Biological Integrity Versus Biological Diversity As Policy

BiologicalIntegrity versus Biological Diversity as Policy Directives Protecting biotic resources

Paul L. Angermeier and James R. Karr

wo phrases-biologicalinteg- advanced on ecological impacts in rity and biological diversity- Resource would these systems (e.g., Allan and Flecker have joined the lexicon of policy 1993, Schindler 1990), and rates of biologists and natural resource man- be most effective if extinction and endangerment for agers during the past two decades. aquatic fauna exceed those for ter- The importance of these phrases is the goal were the restrial fauna. Among North Ameri- demonstrated by their influence on can animals, for example, Master environmental research, regulatory, protection of (1990) reported that 20% of fishes, and policy agendas. The concepts 36% of crayfishes, and 55% of behind the phrases are central to biological integrity mussels were extinct or imperiled, strategies being developed to sus- compared with 7% of mammals and tain global resources (Lubchenco et birds. Similarly, only 4% of the fed- al. 1991). Unfortunately, the phrases Park Act enunciate the explicit goal erally protected aquatic species in are widely used by the media, citi- of protecting biological integrity. the United States with recovery plans zens, policy makers, and some bi- No specific legislative mandate ex- have recovered significantly, com- ologists without adequate attention ists to protect biological diversity in pared with 20% of protected terres- to the concepts they embody. Pre- the United States, but such protec- trial species (Williams and Neves cise use of the terms integrity and tion became a central goal of the 1992). diversity can help set and achieve 1992 Earth Summit and the Global societal for goals sustaining global Biodiversity Protocol endorsed by Defining biological diversity resources; imprecise or inappro- many nations. The focal positions priate use may exacerbate biotic of the two concepts dictate that a The term biological diversity (or impoverishment-the systematic clear understanding of their mean- biodiversity) emerged as species ex- decline in biological resources ings is critical to developing effec- tinction rates began to increase dra- (Woodwell 1990). tive resource policy. matically (Myers 1979). The specter Although the related concepts of Our review of current concep- of mass extinctions, combined with integrity and diversity were devel- tions of integrity and diversity indi- huge gaps in biological knowledge, oped more or less independently (in- cates that resource policy would be has convinced many scientists that a tegrity in the study of aquatic sys- most effective if based on the more global biological crisis exists (Wil- tems, diversity in the study of comprehensive goal of protecting son 1985). Moreover, because bio- terrestrial systems), both apply to biological integrity. Specific policy logical diversity provides important all biotic systems. The US Clean shifts related to that goal include a aesthetic, cultural, ecological, sci- Water Act and Canada's National reliance on preventive rather than entific, and utilitarian benefits to reactive management and a focus on human society, the crisis is every- Paul L. Angermeieris an assistant unit landscapes rather than populations. one's concern (Ehrlich and Wilson leader at the National Sur- Biological We draw heavily from our experi- 1991). vey, Cooperative Fish and Wildlife Re- ence with but our One of the first formal defini- search of Fisheries aquatic systems, Unit, Department conclusions to terres- tions of termed and Wildlife apply equally biological diversity Sciences, Virginia Poly- trial it "the and technic Institute and State University, systems. variety variability among are and the Blacksburg,VA 24061-0321. James R. Aquatic systems appropriate living organisms ecological Karr is director of the Institute for En- models for illustrating general eco- complexes in which they occur" vironmental Studies, University of logical consequences of anthropo- (OTA 1987, p. 3). In addition, be- Washington, Seattle, WA 98195. genic impacts, because research is cause "items are organized at many

690 BioScience Vol. 44 No. 10 [biological] levels," biodiversity "en- Table 1. Levels of organization in three hierarchies used to characterize biological compasses different ecosystems, spe- diversity. These hierarchies are linked at the species-genome-population levels (see cies, genes, and their relative abun- text for details) but not precisely at any other levels. dance" (OTA 1987, p. 3). Other Taxonomic Genetic Ecological thorough discussions of biodiver- that Biota Genome Biosphere sity confirm multiple organiza- Chromosome set Biome and Kingdom tional levels (e.g., genes, species, Division/Phylum Chromosome Landscape ecosystems) are fundamental to the Class Gene Ecosystem/Community concept (Noss 1990, OTA 1987, Order Allele Population Reid and Miller 1989), thereby dis- Family it from the much sim- Genus tinguishing Species pler concept of species diversity.

