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REVIEW PAPER

Assisted Migration in Normative and Scientific Context

D. S. Maier1 • D. Simberloff2

Accepted: 19 July 2016

� Springer Science+Business Media Dordrecht 2016

Abstract Assisted migration (AM), an ecosystem engineering technology, is

receiving increasing attention and significant support as a means to save biodiversity

in a changing climate. Few substantive, or not obviously deficient, reasons have

been offered for why pursuing this conservation goal via these means might be

good. Some proponents of AM, including those who identify themselves as

‘‘pragmatists,’’ even suggest there is little need for such argument. We survey the

principal reasons offered for AM, as well as reasons offered for not offering reasons.

As exemplified by the case for translocating whitebark pine, which may at first seem

especially strong, we note the incongruence of framing the goal of AM in terms of

‘‘saving biodiversity,’’ neglect of some crucial moral questions, marginalization of

normative and scientific context when AM is cast as the lesser of two evils in a

‘‘crisis,’’ doubtful validity and, in any case, marginal importance of arguments that

AM projects ought to be undertaken, inconsistent use of scientific facts, and

omission of science that counters sanguine assessments. All told—even in cases

such as whitebark pine for which AM may seem most defensible—there is little

reason to think that AM projects are good as means to ‘‘save biodiversity,’’ or good

as means to other goals that have accreted into arguments for these projects.

Keywords Assisted migration � Conservation � Ecosystem engineering �Biodiversity � Climate � Change � Whitebark pine

& D. S. Maier

[email protected];

https://donaldsmaier.wordpress.com/

D. Simberloff

[email protected]

1 8035 Yule Tree Ln., Sebastopol, CA 95472, USA

2 Department of Ecology and Evolutionary Biology, The University of Tennessee, 480 Dabney

Hall, Knoxville, TN 37996-1610, USA

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J Agric Environ Ethics

DOI 10.1007/s10806-016-9628-5

Author's personal copy

Introduction

Papers discussing assisted migration (hereafter, ‘‘AM’’) have proliferated –from

virtually nil before 2007 to hundreds per year recently (Hallfors et al. 2014, p. 5,

Fig. 2). Also known as ‘‘assisted colonization,’’ ‘‘managed relocation,’’ ‘‘species

translocation,’’ and other names,1 this type of project was initially proposed in a

conservation context by Peters and Darling (1985, p. 715), who suggested that such

projects might avoid extinction of populations or entire species facing climate

change. This change, they observed, may outpace the ability of some species to

sufficiently adapt in situ to new conditions—even if intensively modified for their

benefit—or to migrate sufficiently far to suitable new sites.

This original goal is now often characterized in terms of ‘‘biodiversity

protection.’’ However, ecosystem engineers already focused on rather different

goals quickly saw AM as means to serve these, too. AM is now also proposed as

means to preserve, establish, or enhance ‘‘ecosystem services.’’2 Although it may

not strictly qualify as AM in the sense that we discuss it, an instructive illustration of

ecosystem service-justified translocation is that of Castor canadensis, the North

American beaver, to myriad locales throughout North America. Once chiefly

appreciated as a slow-moving pelt—better worn than free to damage trees and

irrigation infrastructure—it is now translocated to provide soil erosion, water

control, and water storage services (Goldfarb 2015). The econometric end of the

spectrum of AM-facilitated goals is development of market-based goods, partic-

ularly in forestry (Pedlar et al. 2011), activities that differ little from longer-standing

practices of establishing commercial tree plantations (Aubin et al. 2011).

Back on the species conservation end of the spectrum, stripped of the

requirement that the threat be specifically climate-related, similar conservation

goals have long been discussed (for example, Dodd and Seigel 1991) in terms of

head-starting (bolstering populations from captive-raised early-life-stage stock),

relocation (moving organisms out of harms’ way typically to another part of their

historic range), repatriation (bolstering existing populations or reintroduction), and

translocation (AM without the requirement for climate-change-induced stress).3 In

fact, the different terms applied to AM-for-conservation stand in many-to-many

correspondence with the different kinds of project to which these terms refer

(Hallfors et al. 2014, pp. 3–10). Differences mainly concern (a) the goal of AM, and

(b) the conditions under which AM is said to be warranted as means. In the latter

category, a principal line of demarcation hinges on whether transport of organisms

1 Hallfors et al. (2014) discuss the surfeit of names for assisted migration, none of which were mentioned

by Peters and Darling (1985). The pleas of some to standardize terminology—by attaching specific names

to specific kinds of projects that differ in goals or conditions imposed—have so far been ignored. Nothing

substantive is at stake in our choice of the name ‘‘assisted migration.’’2 Halfway to ecosystem services are ‘‘ecosystem functions’’ or functional properties of an ecosystem that

some ecosystem engineers want to engineer into some ecosystems that lack them. Among those who

advocate translocating organisms to bolster certain properties are Lunt et al. (2013). We remark on the

normative relevance of these properties in our later discussion of AM for whitebark pine.3 See Schwartz et al. (2012, p. 733, Table 1) for another tabulation of project types involving moving

organisms to some selected locale.

D. S. Maier, D. Simberloff

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transcends, rather than stays within, historical ranges (Seddon 2010). Another

concerns using captive-bred versus wild-born individuals. Hallfors et al. (2014,

p. 10) insist that AM meet another condition: that the organism must have been

capable of translocating itself, absent human-constructed physical barriers and time

constraints; Siipi and Ahteeneuu (2016) argue that the moral respectability of range-

transcending translocations increases by meeting this requirement. Aside from

overlooking substantial, non-physical barriers arising from human behavior, this

suggestion appears to disqualify many AM candidates—biodiversity that AM could

not save.

Our focus is mainly on AM in the original, conservation sense of Peters and

Darling (1985), as framed by many later proponents: ‘‘saving biodiversity’’ by

translocating individuals of species or populations to sites beyond their historic

range to stem their imminent demise because of human-induced climate change.

However, thoroughness dictates attending to other goals added to arguments that

start out about ‘‘conserving biodiversity.’’ Many of our observations about the

principal arguments on behalf of AM refer to the particular case of whitebark pine

(‘‘The Case for Whitebark Pine’’ section). That discussion is best understood with a

prior understanding of the general terms of the AM debate (‘‘The Terms of the AM

Debate’’ section) and the fragmented normative and scientific context that frames it

(‘‘Missing and Hazy Moral and Scientific Context’’ section).

The Terms of the AM Debate

The last decade’s plethora of concept and commentary papers on AM show it to be

largely accepted as a legitimate conservation tool—even by skeptics who merely

insist that AM meet certain ecological conditions (Hunter 2007; McLachlan et al.

2007; Hewitt et al. 2011). The debate saliently centers on the fact that AM targets

single species rather than entire ecological communities and that it retreats from the

traditional conservation approach of conserving species by maintaining the

environments in which they currently thrive. However, few commentators4 touch

on the central normative question: Is there moral warrant for rearranging the

planet’s biota as a response to climate change?

This reticence may seem perplexing in light of ubiquitous discussions about how

to decide whether to AM or not to AM. Some authors even delineate decision

procedures with flow diagrams (Hoegh-Guldberg et al. 2008) or decision-tree

graphs (Richardson et al. 2009), which, they allow, may sometimes compute the

answer, ‘‘undertake AM.’’ But they offer little basis for thinking that the

computational inputs are normatively important and hence that a computed decision

‘‘to AM’’ is right in the sense of ‘‘morally warranted.’’

Several errors may lead to misplaced confidence in decision procedures. One

arises from the mistaken belief that we ought to choose what we would choose by

following a good or even ideally rational deliberative procedure. This belief gets the

normativity backwards (Parfit 2011, pp. 62–63). In fact, we ought to choose what

4 The ‘‘Missing and Hazy Moral and Scientific Context’’ section takes up the exceptions.


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we have most reason to choose. While we may be more likely to uncover the most

important reasons and reach a correct conclusion if we deliberate in some ideally

rational way, the method is not what makes it right or how we know we’ve got it

right.

