342 COMMENT•m¾ VOL. 32, No. 4

MCLEOD, M.A. AND D.E. ANDERSON. 1998. Red-shoul- CHESNE¾.1998. Status and trends of the Ashy Storm- dered Hawk broadcastsurveys: factors affecting detec- petrel on southeastFarallon Island, California, based tion of responsesand population trends. J. Wildl. upon capture-recaptureanalyses. Condor 100:438-447. Manage.62:1385-1397. TAYLOR, B.L. AND T. GERRODETTE. 1993. The uses of sta- P^GEL,J.E. ANDD.A. BELL.1997. Reply to Cade et al. tisticalpower in conservationbiology: the Vaquitaand regarding de-listingthe American Peregrine Falcon. Northern SpottedOwl. Conserv.Biol. 7:489-500. Wildl. Soc. Bull. 25:739-742. TITUS, K. AND M.R. FULLER. 1990. Recent trends in counts , •D B.E. NORTON.1996. De-listing the of migrant hawks from northeastern North America. American Peregrine Falcon: Is it premature? Wildl. J. Wildl.Manage. 54:463-470. Soc. Bull. 24:429-435. W•,D, J.M. •'4D P.L. K•NNED¾.1996. Effects of supple- REYNOLDS,R.T ANDS.M. JoY. 1998. Distribution, territory mental food on sizeand survivalof juvenile Northern occupancy,dispersal, and demography of Northern Goshawks. Auk 113:200-208. Goshawkson the Kaibab Plateau, Arizona. Unpubl. WHITE, C.M. ANDL.E IrdFF.1998. Language use and mis- Final Rep. for Arizona Game and Fish, Heritage Pro- applied, selective "science"; their roles in swaying ject No. 194045. public opinion and policy as shownwith two North ROMESBURG,H.C. 1981. Wildlife science:gaining reliable American raptors.Pages 547-560 in Chancellor,R.D., knowledge.J. Wildl.Manage. 45:293-313. B.-U. Meyburg andJJ. Ferrero [EDs.].Holarctic birds --. 1989. More on gaining reliable knowledge:a re- of prey. Adenex and World Working Group of Birds ply.J. Wildl.Manage. 55:767-773. of Prey, Mfirida, Spain. ROSENFIELD,R.N., J. BIELEFELDT,D.R. TREXELAND T.C.J. WHITE, G.C. ANDR.A. GARROTT.1990. Analysisof wildlife DOOLITTLE.1998. Breeding distribution and nest-site radio-tracking data. Academic Press,New York, NY habitat of Northern Goshawksin Wisconsin.J. Raptor U.S.A. Res. 32:189-194. --, A.B. FRANKLINAND J.P. WARD. 1995. Population SCHMIEGELOW,F.K.A., C.S. M^CHT•S •D S.J. HANNON. biology.Pages 1-25 in USDI Fish and Wildlife Service, 1997. Are boreal birds resilient to forest fragmenta- Recoveryplan for the Mexican SpottedOwl, Chap. 2. tion? An experimental studyof short-term community Vol. II. Albuquerque, NM U.S.A. responses.Ecology 78:1914-1932. WOODBRIDGE,B. ANDPJ. DETRICH.1994. Territory occu- SQUIP•S,J.R. •ND R.T. REYNOLDS.1997. Northern Gos- pancy and habitat patch size of Northern Goshawks hawk (Acdpitergentilis). In A. Poole and F. Gill [EDS.], in the southern Cascades of California. Stud. Avian The birds of North America, No. 298. The Academy Biol. 16:83-87. of Natural Sciences,Philadelphia, PA U.S.A. SYDEMAN,W.J., N. NUR, E.B. MCLARENAND GJ. Mc- Received 1 August 1998; accepted 24 August 1998

j RaptorRes. 32 (4) :342-348 ¸ 1998 The Raptor ResearchFoundation, Inc.

DETERMINING THE STATUS OF NORTHERN Gosi-•w• IN THE WEST: Is OUR CONCEPTUAL MODEL CORRECT?

