j. RaptorRes. 32 (1) :19-27 ¸ 1998 The Raptor ResearchFoundation, Inc.

CONSERVATION STATUS OF OF PREY IN THE SOUTH AMERICAN TROPICS

RICHARDO. BIERREGAARD,JR. Departmentof Biology,University of North Carolinaat Charlotte,9201 UniversityCity Blvd., Charlotte, NC 28223-9201 U.S.A.

ABSTRACT.--TheICBP/IUCN Red Data Book listsas Threatened or Endangered five of the 82 of and one of the 32 Strigiformes that breed in tropical . The White- collared Kite (Leucopternisforbesi), an endemic of the Atlantic coastalforests of , can be added to this list. Becausevast areas of South America, most notably its tropical forests,have been inadequately surveyedand few studieshave been carried out on raptor speciesor assemblages,our knowledgeof the distribution and natural history of many raptor species,especially owls and forest-dwellingFalconifor- mes, is rudimentary at best. Most needed for conservationpurposes is information on population den- sities,distribution, and reproductivebiology that will tell us how large populations are and how fast they can reproduce. For most species,these data are anecdotal or nonexistent.Although the majority of South America's tropical raptors appear not to be globally threatened at present, more information is needed to confirm current assessments,recognize when speciesbecome threatened, and to move quickly and efficiently to addresssuch threats. KEYWORDS: Falconiformes;Strigiformes; endangered species; habitat loss; South America; tropical forest;, conser- vation.

Estado de conservacionde las avesrapaces en los tropicos de Am6rica del Sur RESUM•N.--E1Libro Rojo de la ICBP/IUCN incluye coxnoamenazadas o en peligro a cinco de las 82 especiesde Falconiformesy una de las 32 Strigiformes que se reproducen en los tr6picos de Aan6rica del Sur. Leucopternisforbesi,endSmica de los bosquescosteros del Atl•tnticoen Brasilpuede ser adicionada a esta lista. Vastasfireas de Sur•unerica,mas especificamentelos bosquestropicales han sido inadecu- adamente investigadosy pocos estudioshan sido realizados sobre las especiesde avesrapaces o sobre susensamblajes, nuestro conocimiento de la distribuci0n e historia natural de muchas especiesde aves rapaces,especiahnente buhos y Falconiformesde bosque,es rudimentario. Para prop6sitosde conser- vaci0n se requiere de informaci6n relacionada con densidadespoblacionales, distribuci6n, biolog•a reproductiva, que pueda decirnos de que tamafio son las poblacionesy que tan r•tpido se pueden reproducir. Para la mayorCade las especiesestos datos son anecd6ticose inexistentes.A pesar de que la mayoria de las avesrapaces de Am6rica del Sur no esfftnglobahnente amenazadasen el presente, se requiere de mas informaci6n para confirmar las evaluacionesactuales y poder reconocer cuando una especiese encuentra en peligro y poder actuar r•tpidamente para en forma eficiente abordar las amen- azas. [Traducci6n de C6sar Mfirquez]

The South American continent is renowned for are found primarily south of the tropicsbut have its avian diversity;roughly 32% (3100 species)of rangesthat extendinto the tropics(north of 30øS). the world's avifauna is found there, on only 12% Not coincidentally, South America is also re- of the world's land surface. Birds of prey are no nowned for its Amazonian rainforests, home to exception. Eighty-fourFalconiformes and 32 Strio many of the continent's remarkable avifauna. giformesare resident in South America (following Among the raptors, 52 Falconiformesand 25 owls the taxonomyin Hume [1991] and de1Hoyo et ai. are associated with some sort of tropical forest, [1994]). These totalsrepresent 28% and 21%, re- from the lowlandsto high-altitude cloud forests. spectively,of the world's speciesin these two or- Tropical forests around the world are being ders. Most (82) of the Falconiformes(Appendix 1) clearedat alarmingrates (Whitmore 1997), with an and all of the owls (Appendix 2) are tropical or inevitable loss of primary habitat and fragmenta-