Another error, correlative to the last one, arises in pervasive calls to include as

many ‘‘stakeholders’’ as possible in deliberations; others, such as Klenk and Larson

(2013, p. 17), ‘‘recommend empirical research on stakeholder views on AC

[Assisted Colonization].’’ For their part, Hewitt et al. (2011, p. 2566) state:

We…place little faith in the potential for generalizable valuations of species

and suggest that focal species benefits may need to be placed in the context of

local and global stakeholder interest for particular AM proposals.

But contrary to what these and many others apparently presume, stakeholders’

views regarding some action are not importantly relevant to whether the action is

morally warranted. In fact, including certain stakeholders can, and not infrequently

does, lead to morally perverse decisions.5 That is why we don’t inquire about views

of slave-holding stakeholders over millennia to ascertain whether the practice of

slavery was morally justified in slave-holding societies.

Another, closely related error is evident in similarly widespread calls (Schlaepfer

et al. 2009, p. 471; Klenk and Larson 2013, p. 17) for ‘‘socioeconomic data.’’ These

data often refer to the aggregated desires of persons or cultural norms.6 But no

amount of sociological investigation into what people desire or what cultures

sanction can reveal whether what is desired or sanctioned is worthy of these

attitudes. As for economic data, they more narrowly aggregate the particular kind of

sociological data inherent in market transactions, which evidence the actual desires

(worthy or not) of parties insofar as they are willing and able to enter into such

transactions.7 These data therefore also have little normative relevance.

A similar though less obvious error concerns the normative relevance of

biological facts. It is beyond dispute that the rightness of a normative conclusion,

such as that some AM project ought to be undertaken, supervenes on certain

scientific facts or our best understanding of them. This is the science that the AM

literature endlessly sifts. It concerns (among other things) the existence and likely

prospects for some set of organisms in their current locale versus another, alongside

the likely ecological consequences of letting them be versus installing them

elsewhere. However, despite this supervenience, and even were the best scientific

assessments of all these factors certain (as they are not), no valid normative

conclusion (to AM or not to AM) can follow from them alone. Even if the

5 The worry that stakeholders with morally objectionable goals may prevail is not abstract. This,

precisely, has happened in the UN-affiliated Intergovernmental Panel on Biodiversity and Ecosystem

Services (IPBES). With destructive corporations included as ‘‘stakeholders’’, the IPBES have adopted a

framework that essentially places its imprimatur on those corporations’ destructive behavior (Maier and

Feest 2015). See also Maier (2016) on including stakeholders.6 The term ‘‘socioeconomic data’’ may also refer to factors other than actual desires and cultural norms,

which are normatively relevant—for example, human safety.7 That economic value reflects not just willingness but ability to pay entails that it disproportionately

represents the actual desires of the rich.


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population of an organism in question would assuredly perish if let be, even if it

would assuredly flourish elsewhere as an evacuee, and even if the ecological

changes that it brings to its new home would assuredly fall within the tolerances of

some AM engineering specification, these considerations alone would not tell us

whether we ought to undertake it. That determination hinges on the answers to

multiple normative questions. These include, most basically, whether we ought to

act to continue the existence of a population (or species) on these terms. No amount

of biology alone can answer this or related normative questions.

The aforementioned and other proposed decision procedures assume the form of

cost-benefit analyses (CBAs), the terms of which dominate assessments of AM. As

Hewitt et al. (2011) put it, ‘‘what is ultimately at stake [is] the relative benefits and

risks of AM.’’ These analyses attempt to account for the likelihood of beneficial and

harmful outcomes to arrive at some expected net value for an AM project, while the

term ‘‘risk’’ is used to mean ‘‘the likelihood of some harmful effect.’’ However,

while these assessments speak of AM’s harms and benefits, those proposing them

hesitate to offer any reason to think that what they call the ‘‘benefits’’ of AM are

good things, worthy of bringing about; or that certain other consequences of an

organism’s translocation are ‘‘harms’’ that we ought to avoid.

This last observation is crucial. Even such narrowly utilitarian analyses as CBAs

do not get off the ground until the benefits and costs that matter are identified. But

proposed CBAs for AM lack serious discussion of what or ‘‘whom’’ is benefited or

harmed, and consequently whether it is plausible to speak of benefits and harms to

these unspecified subjects, or whether these kinds of benefits and harms really

matter. Classical utilitarians—for example, Jeremy Bentham and Peter Singer—

focus on the sentience of individual organisms. But species (the presumptive

beneficiaries of AM) are not sentient, even when their individual members are. And

a risk of something that doesn’t matter also doesn’t matter.8

Finally, it seems necessary to mention an obvious normative truth: The

(sociological) fact that some parties have engaged in a particular type of behavior

is normatively irrelevant to whether or not it is permissible for us (or others) also to

engage in it. Some authors ignore this fact, for example, Schlaepfer et al. (2009,

p. 472), who cite the facts: ‘‘Humans have historically moved organisms for a

variety of purposes, and at least two species have already been moved under the

aegis of assisted colonization’’ as reasons that translocations for conservation

purposes should not be proscribed. Indeed, as Klenk and Larson (2013, pp. 16–17)

observe, many proponents appear to be considerably more concerned with who gets

to do AM projects than about whether they ought to be done.

Other papers evidence awareness of the need to address ‘‘ethical challenges,’’9

but show limited awareness of what these normative challenges are or how to

address them. Schlaepfer et al. (2009, p. 471) mention ‘‘divergent value systems.’’

But immediately afterwards, they err in many of the above-mentioned ways, stating

8 For example, I am justified in my moral unconcern about the risk of my stepping on sidewalk cracks as

I stroll downtown.9 The phrase ‘‘ethical challenges’’ comes from the title of Schwartz et al. (2012), discussed just below in

the main text.


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that this divergence of actually held values calls ‘‘for a framework that integrates

biological information and sociological data’’ to determine if ‘‘biological, social and

economic benefits outweigh costs.’’ On this basis, they say, ‘‘stakeholders’’ should

make a determination. Schwartz et al. (2012) bring attention to some of the

legitimate ‘‘ethical challenges’’ of their paper’s title—perhaps most usefully to

moral hazards (Schwartz et al. 2012, p. 727), which most others ignore. But beyond

that, they do little more than summarize the terms of the debate as it has actually

played out without attending to their many deficiencies.

Among those who signal awareness of the need to place AM on some firm

normative footing are Minteer and Collins (2010, 2012) and Minteer (2012). Indeed,

Minteer and Collins (2010, p. 1801) see themselves as pioneers of a ‘‘more dynamic

and pragmatic approach to ethical analysis’’—the environmental equivalent of

biomedical ethics (Minteer 2012, p. 142 and elsewhere). According to them

(Minteer and Collins 2010, p. 1803), their ‘‘pragmatic’’ approach should supersede

traditional ethics, which get bogged down in sorting through the normatively

important reasons that may proscribe AM in increasingly complex situations:

What is needed, we believe, is the development of a more pragmatic ethics of

species relocation under climate change. This pragmatic approach to ethical

decision-making in ecology and conservation should be less preoccupied with

whether such efforts should be undertaken in the abstract. The attention should

shift to outlining the conditions under which managed relocation should be

considered as a realistic option and what criteria are relevant to distinguishing

‘‘good’’ from ‘‘bad’’ relocation proposals, and evaluating good and bad

relocation efforts on the ground.

In these words, Minteer and Collins urge that we forgo any attempt to answer ‘‘in

the abstract’’—that is, by valid normative reasoning from credible, generally

endorsable, and generally applicable moral principles—whether AM serves any

worthy goal or, if it does, whether it is a morally respectable practice. This

exhortation overlooks the fact that a good way to perform an act that we ought not to

perform is not equivalent to performing a good act.10 Minteer and Collins are

nonetheless likely correct to think that their pragmatic ethics melts away many of

AMs complexities by focusing on ‘‘realistic options,’’ a phrase that appears to mean

‘‘what ecosystem engineers can (rather than should) do.’’ Assessing our capabilities

is often simpler than assessing our moral permissions and obligations. Minteer and

Collins are hardly alone in calling for a ‘‘pragmatic’’ approach to AM—either out of

apparent unawareness of the importance of ensuring the moral worthiness of

projects or because normative principles bearing on AM just seem too difficult to

work out. Among the popular interpretations of this sentiment is the view, expressed

by Hewitt et al. (2011) (above), that one should simply determine what stakeholders

want.