STEPHEN DESTEFANO U.S. GeologicalSurvey, Arizona CooperativeFish and WildlifeResearch Unit, 104 BiologicalSciences East, Universityof Arizona,Tucson, AZ 85721 U.S.A.

In federal district court in Tucson, Arizona recently,a owls.Defenders of Wildlife, as the plaintiff, was suing to case was heard regarding the statusof the Endangered stop the development. Owls had been seenjust north Cactus Ferruginous Pygmy-owl(Glaucidium brasilianum and south of the boundary of the property in question, cactorum)and developmentin the Tucson basin (Defend- and the attorney for the defense built part of her case ers of Wildlife vs. Amphitheater School District). The on the fact that an owl had not actuallybeen seen inside western population (Arizona) of the CactusFerruginous the property boundary. She used this "uncertainty" Pygmy-owlhad been listed in 1997 under the Endan- about the owls' use of the property, as well as other as- gered SpeciesAct (ESA), and a local schooldistrict want- pects of its little-known ecologyin Arizona, to her advan- ed to build on an area allegedly used by one or more tage and stated in court "there comesa point where the DECEMBER 1998 COMMENTARY 343 best evidence available isn't good enough" (Nintzel izens, and to deemphasize the concept of "us" vs. 1998). "them" that so often plagues conservationdebates. That statementis a big problem for biologistsin court, and one that could alwaysbe usedagainst us. The "best A RECENT HISTORICAL PERSPECTIVE evidence available" will alwaysinvolve uncertainty be- Northern Spotted Owl as Conservation Model. It cause our best data are usually sample data, which, by would be a mistaketo evaluatethe statusof any candidate definition, contain uncertainty (Ramsey and Schafer speciesfor listing under the ESA, and particularly any 1997), and we will rarely haveall the data we need. "Un- forest raptor, without first considering the history and certainty" is not a negativeconcept in science,but part implications of the Northern Spotted Owl issue in the of the process(Murphy and Noon 1991, Williams et al. Pacific Northwest. Yaffee (1994) called the spotted owl 1996). The courts, however,view uncertainty as equiva- lent to "a shadow of doubt." If conservationists are al- controversya "watershed event" in resource and envi- ronmental policy. In many wayswe entered a new era •n wayscharged with the burden of proof, we will more of- ten than not lose in court, which is where conservation conservation,with myriad implicationsin policy,poliucs, and public relations. Important among them wasa stron- and resource management decisionsare made with in- ger focus on ecosystemsas the public, through the me- creasingfrequency. dia, sawthe extent of the destruction of old-growthforest The status of the Cactus Ferruginous Pygmy-owlhas (i.e., native forest unaltered by human activitieswith nat- implicationsfor a small part of the world--the few par- ural processes[e.g., hydrology,succession, wind-throw, cels of undevelopedland in the unplanned and overde- velopedTucson basin of southernArizona. The statusof fire] intact). The alteration of ecosystemsin North Amer- another raptor, the Northern Goshawk(Accipiter gentilis ica was not new--consider, for example, weftands, prai- ries, and deserts--but the focus and level of attention was atricapillus)has much broaderimplications. The goshawk •s distributed in forested areas throughout much of somethingdifferent. Equallyimportant wasa demonstra- North America, and the implicationsof listing this spe- tion of the power and reach of the ESA. This law became ciesas Threatened or Endangered under the ESA are far- a potent tool for environmentalists;any citizen could pe- reaching and important, perhapseven more so than the tition for a listing (Rohlf 1989), and if listing occurred, listingof the Northern SpottedOwl (Strixoccidentalis caur- there was legal power