19 20 BIERREGAARD VOL. 32, NO. 1 tion of what remains. These landscape-wide tion has hardly been studied in the South Ameri- changeshave profound implicationsfor the con- can tropics. Including subspecies,the 82 Falconi- servation of biological diversityand have piqued form speciesin South America representonly 128 the attention of biologistsfrom the conservation strictly South American taxa. Most species are community(e.g., Lauranceand Bierregaard1997). monotypic and four speciesalone account for 22 Although the loss of tropical forests is the most of these taxa (Appendix 1). The constraintof only conspicuousthreat to tropical species,the conver- considering South American forms is clearly arti- sion of wooded or open savannato intensive agri- ficial since many of the speciesoccur in Central culture is also taking its toll by reducing available America, Mexico, and the Caribbean,where many habitat. are representedby variousdistinct populations. In- Birds of prey, as top-order predators with large cluding Central American, Mexican, and Caribbe- home ranges and generally low population densi- an populations,the number of taxa representedby ties, may be especiallysensitive to suchhabitat loss the 82 speciesclimbs from 128 (1.6 taxa/species) and fragmentation. Due to this, certain taxa may to 170 (2.1 taxa/species)(Appendix 1). Hence, the be important indicatorsof habitat integrity.Along much smaller Central American region containsa with their high visibility and general allure, they great deal of biologicaldiversity and is of great con- are ideal "flagshipspecies" for the conservationof servation concern, particularly given the greater critically endangered habitats. annual rate of deforestationthere when compared In this paper, I review the aspectsof the biology to tropical South America (Whitmore 1997). of tropical speciesthat I feel need to be better un- Data on reproductive biology such as behavior, derstoodif we are to assessaccurately their conser- clutch size, frequency of nesting attempts, survi- vation status,and then I briefly summarizethe ar- vorship of nestlings,and recruitment into the adult eas where our knowledge is weakest.Within this population can provide an estimate of a species' framework, I discussthe principal threats to raptor potential rate of population growth. Combined speciesin the South American tropics, review the with estimatesof population size or density,these general trends that are apparent, discussthe status data are important in assessingthe potential resil- of eight speciesthat seem to merit special atten- ience of a population. tion, and make recommendations for future re- Finally, information on each species'habitat re- search. quirementswill also help us to assessthreats to its persistence.Not all speciesthat are typicallyfound DATA NEEDED in any given habitat are behaviorallyor ecologically Effective conservation must be based on a sound restricted to it. A number of North American rap- understanding of a number of biological factors, tors have shown great behavioral plasticityand are principally but not exclusively: distribution and nesting in suburban (e.g., Merlins [Falcocolumbar- population density,, breeding behavior ius; Sodhi et al. 1991], Swainson's [ and reproductive rates, and habitat requirements, swainsoni;England et al. 1995], Cooper's Hawks or, conversely,sensitivity to habitat modification. [Accipitercooperii; Rosenfield et al. 1995]) or urban Information on migratory habits and prey special- (Peregrine [Falco pereg,inus])settings. In ization is important as well. Distribution and pop- Central America, a number of raptorsnest in both ulation density together provide an estimate of primary forest as well as more disturbedlandscape population size,which is crucial in monitoring the mosaics of agriculture, second growth, and pri- vulnerability of a species. mary forest (Whitacre pers. comm.). Although it is not often considered in conser- DATA IN HAND vation discussions,our understanding of taxonomy at the specific and subspecificlevel is indeed im- A recent review (Bierregaard 1995) highlighted portant. In fact, we face many problems in defining the gaps in our knowledge of the natural history biological and phylogeneticspecies and in decid- of the Falconiformes in Meso- and South America. ing how to deal with distinct populations (Zink and Overall, the specieswe know the least about are McKitrick 1995). These questions have conserva- the small residents of primary forest, especially tion implications becauseconservation laws focus those in the genera Accipit• ,and Mi- at only the specieslevel. crastur.Nests have not been described for 16 spe- Among Falconiformes, subspecific differentia- cies (Table 1), and fewer than five nests have been MARCH 1998 RAPTORSIN SOUTH AMERICAN TROPICS 21

Table 1. South American Falconitbrmeswith very poorly known natural histories.