It is important to highlight another, prominent, and normatively confounding

element in the terms of the AM debate—namely, the classification of certain

‘‘benefits’’ (within AM’s CBA framing) by reference to ‘‘ecological value,’’

10 For example, torture by even the best methods does not make its practice good.


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‘‘ecological importance,’’ or conducing to ‘‘ecosystem integrity,’’ which some say

(Sandler 2010, p. 245) is ecological value or a salient component of it. To say that

the presence of an organism in some ecosystem has ecological value merely stakes

the claim that there is something good about this organism’s presence there. It says

nothing about what is good about that presence; nor does it provide any normatively

relevant reason for believing it good. Rather, such a claim merely marks the place

where we are owed these dual accounts.

Not infrequently (as in the case of whitebark pine), ‘‘performing an ecosystem

function’’ is offered as the account of what is good, and ‘‘conducing to ecosystem

integrity’’ is offered as the missing reason for why it is good. But these stock

answers merely pass the normative buck or raise without answering other, equally

difficult questions: Why is it good that an ecosystem have certain functional

properties but not others? What special goodness arises from the fact a particular

organism plays a causal role in some functional property? And insofar as

‘‘ecosystem integrity’’ is taken to mean ‘‘the condition of retaining certain state and

functional properties,’’11 why is this sort of ecosystem stasis good?

Finally, no adequate characterization of the terms of the AM debate can omit

mention of a pervasive and incorrect assumption at its foundation: that if some

thing, such as a species, is good or worthy of respect, then its continued existence

must be good and therefore we should act to protect it. For example, Hale et al.

(2013, p. 77) state, ‘‘moral systems that privilege individuals, or species, or even

ecosystems essentially leave little choice but to preserve those things of value or

with status.’’12 But this assumption is not generally true—even for ‘‘things’’ such as

persons whose moral value is less controversial than that of species. If some very

good person is reduced to a slide towards death and so incapacitated that she no

longer can do anything that she finds important, then these circumstances give

reason to think that, while she and her life should be respected for all that it is and

has been, her continued existence is not necessarily good, and therefore it is possible

that it should not be promoted by acting so as to prolong it.

Missing and Hazy Moral and Scientific Context

Few papers engage substantively with AM’s important normative questions—even

when representing that they do. Albrecht et al.’s (2013) titular promise to address

‘‘the ethics of assisted migration’’ devolves into ‘‘arguments’’ that largely consist of

repeating the phrase ‘‘we argue that…’’ This phrase, it soon becomes evident, means

‘‘we suppose, without giving reasons for supposing, that…’’ In this way, they (p.

835) ‘‘argue that’’ species have ‘‘intrinsic value’’ and ‘‘argue for’’ rules of intrinsic

11 The ubiquitous phrase ‘‘ecosystem integrity’’ is used in multifarious ways, often as an approximate

synonym for ‘‘ecosystem health.’’ These two phrases jointly embody a concept that formerly was referred

to as ‘‘the balance of nature.’’12 With his suggestion that the value of species is essentially intertwined with its particular relationships,

Sandler (2010, 2012, 2013) is one of the few who not only avoids but also rejects the assumption that the

goodness of a thing entails a duty to promote its continued existence: For him a species’ continued

existence is not good absent these relationships.


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value transfer—for example: ‘‘species… have intrinsic value as do, by implication,

the ecosystems/habitats within which they live.’’

Siipi andAhteeneuu (2016) (mentioned in ‘‘The Terms of the AMDebate’’ section)

suggest that AM projects may achieve more secure moral footing by taking into

account the translocated organism’s range and the ‘‘naturalness’’ of its inhabiting the

target locale. But they ground this suggestion in an implausible view, which

normatively privileges AMprojects on the basis of an arbitrary, counterfactual kind of

historical mimicry—not of some past state, but of ecosystem demographics that, it

might be conjectured, would have obtained had people changed the climate but in no

other (physical) way constrained the movement of organisms.

The most comprehensive normative assessment of AM remains that of Sandler

(2010, 2012, 2013). The most significant effort to supplement and challenge

Sandler’s work is the attempt by Palmer and Larson (2014) to mine the high-profile

AM proposal for whitebark pine for additional normative perspective. We address

the case of whitebark pine in the next section. However, even counting these best

efforts, important normative questions connected with AM remain unasked; and

important normative context is obscured by virtue of how questions that are asked

are framed.

One would be hard-pressed to find a paper on AM that does not set the context as

a world in which the changing climate is devastating biodiversity. In this setting,

AM is billed as an important remedy and, not infrequently, a principal means to stay

a train wreck of extinctions. Yet there is little reason to think that even the most

extravagant deployment of AM technology could live up to this billing and much

reason to think it cannot. Even if all nature conservation resources on the planet—

scientists, time, money—were channeled entirely into AM projects, and even if

every one ‘‘succeeded’’ in the sense of establishing an appropriate population—not

too many, not too few—in target locales, no one could credibly claim that this

would affect more than a handful of species.

The false billing reflects widespread failure to take into account the true ambit of

even one AM project (Dodd and Seigel 1991; Dodd 2005). The thought that AM

may play a major role in ‘‘saving biodiversity’’ is credible only on the presumption

that the bulk of the effort consists of transporting and releasing or planting

organisms; then repeat for the next project. In reality, those sizable efforts may be

dwarfed by preparatory investigations13 combined with indefinitely extended

monitoring and management of the target locale for the sought-after, appropriate-

sized population of translocated organism that achieves true establishment without

invasiveness.14 Preparatory investigations could take many years; ongoing

13 While the need to research and thoroughly understand diseases transmitted by translocated organisms

is often acknowledged, Dodd (2005, p. 268) highlights other, seldom acknowledged investigative

requirements regarding: the causes for decline (some of which may be masked by the most obvious ones);

the habitat, demographic, and biophysical factors that constrain every stage of the organism’s life history;

and the organism’s population genetics alongside (for many animals) its social structure. Pedlar et al.

(2011, p. 766) suggest how formidable is the investigative task for trees when they state, ‘‘the existence of

established provenance trials, seed transfer guidelines, seed procurement systems, and plantation

establishment protocols makes AM considerably more feasible for most commercial tree species than for

most species of conservation concern.’’14 A translocated organism’s invasiveness can manifest only after decades (Simberloff 2013, pp. 92–96).


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monitoring must span multiple generations of the translocated organism. For some

organisms (such as whitebark pine) this might exceed the span of a biologist’s

career.

Even such enormous efforts may fail more often than they succeed. Among

translocated reptiles and amphibians, Dodd and Seigel (1991, p. 340) report success

less than one-fifth of the time, considered by species, and that the success rate

‘‘lowered considerably’’ when tabulated by project. To this they add, ‘‘no RRT

[repatriation, relocation, translocation] program has yet established a self-sustaining

population of snakes, turtles, frogs, or salamanders.’’ Perhaps some organisms just

don’t transplant well. Great disregard for this hard reality is represented by authors

(among them Albrecht et al. 2013, pp. 838–840) who suggest that more or less

entire ecosystems might be ‘‘transplanted,’’ then intensively managed in perpetuity

to prevent such undesired interactions as translocated organisms eating long-time

residents.15

These considerations point to considerable shrinking of AM’s capacity to save

species or populations. This circumstance gives rise to a moral question that has

received little or no serious attention: On what morally respectable basis might the

necessarily tiny contingent be selected? One might initially think that a normative

model for this situation is: one is on a life raft surrounded by drowning people—far

too many for the raft and none of whom, in any normatively relevant respect

(distance from the raft, difficulty of reaching them, even goodness as human

beings), have any special claim to be hauled aboard. In such a situation, we clearly

should do something and not remain mired in deliberation and choosing none for

lack of a basis for choice (the classical Buridan’s ass parable). Rather, without delay

or further deliberation, we should haul as many of them—any of them!—as we can

to safety.

However, the foolishness of inaction by Buridan’s ass does not justify foregoing

sober deliberation about slots on AM’s life raft because it floats in importantly

different normative waters. As just observed, no AM project (or no responsibly

conducted one) can be launched by just grabbing available plants or animals from

one locale and then installing them in another. The deliberative space required for

planning projects with such scope, complexity, and requisite commitment is also

ample space for deliberating about which species (or populations) we ought to haul

aboard. We do have time to ask: how should we choose in a morally

respectable way?