Hierarchies The dynamics of oak populations in tional level at issue in any discus- a savannah landscape or of fungus sion. In estimating biodiversity in a Organizational hierarchies are use- populations in a stream-channel study area (e.g., a pond or conti- ful tools for understanding complex landscape, for example, may oper- nent), a researcher might count all biological phenomena. Several dis- ate at vastly different spatial scales. the taxonomic elements present, all tinct hierarchies-taxonomic, ge- The appropriateness of a spatiotem- the genetic elements present, or all netic, and ecological (Table 1)-are poral scale for studying a given ele- the ecological elements present. Even relevant to biological diversity. We ment depends on the organisms and in the unlikely event that all the follow Reid and Miller (1989) in questions at issue (Levin 1992). elements present are known, no ac- referring to biotic units at any level At ecological levels of organiza- cepted calculus permits integration within a hierarchy as elements. Thus, tion above population (see Table 1), of counts of elements across levels species and classes are taxonomic spatiotemporal bounds are often within a hierarchy (e.g., phyla and elements, genes and chromosomes arbitrary, integration is often loose, species) or across hierarchies (e.g., are genetic elements, and popula- and composition may be dynamic. species and genes). Arguably, no such tions and biomes are ecological ele- However, these elements are not calculus should be sought. ments. Levels are nested within each random assemblages, and they can Furthermore, the number of ele- hierarchy: a phylum comprises be defined on the basis of ecological ments at different organizational classes, a chromosome comprises attributes and societal benefits. For levels need not be correlated. For genes, and a landscape comprises example, the biota of the Chesa- example, there are more than twice communities. The hierarchies in peake Bay basin is a legitimate ele- as many marine phyla as terrestrial Table 1 are linked at the species- ment of biodiversity because it has phyla, but fewer marine species (Ray genome-population levels; any popu- objectively definable boundaries and and Grassle 1991). Similarly, lation of organisms has a taxonomic confers societal benefits (e.g., fish- Hoover and Parker (1991) found identity (species), which is charac- eries) that would not exist if the that species diversity and commu- terized by a distinct genome. How- component populations had not co- nity diversity of overstory plants ever, taxa may share genetic ele- evolved. were inversely correlated among sev- ments, and ecological elements may We do not distinguish commu- eral Georgia landscapes. In neither share taxa. nity and ecosystem as different hier- example is it unequivocal which sys- Specifying levels within hierar- archical levels but rather as comple- tem has more biodiversity. chies and elements within levels may mentary ways of viewing the same Failure to conceptually integrate be arbitrary. For example, ecolo- system (Karr 1994, King 1993). the multiple aspects of biodiversity gists may add an ecological level for Community perspectives are results in narrowly conceived com- guilds, or taxonomists may debate grounded in evolutionary biology parisons. For example, Vane-Wright the number of families within an and focus on the dynamics of organ- et al. (1991) measured biodiversity order. Because each level and ele- ism distribution and abundance; with an index of taxonomic diver- ment contributes to biotic variety ecosystem perspectives are grounded sity based on cladistics, which as- and value, all are appropriate tar- in thermodynamics and focus on the sesses distinctness of taxa. Similarly, gets of conservation. To focus as- dynamics of energy and materials Mares (1992) used a comparison of sessment or conservation on a single through and around organisms. Ei- mammal diversity (at several taxo- hierarchy or level (e.g., species) is to ther perspective can be applied at nomic levels) among South Ameri- arbitrarily ignore most biodiversity. any level in the ecological hierar- can biomes to infer that biodiversity Spatiotemporal scale is not pre- chy. is greater in drylands than in low- cisely defined by hierarchical level. land Amazon forest. These analyses elements are are Ecological typically Misconceptions valuable, but they cannot be defined by spatial extent (e.g., a interpreted as comprehensive (or pond community or a desert land- Because biological diversity is more even representative) assessments of scape), yet most levels can correctly comprehensive than species diver- overall biodiversity because genetic encompass a wide range of spatial sity, one must specify clearly the and ecological hierarchies were ig- scales (Allen and Hoekstra 1992). biological hierarchy and organiza- nored.

