Introduction

In the European Union farm landscapes are being recognized for their potential to support long-term biodiversity if managed in an environmentally sensitive way. What can be done in the United States to sustain diverse wildlife populations wherever planting takes place?

RCC's 1998 Wildlife, Pesticides and People Conference showed the hazards to wildlife from powerful chemical pesticides. Dr. Julie Ewald described how damage to plants and insects from repeated herbicide applications had contributed to partridge population declines. Dr. Gary Nabhan showed the dependency of desert plants on pollinating insects and how insecticides drifting from farm fields could devastate rare night-blooming cacti through killing off native pollinators.

Many scientists stressed that in ecological terms the least conspicuous organisms are frequently the very ones on which the web of life most depends. As we gain understanding of our own need for ecosystem services, and the fact that successful ecosystems require an array of life forms, we develop greater respect for those organisms considered by some to be lowly and simple such as water fleas, oysters, mycorrhizal fungi and bacteria (see RCC's Source of Wonder, Source of Strength - Our Wildlife Workforce).

Most Conference speakers advocated safeguarding our natural resources by reducing pesticide use. Distressingly, USDA records show that chemical pesticide applications have increased, not decreased during the recent past (IPM/Pesticide Paradox). Estimated pesticide-related bird losses have increased as well.

Still there is hope. Recent data show that farmers from Pennsylvania, Maryland, Florida, Arizona and Indonesia have successfully reduced their chemical pesticide use while maintaining crop production and incidentally providing some benefits to wildlife (see section #8, Reducing Chemical Pesticides Use in Agriculture). These encouraging developments might go on to bear fruit if advocates for birds, bats, fish, marine mammals, butterflies and others call for ecologically responsible methods wherever planting takes place.

Conference Summary, Part II concludes the review of our 1998 Wildlife, Pesticides and People Conference. Subjects reviewed and their presenters are listed below. Updates accompany some of the reviews.

Presentation texts are available from RCC for 1-A, 1-B, 1-C, 2, 3, 5, 6, 7, 8; and Conference Summary, Part I is available on our website.

( 1 ) Pesticide Regulations and Wildlife

Overview

Wildlife are the organisms most vulnerable to pesticide toxicity and most exposed to chemical pesticides on a daily basis, yet they are the least sheltered from these hazards. The 1996 Food Quality Protection Act (FQPA) regulations, intended to safeguard children from pesticides, do provide some indirect benefits to wildlife but this is not their primary purpose (as explained in section 1-A).

EPA-mandated studies for the scientific assessment of pesticides' hazards to wildlife fail to give a complete picture. Final decisions on the assessment of pesticides' risks to wildlife are made not by EPA scientists but by EPA managers under a vague and subjective risk/benefit standard.

Migratory birds are supposed to be preserved under the Migratory Bird Treaty Act (as discussed in section 1-C) and individuals of the endangered or listed species (explained in section 1-B) are entitled to special preservation under the Endangered Species Act. EPA spokespersons have declared that birds are the wildlife group designated to receive the highest Agency protection from pesticide harm.

Nevertheless, Dr. Pimentel's estimated direct losses of birds from pesticides continues to rise and is now at 72 million birds per year. Our nation's overall legislative record of bird protection from pesticides is dubious and protection of other wildlife is even more doubtful.

( 1a ) EPA's Evaluation of Pesticides for Wildlife Toxicity

In 1996, a new federal law, the Food Quality Protection Act (FQPA), reflecting the nation's greater concern for child safety, imposed stricter standards on EPA's pesticide risk assessment procedures for human beings. Now risk assessment standards give humans more protection from pesticides than they give to wildlife.

As described by Mr. Merenda of the EPA the contrast is clear: the human health risks, "[from pesticides] must meet an absolute standard of 'reasonable certainty of no harm,' while ecological [wildlife] risks must be balanced against the benefits of using the pesticide."

Another way to characterize the risk evaluation standard for wildlife is; "[pesticide use] will not pose an unreasonable risk to the environment" (Joseph Merenda). The FQPA at times provides some protection for wildlife, but indirectly.

