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For exceptions, permission may be sought for such use through Elsevier's permissions site at: http://www.elsevier.com/locate/permissionusematerial From Sarkar Sahotra, Habitat Reconstruction: Moving beyond Historical Fidelity In: Dov M. Gabbay, Paul Thagard and John Woods, editors, Handbook of The Philosophy of Science: Philosophy of Ecology. San Diego: North Holland, 2011, pp. 327-361. ISBN: 978-0-444-51673-2 © Copyright 2011 Elsevier B. V. North Holland. Author's personal copy HABITAT RECONSTRUCTION: MOVING BEYOND HISTORICAL FIDELITY Sahotra Sarkar 1 INTRODUCTION Today, only the very fortunate live and work in landscapes that do not bear the indeliblemarkofcontinuinghighlyintrusiveanthropogenic transformation. Biota continuetobereplacedbyhumanartefactsortobeconfinedtosmallsub-optimal patches. Ecologicalandphysicalprocessesoftenmanifestthemselvesonlyinforms dominated by the effects of human action. Besides the obvious harm to biota, the consequences of how land- and seascapes have been treated by human activities have typically included the depletion of natural resources, the deterioration of air and water quality, and our increased vulnerability to extreme weather events. We continue to alter climate in ways that may jeopardize the well-being of future generations. All this is common knowledge, and often presented with much more rhetorical flourish than in the paragraph above. The standard twentieth-century response to these problems has been calls for increased reservation, setting aside land- and seascapes to preserve natural values. On land, at least superficially (that is, on paper if not in practice), this strategy has been quite successful during the last 25 years (1980–2005). By 2005, 17.1 million km2 or 11.5% of Earth’s terrestrial surfacewassupposedtobeundersomeformofprotection.1 Thisisclosetothe12% target, then considered visionary, that the Brundtland Commission recommended in 1987.2 So far, the seas have not fared as well: only 2.35 million km2 or 0.65% of the sea surface are under the aegis of a conservation plan.3 However, efforts to designate more marine reserves continue.4 Nevertheless, if the long-term retention and enhancement of natural values is among our aspirations, reservation is not enough for at least six reasons. 1. The scale of the human impact on nature over the last few centuries has beensoextremethatnotenoughareaswithflourishingnaturalvaluesremain. 1Naughton-Trevesetal.[2005]. Mostestimatesaresimilarthoughtheexactnumberdepends onthecriteriausedtodefineprotectedareas. 2WCED[1987]. 3Woodet al.[1987]. 4See,forexample,[Wood,2007]foraglobalanalysisaimedatprotecting1,038fishandmarine mammalspecies. HandbookofthePhilosophyofScience. Volume11: PhilosophyofEcology. Volume editors: Kevin deLaplante,Bryson Brown and Kent A. Peacock. General editors: Dov M.Gabbay,PaulThagardandJohnWoods. (cid:13)c 2011ElsevierBV.Allrightsreserved. Author's personal copy 328 SahotraSarkar Evenbarelyintactecosystems(thosewithonlyamajorityoftheirtraditional biological components remaining viable) are becoming increasingly rare. 2. Ifgenuineprotectionfromhumanabuseistherelevantcriterion,thenumbers in the last paragraph are inflated. Some of these “protected” areas allow a wide range of human activities, including resource extraction so long as it is touted to be sustainable.5 3. Many of these protected areas are “paper parks,” designated as such by some legal authority, but not implemented on the ground due to the lack or resources, political will, or both. 4. If biodiversity is one of the natural values that the areas are supposed to protect, almost 80% of the protected areas are not viable because they are lessthan10,000hectaresinsize6 andthusnotlikelytoensurethelong-term persistence of all their biota if they are isolated from other natural habitats. 5. Moreover, even if designation of new protected areas continues at the rela- tively high rate of the 1980–2005 period, which is unlikely, most new pro- tected areas will continue to be small. Further transformation of the land will increasingly isolate these areas. 6. Perhaps most importantly, to maintain these individual protected areas in viable states (that is, to prevent habitat deterioration within them) will require active management: mere reservation will not be enough. There is no such thing as benign neglect any more: the human impact on Earth is now far too extensive and much too harsh. Forreasonssuchasthese,itisbynowwidelyrecognizedthatwemustmovebeyond reservation and actively manage habitats to enhance the natural values embod- ied in them.7 Typically such efforts are viewed as ecological restoration. The aim of this paper is to argue that restoration as now understood by those who advocate it most systematically—for instance, the Society for Ecological Restora- tion International—is far too restrictive in the scope of its aims. The standard theoretical characterization of ecological restoration—though not always how it is practiced—is that it has two goals: ecological integrity and historical fidelity.8 Botharenormativegoalsthataresupposedtoguidepolicy. Ecologicalintegrityis 5Naughton-Treveset al.