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Title: A stench from its inky surface putrescent with the oxidizing processes to which the shadows of the overreaching trees add stygian blackness and the suggestion of some mythological river of death. With this burden of filth the purifying agencies of the


1
"A stench from its inky surface putrescent with
the oxidizing processes to which the shadows of
the overreaching trees add stygian blackness and
the suggestion of some mythological river of
death. With this burden of filth the purifying
agencies of the stream are prostrated it lodges
against obstruction in the stream and rots,
becoming hatcheries for mosquitoes and malaria.
A thing of beauty is thus transformed into one of
hideous danger."
Texas Department of Health
1925"There are three kinds of lies. Lies,
damned lies, and statistics!"
Mark TwainUnder
carefully controlled laboratory conditions an
organism does what it damn well pleases.
Harvard
Law"What's the use of their having names", the
gnat said, "if they won't answer to them?""No
use to them," said Alice "but it's useful the
people who name them, I suppose. Through the
Looking Glass Lewis Carroll
2
Cyclomorphosis Cyclomorphosis is, as the name
indicates is a cyclic change in body form. This
occurs primarily in female lemnetic species such
as Daphnia pulex and Daphnia rosea. A population
of cyclomorphic species has a homogeneous
normalor rounded head, form in the fall, winter
and early spring. As the water becomes warmer
the populations develops, however, there is a
commonly progressive increase in the longitudinal
axis produced by a general elongation of the head
and the appearance of a helmet.
Characteristically, the helmets become fully
developed by midsummer, when they may be quite
bizzarre. Beginning in late summer or early
autumn, the morphology of the head progressively
reverts so that the normal condition prevails
by late autumn. In the words of Coker (1939),
The changes in form are not simple functions of
external conditions or of any inherent cycle, but
rather of a combination of internal and external
conditions in a way that becomes exceedingly
baffling the more we know about it. Theories
about helmet shapes Under conditions of low
dissolved oxygen Cladocera often produce
hemoglobin to facilitate the transfer of oxygen.
Studies have been done which strongly suggest
that given the choices of red/pink Cladocera and
a normal colored Cladocera, fish choose the
red/pink Cladocera. There would therefore appear
to be a selective disadvantage to becoming
red/pink. One theory suggests that the increased
size of the helmet of Cladocera functions to
increase surface area over which oxygen can be
extracted from the water and therefore changing
helmet dimensions would be a function of reduced
dissolved oxygen. Another theory suggests that
as the water temperature increases the density of
the water decreases and therefore animals such as
Cladocera have to expend more energy to keep from
sinking. Since the food of the cladocerans is
mostly algae and since algae live near the
surface, decreasing the amount of energy
necessary to stay higher in the water column
would be a selective advantage. One way to
counter the tendency to sink would be to increase
the helmet dimensions.
3
D-H are all Daphnia retrocurva
4
Poikilotherm having a body temperature that
varies with the environment, cold blooded as are
amphibians, reptiles, fishes, insects Homiotherm
having a constant body temperature,
warm-blooded as are mammals and birds Q10 law
or VanHofts Law which states that a doubling of
temperature between 10 and 20 ºC increases the
metabolic rate by 2 fold. Inverse metabolic rate
law the smaller the organism the greater the
metabolic rate on a per gram basis. Therefore, it
takes more energy to support 10, 1 gram
organisms than it does 1, 10 gram organism. If a
rhinoceros had the metabolic rate of a mouse
it would have to endure boiling temperature at
its surface in order to dissipate heat generated
as a result of metabolic processes. Physoclist,
physostome, no gas bladder Diurnal Diel Nocturnal

5
At 25 C and well fed a female Ceriodaphnia dubia
will have its first brood (4 to 6 neonates)on day
4 after its release from the brood pouch. On day
5 it will have a second brood (7 to 10 neonates)
and on day 7 it will have its third brood (15 to
20 neonates) All of these offspring will be
female unless something happens to induce the
sexual part of cyclic parthenogenesis.
