS's proj-ect leader for blackbird research on the Great Plains, when I read him some of the comments of his critics. "I do not 'ignore' any data, or I would not be the project leader of this very tough problem. It's the interpretation of the data where we differ." Linz is a superb scientist with a well-earned reputation for professionalism and honesty. Moreover, he's a member of every major bird group, as well as Audubon, and his farm is a forest of nest boxes. He likes wildlife, but he understands it, too, and that takes considerably more doing. When I asked him if political pressure had pushed his superiors into fall and spring blackbird baiting against their better judgment, he said this: "Well, every agency has a special-interest group it responds to. The Fish and Wildlife Service has theirs. Ours is agriculture. I'll let it go at that."
Linz is a researcher. Researchers love to do research; setting time limits, using it to frame management, and making decisions about whether or not to proceed with major wildlife-damage-control programs is up to someone else.
In addition to understanding the good work APHIS does, environmentalists need to perceive its failures in the correct context. Bending with the political breeze may not be excusable for a resource agency, but it is universal. The Fish and Wildlife Service, formerly the parent of APHIS's wildlife-damage-control section, is no less guilty. For instance, in 1996 it called in APHIS to clear a 125-acre beachhead with DRC-1339 to help black skimmers, threatened piping plovers, and terns on gull-plagued, 7,600-acre Monomoy National Wildlife Refuge, at the elbow of Cape Cod. Before 1961 there had been no nesting gulls on the refuge; in 1995 there were 5,200 pairs of herring gulls and 7,350 pairs of greater black-backs. As requested, APHIS took out 15 percent of the gulls, killing no nontargets in the process. That year nesting pairs of common terns soared from 231 to 694, least terns from 28 to 103, roseate terns (endangered) from zero to 3, piping plovers from 14 to 20, and black skimmers from zero to 5. But the public tends not to distinguish between light-colored seabirds smaller than a bread box, valuing all equally, regardless of species or abundance. So badly did the Fish and Wildlife Service get beaten up by animal-rights advocates and even mainstream environmentalists that it quit using DRC-1339 at the refuge. Now, at enormous cost in man-hours, it harasses nesting gulls daily on 75 acres and punctures eggs on 50. While this works, too, resources desperately needed by wildlife are being siphoned off merely to appease ecological illiterates.
I am beginning to suspect that the travails of APHIS in the Upper Midwest are due not just to its own timidity but also to the simple fact that reducing damage to sunflowers by killing blackbirds is not practical, maybe not even possible. By contrast, protecting livestock from wolves in Minnesota is a piece of cake (see "Living With Wolves"). "Fifteen years ago farmers could handle 10 percent to 15 percent loss to blackbirds," says Larry Kleingartner, executive director of the National Sunflower Association. "But in today's economic environment, it's not in the cards. So they're going to other crops." Maybe that's just the way it has to be.
Still, there are measures that might help. The most promising--an alternative that will be listed in the EIS--is herbiciding more of the cattail monocultures blackbirds roost in, doubling treated areas from about 4,000 to 8,000 acres a year. Maybe even the 8,000 acres should be doubled. At something like $60 per acre, the program would be expensive but an infinitely better investment than spring baiting. "I'm a big believer in cattail reduction, because it addresses the problem at hand," says Linz. "The damage is in the fall, and it occurs because a lot of birds congregate in wetlands that have some water in them. The reason the program's in place is that we do think it disperses damage."
With about 750,000 acres of cattails in North Dakota alone, 8,000 or 16,000 acres wouldn't be missed, even if they were an ecological asset. But they aren't. What makes cattail reduction even more attractive is that at the same time it destroys redwing habitat, it restores lost biodiversity. Most of the cattails that provide roosts for redwings in the Upper Midwest are an invasive hybrid of the narrow-leafed variety, which moved east into the Dakotas about 60 years ago, and the native common cattail. The herbicide used--glyphosate--is relatively innocuous and used in low concentrations, posing little threat to other organisms. "We have no concerns about toxicity," comments Michael McEnroe, a biologist with the Fish and Wildlife Service's refuge division. In fact, the service has retained APHIS to use glyphosate on its own waterfowl production areas.
In one experiment APHIS found that 17 wetlands choked with cattail monocultures harbored 197 dabbling ducks and 6 diving ducks. During the two post-treatment years, those wetlands harbored 782 dabblers and 244 divers. In other wetlands, populations of six classes of invertebrates remained stable after herbiciding, but gastropods increased. The Fish and Wildlife Service did have some concerns about species that depend on thick cattail cover, mainly marsh wrens and rails, so on marshes that it doesn't control, it talked APHIS into leaving at least 30 percent of the cattails, thereby creating a mosaic of vegetation and open water not unlike the natural marshes of old. On its own marshes, the Fish and Wildlife Service welcomed blackbird control. "Fortunately, we've been able to partner with APHIS," declares Roger Hollevoet, district director of the Devils Lake Waterfowl Management District, in northeastern North Dakota. "We get free management that way--a good interspersion of cattails and open water. First we see a reduction in blackbirds. Then we start seeing many of the wading birds coming back, then waterfowl--both divers and dabblers--and, finally, bitterns, black-crowned night herons, great blues, and black terns. We might displace some marsh wrens and some sora and Virginia rails, but they still have plenty of habitat along the fringes."
In Venezuela, where dickcissels ravage crops of rice and sorghum, farmers had been getting no relief by poisoning the birds by the hundreds of thousands on their nocturnal roosts. Now, under a cooperative venture with the Venezuelan Audubon Society and several universities, they've agreed to hold off on the pesticides and try nonlethal alternatives. "There is no silver bullet," points out Alejandro Grajal, Audubon's vice-president for Latin America and the Caribbean. And most of the alternatives being tested wouldn't work on blackbirds. But one strategy--insurance--holds tremendous promise for sunflower growers. Like dickcissels, blackbirds touch down with no predictability, sparing most farmers in any given year but blitzing a few. While funding has yet to be procured, an insurance-style model is being set up in Venezuela in which the farmers' co-op, with the support of government and nongovernment organizations, would compensate farmers who suffer major losses. In our Upper Midwest, such a system would probably be far more cost-effective than trying to effect population control on superabundant blackbirds, especially if it were combined with aggressive cattail reduction.
After Audubon published a short piece on blackbird poisoning ("Bye-Bye Blackbirds"), a reader wrote us expressing dismay that he was "supporting this heinous behavior by Dakota farmers and the federal government" by buying "hundreds of pounds of sunflower seeds a year."
But I don't see anyone behaving heinously--just stupidly and cravenly. A national boycott, as the reader urged, would be ineffective because only a small fraction of the crop is sold as bird food. Instead, I suggest putting the same kind of pressure on APHIS that it gets from the National Sunflower Association. Under the EIS process, the agency is asking for your comments. Don't disappoint it.
Ted Williams has been baiting redwings longer than APHIS, but only with unpoisoned cracked corn, which he spreads on his lawn in late winter.
© 2001 NASI
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