November 1994 691 A common misuse of the term Table 2. Elements, processes, and potential indicators of biological integrity for biodiversity makes it synonymous five levels of organization within three biological hierarchies. Assessing the with species diversity (Redford and integrity of a given area should incorporate indicators from multiple levels. Sanderson a that 1992), usage Hierarchy Elements Processes Indicators trivializes the broader meaning of Taxonomic Species Range expansion or Range size biodiversity and promotes miscon- contraction ceptions of conservation issues. Extinction Number of populations Palmer (1992) takes this misconcep- Evolution Isolating mechanisms tion to the extreme by depicting Genetic Gene Mutation Number of alleles loss as more Recombination Degree of linkage biodiversity nothing Selection or than extinction. incom- Inbreeding outbreeding species This depression plete view fails to recognize that Ecological Population Abundance fluctuation Age or size structure elimination of extensive areas of old Colonizationor extinction Dispersal behavior dramatic declines in Evolution Gene flow growth forest, Number of hundreds of distinct Assemblage Competitive exclusion species genetically Predation or parasitism Species evenness salmonid stocks in the Pacific North- Energy flow Number of trophic links west (Nehlsen et al. 1991), and the Nutrient cycling Element redundancy loss of chemically distinct popula- Landscape Disturbance Fragmentation tions from different of a Succession Number of communities portions Soil formation Persistence species range (Eisner 1992) represent significant losses of biodiversity, regardless of whether any spe- integrity is the primary directive for we contend that processes are more cies become extinct. Other misuses water policy in the United States. appropriately considered as compo- of the term stem from inclusion of The most influential definition of nents of integrity. Process diversity human-generated elements in assess- biological integrity was proposed is unlikely to provide an intuitive ments of an area's biodiversity by Frey (1975) and later applied by basis for distinguishing the biodi- (Angermeier 1994). Karr and Dudley (1981). It defined versity of different areas because the concept as "the capability of areas vary in process rates rather and a bal- than occurrence. All areas Defining biological integrity supporting maintaining process anced, integrated, adaptive commu- support the processes of meiosis, Biological integrity refers to a nity of organisms having a species speciation, disturbance, and preda- system's wholeness, including pres- composition, diversity, and function, but rates vary dramatically. ence of all appropriate elements and tional organization comparable to Moreover, changes in process rates occurrence of all processes at ap- that of natural habitat of the re- cannot be interpreted as changes in propriate rates. Whereas diversity is gion" (Karr and Dudley, p. 56). diversity unless the number of par- a collective property of system ele- Various forms of this definition now ticipating elements also changes. For ments, integrity is a synthetic prop- provide the basis for biotic assess- example, an increased rate of land- erty of the system. Unlike diversity, ment of surface waters by the US scape disturbance need not produce which can be expressed simply as Environmental Protection Agency more or fewer component commu- the number of kinds of items, integ- (EPA1990) and numerous states (EPA nities and populations. Although rity refers to conditions under little 1991a). processes clearly are essential to gen- or no influence from human actions; Two important distinctions be- erate and maintain elements, their a biota with high integrity reflects tween integrity and diversity emerge inclusion as components of biodi- natural evolutionary and biogeo- from this definition. First, system versity adds ambiguity without util- graphic processes. integrity is reflected in both the bi- ity. The concept of biological integ- otic elements and the processes that The second distinction between rity has played its largest policy role generate and maintain those ele- integrity and diversity is that only in the management of water re- ments, whereas diversity describes integrity is directly associated with sources where it first appeared in only the elements. Again, following evolutionary context. By definition, the 1972 reauthorization of the Reid and Miller (1989), we use pro- naturally evolved assemblages pos- Water Pollution Control Act (now cesses to refer to a broad range of sess integrity but random assem- Clean Water Act; CWA). The pri- evolutionary, genetic, and ecologi- blages do not. Adding exotic species mary charge of the 1972 CWA and cal processes (Table 2). Integrity or genes from distant populations subsequent amendments was to "re- depends on processes occurring over may increase local diversity but it store and maintain the chemical, many spatiotemporal scales, includ- reduces integrity. physical, and biological integrity of ing cellular processes giving rise to Most uses of the integrity con- the Nation's waters." This mandate genetic elements and ecosystem pro- cept focus on the community level has been the foundation for state cesses regulating the flow of energy of organization, but we suggest that and federal water-quality programs and materials. integrity also applies to most other over the past two decades. Although Although some authors (e.g., hierarchical levels in Table 1. Integ- implementation often has been ill- Noss 1990) explicitly include pro- rity of any biotic system can be as- focused (Karr 1991), the concept of cesses as components of diversity, sessed on the basis of attributes of