UNKNOWN BREEDING SCANT OR No PREY NEST UNDESCRIBED BIOLOGY DATA a

Leptodonforbesi x x 0 Ha,pagus diodon x + Circusbuffoni + Accipiterpoliogaster x x 0 Accipitersuperdliosus + Accipitercollaris x x 0 Accipiterventmlis x + Accipitereryth,vnemius x x 0 Leucopternisschistacea x x Leucopternisplu mbea x x + Leucopternisprinceps x x + Leucopternismelanops x x + Leucopterniskuhli x x + Leucopternislacernulata x x Leucopternispolionota x x Buteogallussubtilis + Ha,pyhaliaetussolitarius + Harpyhaliaetusco,vnatus Buteoalbigula x + Buteo ventralis x + Phalcoboenus carunculatus x Phalcoboenusmegalopterus x Phalocoboenusalbogularis x + Milvago chimachima x Micrasturplumbeus x x + Micrasturgilvicollis x Micrastur mimndollei x x Micrasturbuckleyi x 0 Spiziapteryxcircumcinctus + a 0 = no prey data available,+ = anecdotaldata only. describedfor an additional 12 species.Breeding of raptor speciesin tropical South American for- behavior is unknown for 20 speciesand is only ests.The majority of what we know about mostrap- anecdotallyknown for an additional18 species(Ta- tors is derived from data that were collected inci- ble 1). No prey data have been reported for five dentallyduring other studies.The discoveryof 38 speciesand only anecdotal data are available for nestsof the Barred Forest-falcon(Micrastur ruffcol- an additional 21 species(Table 1). lis; Thorstrom et al. 1991) stands out as one of the Why do we know so little about somany species? more remarkable studies. Most of the poorly-knownspecies are small, secre- tive inhabitants of dense, continuous forest, where THREATENING FACTORS observationis extremely difficult. Many, such as The loss of primary, native habitats is the most the forestfalcons of the genusMicrastur, are cavity serious threat to the flora and fauna of the world, nestersand rarely seen, and field identification of and raptorsin the tropicsare no exception.The many speciesis not alwayseasy (Howell and Whit- clearingof tropicalrainforests occurred globally at taker 1995). an averagerate of 0.81% per annumover the 1980s Given all these difficulties,it is not surprising and showsno sign of abating (FAO 1993, cited by that with the notable exception of Thiollay'swork Whitmore 1997). Annual deforestation in Central in French Guiana (e.g., Thiollay 1989b) there have America and the Caribbean (0.97%) was substan- been no intensive studies of more than a handful tially above,while that in tropical South America 22 BIERREGAARD VOL. 32, No. 1