Recently, EPA has taken steps to improve evaluation of pesticides' effects on the environment through collecting information from the Ecological Incident Information System and the Pesticide Ecological Database as well as implementing a new program with the acronym ECOFRAM. Information collection and new paradigms notwithstanding, the final decision about how well wildlife can be protected from an individual pesticide remains, not from EPA's scientific reviewers, but with EPA's managers working under the vague and subjective 'risk balanced against benefit' standard previously described.

Examples of FQPA providing greater protection for wildlife while safeguarding children are pesticide cancellations. Household uses of the neurotoxic organophosphates chlorpyrifos and diazinon are being phased out as the result of actions initiated by EPA Administrator Carol Browner under FQPA. Birds, beneficial insects and aquatic organisms among those most adversely affected by contact with these potent nerve toxins will benefit through their removal from the homeowner market. Some agricultural uses for both organophosphates are still permitted and represent continuing dangers for wildlife.

In the 1980s EPA made a controversial decision to no longer require field-testing of pesticides prior to marketing. Such tests might well have detected ecological impacts such as the contamination of plant nectar with the insecticide imidacloprid (discussed under topic #3, Insecticides' New Modes of Action). Some effects have been discovered through the Ecological Incident Information System after pesticide products are already on the market -- too late to prevent wildlife losses.

Birds, Pesticides and Regulations

Although migratory birds are not the most vulnerable to pesticide toxicity, they are closer to the public eye (aided by binoculars) and dearer to the public heart than most other wildlife. EPA claims to have designated birds for greater protection from pesticides.

Support for this assertion is EPA's recent refusal to register the insecticide chlorphenopyr due to its adverse effects on birds. In this case public input also played a role in the Agency's decision. EPA's record of wildlife protection falters when it continues to permit use of the highly toxic organophosphates and carbamates such as fenthion, carbofuran and others. In addition, the Agency has failed to seriously evaluate indirect effects and low level exposures of birds to pesticides.

According to one wildlife toxicologist "'safe' pesticides are driving birds to extinction," (Dr. R. O'Connor). The Agency's record has disappointed Canadian Wildlife Toxicologist Dr. Pierre Mineau and other scientists who have investigated avian health issues. As if to confirm their concerns, the estimated direct losses of birds from pesticides by Dr. Pimentel has risen from 67 million in 1998 to 72 million in 2001.

( 1b ) Endangered Species and Pesticides

EPA is required by the Endangered Species Act (ESA) to avoid jeopardizing the continued existence of federally defined endangered or threatened wild species. Those designated as endangered, also known as listed species, are to be given the highest level of protection from pesticides of any wildlife. Listed wildlife are to be protected as individuals, not populations, and their habitat is to be protected as well.

In addition to the direct effects on listed species, EPA is required to evaluate the indirect effects of pesticides, such as hazards to host organisms for developing phases of listed individuals, hazards to pollinators of listed plants, and hazards to food sources for listed species. For these indirect effects it is sufficient to protect populations rather than individuals.

The most notable EPA action protecting endangered species occurred in 1972 with the banning of DDT. However, listed species still need the Agency's protection from chemical hazards. For example, the insecticide carbofuran has killed a number of Bald Eagles when applied according to the label and it is still registered for use. A recent lawsuit by environmentalists seeks better EPA protection of salmon, a listed species, from levels of the insecticide diazinon too low to be lethal but able to damage the salmons' ability to avoid predation and to find the streams of their birth through their legendary homing ability.

EPA's endangered species program continues to be hampered by lack of funding and other hindrances.

( 1c ) The Migratory Bird Treaty Act and Pesticides

The Migratory Bird Treaty Act (MBTA), a law protecting migratory birds, is "...one of the most important Federal statutes for birds native to North America and other parts of the world" (Dr. Jewell Bennett). Under this law the killing of migratory birds with pesticides can be considered a violation even if the intent was not to do so and the pesticide was being used according to the label.

The deliberate misuse of a pesticide to kill birds would also be a violation of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) as well as the MBTA.

Individuals and companies have been prosecuted under the MBTA for killing birds with pesticides. The MBTA is administered by the Fish and Wildlife Service. As described in RCC's brochure "A Nature Lover's Alert" an Oak Brook, Illinois lawn care company was fined for being responsible in the deaths of 47 mallard ducks after they legally applied diazinon to the turf of a condominium in Indianapolis. They were fined $4,700 and found guilty of a misdemeanor under the Migratory Bird Treaty Act.