to alter the rate of resource ex- traction. ina) as a Threatened Speciesin 1990. Like the Northern Spotted Owl, the goshawkis a forest raptor dependent, Bridging concerns over the loss of old-growth forests at least partially, on older forest, and thus millions of and the power of the ESA to change that trend wasper- dollars worth of timber are involved. This certainly haps an ideal species:a somewhatmysterious but easily heightensthe interest of the public, the Congress,and photographed (and thus newsworthy)owl that was an the courts.In addition, the goshawkoccurs over a much old-growthobligate (Forsmanet al. 1984). The listing of broader geographicarea than the Northern SpottedOwl. the Northern Spotted Owl under the ESA as a Threat- Regardlessof the final decisionto list or not list the gos- ened Speciesbrought harvestof old-growth timber in the hawk, court is likely where we are headed. region to a standstill,an environmental issueto the at- This paper representssome thoughtson the statusof tention of the nation, and a president to Portland, goshawksin the West,including a reviewof recent events Oregon for a national meeting. The old growth-Northern that helped shape the debate over Endangered Species Spotted Owl model of controversy,confrontation, and management,a summaryof availabledata on goshawk conservationbecame a template for protection of nature. ecology,some suggestionsfor additional data that could A Parallel Course?During the latter stagesof the spot- or shouldbe collected,and somequestions on how pro- ted owl issue,Crocker-Bedford (1990) published a paper fessionalbiologists, environmental groups, and societyin on goshawkreproduction and forest managementin Ar- general invoke and use the ESA. It is also a forum for izona, citing a correlation between excessivetimber har- me to air some of my own uncertaintiesregarding the vest and lossof goshawkbreeding territories. Petitions to statusof this speciesand some suggestionsfor coursesof list the goshawksoon followed (Kennedy 1997). At issue action for its management and conservation.I hope that again was not only concern for the continued existence any or all of this fostersadditional discussion. I focuson of a species,but a desire to stop logging in old-growth goshawkswest of the 100th meridian, and refer to this as forest: not just the mesic forests of Douglas-fir (Pseudo- the West,because that has been the geographicscope of tsugamenziesii), western hemlock (Tsugaheterophylla), and recent listing petitions (U.S. Fish and Wildlife Service firs (Abiesspp.) westof the CascadeRange, but the much 1998b) and includes the area where most of the recent more widespread drier forests of Ponderosa pine (P, nus ecological and demographic research has occurred ponderosa),lodgepole pine (P contorta),and mixed com- (Block et al. 1994, Kennedy1997, Squiresand Reynolds fers of the interior West. We had just seen a demonstra- 1997). Finally,I make liberal use of the pronoun "we" tion of the power of the ESA to slow the pace of timber throughout the paper to emphasizethe idea that conser- harvest to the benefit of Northern Spotted Owls;perhaps vation issuesare the concern and responsibilityof all cit- this was the best course for the goshawk. 344 COMMENTARY VOL. 32, No. 4

Spottedowls

Goshawks I

Available forest

cover Increasingmean Decreasingvariance

Forest structure F•gure1. Theoreticalgraphs comparing Northern Spotted Owl andNorthern Goshawk use (e.g., for nestor roost s•tes)of old-growthforest structure (e.g., density of largetrees, high overstorycanopy closure) to foreststructure availableon the landscape.Preponderance of old-growth characteristics increases to the rightof the x-axis.Northern Goshawksuse a widerrange of foreststructural stages than NorthernSpotted Owls, but useolder forest more than it is availableon the landscape.See text for additionaldiscussion.

