**Responses to some of the (best) questions concerning the **

**Discussion Paper on the Screening Process.**

Richard Orr

August 23, 2000

"*Behold the turtle, he progresses only when his neck is out.*" \-- Bill
Denision when commenting on the discussion paper

I would like to thank those that commented on the discussion paper.
Those questions that I felt needed a response are summarized below. Some
of the editorial comments that I received were incorporated directly
into the discussion paper.

The response to these questions are mine and should not be attributed to
the NISC, its staff, or to any other Federal agency. However, it should
be recognized that after August 25, 2000 the comments and discussion
paper will be handed over to the NISC to do with as they feel
appropriate.

\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*

**Question 1:** Although the paper mentions and grossly captures the
uncertainty of the information used in the various steps in the process,
it appears that the uncertainty was not incorporated into the final
decision, what gives?

C **Answer:** This is correct, the screening process used in the
discussion paper attempts to grossly capture the uncertainty surrounding
the decision but does not use the degree of uncertainty in making the
final decision. Although the uncertainty surrounding the non-native
species needs to be communicated within the screening process, a
decision still has to be made regardless of the degree of uncertainty
involved. Capturing the uncertainty is important because it focuses on
what areas of the decision are the weakest and thus where new
information would be helpful. Uncertainty alone should not be used in
placing restrictions on the movement of non-native species because one
needs justification for government regulation or other actions that
imposes restrictions or burdens the American people. Uncertainty will
always favor non-regulation over regulation.

Many in the Invasive Species community wish the opposite because they
recognize that uncertainty raises the probability that the screening
process will demonstrate a higher failure rate on those species showing
a high degree of uncertainty surrounding their invasion biology.
However, this does not over ride the importance on providing
justification to restrict (regulate) the American people and uncertainty
is not likely to be accepted as adequate justification simply because
uncertainty falls on both sides of the argument.

Another argument for not judging an organism based on uncertainty is
that the screening process must treat non-natives as neutral (neither
good or bad). Nearly all non-native organisms will contain some degree
of uncertainty as it relates to its potential invasiveness. If
uncertainty is linked directly to identifying a non-native species as
invasive, then the neutrality of the screening process is compromised.

**Question 2:** Why was "non-native" and "invasive" concepts kept
separate when it would be possible to combine the two under a single
step?

C **Answer:** It is true that step 1 and step 3 could be combined into a
single step. However, I believe that this would not be wise. Much of the
misunderstanding surrounding the E.O. is reflected in confusing all
non-native species with invasive species. The E.O. addresses invasive
species which includes only a small handful of the total universe of
non-native species. If non-native species are beneficial or benign the
E.O. does not encourage, or discourage, their use, distribution, or
importation. The E.O. is only concerned with those non-native species
which could or have become serious problems (invasive species). I
believe that it is important to minimize this misunderstanding and
whenever possible keep the distinction between invasive species and
non-native species separate.

**Question 3:** The paper mentioned that the screening process needs to
be "socially and politically feasible"; should this also include
"humane"?

C **Answer:** I have no problem with adding the word humane. I would
like to believe that being humane is part of our social and political
environment and therefore its presence in the sentence is redundant, but
if this is not the case it needs to be said.

**Question 4:** The paper does not include the consideration of
secondary effects for either the "potential damage" or the "benefits".
These secondary effects are of importance and should they not be used in
a screening process?

C **Answer:** You will get no argument from me that secondary effects
can be important. The reason that I bypassed them in the hypothetical
screening process is that it compounds the complexity of the screening
process. If the screening process is too burdensome it will not be
implemented. For most non-natives the uncertainty surrounding primary
effects are uncomfortably great, while comments on secondary effects
become mere guess work. On the other side of the argument if secondary
effects have been demonstrated for a particular non-native species then
I would hope that it would be considered. Bottom line is that I have no
problem with incorporating secondary effects but I just can't figure out
the best way to do it without bogging down the process.

**Question 5:** Should not the region of the country that the introduced
species is going be considered important in a screening process?
Something that would be dangerous in the Southern States may not be in
the Northern States. Something kept in a personal aquarium is less
likely to be come invasive that something that is deliberately
introduced into a stream. Should these types of issues not be considered
before black-listing it and not allowing it to enter the country?

C **Answer:** I got a lot of variations on this theme. And I believe
that they are due to two misunderstandings of the screening process. The
first misunderstanding has to do with how screening processes work in
relationship to each other and the second misunderstanding is the
meaning of putting a species on a clean (approved) or dirty
(not-approved) list. Had I realized the amount of comments surrounding
these two issues that I was going to get, I would have presented these
concepts in more detail in the discussion paper.