In another example of an MBTA violation, a paper company had used an EPA registered avicide product containing the organophosphate insecticide, fenthion to kill problem starlings in 1997. Within days of the application, a red-tailed hawk and a great horned owl were fatally poisoned after consuming poisoned starlings. Although the use of fenthion had been legal where the starlings were concerned, the killing of the protected birds feeding on the starlings violated the MBTA and the company was charged.

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( 2 ) Swainson's Hawk and Pesticides

Swainson's hawks spend spring and summer in western North America where they feed on rodents, birds and reptiles. During the northern winter (or austral summer) they migrate to Argentina's rich grassland habitat where thousands of hawks become insect-eaters. In the past they shared the pampas pastures with grazing cattle. When the agricultural crops of soybean, sunflower, corn, and alfalfa replaced cattle, the hawks fed on grasshoppers and other insects infesting the fields.

An Argentinean farmer first reported the killing of a number of Swainson's hawks in 1995, after the insecticide monocrotophos was sprayed on sunflowers by a neighbor to control grasshoppers. This highly toxic organophosphate had been withdrawn from use in the U.S. in the late 1980s. Because it was not officially banned it did not raise alerts as to its inherent wildlife toxicity and it continued to be used around the world.

Thousands more hawk deaths occurred in the next two years setting the stage for scientists from Argentina, the U.S. and Canada, as well as environmentalists and multinational corporations, to join forces in an effort to prevent such disasters from happening in the future.

As a consequence, one company withdrew its monocrotophos-containing products worldwide (accounting for less than 20% of the world's supply), an effort was made to establish a way of tracking incident reports internationally, and a dialogue was started on pesticide use and migratory bird welfare among scientists.

RCC Update: As a result of this focus, the highly toxic monocrotophos is, as of 2001, withdrawn from the markets of Argentina and Australia. This action to protect migratory birds is an inspiring tribute to concerned farmers, dedicated wildlife professionals and caring individuals from the industry. This cooperation should be taking place in other parts of the world where unfortunately monocrotophos and other pesticides like it are still available to poison birds and other wildlife.

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( 3 ) Pesticides and Marine Mammals

Organochlorine pesticides in combination with other contaminants are routinely found in the tissues of marine mammals such as bottlenose dolphins, Baikal seals, harbor seals, striped dolphins and Beluga whales. Certain contaminants can be mobilized and eliminated from the mother by way of the milk, passing these contaminants along to their offspring. The fact that male dolphins do not lactate contributes to higher contaminant levels in adult males than in adult females.

Even higher levels of three contaminants (a DDT metabolite, chlordane metabolites and PCBs) were found to be associated with poor health in dolphins. In dolphin calves that died, levels of the same three contaminants were up to 10 times as high as those among the calves that survived.

In other marine mammals high levels of organochlorine contaminants have been linked to reduced immune function, and increased cancer rates. Tumors in beluga whales have been found at 20% in certain populations contaminated with chemicals as a result of living in the Gulf of St. Lawrence. This level of cancer is considered as significantly higher than in non-contaminated populations of marine mammals.

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( 4 ) Pesticides, Wildlife and Human Health

Certain pesticides can act as endocrine disruptors in wildlife and laboratory animals. They may act in a similar way in people. Research needs to address what effects pesticides can have during the 266 day gestation period for the human being. During this time bounds are being placed on the progeny's potential and quality of life. The association between effects in children and chemical pesticides may be indirect so that the agents are not detected in the child's body but only in the body of the mother.

For example: wild caught fish eaten by those living in the Great Lakes area have been associated with problems in children. In the 1970s there was widespread concern over thyroid problems in Great Lakes fish. Infants born of women who ate two to three meals a month of Lake Michigan fish prior to their pregnancies were found to have delays in neuromuscular and neurological development. They showed short-term memory problems and reduced academic skills as they matured.

DDE, the breakdown product of DDT has been associated with reduced reproductive capacities in alligator populations in Lake Apopka, Florida. In the laboratory, female mice fed DDE during gestation produced male offspring that looked much more like females and DDE was found to have anti-androgen (male hormone) activity. The fungicide vinclosalin, also found to have anti-androgen properties, resulted in abnormal males when fed to females during gestation.