692 BioScience Vol. 44 No. 10 elements and processes important induced changes in biotic systems (Odum 1985) and support the hy- to its genetic or ecological organiza- frequently are more rapid and se- pothesis that ecological processes tion (see Table 2). However, the vere than those occurring naturally. are buffered from perturbation by concept may not apply to taxa above Thus, functional and evolutionary redundancy among elements (Bor- the species level, because most taxo- limits of the native biota provide mann 1985). For example, multiple nomic levels are artifacts of classifi- objective bases for selecting appro- interchangeable elements (e.g., spe- cation rather than functional biotic priate integrity benchmarks (Pickett cies) may drive a single process (e.g., entities. et al. 1992). For example, when nutrient cycle). Of course, given Because systems are hierarchical, forest harvest rates exceed regen- enough stress or element loss, any an element is generated and main- eration rates, integrity is reduced, process can be impaired. As stress tained (in part) by processes occur- resulting in loss of late-successional on system organization accumulates, ring at organizational levels above communities. When a river is nonlinear and threshold responses and below its own level (O'Neill et dammed, integrity is reduced, re- may result (see cases in Woodwell al. 1989). For example, the integrity sulting in declines of populations 1990). of a woodland community may de- adapted to the natural hydrological Many changes in diversity can be pend on colonization dynamics of regime. evaluated objectively only on the component populations as well as Evolutionary history should pro- basis of changes in integrity. For landscape-level disturbance dynam- vide the primary basis for assessing example, artificial nutrient enrich- ics. Thus, assessment of biological biological integrity. Even the value ment of a naturally oligotrophic eco- integrity should account for the in- of many artificial, human-generated system may increase local species fluence of processes at multiple or- elements (e.g., agricultural land- diversity yet eliminate a unique com- ganizational levels and multiple spa- scapes) depends on naturally evolved munity. Such a change may be inter- tiotemporal scales. elements and processes, such as ni- preted as either a gain or loss in trogen-fixing bacteria and soil for- diversity, but integrity is clearly re- mation. because of the duced because of the shift from Selecting benchmarks Sadly, perva- away sive effects of human actions, it is native conditions. Human impacts The ability to recognize objectively often difficult to characterize natu- in the Apalachicola River basin of and assess changes in integrity is rally evolved conditions. Because the southeastern United States re- critical for the concept's use in abilities to reconstruct historic sce- duced freshwater flow into the estu- policy. The first hurdle in recogniz- narios of biotic conditions are likely ary, resulting in elevated salinity ing change in integrity is the selec- to become even more impaired in and fish species diversity but loss of tion of a benchmark state against the future, such efforts should pro- productivity and nursery function which other states can be compared. ceed with the best information cur- (Livingston 1991). Management for Ecologists recognize that biological rently available. biological integrity would dictate systems are not strictly determinis- maintenance of lower species diver- tic but be and re- may develop (i.e., orga- Primacy of integrity sity higher productivity by nized) along multiple pathways as a storing the original salinity dynam- result of different initial conditions, Use of integrity as the primary man- ics. conditions in neighboring systems, agement goal avoids the pitfalls of Integrity goals also allow for natu- and the sequence of influential events assuming that greater diversity or ral fluctuation in element composi- (Pickett et al. 1992). For example, productivity is preferred. Knowledge tion. Loss of a particular element marine intertidal communities are of the couplings between biotic ele- (e.g., species) or replacement by a influenced by predation, distur- ments and processes is based largely regionally appropriate one need not bance, competition, physiological on observations of stressed ecosys- indicate a loss of integrity unless the tolerances, and colonization from tems. Experimental studies of whole processes associated with the offshore. The relative importance of lakes exposed to nutrient enrich- element's maintenance become im- each process and the relative abun- ment and acidification indicate that paired. For example, natural meta- dances of species at a given site species composition responds more population dynamics often include depend on coastal circulation quickly and recovers more slowly local, temporary