GOSHAWKS AND OLD-GROWTH FOREST corporated timber harvest as a mechanismto achievethe Early petitionsto list the goshawkprompted a thor- desiredmix and distributionof foreststructural stages. ough examinationof paststudies and a hostof new stud- Fig. 1 illustrates,in a very generalway, one idea of how •es by independent researchersin severalwestern states Northern SpottedOwls, goshawks, and forestcover may (Squires and Reynolds1997, Daw et al. 1998). Most of relateto one anotherover a broadgeographic scale. The thesestudies focused on nestinghabitat, partly because x-axiscan be any forest structurevariable or combination of the importanceof breedingbiology to the ecologyand of variablesthat characterizeold-growth forest (increas- management of goshawks,but alsobecause it wasdifficult ing sizeof trees,density of largetrees, and/or overstory to approachresearch on thiselusive species in anyother canopyclosure); the further right one goeson the x-axis way.These studiesmay be criticizedas a duplicationof the more prevalentare thosecharacteristics. The y-axis effort, but when one examinesthem as a group, an in- representsincreasing frequency of occurrence;for owls terestingand important pattern emerges:goshawks, re- or goshawksit couldbe numberof nestor roostingsites; gardlessof region or forest type, tend to select stands for availableforest cover it is the frequencyof occurrence w•th large trees (e.g., >53 cm dbh; Daw et al. 1998) and for a particularstructural stage on the landscape.Al- relativelyhigh canopyclosure (e.g., >50-60%; Ward et thoughthese graphs are theoretical,data existsto sup- al. 1992,Daw et al. 1998) for nesting(see Daw et al. 1998 port them (Rippleet al. 1991,Siders and Kennedy1996, for a summary of research). McGrath 1997). The top graph showsthat Northern I believeit wasa combinationof our recentexperience SpottedOwls are found mostlyin older forest,with lim- w•thNorthern SpottedOwls and the patternof goshawks ited variationaround the mean, indicatingthe impor- nesting in forest standswith old-growthcharacteristics tanceof olderforest to their existence.The secondgraph that led many to believethat the goshawkwas an "old- showsgoshawks as being found in a widervariety of forest growth species."Reynolds et al. (1992) describedwhat structuralstages compared to spottedowls. Older forest m•ght be optimal goshawkhabitat in the southwestern is important to goshawks,but goshawksare more of a U S.: it includednot only a large percentageof the land- forestgeneralist than are spottedowls. Finally, the third scapein older forest,but alsoa mix of standtypes and graph illustratesgeneral forest structure acrossmuch of ages that providesfor a variety of prey and takes into the West, based on measurements taken at random accountforest stand dynamics(Graham et al. 1994). Im- points as an index of "availability"(Manly et al. 1993). portantly,the southwesternmanagement guidelines in- Compared to the graph for goshawks,the mean is cen- DECEMBER 1998 COMMENTARY 345 tered over younger forest and there is wider variance. cover types throughout the West (Squires and Reynolds The relative positions of these three graphs probably 1997), and in that sensecan be viewedas forestgener- would be expected even for pristine forests.Today, how- alists.For any given forest cover type, however,goshawks ever, forestsin the West have clearly been forced to ear- tend to nest in standswith large trees and high canopy lier structural stages (i.e., forest structure has been closure; their choice of nest sites could relate to micro- "pushed" to the left side of the graph). climate, protection from predation, or something else, The changingstructural stage of forestsis a trend that but the pattern is well-documented (Daw et al. 1998) should and does concern us. Setting forest succession Older forest may also be important in the postfledgmg back through clearcutting old-growthforest west of the family area (PFA) (Kennedy et al. 1994, Daw 1997). As Cascade Range has had important implications for one looks at forest cover at increasingdistances from the Northern Spotted Owls•enough to list the species as nest, however,older forest becomesless prevalent (Daw Threatened. The effect that multiple entry selective cut- 1997, Desimone 1997), and possibly less important ting on Ponderosapine and other dry forest tree species (McGrath 1997). While older forestmay be lessprevalent has had on goshawksis also of concern, but the impli- on the landscapein general becauseof past timber man- cationsare lessclear. Given that forestmanagement prac- agement activities,older forest away from the nest may ticesare likelyaffecting even thisrelatively versatile forest be lessimportant to breedinggoshawks than