Introduction

On September 25 and 26, 1998, Rachel Carson Council, Inc., in conjunction with George Mason University's
Department of Biology, held a conference on Wildlife, Pesticides and People. Twenty-eight outstanding scientists
from academia, government and environmental organizations made presentations to over 160 attendees from 23
states and 2 foreign countries. The conference was dedicated to Lee Rogers Esq., RCC Board Member and
devoted environmental lawyer, tragically killed March 10, 1998.

The body of information compiled in just two days is sufficiently troubling so as to shake to their very core any
notions that wildlife can be safe from pesticide toxicity if use of these chemicals continues at the present rate.

Most speakers advocated Integrated Pest Management (IPM) as a way of dealing with unwanted species while
reducing chemical use.

Topics ranged from mode of action and environmental fate of chemical pesticides to the hazards they pose for
wildlife such as: invertebrates, fish, birds, mammals, fungi and plants. Most naturally occurring non-target
vegetation including trees and wild flowers have been given virtually no protection from herbicides by pesticide
regulators. Beneficial insects (except for honeybees) and beneficial fungi are not considered when pesticide
toxicity is evaluated by regulators. Although avians are included in pre-registration toxicity tests they are still
threatened. An estimated 67 million birds are killed yearly by pesticides in the U.S. Chemicals too toxic for
use in our own country, but freely available abroad threaten migratory birds journeying thousands of miles from
the Arctic to the Southern Hemisphere. Tiny, obscure but essential aquatic invertebrates are highly vulnerable to
commonly-occurring low levels of pesticides in our streams, lakes and rivers. Even marine mammals with few
natural enemies are at risk from the persistent pesticides that gradually accumulate in their tissues. Indirect effects
of pesticides predicted by Rachel Carson are beginning to receive documentation. Herbicides intended for plants
can indirectly affect insects. Insecticides, by killing off pollinating insects, can lead to reductions in plants. Both
herbicides and insecticides have indirectly reduced bird populations.

Summaries of Conference Presentations, Part I

Note: Significant Conference Findings Part II will include: "Regulatory Aspects of Pesticides
and Wildlife" (Pesticide Regulation and the EPA, Economic Analysis of Pesticides by the EPA,
The Endangered Species Act and The Migratory Bird Treaty Act); "Pesticides and Gypsy Moth
Control;" "Pesticides and Amphibians;" "Pesticides and Marine Mammals;" "Monocrotophos
and Swainson's Hawks;" "Veterinary Pesticides and Wildlife;" "Pesticides, Wildlife and
Human Health;" and "More Wildlife Working Wonders."

Summary At a Glance

1) Nearly All Surface Water is Contaminated with Chemical Pesticides

2) Chemical Pesticides Promote Pests by Killing Beneficial Insects

3) Direct and Indirect Effects of Chemical Pesticides

4) Wildlife Losses Directly Related to Pesticides Are Estimated to Cost Billions of Dollars

5) Effects of Pesticides on: Aquatic Invertebrates, Plants, Fish, Fungi and Birds

5a) The Value of Current Methods for Predicting Pesticide Toxicity to Aquatic
Invertebrates
5b) Super-Potent Herbicides Harm Distant Trees. No Methods Exist to Detect
Their Presence
5c) Early Life Stages of Game Fish at Risk from Herbicides and Insecticides
5d) Effects on Beneficial Mycorrhizal Fungi Are Not Factored Into EPA's
Environmental Evaluation of Pesticides
5e) Pesticides and Birds Parts I and II

6) Endocrine Disruptors

7) Notes on Wildlife at Work

1) Nearly All Surface Water is Contaminated with Chemical Pesticides

Robert Gilliom of the U.S. Geological Survey reported that in nearly every sample of stream water from a
developed watershed, researchers found one or more pesticide contaminants. Based on toxicity data for individual
chemicals, pesticide levels during certain times of the year have been found sufficiently high to threaten
water-dwelling organisms. Moreover, as reported by Dr. Keith Cooper, another conference speaker, a pesticide
mixture can pose a greater hazard than the aggregate toxicity of its constituents would indicate, due to interaction
among its components (synergism). Urban streams were found to have higher organophosphate insecticide levels
(the organophosphates diazinon and chlorpyrifos were found most often) and agricultural streams to have higher
herbicide levels (with atrazine as the leading chemical detected). In each case levels of breakdown products could
exceed levels of the parent compounds by 50 to 100 times. (Some of these breakdown products are more toxic
than the parent chemicals!) For 11 streams, the concentration of dissolved pesticides in the water was the most
reliable predictor of endocrine disruption in the resident carp.

