Bioeradication

Richard Gardnerrtgardner3@yahoo.com

June 19, 2013

This is an extension of a pair of presentations I gave at the NENHC 2013 in April of this year on

the control of non-native invasive species. The first paper was on Bioeradication, with examples. The second was a presentation of Ailanthus altissima chemical control and bioeradication.

As in all things biological and especially ecological, it is not complete due to the complexity of biological systems and even greater complexity of ecological systems. The ideas and examples are still a work in progress. However, as is self-evident, what is presented here describes and

explains the much safer use of Native Bioeradicants as an alternative to the dangerous practice of Classical Biocontrol.

Classical biocontrol – the introduction of non-native organisms in the attempt to reduce the effects of other introduced non-native organisms on ecosystems. This is a losing proposition as

the goal is not to remove the problems, just reduce their effects. At the same time there are unforeseen negative effects which cannot be predicted in the local and extra-local ecosystems in

which they are introduced through genetic or behavioral changes in native organisms in the ecosystem and in the non-native biocontrol such as the non-native biocontrol changing food

sources to native organisms, acting as a food subsidy for native organisms which unbalances the native food web with multiple possible consequences, competition for nesting sites, breeding

resources or any other resource with which it is in competition with native organisms, introduction of disease(s) to native organisms which may cause their extinction, … . Introducing the non-native invasive induced genetic and behavioral changes in native organisms. Therefore introducing another non-native to try to correct the prior problem will also induce genetic and

behavioral changes in the native organisms.

Bioeradication – The extinction of a non-native (invasive) species from an ecosystem using native organisms. This is a winning proposition as the goal is the regeneration of the ecosystem by eliminating the non-native problem from the ecosystem using native organisms which minimizes the potential problems associated with the addition of non-native organisms as potential controls.

Enemy Release Hypothesis (ERH) – Immediately when removed from its home ecosystem an organism takes only a small fraction of its biocontrols (and competitors) with it. During transport and when introduced into a new ecosystem other biocontrols (and competitors) drop out, further reducing the number of control organisms. It is the disease/pest/competitor version of the Founder Effect in which a small segment of a population immigrates to a new location, taking only a small subset of the original population’s genes with it. As in the Founder Effect, individuals (control organisms and competitors) may continue to drop out due to random chance or environmental unsuitability, while others adapt to the new conditions with unpredictable consequences. The final effect is the elimination of many of the restraints which prevented the non-native organism from taking over its home ecosystem.

This frees the non-native from many of its health and competition issues and allows it to focus on growth and reproduction in the new ecosystem. This is one of the major reasons that an invader can out-compete natives. Natives are kept in balance with the rest of the ecosystem due to direct and indirect native competitors and native organisms that use the native as an energy source.

Evolution of Increased Competitive Ability (EICA) – This starts on at the beginning of the introduction to a new ecosystem. It is most strongly seen on the front end or beginning of the Gaussian curve of an invasion. It is the genetic shakeout where genes and genotypes that are unfit for the new ecosystem go extinct. At the same time, genes and genotypes that increase the fitness/invasiveness of an invader increase or develop and proliferate. This is parallel to the Founder Effect in populations. The beginning is at removal from the original ecosystem and transport to the new ecosystem as even this requires special adaptations. However, it most strongly develops from the moment of introduction to the new ecosystem and through the early stages of logarithmic expansion. The process continues throughout its residency in the new ecosystem until it becomes extinct by a native (system) which evolves to drive it extinct through competition, herbivory, disease or any of numerous other processes alone or more likely as part of or in cooperation with other processes.

Bioeradicant – Any native organism in any time frame from seconds to centuries that partially or fully inhibits a non-native organism and helps to drive it to extinction. Unfortunately this is not the goal of using non-native biocontrols on non-native invasives. They are looking for control, not extinction of both of the introduced species (control and invasive) and groups of species.