extinctions bal- (Roughgarden et al. 1988). Varia- than processes such as primary pro- anced by recolonizations via dis- tion in elements attributable to natu- duction, respiration, and nutrient persal (Hanski and Gilpin 1991). ral processes does not represent a cycling (Schindler 1990). Such losses of populations do not variation in integrity, but variation In a review of aquatic ecosystem indicate losses of integrity unless caused by humans does. and mesocosm responses to stress, rates of extinction, dispersal, or Regier (1993) contends that states Howarth (1991) found numerous recolonization are altered, as might other than those evolved naturally examples of shifts in biotic elements occur in an artificially fragmented can provide benchmarks for integ- that were unaccompanied by changes landscape. rity. Although unnatural states may in process rates, but process changes The inadequacy of diversity as a be desirable for aesthetic, utilitar- were always accompanied by shifts policy directive is perhaps clearest ian, or other reasons, they cannot in elements. These patterns are con- in the evaluation of situations where provide an objective basis for as- sistent with observations and pre- humans add elements such as trans- sessing biological integrity. Human- dictions from forest ecosystems ferred genes, exotic species, or agri-

November 1994 693 Table 3. Representativesof five classes of factors that organize ecological systems been useful in selecting ecological and a framework for provide assessing ecological integrity. Some factors are indicators to assess (Karr 1991, Karr in or terrestrial especially applicable aquatic (A) (T) systems. et al. 1986) and tactics to restore (Gore 1985) integrity in aquatic sys- Class Factors tems. can be as- Physiochemical conditions Biological integrity Temperature Salinity sessed attributes pH Precipitation (T) through diagnostic Insolation Oxygen (A) or indicators, which ideally are sen- Nutrients Contaminants sitive to a range of stresses, able to stress-induced variation base distinguish Trophic Energy source Energy content of food from natural relevant to Productivity Spatial distribution of food variation, Food particle size Energy transfer efficiency societal concerns, and easy to mea- sure and interpret. Several authors Habitat structure Spatial complexity Vegetation form (T) (e.g., Karr 1991, Noss 1990, and Cover and refugia Basin and channel form (A) Schaeffer et al. offer exten- Substrate 1988) Topography (T) composition (A) sive lists of indicators of Soil composition (T) Water depth (A) potential Vegetation height (T) Current velocity (A) ecological integrity (also see Table 2); others have listed indicators of Temporal variation Diurnal Predictability genetic integrity (Lande and Barrow- Seasonal Weather (T) Noss In Annual Flow regime (A) clough 1987, 1990). practice, elements are used more fre- Biotic interactions Competition Disease quently than processes as indicators Parasitism Mutualism of integrity because elements are Predation Coevolution typically more sensitive to degradation, more fully understood, and cultural landscapes to natural sys- tion biology (Soule 1985) were less expensive to monitor. Thus, tems (artificial biological diversity; intended to protect products and biodiversity is an important indica- Angermeier 1994). Artificial ele- processes of biogeography and evo- tor of biological integrity. ments reduce integrity through lution. Thus, current definitions of The complexity of biotic systems widely documented effects on na- biodiversity should incorporate ex- dictates that integrity assessments tive elements and processes (Karr et plicit native criteria. should incorporate a variety of indi- al. 1986, Taylor et al. 1984, Vitousek In sum, biological integrity en- cators (including elements and pro- 1990) and should be excluded from compasses element composition cesses) from multiple organizational evaluations of biodiversity (Anger- (measured as number of items) and levels and spatiotemporal scales. The meier 1994). process performance (measured as index of biotic integrity (IBI) repre- Some (e.g., Palmer 1992) argue rates) over multiple levels of organi- sents a successful approach for that artificial elements are compo- zation; it is assessed in comparison incorporating information from nents of biodiversity and therefore with naturally evolved conditions multiple indicators into a single appropriate targets of biological within a given region. Biological numerical index (Karr 1991, Karr et conservation. We reject this argu- integrity is thus generally defined as al. 1986). Conditions observed in ment for several reasons. First, cul- a system's ability to generate and the system being assessed are com- turally or technologically derived maintain adaptive biotic elements pared to region-specific expectations elements rarely perform life-support through natural evolutionary pro- for an undegraded system, (i.e., the services as effectively as native ele- cesses. Current loss of biological reference condition). ments (Ehrlich and Mooney 1983). diversity is tragic, but loss of bio- The original IBI incorporated nu- Second, technology applied on mas- logical integrity includes loss of di- merical criteria on species composi- sive spatial scales erodes biological versity and breakdown in the