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2) Chemical Pesticides Promote Pests by Killing Beneficial Insects

Dr. William Quarles of the Bio-lntegral Resource Center discussed the effects that chemical insecticides can
have on natural enemies of insect pests, the so-called beneficial insects. Regrettably, beneficial insects appear to be
more easily poisoned by insecticides than are the targeted pests. As explained by Dr. Quarles this enhanced
sensitivity to the toxic effects of chemicals on the part of beneficials has contributed to the higher levels of
pesticide-resistant insect pests. Over 500 instances of pesticide-resistant pest insects have been found while only
30 cases of beneficial insect resistance to pesticides have been documented. An early study found that heavy
applications of DDT in citrus trees resulted in enhanced growth of scale, an insect pest. Removal of the beneficial
insects by hand from citrus tree limbs in a parallel experiment resulted in growth of the scale pest to a level
approximating the DDT-treated tree limbs. When, in both cases the beneficial insects which had effectively
controlled the scale pest infestations were eliminated, the pest was able to thrive. Pest problems from spider mites
and other invertebrates have been linked to the use of DDT and the broad spectrum insecticides which followed
after 1972. EPA does not require the testing of insecticides for their effects on beneficial insects, which act as
natural pest controls and are vital members of the ecosystem. More attention needs to be paid to these important
organisms.

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3) Direct and Indirect Effects of Chemical Pesticides

Here is a catalogue of effects that pesticides can exert, followed by examples taken from Silent Spring as well as
from the Conference presentations of Drs. Ewald and Nabhan describing pesticides' indirect effects on wildlife.

Overview of pesticides' effects on wildlife

Like a handful of stones hitting the water from a single toss, release of a pesticide formulation into the
environment produces ripples of change. The effects can be described as pesticidal and as "chemicidal" (the latter
are toxic effects related to the chemical action of the pesticide). These effects can be due to actions by the active
ingredients, breakdown products, contaminants and/or inert ingredients. The effects can be both direct and
indirect.

Direct effects may be immediate and fatal or non-fatal. They can be delayed, as with a tree's reduced fruit yield or
an animal's developmental disorders, immune system dysfunction, liver or kidney failure or cancer. Indirect effects
exerted over time are by their very nature, delayed actions.

Direct Pesticidal Effects

Chemical pesticides can act directly in their intended way on organisms related to the target pest. Examples of this
are: herbicides poisoning trees and underwater grasses; fungicides poisoning beneficial intracellular mycorrhizal
fungi which produce glomalin.

Direct "Chemicidal" Effects Related to the Primary Mode of Action

Chemical pesticides can act directly in a "chemicidal" way associated with their pesticidal mode of action on
organisms not structurally related to the targeted pests. Examples of this are: organophosphate insecticides
poisoning the nervous systems of birds, aquatic invertebrates, fish and human beings or anticoagulant
(warfarin-type) rodenticides preventing blood clotting in birds or mammals.

Direct "Chemicidal" Effects Unrelated to the Primary Mode of Action

Pesticides behaving as toxic chemicals can have "chemicidal" effects bearing little relationship to the pesticidal
mode of action. Examples include the herbicide 2,4-D acting as a nervous system poison, the herbicide, paraquat,
acting as a respiratory system poison and carcinogenic pesticides such as the fungicides benomyl and
chlorothalonil.