Bioeradicant system – A group of native organisms which through any biological relationship

and time frame partially or fully inhibits a non-native organism to the point it is driven to extinction.

Direct bioeradication – This is the use of a native organism or native organism system as a bioeradicant for a specific organism. In the case of Ailanthus altissima it may be introducing a native wilt pathogen such as Fusarium oxysporum or Verticillium dahliae to work with Aculops

ailanthii and Atteva aurea.

Indirect bioeradication – Providing the native resources such as food, breeding sites or shelter needed for a native bioeradicant or bioeradicant system to develop at a specific location for a

specific organism. This may be nectar sources, sheltering plants, mutualistic fungi, water source or … .

Bioeradication garden – A form of Indirect Bioeradication which is a garden of local native plants that provide a resource at any life stage that a native bioeradicant needs to be effective as a bioeradicant such as food, egg laying sites, overwintering sites, protection from predators, …,

Bioremediation can be a direct result of using a bioeradication garden by providing native organisms to replace the extinct non-native organisms.

Bioeradication resource – Any naturally occurring environmental resource a native bioeradicant

needs to be effective as a bioeradicant.

Resource use – This is the use by a native bioeradicant of a native or non-native resource. In the case of a non-native resource it takes time to adapt to using it through either learning to use it

(behavioral changes) or genetic changes, often both.

Resource familiarity – This is the amount of use of a resource by a native bioeradicant. In the case of non-native (invasive) resources it requires time for a native bioeradicant to adapt to it through either behavioral or genetic changes and begin driving the non-native to extinction.

Resource heritage – This is the passing on of a behavioral and/or genetic adaptation to a

resource by a native bioeradicant. This can be through learning, by genetic change or more probably a combination of both. It can spread through a species horizontally as one organism

learns from another or vertically as it is passed on to/through offspring through learning or genes.

Mutualism – Two or more organisms which cooperate to the benefit of each other. Bioeradicant

systems reflect this at different levels of relationship by eliminating a non-native from the ecosystem through (unintended) cooperation, different feeding strategies which enhance the

success of both species, behavioral adaptations or other strategies.

Competition – Relationships where certain organisms benefit through a variety of mechanisms to the detriment of others without necessarily using them as an energy source. This is an

essential element in bioeradication.

Herbivory, predation and parasitism – Relationships in which one organism or groups of organisms benefit by using other organisms as an energy source. This does not imply that all the benefit accrues to the herbivore, predator or parasite as there are often unseen benefits to both

organisms.

Direct competition – When an organism competes directly with another organism for a resource. Examples are two species of bees competing for a pollen source or a vulture and a

crow competing for an animal carcass. This is good if a native bioeradicant is successfully competing with a non-native organism and driving it to extinction. It is bad when a non-native is

driving a native to extinction.

Indirect competition – Positive is when an organism provides a resource needed for another organism to compete with a native or non-native organism. Knowing how to manipulate this is better than introducing a non-native organism into an ecosystem to control another non-native organism. An example is providing plants as egg laying sites for a native butterfly that competes with a non-native species such as the cabbage moth. Indirect Bioeradication can be a result of

this.

Negative is using a native organism to destroy a biological resource that a non-native organism needs which is in competition with a native organism. This may be planting native wildflowers in

a meadow to remove a grass needed by a non-native moth such as food, egg laying sites or shelter.

Resource enhancement/depletion – This is enhancing a resource needed by a native bioeradicant to help it eradicate a non-native species. By changing the conditions in an

ecosystem, the competitors’ dominance and status in the ecosystem changes. This may be a change in the humidity which changes the fungi associated with a competitor, either increasing

or reducing its ability to compete and function in an ecosystem. Or changing the conditions needed by a native competitor on that competitor. It is similar to a domino effect except that it

is about changes on one component of an ecosystem causing changes on another organism which affects that organism’s ability to survive and/or compete in that ecosystem. This is a strategy which should be used carefully and with much forethought due to the very strong

possibility that by changing the abiotic environment, more damage than good can be done. The same is true with the biological components of an ecosystem. One change can cascade

uncontrollably in an unforeseen direction which causes more harm than the original problem did.

