Fuzz: When Nature Breaks the Law

On the USDA’s Federal Noxious Weeds List are several plants with lethal phytotoxins, or plant poisons. Abrus precatorius, commonly known as rosary pea or jequirity bean, contains a phytotoxin called abrin, of which possession over a gram is illegal (153). The dried beans are often used as jewelry beads. The plant is commonly used in suicide attempts in southern India, though the beans mostly cause gastric distress.

Castor beans contain ricin, which is a better-known toxin. The plants and seeds are widely and legally available from nurseries throughout the US. Castor oil, a diarrhetic, does not contain ricin, and studies on mice show that swallowing pure ricin is only lethal in large amounts, whereas chewing the seeds delivers the ricin more effectively (155). Even more effective is ricin delivered via injection, in which case much less than a gram is required. This method was used by a spy to assassinate a Bulgarian dissident in 1978 (156). Reported killings with abrin go back to the 1800s, when people would make and dry abrin paste into little needles called sutaris. Modern terrorist plots have speculated about adding ricin or abrin to normal explosives, turning the shrapnel into tiny, poison needles (157). However, bombs are more likely to burn up the toxin than disperse it, as it takes specialized equipment to turn them into dangerous fine aerosols instead of droplets (157).

The author learns that some common garden and household plants, from kidney beans to azaleas, have high levels of toxicity. Plants evolved poisons as a defense against being eaten since they cannot move. Ricin gets more attention as a phytotoxin, but it is not the most lethal, nor the most commonly available. Part of the reason ricin and abrin are of note to anti-terrorism agencies is that they can bind to any cell in the body, while many other phytotoxins specialize in only certain cells. Because of its listing on the Select Agents and Toxins list, ricin can be hard for researchers to obtain, but the author discovered a website offering to sell large amounts of it. The FBI monitors such sites but told the author that the website she found was more likely a money-making scam than a legitimate black-market poison vendor (161). The worry about ricin is not that terrorists will aerosolize it or put it in food or water supplies but that someone will modify a contagious virus with it (161).

The US military has experimented with toxins in warfare against humans, too, including trying ricin in various ways during World War II. However, the efforts were unsuccessful, so the ricin was given to laboratories to find ways to combat rats (162). In World War II, the ingredients for rat poisons were needed for the war effort, so rat problems increased greatly. The National Defense Research Committee got involved in testing ricin, sarin, and other toxins on rats. The most effective one was called 1080, or TWS, a fluoroacetate that had been used in rural Africa (164). The problem with 1080 is that dogs are more sensitive to it than rats, so if they try to eat the dead rats, the dogs die, too. The government agencies decided it could be used as a predacide, a poison to kill predators, for ranchers to use against coyotes. However, coyotes vomited up the undigested poison that dogs would then eat. Instead, an emetic (vomit-inducer) was added to the rat poison in case dogs ingested it, because rats cannot vomit (166).

The development of the toxin DRC-1339 initially came as a boon to sunflower farmers, who were losing a percentage of their crops to blackbirds, cowbirds, and grackles (166). Other methods of deterring the birds, such as creating hybrids with seeds that had less oil and were harder for birds to remove, were unsuccessful, as farmers grow sunflowers largely for the oil. In 2006, when Frito-Lay began frying its potato chips in sunflower oil, the National Sunflower Association (NSA) increased the allowances for blackbird killings. However, earlier reports from the National Wildlife Research Center (NWRC) showed that DRC-1339 was also killing many non-target species, including pheasants and cardinals (167). The amount of birds killed had a negligible effect on the pest problem. Decades earlier, contributors to the NSA’s magazine wrote about nonlethal methods of mitigating crop loss from birds (168).

Until the 1980s, the concept of conservation in the United States meant protecting wildlife for hunting and fishing. The practice of “crow-bombing” was overseen by game wardens and wildlife commissioners throughout the United States to kill off the birds that were eating duck eggs, thus reducing the number of mature ducks available to hunters. Farmers also waged war against flocking birds with the approval of government agencies. In the oral histories of the NWRC, the author finds reports of a government wildlife bounty hunter who realized, during the course of his career, that the killings were ineffective due to the phenomenon of “compensatory reproduction” (173). Essentially, when part of a population is destroyed, there are more resources for the remaining population, which will then increase in numbers again. Estimates on controlling coyote populations suggest that a staggering 60 percent of coyotes would have to be killed every year to have any sort of significant impact on their numbers (174).

The numbers in reports on farm-pillaging by birds are often faulty. The methods farmers use to estimate the size of bird populations are also inaccurate or exaggerated to secure funds for pest control, and the amount of crop loss is typically no more than what would be lost by a combine harvester (174). Additionally, examinations of the stomach contents of pest birds show that blackbirds consume a significant amount of insects and weed seeds, thus providing a service to the farmer (175). Though roost bombing has stopped, lethal methods of bird control have not, moving on to using chemicals.

In the 1930s, machine gunners carried out an operation to kill emus in Western Australia, but the number of dead birds proved disappointing. After six days, the government scrapped the mission (176). During and after World War II, the US naval base on Midway Atoll tried different methods to remove albatrosses (called “gooney birds”), which caused damage to plane engines. At first, the military tried clubbing them, then harassed the birds with sounds, bad smells, and radar beams (180). They attempted translocation, but the majority of the albatrosses flew back to Midway to nest. After clubbings resumed and 21,000 albatrosses were killed, the problem remained, and the morale of sailors doing the clubbing was low (182). Modifying the land around Midway, playing distress calls, and developing a repellent all proved unsuccessful. The sailors’ wives on the base managed to shoo the birds away with tablecloths, so a researcher suggested trying to install flat, colorful panels around the base, but the Navy did not take up the proposal (183). Though the bird-strike problem continued at Midway until the base closed in 1993, no planes crashed or personnel died from the issue. The base is now the Midway Atoll National Wildlife Refuge (185).