Indirect Pesticide Effects: Examples from Silent Spring, Dr. Julie Ewald and Dr. Gary Nabhan

Indirect actions of pesticides were reported by Rachel Carson in Silent Spring. The most dramatic case from
Clear Lake, California involved the Western grebe and was researched by Dr. Robert Rudd. DDD (a relative of
DDT) was repeatedly sprayed over the lake to kill gnats. After years of bioaccumulation beginning with the
plankton, which had absorbed the poison from the water, through the progressively larger fish species, DDD
reached life threatening levels in the tissues of the fish-eating grebes, described by Rachel Carson as birds of
"spectacular appearance and beguiling habits." The concentration of DDD in the grebes' bodies reached over
80,000 times that of the water. The birds' population was reduced from 1,000 nesting pairs prior to the insecticide
applications to just 30 (most of which did not successfully reproduce) 10 years later. Chlorinated hydrocarbons
such as DDT are still contaminating our environment due to previous as well as present-day usage. They can be
carried on the wind, in the ocean currents or in the tissues of migrating animals to every part of the planet.

In India thousands of tons of DDT were used to control malarial mosquitoes between 1995 and 1996. A recent
report shows that large numbers of vultures there are dying and have high levels of DDT in their carcasses.
Vultures are at the same level of the food chain as humans and serve as sentinels warning of greater pesticide
hazards through indirect effects unless there is a change in the Indian government's pesticide policy.

Partridge Populations Plummet When Pesticides Eliminate Insects

Dr. Julie Ewald from England reported on indirect effects of herbicides and insecticides on birds. She explained
a different type of indirect effect by pesticides that, unlike DDT, do not bioaccumulate. However, these chemicals
were applied regularly over a long time span. Her presentation showed that it is not necessary for pesticides to
bioaccumulate in the food chain (as with DDD and DDT) in order to produce indirect effects if such chemicals are
applied with sufficient frequency. A thirty year study in Sussex found that continuous agricultural applications of
even short-lived chemicals created conditions capable of reducing partridge populations. Coveys of grey partridge
had lived at the field edges in Sussex for hundreds of years before wide-spread use of herbicides eliminated plants
essential for insect cover and food. Broad spectrum insecticides further reduced insect populations. The lack of
available insects during the birds' first two weeks of life turns out to be the chief reason for diminished numbers of
the grey partridge. Young partridge must consume insects in order to thrive. The study's conclusions were further
supported by the finding that planting field perimeters in native wild flowers to foster insect populations seems to
have the potential for reversing the decline of the grey partridge in Sussex.

Loss of Pollinators by Insecticides Results in Declines of Rare Desert Plants

Dr. Gary Nabhan from the Sonoran Desert Museum in Arizona described the indirect effects of insecticides on
plants through reduction of essential pollinators. In his own words, "Rachel Carson not only worried that
pesticides would create 'silent springs' where no bees droned among the blossoms [but she also recognized that
where] there was no pollination...there would be no fruit." He further stated, "Lethal and other effects such as
behavior changes, have been associated with bee exposure to currently-used pesticides. In 1995 the USDA
declared that we are facing the worst pollination crisis in American history. Insecticide and herbicide
spraying causing chemical habitat fragmentation, could impact the over 5,000 species of native wild pollinators
nesting in wild lands adjacent to the croplands." Certain Arizona farms have used conservation areas to help
rehabilitate wildlife populations damaged by pesticides.

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4) Economic Impacts of Wildlife Loss Due to Pesticides

Dr. David Pimentel of Cornell University, the Conference Keynote Speaker, in his manuscript "Economic and
Environmental Costs of Pesticide Use," provided estimates of the cost in economic terms of pesticide use in the
United States:

The estimated pollination losses to food production from pesticides' effects on honey
bees and wild bees is $200 million per year. (p.131)
Destruction by pesticides of the natural enemies of pests can cost an estimated
$520 million per year in the U.S. (p.128)
A conservative estimate of fish (6-14 million) killed per year by pesticides ranges
from $24 to $56 million. "...the actual loss is probably several times the $24 to $56
million estimate when all the indirect impacts are taken into account." (p.137)
The total number of wild birds killed by pesticides is estimated at 67 million. The
value of this bird loss to pesticides is $2.1 billion annually. (p.139)
"Although...invertebrates and microorganisms are essential to the vital structure and
function of all ecosystems, it is impossible to place a dollar value on the damage
caused by pesticides to this large group of organisms." (p.140)

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5) Effects of Pesticides on: Aquatic Invertebrates, Plants, Fish, Fungi and Birds

5a) The Value of Current Methods for Predicting Pesticide Toxicity to Aquatic Invertebrates