AM advocates are not without answers. One is: on the basis of services they

might provide to people. Of course, this response eliminates almost all species and

populations, including essentially all that are rare or endangered. Another is: on the

basis of how strongly public sentiment can be mobilized to back such a formidable

undertaking. This answer would likely finger large, charismatic animals. It would

15 It is important to note that our complaint about the naıve pretensions of AM as a significant means of

‘‘saving biodiversity’’ is different in kind as well as in scope from the commonly voiced complaint that

devoting too many resources to AM might undercut other kinds of worthwhile conservation efforts. The

latter complaint is about misjudging the allocation of resources. In contrast, our complaint calls into

question that it is even possible for AM to accomplish what it is supposed to—even if all conservation

resources worldwide were dedicated to them.


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push aside creatures such as the Inyo Mountains slender salamander (Batrachoseps

campi) and Devil’s hole pupfish (Cyprinbodon diabolis), hard-for-people-to-notice

mouse-sized or smaller animals such as the late-lamented Ash Meadows montane

vole (Microtus montanus nevadensis), and most creatures perceived as threatening

people. Bypassed as well would be the vast majority of organisms that are not

animals—including most plants (or any that lack iconic status) and fungi, not to

mention other eukaryotes that barely register in public awareness—slime molds,

flagellate protozoa, foraminifera, and brown algae—and non-eukaryotes: the

multitude of bacteria and archaea. If bolstering biodiversity is truly the goal, it is

difficult to believe that a scientifically credible and morally respectable basis for

selection is substantial contributions to the service economy or public popularity.

There may be other answers. But the very act of pitting one species or population

against others as more worthy for a place on a life raft itself raises vexing moral

questions. Without being asked and answered, yet more moral context falls away.

Some, such as Hewitt et al. (2011), even explicitly deny the need for ‘‘generalizable

valuations of species.’’

Another morally weighty, yet almost universally overlooked,16 problem concerns

the legitimate scope of AM’s application. If sanction for AM is conditioned on its

‘‘saving biodiversity from the effects of human-induced changes in the climate,’’

then its warrant would not extend to species or populations destined to wink out as a

consequence of other ‘‘insults,’’ or even to climatic changes that cannot be attributed

to humans.

One may better appreciate the moral importance of this last-mentioned problem

by reference to an extreme version of it: Few would argue that people should act to

ensure the continuation of every extant species and population. Even those who

believe species have a value that unconditionally commands moral respect are

disinclined to argue that this respect entails an unconditional obligation to do what

we can to circumvent all extinctions and population extirpations.

The case for the proposition that climate change—or more specifically, that part

of it attributable to people—is the principal factor in some species’ (or populations’)

demise is often very weak. Other factors—for example, removal of water from

rivers, pumping groundwater (affecting springs), habitat destruction, and so on

(Norment 2014)—are almost always present and often significant. Absent them,

climate change might not have a decisive role in the fate of many species or

populations. In many cases, it may in principle (not merely practically) be

impossible to answer the counterfactual question on which such a profound moral

demarcation is to be drawn: Would this organism have survived in a world absent

only changes to the climate attributable to human activities? An ethics requiring

action on the basis of impossible-to-attain knowledge should be regarded with great

suspicion. However, routine disregard for what is involved in meeting this epistemic

requirement fits the broader pattern noted above: minimizing the investigative

burden relating to AM projects, and minimizing or disregarding burdens of

monitoring and management that may span generations of ecosystem engineers.

16 Palmer and Larson (2014, p. 647) are an exception in allowing that whitebark pine is subject to a

‘‘multiplicity of threats’’, some of which may be considered independently of climate change.


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These above-mentioned deficiencies—mischaracterizing the proposition of

undertaking AM projects in normatively and scientifically important ways and

leaving holes in the fabric of AM’s moral and scientific context where normatively

and scientifically important questions should be asked—may be symptoms of moral

hazards latent in its ‘‘state of emergency’’ logic: (1) biodiversity is in crisis because

of climate change, (2) crisis conditions force dichotomous choices between evils,

and (3) because it is a crisis, we must choose the lesser evil posthaste. The principal

lesser-evil dichotomy—explicit or implicit in this framing—encompasses two

propositions: (a) Either we pursue AM projects or face losing many species. And

(b) ‘‘saving biodiversity’’ via AM (according to this logic) is better—a lesser evil

than—converting natural landscapes into eco-engineered ones.

This would be a grim choice indeed. It is therefore fortunate we are not actually

reduced to it. Both (a) and (b) are false as exclusive disjunctions: Regarding (a):

there are choices other than pursuing AM projects to spare species and populations,

if and when we have decisive reasons to do so. Most obviously, this often involves

paying more serious attention to the many (above-mentioned) factors other than a

changing climate that may be pushing species and populations to the brink. As for

(b): it is false by virtue of embedding the false assumption (discussed above) that

AM may ‘‘save biodiversity’’ or even play a significant role in achieving that goal.

Proposition (b) is especially insidious because it rationalizes the eco-engineering of

landscapes by merely and falsely posing eco-engineering projects as necessary

means for avoiding a bad state of the world. In this way, it subverts unencumbered

consideration of all the reasons that might make a world in which eco-engineering is

allowed on this or similar pretexts a bad world indeed.

Playing the crisis card also has the effect of appearing to justify short-circuiting

moral deliberation and carefully considered science—in other words, suspending

the customary norms and requirements of responsible action. Of course, genuine

crises do occur and some legitimately warrant such suspension. But not all of them.

Even supposing the state of the world’s biota constitutes a ‘‘biodiversity crisis’’, it is

doubtful that many AM projects qualify for shortcut evaluation: As recounted

above, they require far too much planning, investment in resources, and

commitment in time, effort, and careers to bring to completion. These traits do

not characterize a crisis where the need for snap decisions leading to quick action

may truly justify shortcuts.

The Case for Whitebark Pine

In his wide-ranging assessments of AM, Sandler (2010, 2012, 2013) surmises that

AM would ‘‘rarely’’ preserve the worth of a species on the basis of a wide-range of

widely held views about what makes a species valuable. However, Palmer and

Larson (2014) perceive that Sandler omits significant considerations that may tip the

balance in favor of pursuing AM in at least the high-profile case of whitebark pine

(Pinus albicaulis). Their work therefore merits special attention for its promise of

gleaning normative and scientific insight from detailed consideration of one,

seemingly attractive case for AM.


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Palmer and Larson (p. 659) characterize their study as ‘‘comprehensive in…taxonomy and analysis of values’’ and attendant to ‘‘ecological complexity.’’ These

qualities, they claim, qualify their analysis as a ‘‘model for future studies’’ of other

proposed translocations to spare species and populations from extinction from

human-caused climate change. In answer to their titular question, ‘‘Should we move

the whitebark pine?’’, they (p. 658) ‘‘consider that there are good reasons’’ to do so.

However, instead of realizing that promise, Palmer and Larson largely repeat

many of the recurring errors recounted above and add some others. And instead of a

comprehensive ecological treatment, they neglect crucial elements of the relevant

biology—particularly those that cast AM for whitebark pine in an unfavorable light.

Normative Deficiencies

AM as the Lesser Evil

When seriously considered, the ‘‘lesser evil’’ of nature’s large-scale rearrangement

may cast doubt that any AM project could be ethically justified. Yet Palmer and

Larson introduce their paper by effectively excusing themselves from addressing

this possibility because, ‘‘virtually everyone agrees that there will be at least some

cases in which assisted migration can be justified ethically’’ (643). In saying this,

they make the error, discussed in ‘‘The Terms of the AM Debate’’ section, of

presuming that sociological data can establish that some thing is good, some action

right, or some proposition true by majority vote.

Even Palmer and Larson’s non-normative assertion of near-universal agreement

is dubious—first, because no proper survey has actually been done and second, by

arbitrarily discounting views to the contrary. Biologists such as Ricciardi and

Simberloff (2009) (whom Palmer and Larson (643) themselves reference) forcefully

argue that conservation projects featuring mass movement of organisms always

involve unquantifiable risk. According to them, prudence therefore counsels for

always seeking other means that might achieve the same conservation end. Also,

some philosophers such as Maier (2012, pp. 312–315, Ch. 8) press the view that

AM’s engineered rearrangement of ecosystems damages rather than promotes what

is most valuable about nature. Palmer and Larson use of the phrase ‘‘virtually

everyone’’ is unwarranted.