pro- tion and diversity, trophic composi- integrity, ultimately leading to bi- cesses necessary to generate future tion, population density, tolerance otic impoverishment. And, third, diversity. to human impacts, and individual including artificial diversity in con- health to assess integrity of lotic fish of le- communities. The IBI has been ceptions biodiversity wrongly Ecological indicators used gitimizes management strategies that successfully in more than 20 states erode native diversity. To assess biological integrity, one of the United States and in Canada, Conceivably, through genetic en- should be familiar with regional France, India, Poland, and Venezu- gineering, species introduction, land- organizing processes and elements, ela. Similar protocols (some using scape modification, and other tech- including how they are influenced aquatic invertebrates) also have been nologies, we could manufacture a by human actions. A conceptual or- developed for reservoirs, lakes, and biota with more elements, and thus ganization with five classes of inter- estuaries (Deegan et al. 1993, EPA more diversity, than the naturally acting factors-physicochemical 1991b, Ohio EPA 1988). Efforts to evolved one, even to the exclusion conditions, trophic base, habitat apply such assessment approaches of native elements. In contrast, the structure, temporal variation, and in terrestrial systems have lagged normative postulates of conserva- biotic interactions (Table 3)-has behind those in aquatic systems, but

694 BioScience Vol. 44 No. 10 they can succeed if defensible crite- hindered natural recovery processes ages in a stand (Lippke 1993) as ria for appropriate indicators are (Franklin et al. 1988). On the other measures of biodiversity, harvest developed. hand, many systems are remarkably schedules would mimic patterns of responsive to appropriate restora- natural disturbance (Hunter 1990). tion efforts. Years after Ecological restoration a massive Appropriate roles of diversity in channelization project in the Kissim- resource policy are in establishing The goal of ecological restoration is mee River in Florida, partial re- conservation priorities, siting re- to produce a self-ststaining system establishment of the flow regime serves, and indicating program suc- as similar as possible to the native quickly restored plant, invertebrate, cess. However, policy makers must biota. But biological, socioeco- fish, and bird assemblages (Toth agree on which organizational lev- nomic, or technological constraints 1993). As knowledge of ecological els and elements should be protected. may limit our ability to attain that processes and the technology to Species and communities are com- goal despite the best intentions. For mimic those processes advance, we monly used to assess an area's con- example, past extinctions of many expect ecological restoration to take servation value, but genetic elements Great Lakes fish stocks prevent re- its place as a successful discipline. are rarely used. Gap analysis, for storing integrity to those ecosystems example, combines information on even if exotic and toxic species Policy implications landscape-scale vegetation types chemicals could be removed. Simi- with assumptions about the habitat larly, as rangeland degradation Despite spending hundreds of mil- associations of terrestrial vertebrates progresses, the costs and time for lions of dollars on endangered spe- and butterflies to establish regional restoration become increasingly pro- cies, the United States continues to conservation priorities (Scott et al. hibitive (Milton et al. 1994). Thus, lose biodiversity. We ascribe much 1993). restoration goals must be based on of this loss to ineffective policy that Policy effectiveness also could be social and political constraints as emphasizes piecemeal conservation improved by shifting focus from well as biological potential. Once a of the elements of diversity rather populations and species to land- goal (benchmark state) is selected, than comprehensive protection of scapes. The organizational processes however, assessing restoration suc- the integrity of systems supporting and ecological contexts that main- cess is analogous to assessing integ- those elements. Two major shifts tain populations typically operate rity under other circumstances, are needed to produce more effec- at larger spatiotemporal scales than which includes identifying organiz- tive resource policy. First, goals of the populations themselves (Pickett ing processes and selecting appro- biological conservation and resto- et al. 1992). Because human im- priate indicators. ration should focus on protecting pacts are applied at landscape scales, Restoration methods usually integrity (Karr 1993), especially the management prescriptions should be mimic recovery from natural per- organizational processes that gener- focused at the same scales. Land- turbations and reflect important ate and maintain all elements, rather scape-scale approaches are especially organizational processes. Common than focusing on the presence or important in managing aquatic sys- approaches for aquatic systems in- absence of particular elements. Such tems, which can rarely rely on high- clude manipulating water quality, an approach is more likely to pre- profile species (e.g., bald eagle or habitat