Dr. Keith Cooper of Rutgers University described pesticides' effects on aquatic invertebrate organisms, like the
tiny water flea, existing near the bottom of food chains. Although these insects are among the most vulnerable
species to pesticides' effects, their loss within a stream or lake is usually not readily apparent until the more visible
fish species decline or a recreational feature is disturbed. By then it may be too late to remedy the situation.
Frequently, aquatic invertebrates exist in contact with low levels of combinations of chemicals. Knowing the
toxicities of chemicals considered singly and added together might not be sufficient to predict the risk that their
concurrent presence poses to aquatic invertebrates. Researchers have found that toxic effects of low-level
combinations of certain chemical pesticides can be greater than the sum of the effects of the individual
components. When the herbicide atrazine is combined with certain organophosphates, the resulting lethality to
aquatic invertebrates is higher than could be predicted from the toxicities of the individual chemicals because of
synergistic effects among the components. This is not only worrisome for the extremely vulnerable aquatic
invertebrates but for all organisms in an aquatic environment and those who depend on them.

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5b) Super-Potent Herbicides Harm Distant Trees. No Methods Exist to Detect Their Presence

Richard Petrie offered some of the most startling revelations of the conference in his presentation and in a
manuscript by Petrie, Schneider and Czerkowicz, "Plants and Pesticides" reprinted in the proceedings book. His
work stresses the importance of plants and their need for protection so that they can continue to provide essential
services.

Rain and fog frequently carry herbicides such as atrazine to the forests, the Chesapeake Bay and our own farms
and gardens. Yet the EPA requires no testing of herbicides' toxic effects on woody plants or underwater grasses.
Only non-target crop-type plants and aquatic algae have been routinely included in the Agency's required test
groups.

New and very powerful sulfonylurea herbicides have been registered without requirements for testing on trees or
without the development of a chemical test for detecting them in the environment. Many of these sulfonylurea
herbicides have half-lives in years, are widely used, and are reported to have damaged woody plants at a fraction
(1/100 to 1/10,000) of the label dose. As described in the "Plants and Pesticides" manuscript: "Following grower
complaints of yield losses in cherry and apricot orchards downwind from wheat fields treated with chlorsulfuron, a
sulfonylurea herbicide, the EPA conducted limited tests on cherry trees and chlorsulfuron. Reduced cherry yields
were observed the year following the application of chlorsulfuron at 1/500 the label rate...a 1/10,000th dilution of
chlorsulfuron sulfonylurea label dosage resulted in the inhibition of seed production in crop plants..." (p.12)

According to Richard Petrie, two important ecosystems, the Great Lakes and the Chesapeake Bay, threatened by
contamination, will not have restoration of their commercial and recreational resources until the plant life is
renewed to previous historic levels (Petrie, et al). A recent report confirmed that the underwater grasses are
seriously deficient in the Chesapeake Bay. From various sources we know that pesticides are continually present
in the Chesapeake Bay. There is clear evidence that critical data is lacking for an accurate picture of pesticides'
effects on plants.

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5c) Early Life Stages of Game Fish at Risk from Herbicides and Insecticides

Eric Paul explained that numbers of the game fish muskellunge in a New York lake decreased following
widespread introduction of an herbicide to control underwater grasses. Research performed at New York State's
Rome Field Station showed that concentrations of the herbicide diquat, produced when the label recommendations
were followed could be toxic to early life-stages of fish. After labeling changes lowered the use levels in New York
State the muskellunge populations showed signs of recovery.

Eric Paul has researched the effect of insecticides used to control mosquitoes on the early life stages of trout. He
found that at non-lethal levels pyrethrins reduced the swimming ability of young fish. The ability was further
diminished when the synergist, piperonyl butoxide, which enhances the action of the pyrethrin, was present as
would be true for a great many final pesticide formulations. Final formulation tests are not required to include fish.
Active ingredient toxicity tests on fish do not reflect hazards of any synergists found in final formulations. The
enhanced toxicity for young fish of formulations with synergists over and above that of the active ingredient alone
needs to be considered when pesticides' impact on wild fish are being estimated. Recommended application rates
may need to be revised in light of this research.