Like many AM advocates, Palmer and Larson give the goal of averting extinction

top billing in their abstract and first paragraph. Yet, belying their claim for

comprehensiveness, they attend only peremptorily to alternative means to that end

(p. 647), highlighting eco-engineering proposals for whitebark’s current ecosystem

that involve burning, felling, or otherwise crippling that tree’s arboreal competition.

Other proposals they dismiss owing to the size of the commitment entailed, though

similar to that required for AM. This hasty dismissal of alternatives positions AM as

the lesser evil of an essentially dichotomous choice: Either undertake AM or

consign whitebark pine to extinction.

Yet other means of evading the species’ demise may be possible. Schoettle and

Sniezko (2007, p. 330) describe several potential strategies. In a comprehensive

assessment, Keane et al. (2012, p. 91) surmise, ‘‘We have the knowledge, skills, and


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experience to successfully restore whitebark pine forests across the species’ entire

range, even though blister rust and climate change will make this task more difficult

and complex.’’

To the more conventional conservation suggestions of these scientists may be

added horticultural propagation, which has often proven highly effective.17

Consider Monterey cypress (Cupressus macrocarpa), a tree that has but two, tiny,

relict ‘‘wild’’ populations in Monterey County, California. Specimens of that tree

have made their way via horticulture to other parts of California and Oregon, as well

as to Great Britain, continental Europe, Australia, New Zealand (where it has

naturalized), South Africa, and Kenya, where it is a commercial softwood timber

crop. Whitebark pine might, too, enjoy commercial success as a premier bonsai

plant alongside foxtail pine (Pinus balfouriana), which co-occurs with whitebark

pine in some high-elevation ecosystems.

Moreover, if preservation is the preeminent goal, then it is significant that, unlike

AM, horticultural promotion has a record of success. The ubiquity of Eucalyptus

spp. in California is highly visible evidence of enthusiastic planting of those trees,

beginning in the 1870s, to ‘‘improve’’ tree-impoverished landscapes.18 The wide-

ranging viability of this approach for whitebark pine is further suggested by the fact

that arboretums and gardens in disparate locations worldwide successfully nurture

specimens of this tree.19 Whitebark pine-enriched gardens and arboretums enjoy

another major advantage over AM: They are far more easily monitored and

controlled than intentional mass plantings in the very ecosystems that are the focus

of concern for out-of-control transformation.

Alongside horticultural propagation are other alternative means of forestalling

whitebark pine’s extinction, which center around alternate hosts—currants and

gooseberries (Ribes), lousewort (Pedicularis) (lousewort), and paintbrush (Castil-

leja)—for the white pine blister rust (WPBR, Cronartium ribicola) that plagues

whitebarks. Some alternate host of the rust is needed—as reservoir and dissem-

inating vector—to propagate the fungus among trees (Maloy 2001). This suggests

that locally thinning or otherwise curtailing these alternate hosts may sufficiently

diminish WPBR’s toll on some stands of whitebark pine to spare them.20 Also

significant is the success of a genetics program to develop rust-resistant western

pine (Pinus monticola). A similar program for whitebark pine—involving finding

resistant trees in nature and breeding them, then planting them in the existing

17 Mention of these other means should not be interpreted as advocacy.18 Jared Farmer (2013, Part Two, Eucalypts: The Taxonomy of Belonging) vividly recounts this tale.19 Many of these refuges—Dawes Arboretum in Newark, OH, Hoyt Arboretum in Portland, OR, Tilden

Regional Park’s Regional Park Botanic Garden in Berkeley, CA, and the United States National

Arboretum in Washington, DC—are far removed from the tree’s ‘‘native’’ montane haunts or any habitat

that even remotely resembles them. The websites for these facilities document their various specimens.20 The verdict on this possibility is not decided by the failure of a massive campaign in the early and mid-

20th century to eradicate WPBR throughout the United States by eradicating native and introduced

species of Ribes (Maloy 1997). This campaign, impossibly large in scope, was also waged in ignorance of

more recently uncovered (McDonald et al. 2006; Zambino et al. 2006) host capabilities of Pedicularis and

Castilleja spp. It also led to a successful genetics program to develop rust-resistant western pine (Pinus

monticola) (Maloy 1997).


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range—has begun (Schoettle and Sniezko 2007) and recently developed techniques

for genetic manipulation could accelerate it.

In short, Palmer and Larson neglect arguably more reliable, less disruptive, and

less costly means than AM of serving their first announced goal of saving Pinus

albicaulis. This neglect testifies to how powerfully the framing of AM as the only,

lesser-evil alternative to extinction may crowd out important context. Palmer and

Larson, however, also seek to paint the engineering of target ecosystems into

plantations of translocated whitebark pines as in fact not so evil. To this end, they

propose rather different goals that these plantations might be thought to serve,

though their connection to saving the whitebark pine is obscure.

Functional Properties

First among these newly added goals for AM is to endow target ecosystems with

certain functional properties, also termed ‘‘ecosystem functions.’’ If for some

unexplained reason Palmer and Larson reject the classification of gardens and

arboretums as ‘‘ecosystems,’’ then horticultural promotion of whitebark pine could

not, by their lights, serve this end. However, rearranging ecosystems to better

exemplify some set of properties that they would otherwise not have appears to be

the antithesis of any commonsense notion of conserving them. Palmer and Larson

counter this objection by trying to find something good in a re-engineered

ecosystem’s functional properties.

For their normative claims regarding these properties, Palmer and Larson take a

cue from Brian Buma’s suggestion (2013, p. 134) that ‘‘While species may indeed

lose their ecological connections via translocation and movement, they may create

new ones.’’ Following suit, they assert (p. 651), ‘‘The whitebark pine might be able

to forge valuable new ecological connections. This, they say, ‘‘would give us reason

to support assisted migration… based… on its contributory functions in a broader

ecological community’’ [italics added].

In these statements, Palmer and Larson construct ‘‘a reason to support

[whitebark’s] assisted migration’’ solely by attributing to it—in passing and with

no explanation or support—the normative property of being ‘‘valuable’’ to

ecological connections that whitebark will inevitably form to other elements in its

translocated locale. Reasons such as this one, derived solely from unsupported

application of a normative label, should be ignored. Similarly without merit is

Palmer and Larson’s related claim (p. 652), ‘‘relocated trees such as whitebark pine,

could be ecologically significant in positive ways in a new location’’ [italics added].

It, too, starts from the uncontroversial, non-normative fact that introducing

heretofore absent trees is likely to affect significantly an ecosystem’s ecological

properties. But we have no substantive reason to think this effect is good on the

basis of the mere appearance of the word ‘‘positive’’ with reference to it.

The normative ‘‘logic’’ here breaks down in other, independent ways. We should

all agree that any organism in any locale (historic or novel) will have some causal

influence on, be causally influenced by, or more generally, causally interact, and in

this sense ‘‘forge… ecological connections,’’ with other biotic and abiotic elements

in its environment. We also can accept calling these connections ‘‘functional


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relationships.’’ But for two reasons, this simple, universally true biological fact—

that any organism in any locale establishes these ‘‘functional relationships’’—

cannot possibly, by itself, make these relationships valuable: First, its universal

application to all causally interacting elements ensures that this fact cannot

distinguish functional relationships that are valuable from those that are not. And

second, there is no basis for thinking that the mere existence of some functional

relationship, independent of other properties, is always, by virtue of its existence,

good or better than its nonexistence.