[2005]. 6ThisfigurereferstoanyoftheTypesI–VIprotectedareasoftheclassificationduetoIUCN (theWorldConservationUnion,formerlyknownastheInternationalUnionfortheConservation ofNatureandNaturalResources). Ifonlystrictlyprotectedareasareconsideredthepercentage wouldlikelybeevenhighersincethesetypicallytendtobesmallinsize. 7Hobbs&Norton[1996]. 8See [Higgs, 2003, p. 95]. Hobbs and Norton [1996] also emphasized how restoration efforts (broadlyconstrued,thatis,whatisbeingcalledhabitatreconstructionhere)shouldbeguidedby adynamiccriterionandareferencestatecriterion. Muchearlier,BradshawandChadwick[1980] had also implicitly embraced a dynamic criterion and a reference criterion (see the discussion belowinSection3). Author's personal copy HabitatReconstruction: MovingbeyondHistoricalFidelity 329 what will be called here a dynamic criterion, that is, one specifying how a system should change over time.9 Very roughly, it is a measure of how intact a system is inthewayitbehaves(seeSection4formoredetail). Incontrast,historical fidelity is what will be called a reference state criterion, specifying, again roughly, what a system looks like as captured by its state variables (see Section 5). We shall see, below, that ecological integrity may be questionable as a goal, or at least, as the only dynamic (or functional) goal of natural value enhancement programs. However, the real trouble with restoration is its insistence on historical fidelity as the (reference state) goal of such efforts. This paper will argue that thereisrarelyanyjustifiablenormativegroundfordeifyinghistoricalfidelity,even withoutworryingaboutwhetheritisachievableinpractice,orwhetheritisworth the resources it would consume.10 Rather, habitat reconstruction should embrace the enhancement of a wide array of natural values through active intervention. Restoration,asthespecificgoalofhabitatmanagement,isadevelopmentoffairly recent vintage. The other natural values that are being advocated here formed part of many past habitat management efforts that have been called by a vari- ety of names, especially before 1980—for instance, reclamation,11 regeneration,12 rehabilitation,13 and revegetation,14 besides, of course, reconstruction,15 which is what this paper endorses. To ground the later theoretical discussion in a tangible context, Section 2 presents an example in some detail: this is the case of the Balcones Canyonlands National Wildlife Refuge in central Texas, some 70 km west of Austin, Texas. Section 3 will note how the enhancement of degraded habitats, that is, their man- agementfortheenhancementofnaturalvalues,hereaftercalledhabitatreconstruc- tion, came to be conceptualized as restoration in the 1980s and 1990s. This is a complicated story, one that historians and philosophers have barely begun to ex- plore,16 and only a very few themes can be tracked here. Section 4 will note some problems with ecological integrity as the dynamic goal of reconstruction efforts but will then set that problem aside for more detailed exploration on some other 9This may initially appear strange because most definitions of ecological integrity explicitly refer to the state of an ecosystem (what species are in it, etc.) rather than how it is chang- ing. However, when we probe deeper, the concern is typically over processes and, thus, about dynamics. 10Although this paper intends to give a fairly broad philosophical interpretation of what is calledecologicalrestoration(anddelvesintosomeofitshistory),itdoesnotaddressfoundational issues about the science of restoration ecology. For an entry into that philosophical discussion, seeCallicott[2002]andhissimilarcontributiontothisvolume. Withinrestorationecology,Higgs andNortonprovideaninfluentialpioneeringdiscussion. 11See, for instance, [Kohnke, 1950; Costigan et al., 1981; Schaller and Sutton, 1978]. Higgs [2003,p.99]tracesthistermbacktothelate1800s. IntheUnitedStates,itwaslegallydefined in1977bytheSurfaceMineControlandReclamationAct[Jacksonet al.,1995]. 12See,forinstance,[Lewis,1976]. 13See,forinstance,[US-NAS,1974;GudinandSyratt,1975;DibbleandBartha,1979]. 14See,forinstance,[Gemmell,1973;1974;Johnsonet al.,1976]. 15See,forinstance,[Hall,1941;Bradshaw,1983]. 