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5d) Effects on Beneficial Mycorrhizal Fungi Are Not Factored into EPA's Environmental Evaluation of
Pesticides

Dr. Sara Wright with the USDA has shown the important role played by arbuscular mycorrhizal fungi. She
discovered that these fungi produce glomalin, a protein that contributes to soil fertility by facilitating the
aggregation of fine soil particles. Glomalin, as it was named by Dr. Wright, has also been called soil superglue.
Pesticides can interfere with glomalin production. Mycorrhizal fungi living within in the root cells of plants can be
harmed by fungicides or indirectly by the herbicides which poison the host plant. Canadian authorities intend to
require the preregistration testing of pesticides for effects on glomalin production. Although our own EPA has not
yet established such a policy, we need to be aware of the potential for pesticides to harm these organisms.

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5e) Pesticides and Birds: Part I

Dr. Pierre Mineau of the Canadian Wildlife Service, Dr. Mike Hooper of Texas Tech University, Dr. Nimish
Vyas of Patuxent Wildlife Research Center, and Dr. Jewell Bennet of the Fish and Wildlife Service,
internationally-known avian toxicologists presented findings on the effects of pesticides on birds. Recognizing our
society's reverence for wild birds and the body of research data on how pesticides affect them, the Conference
devoted a significant amount of time to this subject.

Birds by their very nature are vulnerable to the direct toxicity of organophosphate (OP) and carbamate
insecticides. Dr. Mineau explained that the greatest direct threat to birds comes from these pesticides. His research
shows that with complex mixtures of pesticides used in orchards, the breeding success of birds is inversely
correlated with the levels of organophosphates and carbamates.

An example of the lethal effects of these chemicals is the deaths of an estimated 20,000 Swainson's Hawks in
Argentina resulting from the use of monocrotophos and other organophosphates. Although monocrotophos may
no longer be used in our own country, it can still be manufactured here and sold abroad.

Songbirds, especially, can suffer what Dr. Mineau calls invisible mortality. These small creatures do not die in a
pile but can die where no one will find them, so that confirmation of pesticide involvement in the death is not
possible. Another effect following continuous use of chemical pesticides is degradation of the land to such a
degree that no bird populations can be supported in the surrounding areas, so that no birds die there.

Dr. Mineau noted that for certain pesticide products the harm they cause doesn't depend on how they are used, but
only whether certain birds are in the vicinity when applications take place. With the granular pesticides even one
particle can be fatal to certain birds. In December 1998 we heard that all uses of granular carbofuran in Canada
had been canceled. This is wonderful news, but because birds migrate, even if all the granular organophosphate
products were banned in the U.S. and Canada, they would still represent a significant threat to birds since they are
sold all over the world.

Under the current practice of pesticide registration each country is free to establish conditions of use. Lax
standards in one country could prove fatal to migratory birds which are cherished and protected by high standards
in another. Drs. Hooper, Mineau and Vyas emphasized the need for uniform protection from pesticide poisoning
all along migratory routes in the Americas and beyond. Accumulated knowledge about a pesticide product should
be available through a world-wide data bank and utilized for pesticide registration instead of each country being
treated as a new situation.

Dr. Mineau explained that the concept of tolerating or allotting a certain number of birds to be killed by pesticides
is not acceptable because science does not allow us to set such limits. Dr. Bennet noted that in the U.S. under the
Migratory Bird Treaty Act it is illegal to kill even one migratory bird with a pesticide.

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5e) Pesticides and Birds: Part 2

Dr. Nimish Vyas of the Patuxent Wildlife Research Institute compared our knowledge of pesticides' adverse
effects on birds to a pyramid-shaped iceberg (in which the widest portion remains unseen). The tip of the pyramid
represents mortality events that have been observed, reported and confirmed. The pyramid base represents the
majority of pesticide-related avian mortality which goes undetected. The lack of documentation for most such
fatalities is due to a number of factors. Up to 92% of the bird carcasses may be scavenged and removed from the
site of the pesticide kill within the first 24 hours. Once a bird kill is observed, it must be reported to appropriate
state and federal wildlife authorities so that a systematic carcass search and sample collection can be conducted.
Often a mortality event may go unreported when an observer finds only one or two carcasses. If the event is
reported there is often a time lag between poisoning and collection of carcasses by wildlife professionals. This
invariably reduces the chance of collecting samples suitable for laboratory analysis.