On the other hand, compelling grounds exist for rejecting the thesis that the

functional relationships of a thing give reason to think that that thing is valuable

merely on that account. Were that thesis true, we would have reason to think that the

functional relationship of a slaveholder to his slaves contributes to the goodness of

those connections. Were it true of ‘‘ecological’’ functional relationships, it would

suggest that, for example, the functional relationships of Burmese pythons in

Florida’s Everglades to the raccoons, opossums, bobcats, rabbits, red foxes, and

grey foxes that they eat and whose populations they depress21 may be good on

account of those ‘‘valuable’’ connections. Or, returning to whitebark pines, suppose

that some eco-saboteur introduced a fungus other than white pine blister rust that

affected even the WPBR-resistant whitebarks in their new location. If functional

relationships were valuable merely by virtue of the ecological connections they

evidence, this new tree-fungus relationship would be valuable, too. But even if one

does not hold this questionable view, Palmer and Larson’s ‘‘logic’’ still applies with

equal force to rusts. After all, as some biologists have pointed out (Helfer 2014,

p. 771), rust funguses, too, ‘‘[regulate] the structure of natural ecosystems and

[influence] their functioning’’; they, too, are ‘‘[relevant] in provisioning ecosystem

services.’’ And rusts, too, might be vulnerable to the changes wrought by a changing

climate.

Ecosystem Services

The ecosystem services (Millennium Ecosystem Assessment 2005) that Helfer and

many others bring into the discussion of AM are generally understood to be

properties—functional or otherwise—of ecosystems (Hooper et al. 2005, p. 7) ‘‘that

either directly or indirectly benefit human endeavors.’’ With their own interjection

of this topic, one might hope that Palmer and Larson identify the missing but as-yet

unidentified normatively relevant property that distinguishes ecosystem functions of

value from worthless ones.

This hope is quickly quashed by Palmer and Larson’s first claim about ecosystem

services, which emerges as a non sequitur. As premise, they observe (p. 652) that

whitebark pines ‘‘form… significant functional relationships’’ [italics added]. This,

we have already observed, is an indisputable, universally true biological fact about

all organisms, which by itself has no normative implications whatever. Yet on the

basis of this single, normatively empty premise, they surmise (p. 652), ‘‘In short,

relocated whitebark pine may provide important ecosystem services into the

21 See, for example, Simberloff (2013, p. 66).


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future.’’ This normative claim—about benefits to people—cannot possibly mate-

rialize from the normative vacuum of ecosystem functions.

Only in their essay’s final section do Palmer and Larson characterize the service-

rendering potential of translocated whitebark pines.22 There they observe (p. 657),

‘‘whitebark pines… could produce ecosystem services such as retaining soil

moisture, modifying soil temperatures, slowing the progression of snowmelt, and

helping to moderate flooding at lower elevations.’’ But services such as these are

indifferent to the kind of plant that provides them.23 Demand for them could be at

least as well satisfied by, for example, snow gum (Eucalyptus pauciflora),24which

trumps the whitebark pine in its invulnerability to whitebark’s rust and beetle

nemeses. In fact, it is likely that many cold-tolerant plants are superior to whitebark

pine in having either greater service capacity or lower installation and maintenance

costs. In evaluating service providers, what counts are only the quality of the

services and the cost of providing them; this accounting gives the whitebark little

claim for consideration.25

Biodiversity Options

In light of the concerted effort to link biodiversity to ecosystem services (see

preceding note), it is not unexpected that Palmer and Larson turn from their initial

mention of ecosystem services to the claim (p. 652) that ‘‘[the whitebark pine’s]

continued existence prevents the loss of an increment of biological diversity, thus

retaining biodiversity options for the future’’ [italics added]. Insofar as biodiversity

is here characterized by a global species count, we can all agree with the non-

normative fact that the loss of one species decrements that count.

However, we should focus on the more interesting normative claim made by

Palmer and Larson—that decrementing biodiversity is bad because it loses some

‘‘biodiversity option for the future.’’ The authors do not specify what they mean by

‘‘biodiversity option.’’ However, it is commonly claimed that biodiversity is good

because of its option value (Maier 2012, §6.9). These claims appear to have in mind

one of two possible meanings of ‘‘option value’’ for biodiversity. In informal usage,

‘‘option value’’ is commonly understood to mean ‘‘potentially useful without regard

to whether, why, or how, it will later serve some use.’’ This meaning makes option

22 One might hope that this discussion would fill the lacuna left in Larson and Palmer (2013, pp. 17–18)

where these authors also tout the potential for translocations to bolster ecosystem services, but offer no

substantive reason to support this claim.23 See Maier (2012, pp. 173–174) for more discussion of the indifference of services to particular

service-providers.24 Eucalyptus pauciflora has even earned the imprimatur of the Royal Horticultural Society, with its

Award of Garden Merit for one subspecies.25 It is worth observing that the proposition of ‘‘conserving’’ or bolstering ecosystem properties that

benefit people differs substantially and substantively from ‘‘conserving biodiversity’’—particularly, the

number and identity of species in ecosystems (Maier 2012; Maris 2014; Schroter et al. 2014). This

observation has led to an enormous research program that has spent decades attempting to show that

biodiversity per se is the basis of some functional properties (Tilman et al. 2014). Serious questions about

the validity of this research remain. But even if doubts about the research were allayed, the normative

relevance of these ‘‘functions’’ would remain in doubt.


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value normatively pointless because it applies, not just to biodiversity, but also to

almost everything else. Indeed, it is difficult to imagine anything in the world—even

very bad things—that does not have this kind of value.

On the other hand, neoclassical economics assigns to ‘‘option value’’ a different

and normatively more useful meaning, which incorporates more restrictive criteria.

Economics defines option value as the premium—over and above the expected net

benefit, which benefit is over and above the thing’s cost—that people are willing to

pay, up front, merely to retain the option of consuming it later rather than

immediately. This, despite the fact that the thing’s immediate use, sacrifice, or

‘‘consumption’’ might be quite valuable; that there might be some great cost

involved in keeping it around in addition to the cost of foregoing its immediate

consumption; and despite the risk that demand for it might vanish. These are

extremely stringent conditions that almost nothing meets. It is doubtful that

whitebark pine meets them; Palmer and Larson say nothing to dispel this doubt.26

Calculus of Benefits and Harms to Sentient Creatures

While whitebark pines are not sentient, sentient creatures would be either involved

in, or affected by, AM for that tree. So from the normative quagmires of ecosystem

functions, ecosystem services, and biodiversity options, Palmer and Larson proceed

to a classical utilitarian calculus of benefits and harms to these creatures.

They admit (p. 654), ‘‘the relocation of whitebarks will not help those animals in

areas where whitebark forests are currently dying or in decline.’’ For a more sober

assessment, consider first Clark’s Nutcrackers, which sustain themselves on pine

nuts of whitebarks but also other pines, and which conservationists would

translocate to a newly planted whitebark pine forest in order to keep it reseeded.

One might justifiably say the ‘‘left behind’’ Clark’s Nutcrackers would be harmed,

for the conservation plan does nothing to ensure their continued food supply in

former whitebark territory. Possibly harmed, too, would be the ‘‘brought along’’

birds—perhaps traumatized by their capture and disoriented by their release in an

alien, novel whitebark pine forest.

Against these harms to Clark’s Nutcrackers, Palmer and Larson reprise their

questionable normative logic for ecosystem functions to pose the compensatory

benefit of the whitebark’s pine nuts. While not identifying the species that might

benefit in a target locale for whitebark pine’s AM, they speculate (p. 654), ‘‘the

whitebark pine is likely to provide a new nutritious food source—thus performing a

useful ecosystem function.’’ This suggestion has little credibility—either normative

or biological. While some creatures might benefit from the sudden increase in mast,

those who do (for example, squirrels) might proliferate and push out others who do

not. We have no basis for believing that these creatures would not be harmed as

much as the beneficiaries are benefited.

The credibility of Palmer and Larson’s sanguine view of the functional properties

that might supervene on mass plantings of whitebarks hinges on selectively focusing

26 Maier (2012, §6.9) details how the related claim that biodiversity more generally has option value (in

the economic sense) unravels.


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on a single implication of a new supply of pine nuts. This focus nourishes the

impression that mass importation of biota would change little else. But Palmer and

Larson offer no scientific grounds for stripping the scientific context of other, not

unlikely, transformations—for example, irruption or collapse of some populations,

or disruption of soil from planting.