older forest raptor, the question becomeshow to respond to that con- immediately around the nest. cern. One possibleresponse is to list the goshawkas an Prey. Goshawkshunt in older forest and may even pre- EndangeredSpecies, which would likely stop or at least fer it if it is available (Bright-Smith and Mannan 1994, slowthe cutting, as it did for the Northern Spotted Owl. Beier and Drennan 1997), but they alsohunt in a variety Basedon this logic, a seriesof petitionsby environmental of vegetativecover. For example, in eastern Oregon it was groups to list varioussegments of the goshawkpopula- not uncommon to see goshawkshunting in open sage- tion in the West began in the early 1990sand has contin- brush (Artemisiaspp.), and we often found ground-squir- ued unsuccessfullywell into the decade (U.S. Fish and rels (Spermophilusspp.) in prey remains (Cutler et al. Wildlife Service 1998b). 1996). In addition, some of the most important prey of goshawksare lagomorphsand grouse, particularly snow- THE DATA WE HAVE shoehares (Lepusamericanus) and Ruffed Grouse (Bonasa Demography. In responseto the petitions to list, Ken- umbellus).These speciesprovide more biomassthan most nedy (1997) reviewedthe availablepublished literature other prey, and reproductive output in goshawksmay be on the subspeciesA. g. atricapillusin North America and negativelyaffected when large-biomassprey are not avad- conducted analyseson demographic data from two pop- able (Doyle and Smith 1994, Iverson et al. 1996). Snow- ulations in New Mexico and Utah. She evaluated the shoe hares and Ruffed Grouse inhabit early successional claim that goshawkpopulations were declining in North stageforest and are key speciesin the ten-year cycle m America, statingthat evidenceof a declinewould include northern North America (Doyle and Smith 1994). There range contractions,decreases in density,or decreasesin are alsovery important relationshipsbetween prey abun- fecundityor survival,which might translateinto a nega- dance and availabilityfor foraging goshawks,and forest tive rate of population change (h). Based on this ap- structure plays an important role in goshawk foraging proach, she concluded that there wasno evidenceto sup- habitat (Beier and Drennan 1997, DeStefano and Mc- port the contention that goshawk populations were Closkey1997). declining. Importantly, she stated that this result could THE DATA WE NEED be interpreted in two ways:goshawk populations are not declining, or goshawkpopulations are declining but the Demography.Demographic data are vital, but studies decline has not been detected. The latter interpretation must be properly designedand be long-term or the re- would be a Type II error and, as such, is of concern to sults are difficult, if not impossible,to interpret (De- conservationbiologists (Steidl et al. 1997). Stefanoet al. 1994). A studyof goshawkdemography and Kennedy's(1997) reviewwas an important and neces- habitat use on the KaibabPlateau, which is probablythe sary step in examining the status of goshawks.Cole longestrunning studyon the speciesto date, is approach- Crocker-Bedford and Shawn Smallwood have taken issue ing a long-term basis.However, funding waxesand wanes with Kennedy'sapproach and have pointed out problems as the threat of listingthe goshawkcomes and goes (R.T. that can arisein collectingand interpretingdemographic Reynoldspets. comm.). Unreliable funding for needed data. However,demographic information, as difficult as long-term studies is short-sighted and counter-produc- it is to collect, is vital to understandingpopulation dy- tive. The U.S. Forest Service and other federal agencies namics: the available demographic data on any species must commit to studiesthat run greater than 10 years, consideredfor listing must first be assessed(sensu Ken- as the answers we need cannot be determined in two to nedy 1997) before collectionof additionaldemographic three years.Estimating the rate of populationchange data can be improved (sensuSmallwood 1998). for a speciessuch as the goshawkmay simply be too d•f- Habitat. Goshawkscan be found in a variety of forest ficult and take too long for the listing process.Nonethe- 346 COMME•T•m¾ VOL. 32, No. 4 less, data on reproductive rates and survival are critical America (Norse 1990). In frustration to conserve rem- to understandingthe ecologyof goshawksand their likely nant patchesof old-growth,or any native ecosystem,the responseat a population level to changesin their habitat. strongesttools of persuasionare going to be the ones It is worth considering if and how one can design and most used. One such tool is the ESA. In the case of the implement good demographic studieson goshawksbe- Northern Spotted Owl and the temperate