This may be as simple as removing a dam to allow fish to migrate along a river corridor, adding

stepping stones in a creek to facilitate drinking by native animals or changing a meadow back to a flooded meadow to remove burrow sites.

Bioremediation – the use of native organisms to displace or replace non-native organisms as they are eliminated from an ecosystem. This is an expansion of the traditional definition of bioremediation into an ecological usage beyond the microbial level. Whereas, traditional

bioremediation is the use of microorganisms to mitigate chemical or organic pollution, this is the use of the term to mean use of native organisms to restore an ecosystem during and after the

removal of a non-native organism or non-native organism system.

The use of Indirect Bioeradication is one inherent way of doing this as it places native species which already have a place in the ecosystem back into the natural succession process. This fills

the ecosystem’s temporal and spatial gaps left by the eradication of the non-native species. This in turn prevents reinvasion by non-native species.

In Bioeradication we are trying to understand all the relationships within an ecosystem to find native organisms to hinder and eradicate non-native organisms. We are looking more for

systems composed of many organisms than single organisms or “magic bullets” as systems are more stable due to their complexity and composed of multiple strategies for destroying non-

native invasives. Therefore, bioeradication systems are more able to adapt to changing environmental conditions, the changing gene structure and the changing strategies used by an

invasive non-native.

Adaptation of Novel Weapons or their development is a major component of EICA in the ongoing and continual changes of adaptation to changing ecosystem conditions by non-native

species. Bioeradicants are able to neutralize the Novel Weapons by being immune to their effects due to experience with natives using the same or similar “weapons”, adapting present defenses or by developing new defenses. The more native congeners or confamiliars of the

invasive the native bioeradicant uses, the more apt it is to have the genetic and/or behavioral tools to pace with and out pace the changes in the non-native. Therefore, also the larger the

number of congeners and confamiliars in an ecosystem, the greater the chance a bioeradicant/bioeradicant system will develop. This is due to potential bioeradicants being adapted to the defenses of native congeners or confamiliars and having been potentially

exposed to similar “weapons” or the genes responsible for them. Thus the defenses, the ability to adapt already in place defenses or the ability to develop new defenses to Novel Weapons is

already in place in bioeradicants. The result is either the non-native is outcompeted by the bioeradicant or the non-native is used as an energy source by the bioeradicant. Most probably it

is a combination of both that will be most effective.

ERH and EICA are continuing processes throughout the residency on non-natives in the new ecosystem, including failed introductions. The evolution of bioeradicants begins at the moment of introduction of the non-native. After the non-native is eradicated, the native bioeradicants remain in the system with genes and physical/chemical structures already in place should the non-native or a relative try to reenter the ecosystem. This allows the native bioeradicants to

swiftly deal with new attempts of invasion by the non-native or its close relatives.

Bioeradication starts being effective when native bioeradicants evolve beyond the effects of ERH and faster than EICA can keep pace with the evolving new defenses and adaptations of native organisms and the changing conditions which cause them to either use the non-native as an

energy source or out-compete it for an essential resource.

The EICA/Bioeradicant process is a continuing process until the non-native goes extinct in the invaded ecosystem.

Combined, EICA and ERH explain the first parts of an invasion, up into the logarithmic growth. What they do not explain is the evolution of native organisms into bioeradicants and

bioeradicant systems when population densities begin to level and crash at similar rate as their increase in the ecosystem. When plotted, this will be similar to a bell curve or Gaussian

distribution as natives adapt to the non-natives and drive them to extinction by outcompeting with them for resources or by the non-native becoming an energy source for the bioeradicant.