We defer further discussion of this questionable biology to the ‘‘Biological

Deficiencies’’ section, but it is important to note here a striking normative feature of

Palmer and Larson’s cross-species utilitarian reckoning: It serves as a basis for taking

the side of some species over another based on differential harms that may be inflicted

and benefits that may be conferred. In fact, one can imagine this calculus proposed as

the basis for answering the neglected question (discussed in the ‘‘Missing and Hazy

Moral and Scientific Context’’ section) of which cadre of organisms should be hauled

aboard AM’s life raft. In Animal ethics in context, Palmer (2010) herself brings

attention to how morally problematic this is by reference to what she calls ‘‘The

Laissez-faire Intuition’’. According to this plausible intuition, or Palmer’s refinement

of it (‘‘No-contact LFI’’), which she broadly endorses, no compelling warrant exists

for ‘‘taking sides’’ for or against animals that make their own way ‘‘beyond human

contact’’ (Palmer’s qualifying phrase). For example, she (2010, p. 159) states, ‘‘we

have no duties to pull [wildebeest] from crocodile’s jaws’’ when they cross the Mara

River. It is similarly plausible to think that there is little warrant for championing the

cause of one organism when the actions involved will likely affect the prospects of

others in uncertain ways—including when they suddenly find themselves amidst

whitebark pines.

It is also instructive to ask: why are pine nuts needed in the target locale? One

answer might be that the need arises from relocated Clark’s Nutcrackers—for there

is no evidence that current residents of currently whitebark-free territory suffer

without them. Another possible response is to deny the normative relevance of this

question about need. On this latter view, the relevant question is one of ecosystem

‘‘improvement’’: a habitat with pine nuts supplementing the diets of animals is

simply better than one without them. We shall set aside the problematic implication

of this response, which effectively declares open season for engineering projects

that ‘‘improve’’ ecosystems according to some ecosystem engineer’s idea of desired

characteristics.27 It lacks credibility even on its own terms: if the goal is to

‘‘improve’’ ecosystems by affording pine nuts to its residents, then as we previously

observed, Pinus albicaulis is an inferior planting choice to Himalayan pine nut

(Pinus gerardiana). Their fruits (unlike whitebark’s) are delectable to people among

other animals and command a premium price. That means that Himalayan pine nut

trees, unlike whitebark pine nut trees, would be uniquely qualified to provide this

ecosystem service to people.

Of course, all discussion of possible harms and benefits to assorted sentient

animals in whitebark plantations or other engineered ecosystems is highly

speculative. Speculation cannot legitimately underwrite any particular conclusion

27 This is essentially the credo of novel ecosystem engineering, which we touch on just below in the main

text. The credo admits many rationales, including many that have little or nothing to do with any

commonsense notion of ‘‘conserving nature,’’ for engineering re-arrangements of ecosystems.


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about the balance of these benefits and harms. On the other hand, probable harms to

the most visible creatures appear to be preeminent in a utilitarian assessment of

whitebark pine forests that are meanwhile abandoned and not replanted while new

ones are created.

Novel Ecosystems

Palmer and Larson offer ‘‘A Concluding Argument’’ that does little to salvage their

case for AM of whitebark pine. There they embrace (p. 658) a recent movement in

conservation biology that endorses creating ‘‘novel ecosystems’’ (Murcia et al.

2014; Hobbs et al. 2014). This term alludes to the license granted to ecosystem

engineers for constructing entirely new ecosystems or substantially re-arranging

existing ones. Grounding for this license resides in a single argument. Among

several variants, the simplest and most common has a single premise:

P: People are causally responsible for changing many ecosystems on the planet—

saliently for AM, by contributing to changes in the climate.

C: Therefore, people ought to create, rearrange, and manage ecosystems to have

properties that they desire—for example, properties that render desired

services.

The premise P is a non-normative fact, with which we should all agree. The

conclusion C is a substantive normative proposition—the guiding principle of novel

ecosystem-style conservation. For this argument to succeed, the normative

relevance of P to C must be shown. Advocates of novel ecosystem engineering

evidence little awareness of this requirement, let alone inclination to meet it. So we

must do our best to answer on their behalf.

The most obvious answer is: the value of ecosystems or nature generally should

be principally understood on the model of private property, which its (human)

owners may deploy as they please. But because the world’s extraction industry

operates on this principle, it is doubtfully fit for guiding nature’s conservation.

Another candidate answer emphasizes services that, it is supposed, ecosystems may

be engineered to provide. That answer, as we previously explained, is a non-starter.

One can imagine other answers, none more plausible than these.28

Narratives and Reparations

Palmer and Larson offer two more, interrelated suggestions for thinking that moving

whitebark pine is good, or at least not so bad. It is not so bad, according to them (pp.

657–658), because we can construct good narratives or stories about the pine ‘‘as a

new member of a novel ecosystem with some potentially useful functions’’ rather

than as ‘‘the intrusion of an alien.’’ This indeed would be a good story. But a good

story does not make what the story recounts good, as good stories about slavery

show.

28 Maier (2016) more fully discusses the single-premise version of the novel ecosystem licensing

argument and its variants.


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Finally, Palmer and Larson, following Hale et al. (2013),29 suggest (p. 658),

‘‘Those who argue that species have moral status might deepen these narratives in

terms of ‘restitution’ to species, such as the whitebark pine, that have been forced

out of other locations by human activities’’ [italics added]. As stated, this suggestion

appears to reverse Palmer’s earlier assessment (2012, p. 207): ‘‘As with non-sentient

living organisms, … it is difficult to find a good argument that species can be

wrongfully harmed, and thus they cannot be owed reparation.’’ But inconsistency

does not entail incorrectness, so it is useful to observe two serious confusions that

undermine Palmer and Larson’s suggestion for reparation to the species Pinus

albicaulis.

First, Palmer and Larson immediately afterwards state, ‘‘it’s difficult, ethically, to

make an argument that restitution or reparation can be directly owed to non-humans

(with the possible exception of sentient animals).’’ This statement may be

interpreted to change the subject from restitution directed at species to the different

topic of restitution to individuals. On the latter topic, Palmer (2010, Ch. 6)

acknowledges that the notion of some backward-looking obligation to ‘‘make good’’

a harm is fraught with multiple difficulties even when people are harmed and when

they or their descendants are available to help determine what sorts of actions would

constitute reparation. What is problematic with respect to making restitution to

people even in best-case scenarios is unimaginable for individual trees. Why, for

example, shouldn’t we think that abandoning many whitebarks on long-occupied

turf and using many others to create tree plantations in alien environments

constitutes, not restitution, but rather disregard for the ‘‘moral status’’ of these trees?

This last question exposes the second confusion. The fact that some thing—either

a species or an individual organism—has ‘‘moral status’’ implies little specific about

how moral agents ought to act with respect to them. For example, it entails nothing

about whether reparations make moral sense with respect to the thing, and if they

do, what they sensibly might be thought to consist of. Rather, the possession of

‘‘moral status’’ entails only that its possessor, which matters for its own sake, must

somehow be taken under moral consideration; the ‘‘how’’ is left to determination by

further normatively relevant facts about it.

A variant of this second kind of confusion also dogs a final attempt to salvage the

case for reparation by subsuming this complex of substantive issues within the word

‘‘symbolic.’’ A ‘‘symbolic reparation,’’ they (p. 658) and Palmer (2012, p. 207)

suggest, may serve as a symbolic expression of ‘‘regret and sorrow over past

environmental destruction.’’ But the suggestion that some people feel that

translocating organisms symbolically expresses their regret is a normatively

29 Hale et al. (2013, p. 68) present an ‘‘ ’Argument from Reparation,’ which, suggests that our obligations

to assist in adaptation stem from a moral obligation to right prior wrongs.’’ These obligations, they say,

‘‘rest on a prior failure to justify one’s actions.’’ However they, like Palmer and Larson, neglect to discuss

a number of critical elements, which a credible reparation argument must include. The most basic are:

what, exactly the ‘‘prior wrongs’’ consist of, what or whom (if any particular things) is wronged, and what

reasons we have to consider some particular ‘‘assisted adaptation’’ measure to constitute the morally

required reparation actions. At one point, Hale et al. hint that nature is the thing that has been wronged by

suggesting that restituting actions be taken ‘‘on behalf of nature.’’ But this helps little, absent some

plausible account of what it means to wrong nature and how, exactly, adaptive interventions have moral

significance as acts of restitution.


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unimportant sociological fact. It has little relevance to the normative question of

whether or not this practice ought to be regarded as a symbol of regret.