16See,inparticular,[Higgs,2003;Hall,2005]. Asignificantpartofthispaperisaresponseto [Higgs,2003]whichisapowerfulstatementofadifferentperspective. Author's personal copy 330 SahotraSarkar occasion. Section5willarguethecaseagainstthepursuitofhistoricalfidelityasa necessary normative goal of restoration. Section 6 will then explore other natural values that can also credibly (that is, with normative justification) serve as goals of habitat reconstruction. Section 7 will finally state the reconstructionist agenda insomedetail. Section8willdrawsomeconclusions. Themostsalientonewillbe noted here to prevent misunderstanding of the aims of this paper: much—though notall—ofthepractice,ratherthanthetheory,ofwhatiscalledecologicalrestora- tion remains untouched by this critique. That practice often does not adhere to the definition of restoration advocated by theorists—and that is how it should be. In fact, the reconstructionist agenda offers normative support for many of these broader practices. The analysis presented here should be viewed as an attempt to provide better foundations for those practices. Throughout, this paper draws heavily on examples from Texas because habitat reconstruction is typically best begun at home no matter where you happen to live. 2 THE BALCONES CANYONLANDS The Hill Country of Texas is the eroded southeastern fringe of the semi-arid Ed- wards Plateau which is a large (> 70,000 km2) oblong region of central Texas defined by its bedrock, thick flat layers of hard early Cretaceous limestone, some- times 3,000 m deep. Its northern and southwestern limits are not geologically well-defined.17 The Hill Country forms its southeastern border and gets its name from its many hills and valleys. Its northwest border is also not sharply defined, blending into the rest of the Edwards Plateau, but the southeast consists of the Balcones Escarpment, a now inactive fault line that resulted from a major up- heaval in the Tertiary era. This is not a high cliff in spite of its name; rather, it is a band of canyon country also known as the Balcones Canyonlands. It marks a transition from the plateau to the plains of the south and east. Around the city of Austin, in the north-eastern Balcones Canyonlands, nat- ural habitat management is focused on two endangered migratory bird species, the Goldencheeked Warbler (Dendroica chrysoparia) and the Black-capped Vireo (Vireo atricapillus), which nest there during the summer.18 Both winter in Mesoamerica and are endangered primarily because of the destruction of their nesting habitat in the United States. These are not the only species of conserva- tion concern in the region. The limestone geology of the Edwards Plateau has led tothedevelopmentofanintricatenetworkofundergroundcaves,fissures,andsink- holes. Erosion has led to the isolation of different underground karst cave systems from each other and resulted in the evolution of a suite of endemic cave inverte- brates, several of which are endangered while the status of many others remain 17Fowler [2005]; Sarkar [forthcoming]. Most of the information about the Balcones Canyon- landsNationalWildlifeRefugeusedinthispaperisfromthelattersource. 18Beatley et al. [1995]. During the discussion of the Balcones Canyonlands and other US examples,throughoutthispaper,theterms,“endangered,”“threatened,”etc.,arebeingusedin accordancewiththeUSEndangeredSpeciesAct(1973). Author's personal copy HabitatReconstruction: MovingbeyondHistoricalFidelity 331 to be properly investigated. These endangered troglobites include three insects, the Tooth Cave ground beetle (Rhadine persephone), the Kretschmarr Cave mold beetle (Texamaurops reddelli), and the Coffin Cave mold beetle (Batrisodes tex- anus), and four arachnids, the Bone Cave harvestman (Texella reyesi), the Bee Creek Cave harvestman (Texella reddelli), the Tooth Cave spider (Neoleptoneta myopica), and the Tooth Cave pseudoscorpion (Tartarocreagris texana). Ultimately,whatpushedallthesespeciestothebrinkofextinctioninthe1980s was the rapid urban expansion in and around Austin, and the concomitant trans- formation of natural habitat into residential and industrial developments. In re- sponse,duringtheearly1990s,theCityofAustin,TravisCounty(whichsurrounds Austin), regional environmental organizations, and developers embarked on an ambitious attempt to formulate a habitat conservation plan (HCP) for ten at- risk species so as to permit continued development without violating the (United States) Endangered Species Act (ESA). A tortuous planning process19 resulted in the creation of two protected area systems: the Balcones Canyonlands National Wildlife Refuge owned and administered by the United States Fish and Wildlife Service (USFWS) and the Balcones Canyonlands Preserve System belonging to the City of Austin and Travis County. Each system is administered