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7
Very Early Stages of Development Embryo (0 hours
old)
8
Embryo 3 Hours
9
Embryo 5 Hours Old
10
Embryo 8 Hours
11
Embryo 11.5 Hours
12
Embryo 13.5 Hours
13
Embryo 14 Hours
14
Embryo 14.5 Hours
15
Embryo 16.5 Hours
16
Embryo 17.5 Hours
17
Young C. dubia In Last Embryonic Membranes
18
First Antennae of Female Ceriodaphnia dubia
19
First Antennae of Male Ceriodaphnia dubia
20
First Antennae of Male Ceriodaphnia dubia
21
Female With Fertilized Egg In Brood Pouch
22
Female With Fertilized Egg In Brood Pouch
23
Ephippium With Resting Egg
24
Ephippia
25
Sampling Devices Ekman Dredge Ponar
Dredge Surber Sampler Kick Net ½ meter net
macrozooplankton Microzooplankton closing
net Artificial Substrates Diatometer
26
Distributions
27
Mean, Variance, Standard Deviation and Confidence
Limits Data Set 1 Data Set 2 10
5 10 80 10 0
10 1 10 0
10 0 10 0
10 7 10 3 10
4 Total 100 100
n 10 10 Ave 10
10 Variance 0 611 St. Dev
0 24.7 C.I. 10/-0
10/-17.7 Variance ?(xi2) - ?(xi)2/n
Standard Deviation (St. Dev) square root of the
variance Confidence Interval (CI) Mean ? tvalue
(St. Dev.) The t value is chosen based on
sample size and ? or probability level t value
for 95 Confidence Interval and n10 is 2.262
n-1
?n
28
1-?/2 n-1 d.f. If ? 0.05
29
Data Set 3 10 12 14 17 28 2 6 21 10 15
Calculate the mean, variance standard deviation
and 95 Confidence limits for Data Set 3
Mean 13.5 Variance (s2) 55.17 Standard
deviation 7.43 Mean ? 5.3 (13.5 ? 5.3)
If you have an n of more than one you can
calculate a mean and confidence intervals about
the mean
30
Failing to reject the null hypothesis does not
mean that there is not a difference!!!!
Ho There is no difference in the mean number of
benthic organisms above and below the outall. Ha
There is a difference in the mean number of
benthic organisms above and below the outfall.
31
Correlation and Regression The purpose of
correlation analysis is to measure the intensity
of association observed between any pair of
variables and to test whether the association is
greater than can be due to chance alone. Once
established, such an association is likely to
lead to reasoning about causal relationships
between variables. Students of statistics are
told at an early stage not to confuse significant
correlation with causation. Regression deals
primarily with the means of one variable and how
their location is influenced by another variable.
Regression comes close to implying cause and
effect relationships. Thus, where a correlation
coefficient tells us something about a joint
relationship between variables, a regression
coefficient tells us that if we alter the value
of the independent variable then we can expect
the dependent variable to alter by a certain
amount on average. The correlation coefficient
r can range between -1 and 1 and the value of r
tells us something about the degree of
relationship between the two variables. The
coefficient of determination r2 used in
regression analysis (the square of the
correlation coefficient) tells us how much of the
variation in the dependent variable can be
explained by its association with the independent
variable. An r2 of 0.90 indicates that 90 of
the variation in the dependent variable can be
explained by its relationship with the
independent variable. In a sample size of 200,
an r of 0.2 would be significant at the 1 level
of significance, but the would only indicate that
4 of the variation in Y could be explained by
its relationship with the X variable. A verdict
of statistical significance shows merely that
there is a linear relationship with a non-zero
slope.
32
In fact, the condition factor was significantly
correlated with DNA damage (R -0.413, P0.045)
and MT levels (R -0.622, P0.03).
At a probability level of 0.05, any value of P
less than this would be statistically
significantly different.
Significance in these cases means that the slope
is statistically significantly different from 0.
-0.413 17 -0.622 39
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36
Starlings (Sturnus vulgaris) It is the first of
February, and everyone is talking about
starlings. Starlings came to this country on a
passenger liner from Europe. One hundred of them
were deliberately released in Central Park.
According to Edwin Way Teale, their coming was
the result of one mans fancy. That man was
Eugene Schiefflein, a wealthy New York drug
manufacturer. Schieffelin formed a club called
The American Acclimatization Society who had as
their goal the introduction into the US all the
birds mentioned by William Shakespeare. The
birds were released in Central Park in New York
and first nested under the eaves of the Northwest
wing of the Museum of Natural History. The birds
acclimated splendidly, in less than 60 years the
100 or so birds released into Central Park
increased to more than a million and by 1954 had
reached Alaska. The king forbade my tongue to
speak of Mortimer. But I will find him when he is
asleep, and in his ear Ill holler Mortimer!