**The use of risk filters in a risk screening system:** A single
screening process does not exist on its own but in combination with
other screening processes. Conceptually the risk screening system works
like a series of biological sieves. In the risk screening system the
first sieve (screening) has the largest entry screen holes (least entry
requirements) while each progressing screen has slightly smaller sized
holes (increased entry requirements). The first time an organism is
stopped by a screen then it can be allowed entry via the requirements
associated with that screen. The hypothetical screening process that was
presented in the discussion paper was a general screening process that
attempted to show how a screening process would function. It is most
likely too general to actually be effective, again its purpose was
demonstration not implementation. In addition, the screening system may
have different entry levels (or screens). For example each of the seven
screens below may be the start of a screening system designed to address
in total all intentional introductions.

a\) Screening system for the introduction of non-native biocontrol
organisms for terrestrial plant and animal pest control within the
continental United States.

b\) Screening system for the introduction of all fresh water and
terrestrial non-native

organisms (including biological control agents) into Hawaii and other
U.S. owned Pacific

Islands.

c\) Screening system for the introduction of all fresh water and
terrestrial non-native

organisms (including biological control agents) into Puerto Rico, Virgin
Islands and other

U.S. owned Carribean Islands.

d\) Screening system for non-native propagative plant introductions
within the continental United States.

e\) Screening system for non-native land animal introductions within the
continental United

States.

f\) Screening system for the introduction of non-native fresh water
organisms within the continental United States.

g\) Screening system for the introduction of non-native marine organisms
within the

oceanic, coastal and estuarine waters of the United States.

Each of these screening systems in turn would comprise a number of
individual screens which makes up the screening system. For example if
you take the screening system for non-native propagative plant
introductions within the continental United States, the

screening system might look something like this.

SCREENING SYSTEM FOR PROPAGATIVE PLANT INTRODUCTIONS

INTO THE CONTINENTAL UNITED STATES

1st screen for

Intentional introductions

unrestricted use/distribution

continental US

2nd screen 2nd screen 2nd screen

Intentional introductions Intentional introductions Intentional
introductions

for research only for biological gardens for commercial use

mitigation schedule A1 mitigation schedule B1 limited use mitigation
schedule C1

3rd screen 3rd screen 3rd screen

Intentional introductions Intentional introductions Intentional
introductions

for research only for biological gardens for commercial use

mitigation schedule A2 mitigation schedule B2 limited use mitigation
schedule C2

4th screen 4th screen 4th screen

Intentional introductions Intentional introductions Intentional
introductions

for research only for biological gardens for commercial use

mitigation schedule A3 mitigation schedule B3 limited use mitigation
schedule C3

not enterable or require not enterable or require not enterable or
require

special mitigation beyond special mitigation beyond special mitigation
beyond

standard filters standard filters standard filters

Each individual screen would have its own clean (approved) list, a gray
(status-undetermined) list and a dirty (unapproved) list. If the
non-native species ends up on the clean list then that organism can
enter based on the mitigation restrictions (if any) of that screening
process. If the non-native species falls on the dirty list then it will
move on to the next, more restrictive screening. If the organism falls
on the gray list area there are two choices 1) treat as dirty and move
on to the next screening process or 2) obtain more information and/or
conduct a more intensive risk assessment so that the organism can be
re-evaluated on to either the dirty or clean list of the current
screening process. Only after an organism passes through all of the
screening filters would it be prohibited entry or require special
mitigation beyond what the standard screening filters were designed to
provide.

**Question 6:** Why did the example in the screening process only cover
the continental United States and not Hawaii or the other offshore
territories and possessions?

C **Answer:** Insular environments are much more susceptible to invasion
than continental land masses. The screening process for Hawaii or other
insular environments would have to be more restrictive than the
screening process provided in the discussion paper.

**Question 7:** The paper (under the precautionary principle section)
recommends handling completely new importations differently from those
currently moving into the country. Is it possible to identify what
intentional introductions are currently moving into the country to make
this separation work?

C **Answer:** No, for the most part. For some categories of plants and
animals we do have a good feel for what is currently moving into the
country. For others we not only don't know what non-native species are
being imported but there exists no mechanism to find out. Just to
develop a system to determine what intentional non-native species are
moving into the country will be an additional burden on industry and
government. Even so, I believe that the separation between new and
current movement of non-native organisms should be kept as a justified
goal in the screening process because we simply cannot restrict an
imported invasive species if we don't know about it.

**Question 8:** The proposed process has an unknown error rate, in
addition it appears that its

decisions would be subject to the bias of the assessor(s) and that
different assessors could come up with very different rankings. Will
this type of approach be consistent and non-bias enough to be workable?

C **Answer:** It is correct that the hypothetical screening process has
an unknown error rate \-- hypothetical concepts always do. Careful
monitoring and reevaluation of the screening process would always be
necessary. The error rate will only come after testing (both before and
after implementation). Some standardization for ensuring that the
assessors are not biased (intentionally or unintentionally) will also
have to be worked out. The purpose of the rationale sections for each of
the critical steps in the screening process was to ensure that the
choices made by the assessors were transparent and consistent with the
information. The rationale section will be the place where the assessor
must show (demonstrate) his justification for the rank that he/she
provides in the screening process. When the assigned rank is not obvious
or requires a detailed explanation then the rationale section takes on
added importance.