A condition in humans called hypospadias, an abnormal opening of the penis, is a "visible external marker of prenatal exposure" to anti-androgen type chemicals. Hypospadias in the US has doubled between 1970 and 1990. See "Toxic Legacies" and Lawn and Garden Pesticide Clusters for further pesticide human health effects.

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( 5 ) Veterinary Pesticides' Effects on Wildlife

Veterinarians are accustomed to focusing on the health of domestic animals primarily and human beings secondarily. The effects of veterinary products on wildlife and ecosystem services are not generally weighed when a therapeutic agent is chosen.

However, such products can reach the environment in an active form by various means including through the feces of large animal patients. Sprays, dips and shampoos used on small as well as large animal patients can contaminate terrestrial and aquatic environments.

Activity of ivermectin-containing pesticides and anthelmintics (used to "deworm" animals) passed in animal feces can reduce the numbers of insects associated with waste matter in fields. These insects perform important ecological functions when they break down organic waste matter, provide food for other wildlife, and pollinate plants.

For example, when ivermectin is present, dung degradation may be impaired for 100 days. In other cases, domestic fowl have died after picking out dichlorvos-containing pellets in horse feces.

Pyrethrin (natural) and pyrethroid (synthetic) insecticides have been replacing the organophosphates/carbamates as animal/premise insect control agents. "Horse stables often have mist sprayers that emit permethrin at set intervals. Dairy barns and swine confinement operations often control fly populations with these agents" (Dr. Blodgett).

In general, the more biodegradable pyrethrins and the more persistent pyrethroids have low mammalian and avian acute toxicity (an exception is permethrin - highly toxic for cats). However, both natural and synthetic forms are considered toxic for aquatic organisms. Snakes, amphibians and bees are also extremely vulnerable to pyrethrins and pyrethroids. Hazards to aquatic life forms occur when there is contamination of surface water with runoff of pyrethrin-type chemicals from spraying or disposal.

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( 6 ) Insecticides' New Modes of Action

Summary: Newly-developed insecticides can be referred to as "selective" if they are not as highly toxic for most mammals and most birds as they are for insects and other wildlife. Four classes of insecticides act on sites in the nervous system that may be common to many animals.

Avermectins and fiproles act at sites known as chloride channels located along the body of the nerve cell. Neonicotinoids and spinosads act on the acetyl choline sites found at the gap (synapse) between nerve cells. A single example is provided along with an RCC toxicity update for each insecticide.

More research is needed to better predict effects of these chemicals in the field including multiple exposures and long term actions on non-target invertebrate and sensitive vertebrate populations (including humans).

Avermectins are derived from natural products made by soil microorganisms. Ivermectin is an example.

RCC Toxicity Update: In general, members of this class are toxic for terrestrial insects, aquatic invertebrates and fish. Environmental persistence and adverse effects on beneficial insects are a problem for ivermectin discussed under topic #5, Veterinary Pesticides' Effects on Wildlife.

Fiproles are a new class of synthetic compounds. Fipronil is an example.

RCC Toxicity Update: Fipronil shows low acute avian toxicity except for certain seed-eating birds such as the Bobwhite quail and the pheasant, which are extremely sensitive to this chemical. Rabbits are also very sensitive to it. Fipronil is highly toxic to aquatic invertebrates, crustaceans, and honeybees. It is also highly toxic to fish and oysters.

Neonicotinoids are synthetic analogs of nicotine. Imidacloprid, a chloronicotinyl, is an example.

RCC Toxicity Update: An imidacloprid-containing product has been associated with "mad bee" disease in France. Beekeepers there report it has killed millions of bees and destroyed the insects' sense of direction. Imidacloprid can also travel throughout the plant and accumulate in the nectar and the pollen.

Imidacloprid could be a problem for honeybees when sprayed into a flowering crop or used as seed treatment. Imidacloprid is highly toxic to house sparrows. In an adverse incident report to the EPA a number of songbirds were found dead after consuming grubs that had come to the surface of a lawn previously treated with imidacloprid.

Spinosads are natural products produced by microorganisms. Spinosad is an example.