Nay Ill have a starling shall be taught to speak
nothing but Mortimer, and give it to him to keep
his anger still in motion was the only line in
Henry IV that provoked such a reckless act.
These birds are controlled in England and other
parts of Europe by the normal array of
competitors, predators and diseases with which
the bird evolved. These controls were not
present in the US so the bird spread rapidly, and
out competed many of our native birds. Youll
begin to hear pneumatic cannons on our campus a
little later in the spring as attempts are made
to drive off the starlings and boat tailed
grackle that roost on our campus.
Anne Dillard in her book Pilgrim at Tinker Creek
writes, Starlings are notoriously difficult to
control. The story is told of a man who was
bothered by starlings roosting in a large
sycamore tree near his house. He said he tried
everything to get rid of them and finally took a
shotgun to them killing three. When asked if
that discouraged the birds, he reflected a
minute, leaned forward, and said confidently,
Those three it did.
37
Passer domesticus
Several different versions regarding the
introduction of the English sparrow. The sparrow
entered the US as a gesture of friendship. As the
steamship Europa steamed up the Hudson River the
birds were released as a gesture of friendship
to the U.S. In reality the English sparrow was
introduced numerous times before it finally took
hold. Native to the Old World, the bird was
first introduced into the United States about
1850 to combat cankerworms, and it rapidly became
widespread. Aggressive as well as prolific, it
has largely replaced many native birds in urban
areas.
In 1912 The English Sparrow As a Pest? Farmers
Bulletin 493, by USDA noted they eat more than ½
their own weight in grain or other food a day. It
contained recipe for house sparrows.
38
  • By 1887, some states had already initiated
    efforts to eradicate HOSPs. States such as
    Illinois (1891-1895) and Michigan (1887-1895)
    established bounty programs. According to Keith
    Kridler, since the bounty on "English" Sparrows
    was only a few cents per bird in many states,
    young children killed these birds to earn money
    for "hard candy." The children quickly learned to
    wait for the eggs to hatch and thus quadruple
    their bounty. County clerks often felt sorry for
    these children, and paid out the bounty on any
    species of sparrow. A 3/16/1892 article in an
    Indiana PA paper stated "The different county
    treasurers of Illinois have paid out in round
    figures 8,000 as bounty money under a law
    allowing 2 cents for the head of each sparrow
    killed during December, January and February in
    that State. This shows that about 450,000
    sparrows were killed, but the frisky bird seems
    more numerous than ever."
  • On 09/06/1888, The Cartersville Courant-American
    newspaper noted "The English Sparrow, with its
    grown and growing progeny, is a conspicuous
    nuisance. Can they be no way devised to abate
    him, if not totally, at least partially?"
  • An 1883 article in The Messenger (Indiana, PA,
    06/27/83) said "The little sparrow has been
    declared an outlaw by legislative enactment and
    they can be killed at any time. They were
    imported into this country from Europe some years
    ago as a destroyer of insects, but it has been
    found they are not insectivorous. Besides they
    drive away all our native song birds and give no
    equivalent. Let them all be killed."
  • In 1903, W.L. Dawson wrote "Without question the
    most deplorable event in the history of American
    ornithology was the introduction of the English
    Sparrow." (The Birds of Ohio, 1903)

39
Professor Ettiene Leopold Trouvelot Professor
Trouvelot wanted a hardy caterpillar which would
feed on oak leaves and spin a cocoon of silk. He
thought such a useful creature might be produced
by crossing the American Silk Moth, Bombyx mori,
which feeds on mulberry and produces a large
cocoon, with the Gypsy Moth, Lymantria dispar,
which feeds on oak leaves. He was apparently
culturing the gypsy moths on trees in his
backyard when some of them escaped. Trouvelot
understood the potential magnitude of this
accident and notified local entomologists, but no
action was taken. After the accident, outbreaks
began to occur in Trouvelots neighborhood and in
1890 the State and Federal Government began their
attempts to eradicate the gypsy moth. Trouvelot
apparently lost interest in entomology and became
interested in astronomy. About 10 years after the
accident He became famous for his illustrations
of astronomical details of Venus and was
eventually given a position at Harvard University
in Astronomy. A crater on the moon was named in
honor of Trouvelot and he won the French
Academys Valz prize for his astronomical
research. The gypsy moth is now one of North
Americas most devastating pests. In one of their
record breaking years they defoliated almost 13
million acres in 1993, they devoured a mere 1.8
million acres. This species originally evolved in
Europe and Asia where it has existed for
thousands of years. Each year about 1 million
acres of forest are sprayed aerially with
pesticides in order to suppress outbreaks of
gypsy moth populations.