**Question 9:** Why does the screening process focus on a white-list
approach which only allows entry for listed species?

C **Answer:** It does not \-- see answer to question 5.

**Question 10:** Is the regulatory structure in place to initiate a
screening process even if an acceptable process was developed?

C **Answer:** Yes, in part. Clearly there are regulatory (authority)
gaps but I believe that we are not in as bad of shape as many people
believe. Broad authority is often present but the incentives are
currently not great enough to trigger action within the various
government agencies or sufficient to form inter-agency coordination. It
is important to recognize that risk and screening processes are best
kept at the policy level and not incorporated directly into regulation.
The need for a screening/risk process may have to be stated in a
regulation. Regulations are not dynamic and a good screening/risk
process will have to undergo consent revision to meet the needs of a
dynamic trade industry and advancements in science and risk analysis. A
screening process will have to be constantly monitored and evaluated to
ensure that it is fair and equitable across the board. If the actual
screening process is locked into law this can not be accomplished.

**Question 11:** What does the word "establishment" mean in the paper
and in paragraph 4 of STEP 2 where it states "fit into one or more
habitats" is this referring to establishment?

C **Answer:** When used in reference to a species, establishment means
occurring as a reproducing, self-sustaining population in an open
ecosystem (Review Process ANS, 1996). When the paper states "fit into
one or more habitats" it was referring to establishment.

**Question 12:** When the screening process uses "no record of economic
impact". Does this mean no record because it has never before been
attempted (thus no information available) or that it has been widely
used and no negative impact has not occurred?

C **Answer:** It means both. When the paper uses "no record of economic
impact" it is referring to information that is available at the time of
the screening.

**Question 13:** Considering that the science on invasive species is
such that individual species predictions are, at best, gross and that
any screening process that errors too heavily in the direction on
invasive species paranoia resulting in the termination of 90% or even
10% of the current non-native species moving into the country is clearly
doomed for failure. Are we ready to start development on a screening
process?

C **Answer:** Yes. The difficulty of a problem is not a justification
for ignoring it and the need for protection from invasive species at
least justifies a serious look at some type of screening process.

**Question 14:** Must the discussion paper use words like precautionary
principle and lists? These have such emotional baggage attached to them.

C **Answer:** No, the paper does not have to use these particular words.
If better words are found that convey the same concept then the paper
should be re-worded. But keep in mind that a change in terminology
rarely solves a basic disagreement on an issue.

**Question 15: **On page four the paper talks about a fair balance
between the costs versus benefits. Is "costs" being used as an
alternative term for risks or to mean economic value?

• **Answer:** Neither, risk and costs are not equal and in this case
cost does not relate just to monetary loss. Risk is defined as "the
likelihood and magnitude of an adverse event". Costs, in this context,
captures the second part of the risk formula. Costs are equal to the
adverse affects in all forms (monetary, environmental, social, etc.).

**Question 16:** The hypothetical screening process is too quantitative.
Does not the use of numbers in the screening process implies a higher
degree of precision than can actually be achieved?

• **Answer: **The hypothetical screening process used in the discussion
paper is anything but quantitative. The process works by making
subjective (qualitative) choices based on current information and
assigning them a number for the sole purpose of ranking. Using numbers
to rank is not the same as using a quantitative relational set of
numbers derived from direct measurements. If the subjective values of
low, medium, or high are renamed 1, 2 and 3, that does not make the
original qualitative judgements quantitative. If the use of numbers in
the hypothetical screening process implies a greater scientific rigidity
than the process can provide, it was unintentional.

**Question 17: **Why did the hypothetical screening process not build on
the biological character-based screening processes currently being used
by some countries for evaluating plants for weediness?

• **Answer:** A small handful of screening processes exist for
evaluating plants based on their biological characteristics to determine
their potential for becoming weeds. The scientific verdict is not yet in
on this type of approach, but it seems to hold promise for evaluating
non-native plants introduced into disturbed environments. However,
caution should be exercised when elevating a process that uses a
species' biological characteristics to predict its invasiveness in a new
environment beyond primary producers and/or into areas where the natural
balance has been altered. The success of establishment is usually a
complex interaction of both the biological and the environmental
characteristics. This lock and key component for invasive species can
not currently be predicted (and probably never can be) based only on the
biological characteristics of the organism in question. Since the
hypothetical screening process was directed to all types of invasive
species (not just plants introduced to disturbed sites) I was reluctant
to include biological characteristics, such as number of offspring and
dispersal characteristics, in the criteria. What might be a good
biological characteristic to evaluate a weedy plant most likely would
not be for a tree fungal pathogen. Bottom line is that if the biological
characteristics of the organism is truly relevant for evaluating
potential invasiveness they should be used; but if not they should not.

**Question 18:** What is the next step for the screening process?

C **Answer:** The next step will be determined by the NISC with input
from the ISAC. My role of writing a paper on a screening process for
NISC discussion is completed.