Biological Deficiencies

We have already touched on several elements of questionable biology in Palmer and

Larson’s discussion. We now return to this matter, which like much of their

normative argument, suffers as a consequence of cutting away significant context.

For example, Palmer and Larson repeatedly (pp. 641, 644, 651–652) highlight the

status of whitebark pine as a keystone species and a foundation species. This, they

say, significantly enhances the well-being of many species with which it interacts

directly or indirectly in its historic range. But they do not consider the implications

of this characterization when assessing the likelihood that whitebark pine will (p.

651) ‘‘threaten any ecosystems’’ in its new homes because, according to them, it

‘‘lacks invasive potential.’’ If it exerts outsize influence as a keystone and

foundation species in its existing range, it is difficult to be confident that its

interactions with species in its new range will not be so substantial as to ‘‘threaten’’

previously existing ecosystems there, or at least certain species within them. Were

the tree’s influence to qualify it as a keystone or foundation species in its

transplanted locale, then by the lights of many (Simberloff 1991), it would at that

point ipso facto be invasive. And if its introduction wrought changes in the

characteristic properties that identify an ecosystem, then one would say that the

‘‘threat’’ to the original ecosystem actually wrought its destruction.

We have already observed that whatever force Palmer and Larson’s discussion of

possible functional benefits of whitebark’s translocation may have largely derives

from selective focus on the tree’s provision of mast to already-resident creatures.

This blinkered view excludes a body of scientific evidence that points to a

substantial likelihood for a quite different outcome of a mass importation of biota.

For example, soil disturbances, such as those expected from mass plantings of trees,

are associated with deplored plant invasions, such as those that Davis et al. (2000)

recount to support their general theory of invasibility. Its likelihood is heightened in

the case of AM for whitebark pine if the target locale resembles the tree’s native

habitat in having impoverished soils and generally marginal conditions. The science

also suggests there is no small likelihood that some populations of existing residents

may irrupt or collapse.

The corpus of invasion biology chronicles indirect, unanticipated, and sometimes

regretted effects of imported organisms initially judged to be innocuous or even

beneficial. For example, some organism, benign to whitebark pines, might hitchhike

on them but adversely affect some resident in the target ecosystem.30 If the new

plantings resist blister rust, that fungus might accompany whitebarks and find new

hosts in their new home. Highly relevant to this possibility is, for example,

Karlman’s work (2001), which points to the danger of introducing fungal pathogens

30 For a raft of other ways in which an organism’s introduction may trigger prediction-defying effects,

see Simberloff (2013, pp. 85–96).


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to Scots pine (Pinus sylvestris) forests of Sweden by virtue of establishing

plantations of Canadian lodgepole pine (Pinus contorta).

Other sources of scientific skepticism center on omitted context regarding Clark’s

Nutcrackers, which an AM project would ‘‘plant’’ alongside whitebark pines. Other

animals—for example, the cane toad in Australia, small Indian mongoose in Croatia

and elsewhere, and rosy wolf snail on Pacific islands31—imported on account of

their well-documented appetite for some particular organism, defied expectations by

failing to control the target species and instead devastating populations of one or

more other species. Should Clark’s Nutcracker find some food in its new location

more to its liking than whitebark pine nuts, it may not serve its ‘‘ecosystem

function’’ of sustaining whitebark pine by planting its seeds. The birds, too, might

bring along their own set of pathogens; these could adversely affect resident birds.

Finally, Clark’s Nutcracker is supposed to be necessary to launch a fledgling

whitebark forest successfully. But justifying this scheme also requires so-far

unexplained grounds for thinking that the chain of dependencies stops there. In fact,

there are grounds to think that Clark’s Nutcracker is not the only organism that must

be brought along: Cripps and Antibus (2011) and Cripps and Grimme (2011) present

evidence of whitebark pine’s complex and critical dependence on certain

ectomycorrhizal fungi.

Finally, Palmer and Larson also do not address important questions regarding

survival prospects for a newly created whitebark forest. A new forest is not

guaranteed to persist.32 Among possible causes of demise for a mass planting of

trees in a new location is vulnerability to previously unencountered pathogens. For

example, Chilean plantations of Monterey pine (Pinus radiata) are threatened by a

recently emergent needle blight (Phytophthora pinifolia) (Duran et al. 2008). The

origin of this oomycete is not yet known. It might also have been introduced; or

because oomycetes readily hybridize, this one might have emerged as a hybrid of

some innocuous resident with an also-innocuous introduced species. Apparently, the

mass planting of Monterey pine created specific host conditions that abetted the

pathogen’s emergence and spread.33 No special quality of whitebark pine rules out a

similar fate for mass plantings of that tree.

Conclusion

In the vast and growing commentary on AM, in which even ‘‘skeptics’’ hold it up as

an ecosystem engineering technology that may ‘‘help save the planet’s biodiver-

sity,’’ we find no credible arguments justifying this view. A common theme in this

31 While these animals are all predators and Clark’s Nutcracker is not, the general principle remains.

Predation is but one of multiple means of placing pressure on the populations of other creatures—as

illustrated by the barred owl’s displacement of spotted owl populations in the U.S. Pacific northwest.32 Recall Dodd and Seigel’s (1991) report of less than a 20 % ‘‘success’’ rate for amphibian relocations.33 Maritime pine (P. pinaster) and Douglas fir (Pseudotsuga menziessii) growing in close proximity to

infected Monterey pines appear unaffected by the previously unknown oomycete (Duran et al. 2008,

p. 726).


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failure is selective omission of important moral questions and scientific facts. Some

‘‘pragmatists’’ even explicitly argue for this exclusion.

Problems in the normative discussion of AM start with incoherence in framing

this technology in terms of ‘‘saving biodiversity.’’ Big moral questions are ignored,

such as how we morally justify a choice of the tiny set of organisms that AM, even

in the most sanguine projections, could hope to serve. Casting AM as the ‘‘lesser of

two evils’’ to be deployed in ‘‘crisis’’ conditions fosters disinclination to assess these

and other moral questions more carefully. This feeds back into overly sanguine and

normatively and scientifically truncated assessments both of what AM might

credibly be hoped to do, and of why it might be the wrong thing to do.

Ron Sandler surmised that AM could be but rarely justified on the basis of any of

a wide-ranging collection of views about what makes species valuable. In their

effort to argue that whitebark pine is one of those rare cases and that there may be

other, similar ones, Palmer and Larson accomplish the contrary. If we can expect no

better arguments than theirs, we should believe that AM is not just rarely justified,

but that it cannot be justified.

Palmer and Larson’s arguments reflect the broader debate by their setting in a

skeletal normative and scientific context. Beyond that are mistaken normative

principles—that moral truths may be established by survey; that the bare fact that an

organism ‘‘has a function’’ in an ecosystem makes its presence good; that a good

story about a thing or state of affairs makes that thing or state of affairs good.

Alongside these mistaken principles are incorrect or implausible normative claims

and assumptions—that whitebark pines have option value; that an inter-species

utilitarian calculus of suffering inflicted on sentient creatures can justify harming

one species to benefit others. The appeal to ecosystem services, understood with its

central meaning of ‘‘functions benefiting people,’’ merits special mention. Even if

an organism’s capacity to benefit people were a morally respectable test for judging

whether it merits a place on the planet, this consideration would almost certainly

condemn rather than spare most organisms, including whitebark pine, whose

service-rendering capabilities are probably inferior to other trees’.

Like most AM proponents, Palmer and Larson neglect science that casts doubt on

their views. They argue for assisted migration principally as means to preserve the

species whitebark pine, yet gloss over alternative means, despite advantages some

may have. They also overlook scientific literature on the surprising turns sometimes

consequent on actions that disturb soil and that may inadvertently import pathogens

of other species or even engender new pathogens that may compromise whitebark’s

prospects. It is noteworthy that this omission of the possibility of a disproportion-

ately large effect of the whitebark on its new environs is selective in a way does not

cohere with Palmer and Larson’s emphatic characterization of whitebark as a

keystone and foundation species in its current environs.

These thoroughgoing and systematic failures of reasoning about AM should

prompt reflection on their causes, which may be rooted in the social and institutional

context of AM’s discussion (Dodd and Seigel 1991, pp. 342–344; Dodd 2005,

p. 269). That is a topic for another essay.


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