40
Though some areas are treated by private
companies under contract with private land
owners, most areas are sprayed under joint
programs of the state and USDA Forest Service.
Millions of dollars of tax money have been spent
trying to eradicate and/or control the gypsy
moth. More recently, the Asian gypsy
mothtraveled as stowaways on boats from Russia
to the West Coast in 1991 and from Germany to
North Carolina in 1993. The Asian moths eat more
voraciously than the Europeans and, because the
females can fly, may spread four to five times
faster. This gypsy moth is known to feed on the
foliage of hundreds of species of plants in North
America but its common hosts are oak and aspen.
Gypsy moth hosts are located throughout most of
the conterminous US but the highest
concentrations are in southern Appalachian
Mountains, the Ozark Mountains, and the Northern
Lake States. Every year isolated populations of
are discovered beyond the contiguous range of the
gypsy moth. Most die out but it is inevitable
that the gypsy moth will continue to expand in
the future. New studies suggest that Dimilin,
one of the most effective pesticides against the
gypsy moth, does more damage to the environment
than previously thought. Dimilin, also destroys
insects vital to the health of the forest
ecosystem. Dimilin is the cheapest and most
efficacious way to kill gypsy moths but the
chemical has also become the bad boy of
pesticides because of its non-target effects.
Studies indicate that of all the arthropods in
the tree canopy, the macro-Lepidoptera larvae
which includes the butterflies and big moths
suffer the greatest loss. These arthropods, and
others dont seem to recover for longer than a
year after spraying, play a critical role in the
forest ecosystem as food for bats and birds.
Dimilin is also incredibly toxic to aquatic
invertebrates compared with alternatives.
41
Under the Toxic Substances Control Act (TSCA) the
risk of chemicals to human health and the
environment are supposed to be evaluated before a
chemical is allowed into commerce. Many of the
100,000 chemicals in commerce have never been
evaluated because they were already in commerce
when the TSCA was passed in 1976. Approximately
2,000 new chemicals come into commerce in the US
each year. The ecological risk assessment is
done by calculating the ratio between the
Predicted Environmental Concentration (PEC) and
the Predicted No Effects Concentration (PNEC).
For fish medicines- based on acute data the
ratio of these two parameters is lt1 the
environmental effects are considered low are
non-existent. If the ratio is greater than 1 or
the log Kow is gt3 or the DT50 in water is greater
than 4 days further studies including chronic
toxicity are carried out. the various factors
DT (dissipation time), Kow, organisms tested vary
depending on the environmental compartment into
which the chemical might go (air, water, soil,
etc.)
42
Log Kow for selected environmental
contaminants.. DDT 6.19 (1,548,816 times more
in octanol than in water). DDD 5.5 DDE
5.7 PCBs congeners range from 4.65 to 7.36
(22,908,676) with the higher the chlorination the
greater the log Kow Synthetic musk compounds
used in detergents, shampoos, perfumes Kow
6 Triclosan log Kow 4.76, methyl triclosan log
Kow 5.2 2,3,7,8-TCDD (dioxin) Kow 6.80
contaminate in 2,4,5,T Dibenzofuran Kow 5.17
contaminate in 2,4,5,T Chloroform Kow
1.97 Benzene Kow 2.13
43
The use of dimilin (diflubenzuron) is expected
to cause adverse acute and chronic effects to
both freshwater and estuarine/marine
invertebrates, including endangered species.