separately and the focus of this paper will be on the former. The Refuge acquisition area (that is, the geographical region within which US- FWScanacquireland)isabout80,000acres,ofwhich31,000acresareplannedfor outrightacquisitionandafurther10,000acresareenvisionedtobemanagedunder conservation easements.20 Between 1992, when the Refuge was first established andnow,about20,000acreshavebeenacquiredandanother2,000acreshavebeen putunderconservationeasements. Exceptforbirdandsurfacevegetationsurveys, the acquired areas have not been fully explored to date. So far, four aquatic and seven terrestrial troglobites have been found in the caves in the Refuge though none is yet listed as endangered or threatened. Consequently, management efforts arefocusedonthetwoendangeredbirdspecies(theVireoandtheWarbler). How- ever, at least one karst troglobite, the ground beetle, Rhadine russelli, is endemic to the Post Oak Ridge which falls within the Refuge acquisition area. Four other species, aflatworm possibly of the genusSphalloplana, aspiderof the genusCicu- rina, a centipede of the genus Theatops, and a millipede of the genus Speodesmus, areallbelievedtobeunstudiedspeciesandprobablyalsoendemictothePostOak area. Finally four of the other species, an asselid isopod, Caecidotea reddelli, an amphipod,Stygobromus bifurcatus,apseudoscorpionofthegenusTartarocreagris, andamoldbeetle,Batrisodes reyesi,arerecognizedasspeciesofconcerninTexas. Since the cave habitats of these species are within the Refuge, they automatically have some legal protection even without active management. SeveralrareplantsarealsopresentintheRefuge. Themostinterestingofthese is Texabama croton, Croton alabamensis var. texensis, which is locally abundant 19SeeSarkar[forthcoming]. 20USFWS[2001]. WeswitchtotheBritishsystemofmeasurementindealingwiththeRefuge becausealldocumentationconnectedwithitusesthissystem. Author's personal copy 332 SahotraSarkar in many canyons in the Refuge. Besides the Refuge population, which spills off into adjacent private lands, there are two other populations in Texas, one about 80kmnorthoftheRefugeatFortHood,andoneabout5kmsouth,atPaceBend Park. These populations form a variety of their own (and probably should have the status of a subspecies) and the only other known populations are found in Alabama (C. alabamensis var. alabamensis) some 1,000 km away.21 Locally rare plants include the microendemic Sycamore-leaf snowbell, Styrax platanifolius ssp. platanifolius, and the Shooting Star, Dodecatheon meadia. Two other species that probably merit endangered status but are yet to be listed are found in the neigh- borhoodthough,sofar,havenotbeenrecordedwithintheacquisitionarea. These are the Canyon mock-orange, Philadelphus ernestii, and the Bracted twistflower, Streptanthus bracteatus. An experimental population of the latter was established within the Refuge in the 1990s but not allowed to persist at the conclusion of the experiment. Most of the Refuge is limestone-dominated terrain. The plant community of the Refuge forms an ecotone with the mixing of species from different ecological communities. Sofar,over600plantspecieshavebeenrecordedintheRefuge. The historical vegetation pattern of the Refuge, as for the rest of Edwards Plateau, remains very poorly known.22 Consequently, no habitat reconstruction effort can seriously claim to be guided by historical antecedent. Today, most of the Refuge is dominated by a variety of juniper-oak woodlands. Ashe juniper (Juniperus asheii) is ubiquitous as part of such woodlands and as an aggressively spreading shrub in open lands. Its spread must be managed to create sufficient desirable Black-cappedVireohabitat(seebelow). Theoakspresentvarywiththeterrainof the Refuge. Spanish oak (Quercus buckleyi) is mostly found on steep slopes and ravines; plateau live oak (Q. fusiformis) grows best on plateau tops and deep soil in valleys; shin oak (Q. sinuata var. breviloba) is present as thickets on very rocky plateau sites; and post oak (Q. stellata) is present on open savannahs on higher elevations of the Refuge—this region is called Post Oak Ridge. Besides the juniper-oak woodlands, open grasslands are a major feature of the Refuge. Texas is famous for its wildflowers and a large diversity of these are con- spicuousatthebeginningofthespringandfallfloweringseasons. Amajorproblem isthespreadoftheinvasivegrass,KingRanchbluestem,Bothriochloaischaemum, whichhascometodominatemanyoftheopengrasslandsandsavannahs. Manage- ment of K. R. bluestem has proved to be particularly difficult throughout central Texas. Canyon bottoms and narrow valleys along creeks have riparian woodland corridors containing American elm (Ulmus americana) and sycamore (Platanus occidentalis) among many other species. Like the caves, the creeks have not been fully explored and may contain at-risk amphibians such as the Jollyville Plateau Salamander (Eurycea tonkawae) which is a candidate for listing under the ESA. 21See [Ginzbarg, 1992] on designating this population as a variety. Van Ee et al. [2006] raise thepossibilityofupgradingittoasub-species. Ifthathappens,thepopulationwouldfallunder theaegisoftheESAandcouldpotentiallybelistedatleastasthreatened. 