old-growth fore we dismissthem altogether. rainforest of the Pacific Northwest, this approach was Related to this, listing decisionsbased on migratory prudent and necessary;listing the owl was the right countsof goshawkswould alsobe problematic,given the course of action. However, before we take this action for •mportance and influence of cyclic prey in the boreal the goshawkand list it as Threatened or Endangered,we forest and the capability of goshawksfor long-range need to ask if it is in the best interest of the speciesand movements in response to declining prey. It would be the ESA itself. Listing decisionsshould be made regard- d•fficult to assesstrends in goshawknumbers based on lessof politics (Sidle 1998), but politics are surelya part migratory count data alone, even over a long period of of the process,and political oppositionto the ESA is real time. However, migratory counts combined with other and strong. I am not advocating a weak stance on pro- demographicdata could provide important additionalin- tecting species,just a reasoned one that considersour formation on goshawks(Bildstein 1998). credibility as scientistsand a judicious use of the ESA. Habitat. With some exceptions (e.g., A. g. laingi in So, am I concerned about the status of goshawksin southeastAlaska, A. g. apachein the Southwest),another North America? Yes. Am I concerned about the loss of studyon nestinghabitat of goshawksin the Westmay not old-growthforest? Definitely. Should we list the goshawk be necessary.However, there remainsplenty to learn re- to protect it and old-growthforest habitat?Probably not. garding how juvenile goshawksuse habitat within PFAs This position may sound contradictory, given the case and how adults use habitat to forage. Also,very few hab- made for goshawks'use of old-growthforest, but it hinges itat studies have been conducted in winter. on severalconsiderations, such as the variety of structural Documenting the distribution of all forest structural stagesthat goshawksuse, the importance of some early stages,including mature or old-growthforest, acrossthe successionalstage forest prey, the overwhelmingpressure West would be an important step in the statusreview pro- to list manyspecies in the U.S.--severalof whichare truly cess.Such documentationwill be important for a number threatened with extinction--that taxes our limited re- of wildlife species,including goshawks,and hasbeen sug- sources,and a concern that we invoke the ESAjudicious- gested by Crocker-Bedford (1998) and Smallwood ly. (1998). Recent efforts of the U.S. Fish and Wildlife Ser- I recommend a different approach. I think there is vice in the latest review of the statusof goshawksin the time and opportunity to manage for goshawksin the West showed how poorly information on forest stand Westwithout listing.However, goshawks may currentlybe structure is documented and/or available in a usable for- in the same position that spotted owlswere in one to two mat (U.S. Fish and Wildlife Service 1998a). Low response decadesago. That is, some options remain, but if action rates on questionnairessent to land management agen- is not taken now, far fewer options will be availablelater. cies and a wide varietyof documentation,both in quality To exercise some of our options now, I suggestthe fol- of •nformation and methods used, make decisions on lowing: (1) provide funding and support to maintain cur- goshawkstatus based on habitat availabilityproblematic. rent research similar to that on the Kaibab Plateau, and Although methods to gather and compile data on cur- perhaps two or three additional and coordinated studies rent forest conditions across the West need to be im- in other regions; (2) continue coordinated efforts to proved, future decisionson the statusof goshawksought identify and map areasof remaining older forestsacross not to be made based on the availabilityof old-growth the West; (3) support the testing and evaluationof em- forest alone. Concurrent data on demography and dis- pirical habitat models that have been developedin the tr•bution of goshawksare alsoneeded. Southwest (Reynolds et al. 1992) and Northwest (Mc- Prey. Becauseprey resourcesare so important to the Grath 1997); (4) conducton-site experiments to measure population dynamicsand distribution of goshawks,ad- goshawkresponses to silviculturaltreatments; and (5) de- ditional information on prey use, and the influence and fer listing the goshawkunder the ESA in favor of a co- •nteraction of prey abundance, availability,and habitat ordinated national effort to assess habitat conditions, structure on goshawkpopulations, is needed. A multi- monitor populations, and evaluate habitat models and speciesapproach, which includes