Chitin inhibitor. To lessen the environmental
risks posed by diflubenzuron, EPA is requiring
the following risk mitigation measures Row crops
and orchard uses must include a 150 foot buffer
zone for aerial applications and a 25 foot
vegetative buffer strip to decrease runoff in all
cases (buffer strip will also serve as a buffer
zone for spray drift from ground
applications) Aerial applications must include
the most current spray drift language and All
products must CONTAIN a hazards statement warning
about possible adverse effects to aquatic
organisms.
44
White Pine Blister Rust Cronartium
ribicola Introduced into the US from timber
shipments from Europe. It is a heteroecious
(requires two hosts) parasite. The two hosts are
the white pine tree which is commercially
valuable and wild currant and gooseberries of the
Genus Ribes. One spore is found associated with
the white pine tree and this spore must be
transmitted to the intermediate host, the wild
currant or gooseberry before the spores
infectious to the white pine tree, are formed.
The spores that infect the white pine trees may
travel long distances however, the spores that
carry the infection from the wild currants and
gooseberries to the white pine trees seldom
travel more than 1000 feet. The control strategy
for this disease was to eradicate the wild
currant and gooseberry bushes within 1000 feet of
white pine trees. We used 2,4,5-Trichlorophenoxy
acetic acid and 2,4-Dichlorphenoxy acetic acid.

2,3,7,8-Tetrachloro-dibenzo-p-dioxin
Agent Orange has been linked to cancers and
other diseases in several epidemiological
studies. The Agent Orange cancers and diseases
include prostate cancer, respiratory cancers,
(lung, trachea/bronchus, larynx), soft-tissue
sarcoma, non-Hodgkin lymphoma, Hodgkin disease,
chronic lymphocytic leukemia (CLL), and multiple
myeloma.
Unlike PCBs dioxins have no uses they are
contaminants of manufacturing
45
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46
Hydrilla sp Most native aquatic vegetation
enhances aquatic ecosystems. Some of the
benefits that are derived include fish and
waterfowl habitat, sediment stabilization, and
improved water quality with respect to nutrient
removal and water clarity. However, many
introduced species can have negative impacts.
Aquatic ecosystems are often destroyed as a
result of the increased biomass, dense canopy
production, and the loss of diversity due to
aggressive, weedy growth patterns that overwhelm
native vegetation. One such non-native aquatic
plant that causes excessive negative impacts is
hydrilla (Hydrilla verticillata. Hydrilla is
native to Southeast Asia and Australia. It was
first discovered in the U.S. in the 1960s. Two
distinct biotypes one monoecious (both sexes on
the same plant), and dioecious (one sex per
plant) exist in the U.S. Monoecious Hydrilla was
discovered in 1982 in the Potomac River, just
outside Alexandria, VA. It has since been found
in other parts of Virginia, in addition to North
Carolina, Delaware, Maryland, California, and
Washington. Hydrilla is also found in Texas and
in fact is in Lake Ray Roberts, North Lake, Lake
Conroe, among others. Once Hydrilla invades
an aquatic ecosystem, the plant spreads rapidly
either by root crown, and stolon growth or by
drifting fragments or turions. Hydrilla also
produces an underground tuber, another
reproductive strategy for survival. Monoecous
Hydrilla produces viable seed, whereas dioecious
Hydrilla in the U.S. produces only female
flowers. Hydrilla can rapidly produce a dense
canopy , shading out desirable native vegetation
and reducing plant diversity. To improve
Hydrilla management, the U.S. Corps of Engineers
Aquatic Plant Control Research Program supports
studies in four main technology areas.
Biological control, chemical control, ecological
control, and simulation technologies. Biological
control (fungal pathogens, insects), chemical
control (exposure time for herbicides, and use at
the operational level) , ecological control
investigates parameters determining the
distribution, The simulation technology has been
developing growth models for Hydrilla and
specific control techniques such as herbicides,
harvesting, and/or triploid grass carp.
47
Polyploid an individual or species whose
chromosome number is a multiple other than two of
the haploid number of chromosomes. Polyploidy a
condition in which an individual posses one or
more sets of homologous chrmosomes in excess of
the normal diploid sets as, triploidy,
tetraploidy, hexaploidy, octaploidy, and 16, 32,
64 etc. ploidy. Colchicine Heterosis hybrid
vigor, increased size, faster growth rates,
resistance to disease, etc. Homologous
chromosomes a pair of chromosomes which have
identical genes on their alleles
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49
Water Hyacinth (Eichhornai crassipes)
Hyacinth was allegedly first brought from Brazil
as table decorations for the 1884 Cotton States
Exposition in New Orleans. A woman brought one
from the exposition home to Florida and put it in
her backyard fish pond. Within 10 years the
colorful plant had become a public menace.