structure, hydrology, ripar- vent endangerment of elements and grizzly bear) to garner public sup- ian/watershed vegetation, and (less should be more cost-effective than port for protection. frequently) animal populations emergency efforts to pull them back Riparian zones and floodplains (Gore 1985, Osborne et al. 1993). from the brink of extinction after are critical landscape components Restoration of terrestrial systems serious degradation. Emergency tac- linking aquatic and terrestrial sys- typically focuses on establishing tics may be necessary where a focus tems; they regulate aquatic habitat native vegetation and manipulating on integrity fails to protect an ele- formation, as well as entry of water, succession. ment, but they should not be the nutrients, and organic material into To maximize effectiveness, resto- primary basis of conservation, as in aquatic habitats (Gregory et al. ration efforts should employ and current policy. 1991). Thus, management ap- encourage natural ecological pro- Adoption of policy goals to pro- proaches focusing on strictly aquatic cesses rather than technological fixes tect integrity would help avoid dif- components (e.g., designation of a and should incorporate spatiotem- ficult resource allocation problems stream reach as wild and scenic or as poral scales large enough to main- such as estimating specific flows critical habitat for an imperiled spe- tain the full range of habitats neces- needed to sustain populations of cies) are unlikely to be effective over sary for the biota to persist under endangered fishes in the Colorado the long term. Application of integ- the expected disturbance regime. River or endangered birds in Platte rity goals and landscape approaches Failure to recognize important eco- River wetlands. In fisheries, manag- are perhaps nowhere more impor- logical relationships can result in ing for integrity would not allow the tant (or more politically challeng- counterproductive efforts. In the widespread practice of stocking non- ing) than in estuaries or in anadro- Mount St. Helens (Washington) native fishes to be construed as en- mous fisheries, which depend on blast area, for example, seeding hancing biodiversity. In forestry, interactions among terrestrial, fresh- slopes with grass and removing rather than using the range of stand water, marine, and even atmospheric woody debris from streams actually ages in a forest or the range of tree systems.

November 1994 695 Implementation of integrity goals measures analogous to the Endan- of Illahee: Journal for the North- is likely to challenge the leadership gered Species Act to prevent impor- west Environment and Julie Ann of government agencies. Protection tant or unique ecosystems and land- Miller of BioScience-aided us im- of biological integrity could be en- scapes from being destroyed. measurably in expressing our ideas hanced by restructuring tax and sub- more clearly. The Cooperative Fish sidy programs to eliminate conser- Societal choices and Wildlife Research Unit is jointly vation disincentives for private supported by National Biological landowners and to distribute con- The causes of environmental degra- Survey, Virginia Department of servation costs and benefits equita- dation and loss of biodiversity are Game and Inland Fisheries, and Vir- bly (Carlton 1986). Traditional ag- rooted in society's values and the ginia Polytechnic Institute and State ricultural, fisheries, forestry, game ethical foundation from which val- University. management, and mining agencies ues are pursued (Orr 1992). Solu- must replace their narrow, commod- tions are likely to emerge only from References cited ity and harvest-oriented philoso- a deep-seated will, not from better with innovative in- Allan, J. D., and A. S. Flecker. 1993. Biodi- phies perspectives technology. Adopting biological versity conservation in running waters. founded on a broader range of so- tegrity as a primary management BioScience 43: 32-43. cial concerns, longer time frames, goal provides a workable framework Allen, T. F. H., and T. W. Hoekstra. 1992. and more interagency cooperation for sustainable resource use, but Toward a Unified Ecology. Columbia Critical to- societal University Press, New York. (Salwasser 1991). steps fostering integrity requires Angermeier, P. L. 1994. Does biodiversity ward managing for biological integ- commitment well beyond govern- include artificial diversity? Conserv. Biol. rity include establishing scientifi- ment regulations and piecemeal pro- 8: 600-602. cally defensible benchmarks and tection. Such a commitment includes Bormann, F. H. 1985. Air pollution and assessment criteria. limits on human forests: an ecosystem perspective. Bio- self-imposed popu- 434-441. these are lation size and resource Science 35: Although steps poten- consump- Carlton, R. L. 1986. Property rights and tially contentious, current uses of tion, rethinking prevailing views of incentives in the preservation of species. integrity goals indicate that success land stewardship and energy use, Pages 255-267 in B. G. Norton, ed. The is attainable. Management programs and viewing biological conservation Preservation of Species. Princeton Uni- for Kissimmee River, Ohio surface as essential rather than as a versity Press, Princeton, NJ. luxury Deegan, L. 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