There is great need for public awareness that pesticides may be involved when a dead bird is found. But unless
there is a reliable method carried out by knowledgeable professionals of investigating and compiling such reports
the public could become frustrated and cynical about the value of vigilance.

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6) Endocrine Disruptors

Dr. Theo Colborn of the World Wildlife Fund spoke on disruption of the endocrine system by pesticides. In
1992, 40% of the pesticides tested were designated as endocrine disruptors. Five years later that number had
increased to 60%. Two of the most widely used herbicides (atrazine and 2,4-D) have been classified as endocrine
disruptors by Dr. Colborn's group. There is special concern about the sulfonylurea herbicides since they are from
the same chemical class as drugs which affect thyroid and pancreatic functions in people. In addition, these new
sulfonylurea herbicides are used at much lower concentrations than are other herbicides, and chemical tests are not
available to detect some of the most widely used sulfonylureas such as chlorsulfuron once they have been released
into the environment. Dr. Colborn cited a study showing that herbicides have been associated with birth
abnormalities in both farmers and non-farm residents living in high pesticide use agricultural areas of Minnesota
(Dr. V. Carry, et al, "Pesticide appliers, biocides and birth defects in rural Minnesota," EHP, v 104, #4, April
1996).

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7) Notes on Wildlife at Work

Thoreau called wilderness, "the raw material for civilization." Although a number of natural areas have become
chemically fragmented through loss of biodiversity from pesticide use since Thoreau's time, certainly many areas
still support vital life-sustaining processes. People today are beginning to realize our dependence on the wild
organisms which are capable of producing these services and the responsibility on our shoulders to protect them
from further degradation as well as to help chemically-damaged areas regenerate into healthy ecosystems.

The term "beneficial" as used by environmentalists traditionally refers to those insects acting as natural enemies of
pests. The Conference showed that "beneficial" can also refer to plants, insects, fungi, reptiles, amphibians and
bacteria which by their very existence maintain ecosystems and make the earth livable for people.

Wild plants generate oxygen and food. They regulate the air and water temperatures and help make the earth
suitable for people and other living organisms. Recent reports indicate that trees may absorb twice as much
pollution each year as was earlier believed.

Approximately one third of all human food is dependent on pollinators. Pollination is required for increased crop
yields and increased quality of fruits and vegetables. (pp.130-131 Pimentel)

Dr. Rosen of the Hebrew University in Jerusalem estimates that 90% of the control of pest species achieved in
agricultural and natural ecosystems is due to natural processes. Dr. Pimentel of Cornell University puts the
number at about 50%. Natural enemies of insect pests include pest-control insects, pest-control nematodes,
pest-control fungi and pest-control birds as well as others.

Birds provide a valuable service to growers and to the public through controlling insects. A case in point occurred
in China during the 1950s. Chinese officials grew concerned that flocks of birds were allegedly devouring large
amounts of grain. They declared any sparrow-like perching bird to be a major scourge. "With regimented
enthusiasm" the citizens killed over 800,000 birds. As a consequence there were major outbreaks of insect pests.
Realizing their mistake the leaders changed course and removed small birds from the list of scourges. (Baskin, Y.
The Work of Nature. Island Press. Washington, DC. pp.42-43) It is difficult to know precisely how the killing
of birds by pesticides relates to pest insect populations. However, the estimated bird losses due to pesticides
given by Dr. Pimentel, 67 million per year, far exceeds the 800,000 bird deaths in China that resulted in
greater insect numbers.

It has been estimated that before 1880 resident oysters in the Chesapeake Bay were able to filter all the Bay's water
in 2-3 days. In 1988 the time required for oysters to provide the same service was 325 days or 100-fold longer.
We do not know what effect pesticides may have had on the loss of water filtering service provided by these
bivalves. We have determined that pesticides have been identified as toxic to mollusks.

We know that many vital services from nature are threatened by chemical pesticides, and that biological alternatives
to the use of chemicals for control of unwanted species are underutilized. More attention needs to be given to the
urgent problems resulting from the use of chemical pesticides.
~ May 1999

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