Unchecked by natural enemies and nourished by
Floridas nutrient rich waters, the water
hyacinth, which can double its population size in
two weeks, rapidly displaced native aquatic
plants and took over. Transported by boat
propellers, river currents, birds, and wind the
plant was soon widely spread. The hyacinth is
very plastic in its habitat. It has a tenacious
ability to multiply. It floats on the surface
and extends its roots 6 to 24 inches into the
water. It can survive under extreme conditions.
If water dries up it extends its roots into the
bottom mud. The dense mats block the surface
exchange of oxygen from the atmosphere to the
water which can lead to anaerobic conditions.
The mass can become so dense as to cause floods
during spring runoff.
50
  • Control of hyacinth.
  • Efforts to control the water hyacinth began in
    1898 with the help of the Army Corps of
    Engineers which was authorized by Congress to
    remove hyacinth from navigable waters of Florida,
    Mississippi, Alabama, Louisiana, and Texas. The
    methods they used were
  • Mechanical chopper
  • Within two years the COE found a chemical sodium
    arsenite, which did the job more efficiently.
    Even though sodium arsenite was recognized as a
    deadly chemical, the COE used the chemical for
    hyacinth control for about 35 years between 1902
    and 1937.
  • In 1937 a new crusher boat was introduced that
    had a large conveyor belt. Plants were harvested
    and transported to shore to dry. It did not
    operate well in shallow water and the cleared
    areas were quickly re-inhabited by plants that
    were not removed.
  • In the mid 1940s the hebicide 2,4-D became
    available and has been used extensively.
  • Amazingly, the integration of mechanical removal
    along with herbicide application is being used to
    control infestations.

51
More recently scientists have sought to join
forces with nature to control hyacinth. There
are several predators (herbivores) which in large
enough numbers could eliminate the constant
attention and manpower necessary in mechanical
and chemical control. A species of weevil from
Argentina is being used. This species feeds
exclusively on hyacinths so there is no danger
it will attack beneficial plants. There is a
small snail from Puerto Rico that has been
examined but it feeds on plants other than
hyacinth. Other mites, fish, turtles have been
tested as biological control mechanisms.
Studies at the University of Florida in
Gainsville analyzed the chemical content and
nutritional value of hyacinth as cattle feed.
Found that it cannot occupy more than 25
hyacinth or the cattles weight will go down.
Another problem is that cattle apparently dont
like its taste. More than a century of control
efforts with expenditures of millions of dollars
with minimal success.
52
Waif something found without an owner and
especially by chance
53
Fire Ants Seven species of fire ants (Solenopsis)
are distributed throughout the warm temperate
regions of the Americas. Shortly after World War
I a dark form S. saevissima from Argentina became
established in Mobile, Alabama and slowly spread
to surrounding regions. In the 1930s a smaller
reddish form of Solenopsis appeared in the same
region, apparently representing a second major
introduction. The latter form aggressively made
its way beyond the States borders swamping out
by interbreeding and internecine warfare (violent
death marked by slaughter) the established black
phase. At present the North American populations
are chiefly the red phase, tending to replace
native forms as well as the dark phase. In 1957
the U.S. Department of Agriculture requested
congressional approval for control of the fire
ant. The request was granted and a 2.4 million
dollar allocation was approved with the
stipulation that matching funds be made
available. Most states and many individuals did
respond with matching funds, but very often
control programs went ahead without them. A
massive operation was set up with great speed.
The first spraying using 2 pounds of dieldrin
(chlorinated hydrocarbon, on the POPs list, log
Kow 5.17) or heptachlor (chlorinated hydrocarbon
on the POPs list, Log Kow 5.5) per acre began in
November 1957. Over two and one-half million
acres were aerially treated. Not until the
operation was well underway were wildlife and
health authorities notified. Immediate opposition
to the program resulted-opposition was to grow to
a national controversy. Fish, wildlife,
livestock, and poultry suffered losses, the
destruction of wildlife bordered on the
catastrophic. The insect was not considered more
than a nuisance in any of the southern states it
did not destroy crops, wildlife, and livestock.