22Fowler[2005]. Author's personal copy HabitatReconstruction: MovingbeyondHistoricalFidelity 333 Habitat management in the Refuge is complicated because the two endangered birdshavedifferenthabitatrequirementsandtheirneedsmustbebalanced.23 The Black-capped Vireo prefers to nest in mid-successional shrub oak or other shrub vegetation not dominated by Ashe juniper.24 In sharp contrast to the Vireo, the Golden-cheeked Warbler prefers to nest in climax mixed oak-juniper woodlands with tree heights between 3 and 6 m.25 Refuge staff restore,26 that is, create and maintainsuchhabitatbytheactivemanipulationofvegetationinavarietyofways including prescribed burning. The spread of Ashe juniper requires active control. ThroughouttheRefuge—and,forthatmatter,theentireBalconesCanyonlands— expanding populations of white-tailed deer (Odocoileus virginianus) are a major problem for revegetation programs because of excessive browsing. Deer herd con- trolincludeshuntingbesidesencouragingimprovementofdeerhabitatinadjacent lands in order to decrease pressure on the Refuge. An additional serious prob- lem for the Vireo is nest parasitism by Brown-headed Cowbirds (Molothrus ater). Cowbirds are trapped during the breeding season and removed. Management plans include identification and evaluation of sub-climax habitat for monitoring and active protection.27 White-tailed deer herd management is also required for the Warbler, as is control of Brown-headed Cowbirds though the latter do not present as significant a problem for this species as it does for the Vireo. Oak wilt management has emerged as an important issue in several areas of the Refuge.28 Finally, excessive public use of the Refuge has had to be curtailed in some areas during the breeding season. An important decision for Refuge management is to decide how much habitat should be managed for each endangered bird species, and where these should be located. 3 DEFINING ECOLOGICAL RESTORATION Though there is a long and rich history of antecedents (for instance, in the highly influentialworkofAldoLeopoldinNorthAmerica),29 ecological restoration,aswe distinctivelyunderstandthatpracticetoday,emergedintheearly1970samidstthe variety of reconstructionist practices that were mentioned in Section 1. The idea ofrestorationasthegoalofhabitatmanagementwasarticulatelypromotedbytwo major figures, A. D. Bradshaw in the United Kingdom and John Cairns Jr. in the United States along with many other proponents. A series of conferences during the 1970s highlighted the importance of restoration. For instance, on Friday, 16 April 1971, the (United States) Association of Southeastern Biologists (ASB) 23[USFWS,2001,p.7]. 24Grzybowski[1995]. 25LaddandGass[1999]. 26USFWS[2001,p.38]. 27USFWS[2001,p.37]. 28USFWS[2001,p.37]. 29Fortheearly history, see [Hall, 2005]. Thisbook is an unusually valuable resource because itexploresthehistoryofreconstructioneffortsbeyondthecustomaryNorthAmericancontext. Author's personal copy 334 SahotraSarkar andtheCenterforEnvironmentalStudiesoftheVirginiaPolytechnicInstituteco- sponsoredaSymposiumontheRecoveryandRestorationofDamagedEcosystems at the 32nd Annual Meeting of the ASB at the University of Richmond.30 The conference had taken three years to organize. The program proclaimed: Much attention has been given to the prophets of doom who are be- wailing the fate of the planet, and the terrible things that are happen- ing to the environment. However, little attention has been given to theconstructiveandpositiveapproachestocopingwithenvironmental problems, either through deliberately restoring damaged ecosystems or relieving the pollutional stress sufficiently for them to recover by themselves. This symposium will deal with practical problems and casehistoriesdescribedanddiscussedbypeoplewhohaveworkedwith these real problems and case histories. [Anonymous, 1971] The speakers included Cairns on damaged streams, Ronald D. Hill on mines, Robert R. Curry on forests, and Thomas L. Linton on estuaries.31 Both Hill and Linton explicitly used restoration to describe their programs in what was one of the earliest modern uses of the term in an ecological context. Another conference at the Virginia Polytechnic Institute in March 1975 led to an edited book, Recovery and Restoration of Damaged