The highest probability is that a bioeradicant system develops which contains multiple organisms using multiple strategies which outcompete the non-native for a critical resource(s) and/or use it as an energy source. That this will be a system means that it will be slower to form and become

obvious due to the increased complexity as compared to a biocontrol or a bioeradicant, even though individual components will develop at different rates and become apparent at different

times, seasonal and temporal.

There is a critical point in time or critical population density of the non-native needed for a bioeradicant/a bioeradicant system to develop and target the non-native. Once this point is

reached there will be decreases in the population size and density of the non-native in line with a Gaussian curve, i.e. a temporary continuation of the increase in population size of the non-native followed by a plateau or peak and then a decrease as the effects of the bioeradicant

(system) begins to take effect. The more native congeners and confamiliars of the non-native and its biocontrols, the potentially lower the critical point will be on the curve both in time and the population density of the non-native. There is also a spatial component in that the closer

spaced members of the non-native are, the easier it is to spread genes, behavioral patterns and members of the bioeradicant (system) to other individuals in the non-native population. In

other words, critical densities may be the overall population size of a non-native organism in an ecosystem along with the population density of organisms in a set area and the density of the

potential bioeradicants. This is seen with Lonicera morrowii, Rosa multiflora and Ailanthus altissima. All three invasives not only have a high density of individuals in an ecosystem, but

have dense stands of individuals. Thus the spread of the bioeradicants, their genes and behaviors are doubly enhanced due to stand density and the overall density of the invasive in an

ecosystem.

The biggest question asked about bioeradication is why it has not been seen and recorded? The answer is threefold. The first reason is that we are not looking for it. Second, bioeradication

may happen before we are aware of a problem it took to extinction. Third, is that this may take many years to hundreds of years to happen. In essence, the process of bioeradication may

happen too fast to be noticed. Or, it may happen too slowly to be noticed by a researcher or school of researchers.

The most important part of what is being presented is that it is not complicated. Humans have the horrid ability to complicate the simple and obvious. They also have the destructive desire

and ability to tinker. After they are done tinkering, bad data is gathered and called good because the numbers meet certain parameters. Whereas, if the tinkering was not done in the first place, there is no need to tinker again and the data gathered is actually good. A prime example of the tinkering mindset is seen in my health issues – diabetes and bipolar II. For diabetes, instead of eating healthy, avoiding toxic chemical rich foods and exercising, medications are prescribed,

artificial sweeteners are suggested and a whole industry is developed that would not be necessary if we did not tinker with the foods in the first place and went out for a walk every day.

The same is true with bipolar II. Instead of dealing holistically with the condition, we are fed medications until we are insensate and celebrate because we have “controlled” it. We do the same with ecological systems, tinker until it breaks and then tinker again to try to fix it. Then

celebrate our apparent successes.

Finally, biology and ecology are tremendously complex. Reducing phenomena down to one or two rules or variables is unrealistic. As scientists, we search for absolute and straightforward answers in the simplest terms. Unfortunately, for every apparent absolute rule in biology and

ecology, there are many shades and variations. What is written here is an outline in the broadest sense of what happens in an ecosystem, not finitely detailed descriptions with all the variables. For instance, with Ailanthus altissima, the herbivorous insects which feed on it and the pathogenic fungi which infect it require different conditions to flourish. What is true in a

field is not necessarily true on the edge of a wetland where there is more available water. Low moisture favors the herbivorous insects. Higher moisture favors the pathogenic fungi. Both sets

of organism are present in both situations. However, the effects of each organism differ in the different conditions, even though the combination is often fatal in both situations to Ailanthus

altissima.

Constructive input is asked for so this concept can be strengthened and safer practices developed than are presently used.

The Slideshare.net presentations are at:

http://www.slideshare.net/hacuthbert/gardner-biocontrol-nenhc-2013http://www.slideshare.net/hacuthbert/gardner-ailanthus-nenhc-2013

Now it is time for me to take a walk in the woods.

Richard Gardnerrtgardner3@yahoo.com

June 19, 2013