54
However, chemicals did eliminate vertebrates from
some areas, it did cause residue problems, it did
contribute to insect outbreaks themselves
requiring control. It did not eradicate the fire
ant the ants re-infested most of the treated
areas. The Plant Pest Control Division of the
Dept. of Agriculture had clearly made a massive
mistake the operation was a failure from its
inception. Between 1962-1978 Mirex was used as a
bait to kill fire ant colonies. Mirex was banned
for use (it is on the POPs list, Log Kow 5.28) by
EPA because it was shown to pose serious human
health hazards. Mirex is converted to Kepone (Log
Kow 4.07) by photolysis. The imported fire ant
now infests more than 230 million acres in
Alabama, Florida, Georgia, Louisiana,
Mississippi, North and South Carolina, and Texas.
Somewhere in the neighborhood of 175 to 200
million federal dollars have been spent trying to
first to eradicate and now control this pest.
Economic-When soybean combines cut through fire
ant mounds their blades and rollers must be
replaced two or three times a season compared to
once every four years under good conditions.
Farmers have been known to leave valuable crops
in the field to protect their machinery. Citrus
growers in Florida are spending about
110/acre/year to replant some varieties of young
trees that die because they are girdled by fire
ants. Studies by two U of Florida researchers
found that infestations of fire ants actually
increased on insecticide treated plots that
originally had low infestation levels. The amount
of increase on treated plots was somewhere
between 200 and 3000 percent. Because the
imported fire ants colonize better than other
ants you inadvertently select for imported ants
when you eradicate all other ants.
55
Home control can be achieved by using boiling
water on the mounds. Tends to kill the grass
around the mounds. Farmland and Rangeland
controls using synthetic growth hormones like
Pro-Drone that prevents the larvae from
developing into normal workers. Large areas of
Texas have been treated. Some researchers believe
that the Pro-Drone will act like the broad
spectrum pesticides and actually increase the
infestation. Researchers are looking for
predators, fungi, or bacteria in native Brazil
for control mechanisms. In Brazil the fire ant is
not a significant problem. Clearly something in
Brazil is controlling the density of fire ants.
Our native fire ant species is a minor nuisance
at home, but a major pest in India where it was
inadvertently introduced. Former Texas
Agriculture Commissioner Regan Brown told a
national fire ant symposium that, This is not an
infestation it is an invasion. This is the same
guy who, on national TV, stuck his fist into a
fire ant mound and then spent the rest of the
interview trying to get the dam things off of
him.
56
Zebra Mussel (Dreissena polymorpha) The Zebra
mussel is a fingernail sized mussel native to the
Caspian Sea. First discovered in the US in 1986
in the St. Clair River near Detroit where larvae
were probably discharged along with freshwater
ballast, these incredibly prolific bivalves have
spread explosively throughout the Great Lakes.
Female Zebra mussels can produce up to a million
eggs per year, which develop into microscopic,
free swimming larvae that form shells and attach
to any surface. Unchecked by natural
predatorsin Europe they are eaten by fish and
diving ducks-the mussel can reach population
densities of gt90,000 per square meter. They clog
pipes and shut down water intake systems (steam
electric plants). They pile up on boats, buoys,
and piers crowding out native species. One
utility estimated it will cost 50 to 100 million
dollars to scrape the mussels from cooling pipes
at their power plants. One beneficial effect
is that the mussels have made Lake Erie
noticeably clearer by filtering water through its
feeding apparatus. The exotic Zebra mussel
probably invaded the Mississippi Basin via canals
linking Lake Michigan to the Illinois River, a
major tributary of the Mississippi. First
reports in the basin were from these canals in
1989 and 1990, so it is not surprising that the
densest and most extensive populations are from
the Illinois River (up to 94,504/m2). The
percentage of native mussels infested with
Zebras increase from 3 up river to 99.5 down
river. Judging from researchers in the area the
Zebra mussels threatens the 23 native species of
mussels. Freshly dead native mussels (with meats
inside) were found so heavily infested with
zebras that their shells could not be forced
closed. Others were held shut by byssal threads
(mechanism by which Zebra mussels attach
themselves to the substrate). Mussels that can
neither close nor open will not survive.