Ecosystems.32 Across the Atlantic, a North Atlantic Treaty Organization (NATO) conference at Reykjavik, Iceland, in July 1976 produced The Breakdown and Restoration of Ecosystems.33 By 1980, Bradshaw and M. J. Chadwick had produced The Restoration of Land, essentially a textbook waiting for the emergence of an academic discipline.34 A theme that runs throughout these works is that “[l]and [and, presumably, also aquatic habitats] is not a resource which automatically renews itself like rainfall andsunlight... . [T]heprofligatedaysareover. Wehavetobepreparedtorestore exploited land to a condition approaching its original biological potential.”35 In 1981theUniversityofWisconsin—MadisonArboretumbeganpublishingRestora- tion and Management Notes, the first periodical dedicated to the emerging field; in 1999 it changed its name to Ecological Restoration, which remains what it is called today. The Society for Ecological Restoration (SER) was founded in 1988; its journal, Restoration Ecology, began appearing in 1992. Restoration ecology, as the discipline dedicated to ecological restoration, thus emerges as an organized discipline at roughly the same period as conservation biology.36 There was—and, to some extent, there remains—tension between the two fields with conservation biologists fearing that the acceptance of restoration as a goal would diminish sup- 30Anonymous[1971]. 31See[Cairnset al.,1971;Hill,1971;Curry,1971;LintonandCooper,1971]. 32Cairnset al.[1977]. 33HoldgateandWoodman[1978]. 34BradshawandChadwick[1980]. 35BradshawandChadwick[1980,p.2]. 36Forthehistoryofconservationbiology,see[Sarkar,2005]. Thecrucialdatewas1986when theSocietyforConservationBiologyanditsjournal,Conservation Biology,werebothfounded. Author's personal copy HabitatReconstruction: MovingbeyondHistoricalFidelity 335 portforprotectingwhateverrelativelyintactecosystemsthatremained.37 Byand large, during the late 1980s and early 1990s, the two disciplines evolved indepen- dently.38 However, in spite of its increasing popularity, the use of the term, restoration, remainedfluid. InTheBreakdownandRestorationofEcosystems,theeditorsiden- tified restoration with rehabilitation. In their textbook, Bradshaw and Chadwick explicitly chose a broad interpretation: Reclamation is often used where some new use of the land will be involved; rehabilitation is sometimes confined to improvements of a visual nature. Restoration may be used only where land is to be re- turned to its former use and renewal or redemption may be used in a form that enables flexibility in planning its re-use. The term revege- tation is generally confined to situations where the original vegetation has been destroyed and its reappearance in some form is to be encour- aged. In this book restoration is used as blanket term to describe all those activities which seek to upgrade damaged land that has been destroyed and to bring it back into beneficial use, in a form in which the biological potential is restored.39 Notethatthereisnoinsistenceonachievingsimilaritytosomepasthistoricalstate or trajectory even though such a more restricted construal of restoration is noted as a possibility. Eight years later, Cairns produced a similarly general definition: “restoration ecology is the full or partial placement of structural or functional characteristics that have been extinguished or diminished and the substitution of alternative qualities or characteristics than the ones originally present with the provisothattheyhavemoresocial,economic,orecologicvaluethanexistedinthe disturbed or displaced state.”40 Onceagainthereisnoendorsementofhistoricalfidelity. Noristheremuchcon- cern for forging a universally acceptable definition.41 Nevertheless, by 1988, with thefoundingoftheSER,definitionalcontroversiesbegantogetexplicitattention. Between 1988 and 1994 the SER produced three official definitions of ecological restoration.42 It was during these discussions that fidelity to a historical past began to become central to how restoration was conceived: restoration consisted of aiding and abetting a system’s return to that past. In 1992, the Committee on Restoration of Aquatic Ecosystems appointed by the United States National 37Cairns[1988]. 38See, however, [Cairns, 1986; Janzen, 1988] for early attempts to bridge the divide. An influentiallaterattemptis[HobbsandNorton,1996]. 39[BradshawandChadwick,1989,pp.2–3];italicsasintheoriginal. Notehowthisdefinition implicitlyinvokesareferencestatecriterion(upgradingdegradedland)andadynamiccriterion (restorationofbiologicalpotential). 40Cairns[1988,p.3]. 41Hobbs and Norton [1996] even argued for the irrelevance of attempts to define restoration universally. 42Higgs[2003,p.102].
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