predators, prey, and silviculturaltreatment experiments (see Marzluff and Sal- competitors,also movesus awayfrom single-speciesman- labanks1998, Squireset al. 1998). Federal and stateland agement and more toward communityand ecosystemap- management agenciesas well as the timber industry proaches (Squireset al. 1998). should be involved in this process.We should keep in mind, however, that listing remains an option and per- DISCUSSION AND CONCLUSIONS haps a necessity,but one that should be basedmore on There is little doubt that we have destroyed,fragment- coordinatedscientific efforts than political agendasfrom ed, and otherwise altered old-growth forest in North either side of the issue.Resource agencies need to make DECEMi3EP, 1998 COMMENTARY 347 firm commitments now to avoid listing the goshawklater. tors: a role for volunteersin wildlife research.J. Wildl. It would also be beneficial to avoid court, where "truth" Manage. 62:435-445. •s not alwaysbased on the best science, but rather the BLOCK, W.M., M.L. MOP,mSON AND M.H. REISE•, [EDS.]. most forceful argument. 1994. The Northern Goshawk:ecology and manage- There is growing dissatisfactionwith single speciesap- ment. Stud. Avian Biol. 16. proachesto conservationand management.We need to BRIGHT-SMITH,DJ. AND R.W. MANNAN.1994. Habitat use pursue research and management at all levels of orga- by breeding male Northern Goshawksin northern Ar- nization: populations,communities, and ecosystems.The izona. Stud. Avian Biol. 16:58-65. goshawkis a good candidatefor this multilevelapproach. CROCKER-BEDFORD,D.C. 1990. Goshawk reproduction However, if we were to base our plans for the conserva- and forest management. Wildl. Soc.Bull. 18:262-269. uon and managementof old-growthforest solelyon the CUTLEa,T.L., RJ. STEIDLAND S. DESTEFANO.1996, Diets goshawk,we may not like what we get. It is true that of Northern Goshawksin Oregon. USDA For. Serv, mature forest is important around nest sites and as a Portland, OR U.S.A. component of foraginghabitat, but ideal goshawkhabitat DAW, S.K. 1997. Northern Goshawk nest site selection may include a sizeableportion of the landscapein early and habitat associationsat the post-fledgingfamily seral stage forest to encourage high populations of im- area scalein Oregon. M.S. thesis,Oregon State Univ, portant prey such as lagomorphs and Ruffed Grouse. Corvallis, OR U.S.A. The distributionof seralstages that may be goodfor gos- , S. DESTEFANOAND RJ. STEIDL.1998. Does search hawks,however, may actuallyinclude lessold-growth than method bias the description of Northern Goshawk some other speciesrequire (possiblyPileated Woodpeck- nest-siteselection? J. Wildl.Manage. 62:1378-1383. ers [Dryocopuspileatus] and American marten [Martes DESIMONE,S.M. 1997. Occupancyrates and habitat rela- americana]). tionships of Northern Goshawksin historic nesting hnplementing the aboverecommendations would take areasin Oregon. M.S. thesis,Oregon State Univ., Cor- our collective will and effort, and it would mean that the vallis, OR U.S.A. land managementagencies most involvedwith goshawks DESTEFANO,S. ANDJ.MCCLOSKEY. 1997. Doesforest struc- would need to be proactiveand support research,adap- ture limit the distribution of Northern Goshawks m t•ve management, and monitoring for more than a few the CoastRanges of Oregon?J. RaptorRes. 31:34-39 years. Terms like "proactive" and "adaptive manage- , B. WOODBRIDGEAND PJ. DETRICH.1994. Survival ment" are often used, but theseconcepts would need to of Northern Goshawks in the southern Cascades of be translated into action on the ground (Marzluff and California. Stud. Avian Biol. 16:133-136. Sallabanks1998). Such actions,of course,will take quite DOYLE,F.I. ANDJ.M.N. SMITH.1994. Population responses a bit of money, but I couldn't agree with Smallwood of Northern Goshawksto the 10-year cycle in num- (1998) more when he states that adequate funding bers of snowshoe hares. Stud. Avian Biol. 16:122-129. should be made availableto ensure the viability of wildlife FORSMAN,E.D., E.C. MESLOW AND H.M. WIGHT. 1984. Dis- populations. tribution and biology of the Spotted Owl in Oregon. Wildl. Monogr87. ACKNOWLEDGMENTS GRAHAM, R.T., R.T. REYNOLDS,M.H. REXSLY,,R.L. BASSETT I thank D.C. Crocker-Bedford, T. Bosakowski, M.H. AND D.A. BOVCE.1994. Sustaining forest habitat for Henning, P.L. Kennedy,J.M. Marzluff, and K.S. Small- the Northern Goshawk:a questionof scale.Stud. Avz- wood for their thoughtful and constructivereviews. My an Biol. 16:12-17. special thanks to D.E. Varland for providing me the op- IVERSON, G.C., G.D. H^VW^RD, K. TITUS, E. DEGAYNER, portunity to air my views. Research on goshawksin R.E. LOWELL, D.C. CROCKER-BEDFORD,P.F. 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