Researchers recommend that action be taken now to
cryogenically preserve gametes or fertilized eggs
of native riverine mussels or to move adults to
hatcheries where they can be maintained and
perhaps propogated. Native mussels might be
stocked in the future if the Zebra mussel
populations every crash.
57
Data 26,000 acre lake (surface acres) Weed in
the lake is Hydrilla veticillata, native of the
old World tropics i.e., Africa Weed is spreading
at the rate of 15 per year. Home owners around
the lake have collected money and tried Mowing
machines, and Eli Lily Co. spread chemicals,
nothing has stopped the spread. Lake is also
used as a drinking water source for a major
metropolitan area (provides about 40 of its
drinking water). Home owners and marina owners
claim they are losing 10s of millions of dollars
in lost revenue and property values. Weed has
choked off recreational area use of shore lines
and coves. The weed often traps swimmers and two
have drown. Home owners have the opportunity to
buy 240,000 grass carp (white amur,
Ctenopharyngodon idellas) for 250,000 they have
raised from private sources (1.04 per fish).
The grass carp has been imported from the Soviet
Union, and is being tried as a water hyacinth
control as well. What Lake is it? You work
for the Texas Fish and Game Commission and you
have to decide whether or not to let them bring
in these fish. A law exists that prohibits the
import of piranha and walking catfish in addition
to the grass carp. The Legislature would have to
be convinced to do this. Bass fisherman say that
importing the fish will make the best large mouth
bass lake in the State the worst.
58
  • Characteristics of the grass carp
  • Known to eat vegetation other than Hydrilla.
  • Requires running water to breed successfully.
  • Resembles a big silver colored goldfish and can
    weigh up to 100 pounds.
  • Texas legislature was convinced to approve a 5
    year study beginning in 1981
  • By 1984 all significant vegetation in Lake was
    gone
  • Grass carp are eating leaves off of willow trees,
    and 2-3 inches of grass up from the shoreline.
  • Largemouth bass are harder to catch (lack of
    cover and declining population?). Bass catch is
    down 25, crappie catch is down 60 grass carp
    catch is way up, corn and dog food used as bait,
    fish is a vegetarian (20 to 25 lbs each), claims
    are made they are good to eat. Water fowl
    populations are way down.
  • Grass carp now found in the Trinity and San
    Jacinto Rivers. Where they came from no one is
    sure.
  • Some Parks and Wildlife biologists believe
  • a. the carp will die out in 5 to 10 years
    because they need running water to spawn.
  • b. Hydrilla which still has roots in the lake
    bottom will return
  • c. Pressure now on to use grass carp in Houston
    Lake, Lake Jacsonville, Lake Livingston, Lake
    Worth, and Lake Plaestine.
  • Triploid carp are available at 5.00 per fish. A
    triploid grass carp is now in effect on this
    lake. If a grass carp is caught it must
    immediately be returned to the water.

59
There have been repeated instances over time
where organisms, for a variety of reasons, have
been imported into the U.S. In some cases the
organisms were brought in on a whim (starlings),
in the name of science (gypsy moth), to attack a
specific problem (English sparrow) or as an
accident. The current epidemic of the spread of
bird flu is an example of how quickly things can
spread due to both natural conditions as well as
our ability to travel almost anywhere in the
world. The zebra mussel entered the US in the
ballast of a ship as have many other hitchhikers,
the reverse movement from the US to other
countries is also possible. A law is before
Congress (2008) to require ballast to be dumped
and filled with saline water before ships can
enter territorial waters. One underlying problem
associated with almost all of these introductions
is that at home they are generally well behaved
(their populations are controlled by many forces
they have evolved with) when introduced into a
foreign area without the control mechanisms the
populations almost always explode. Sometimes
we introduce new species in an attempt to solve
problems created by previous introductions but
end up making the situation worse. In Hawaii and
several Caribbean Islands for instance, mongoose
were imported to help control rats that had
escaped from ships and were destroying indigenous
birds. Since the mongoose were diurnal, and the
rats were nocturnal they tended to ignore one
another. Instead the mongoose also killed native
birds and further threatened endangered species.
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