RCC Toxicity Update: Spinosad is highly toxic to honeybees and very highly toxic to the Eastern Oyster.

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( 7 ) Effects on Non-Target Insects of Pesticides Used for Gypsy Moth Control

The gypsy moth is an alien insect species that has threatened forests from Massachusetts to the southern states and other parts of the country. Broad-spectrum chemicals used against the pest have contributed to the disappearances of rare species of native moths and butterflies in states along the infestation's path.

Three chemical pesticides, diflubenzuron, terbuphenozide and Bacillus thuringiensis currently used for gypsy moth control have individual ecological effects.

The chemical diflubenzuron, a broad-spectrum inhibitor of chitin formation is extremely persistent on land and in water where it is especially toxic to invertebrate life forms. The total abundance of arthropods, butterflies and moths on foliage in a West Virginia study site remained significantly reduced for over two years after treatment with a diflubenzuron-containing product.

Field testing of the chemical terbuphenozide raised the issue of whether at the level of use needed to control the gypsy moth there would be unacceptable losses of non-target insects. More work is needed to answer this question.

The least persistent and the least toxic to non-target insect life forms is the biological agent, Bacillus thuringiensis (B.t.).

Although persistent chemicals present the most obvious hazard to non-gypsy moth insects, even easily degraded agents such as B.t. if used repeatedly, could be expected to result in loss of sensitive non-targets. Continued widespread use of these chemicals could contribute to further elimination of butterflies, moths and other insects while failing to accomplish the elimination of the gypsy moth.

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( 8 ) Reducing Chemical Pesticides in Agriculture

Ohio State University Professor Dr. Clive Edwards is a researcher of ecological farming methods. Frustrated by the lack of ways to communicate practices through the usual channels, he started Innovative Farmers of Ohio, a group meeting over coffee on regular Saturday mornings to facilitate the exchange of information between organic and conventional farmers.

The group learned about a local farmer who had used organic methods for 20 years and was outproducing neighboring conventional farmers, as well as the enhanced health of plants grown in soil from the organic field compared to those grown in soil from the conventional field.

RCC Update: From Pennsylvania, Maryland's Eastern Shore, Florida, Arizona, Washington, and Indonesia, reports indicate that by reducing chemical pesticides or using organic methods farmers can meet or surpass conventional crop output and/or provide more favorable habitats for birds, aquatic organisms and other wildlife including bacteria.

"The Rodale Farming Systems Trial, started in 1981, found that after a transition period of four years crops grown under organic systems yield as well as and sometimes better than crops grown under the conventional systems."

"Soils managed organically show higher levels of microbial activity and greater diversity of microorganisms. Moreover, organic systems can out-produce the conventional system in years of less-than-optimal growing conditions such as drought."

~ The Rodale Institute Farming Systems Trial: The First 15 Years, 1999

On Maryland's Eastern Shore, farmers were encouraged to reduce the chemical pesticides and fertilizers on their fields through using Integrated Pest Management (IPM). Fish counts and aquatic macroinvertebrates increased significantly in the German Branch, a tributary of the Chesapeake Bay when IPM was adopted by farmers in the watershed. Farmers using IPM also saved money.

~ Frances Breeding, Local Government Pollution Prevention Toolkit, CBP/TRS 202/98, EPA 903-K-98-001

Preliminary data from Florida found that bird densities and the number of bird species associated with organic fields were higher than those associated with conventional fields.

~ Jones, G.A., et al, "An assessment of bird faunas utilizing conventional and organic farmlands of north-central Florida," 2001

Tubac Farms of Arizona economically benefited from implementing wildland habitats near agricultural areas, protected from chemical sprays, in which pollinators could roost, nest and feed in the off-season.

~ Dr. Gary Nabhan, 1998

Organic apple growing in Washington state resulted in healthier soil, better environmental quality, and greater energy efficiency than did growing apples with conventional methods.

~ Nature, April 19, 2001

In Indonesia where most of the pesticide was applied to rice, Dr. I.N. Oka was able to reduce pesticide use by 65% and increase rice yields by 12%.

~ Pimentel, D., "Environmental effects of pesticides on public health, birds and other organisms," 2001

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January 2, 2002