(0.71%) was slightlybelow the global decadeav- where they have been hunted by gold miners, erage (FAO 1993, cited by Whitmore 1997). rubber tappers, and indigenous peoples for hun- The tropical forests of South America can be dreds of years (Redford 1992). coarsely divided into four regions: the lowlands OVERALL TRENDS and foothills west of the , which are biogeo- graphically an extension of the Central American Because so little of lowland Amazonia has been forests (or vice versa;Gentry 1990); the higher el- clearcut and most raptor speciesare broadly dis- evation forests of the Andean Cordillera; the Am- tributed acrossthe region, there are no speciesin azon basin; and the Ariantic forests of Brazil, which great peril in this area. In contrast,some species extend south through parts of and Uru- inhabiting the slopesof the Andean Cordillera and guay into northern (Misiones). Brazil's Atlantic coastal forests are more vulnerable Deforestation occurs across these four regions becausethey have more limited ranges and these with variable causes, rates, and extents. It is occur- ecosystemshave been extensivelyclearcut. ring most rapidly in northwesternEcuador and Co- Throughout tropical South America, we can be lombia, acrossa broad front along the northern fairly confident that 53 speciesare not globally and southern fringes of the Amazon basin, and threatened at present. Some speciesare even in- throughout the Atlantic coastalforests of Brazil ap- creasingtheir range as forestsare felled and con- proximately 500 km southeastof Amazonia. Cur- verted to a mosaicof forest fragments,agricultural rently, the extent of deforestation runs from land and second growth. For example, the Black- roughly90% in the Atlantic forests(where defor- chested - (Geranoaetusmelanoleucus; estation began over 300 yr ago) and Ecuador'sPa- Teixeira et al. 1988) and White-tailed (Buteo cific lowlands and foothill forests below 900 m albicaudatus;Pacheco and Whitney 1995) are mov- (Dodsonand Gentry 1991) to roughly6% in Ama- ing northeast into the decimated Atlantic forestsof zonia as of 1988, with 15% of the region affected Brazil. by deforestation,isolation, and edge effects (Skole Del Hoyo et al. (1994) considered11 speciesto and Tucker 1993). be Near Threatened (Appendix 1). Three of these While the conservationof tropical forest is cru- are far too poorly known to make an assessmentof cial, the conversionof open country such as the their status,and the remaining eight are included llanos and cerrado to cattle grazing and intensive primarily becausethey are large (e.g., Harpy and agriculture is also vital due to the detrimental ef- CrestedEagles [Morphnusguianensis] ), rare (Black fects on a broad range of different raptors. Partic- Solitary Eagle [Harpyhaliaetussolitarius]), or have ularly egregious are the large-scalesoybean and restrictedranges (Mantied Hawk [Leucopternispo- sugar cane plantations of eastern and southern lionota]). Brazil. Compounding the problemsassociated with There are insufficient data to adequatelyassess implanting vast expansesof monoculture crops is the statusof at least 14 species.Of these, three are the indiscriminant use of pesticides. considered Near Threatened by del Hoyo et al. Alvarez-Ltpez and Kattan (1995) reviewed the (1994) and 11 are probably Not Threatened (Ap- status of 14 speciesof resident, diurnal birds of pendix 1). prey in the CaucaValley of . Severalspe- As a group, owls are probably less vulnerable cies have declined as expecteddue to reduction in than diurnal birds of prey becausethere are no forest or wetland habitats,but three open-country very large specieswith large home ranges, and speciesunexpectedly declined as well. This may their nocturnal habits make them much less vul- have been due to the effectsof heavycattle grazing nerable to hunting. As with the Falconiformes, and/or pesticideuse. however,special attention should be paid to spe- Hunting by humans is certainly a problem for cies of owls in the Andes and Pacific slope where larger speciesof raptors.The frequencywith which endemic specieswith very restrictedranges occur, radio-tagged Harpy (Harpia harpyja) have as well as those in the Atlantic coastal forests. been shot is an indication of this (E. Alvarez pers. Three species of owls (Black-capped Screech comm.). Thiollay (1989a) has suggestedthat many Owl [ Otusatricapillus], Rusty-barred Owl [ Strixhy- forest speciesmay be sensitiveto what would be lophila]and Tawny-browedOwl [Pulsatrix koeniswal- consideredmild hunting pressure,and already re- diana] ), which are endemic to southern Brazil and duced in the large tracts of unsurveyedrainforest portions of its Atlantic coastal forest, should be MARCH 1998 RAPTORS IN SOUTH AMERICAN TROPICS 23 watched simply becauseof the scaleof habitat loss cause so little is known about possible threats to in this region. We can presume the Black-capped the species,it is consideredonly to be Vulnerable Screech Owl has small enough home range re- and is largely unprotected.It is in need of study. quirements that it should be able to hold out in The Lesser Collared Forest-falcon (Micrastur relatively small remnant forest reserves,while the buckleyi)is a very poorly known speciesrecorded other two speciesare too poorly known to specu- only from a small area in western Amazonia. It is late on their situation. considered rare, but its secretive habits and simi- larity to the sympatricCollared Forest-falcon(M SPECIES OF SPECIAL CONCERN semitorquatus)suggest that the may be more The Andean Condor (Vultur gryphus)is Threat- widespread. Collar et al. (1992) listed the species ened over most of its range (Collar et al. 1992). as insufficientlyknown and in need of further pro- Although it is still common in some areas,it is very tection, concluding, however,that it will probably rare in the northern Andes, where reintroduction prove relativelywidespread and secure. I feel that programs are underway.The speciesis very poorly it is a speciesfor which we have insufficient data known biologically,but apparentlyhas very low re- but which is probably not threatened. A western productive rates and consequentlyis very suscep- Brazilian record for the specieshas been retracted; tible to persecution. the specimenson which this range extension was The recently rediscoveredWhite-collared Kite based are under study and may represent a new (Leucopternisforbesi; Teixeira et al. 1987), consid- taxon (A. Whittaker pers. comm.). ered a valid speciesby del Hoyo et al. (1994), may The Plumbeous Forest-falcon (Micrastur plum- be the most endangered raptor in South America. beus),endemic to the western slope of the Andes While it is not uncommon in its range, the species in Colombia and Ecuador, is Vulnerable, largely is restricted to the extreme northeast of the Arian- unprotected, and is in need of study.The species' tic coastal forests of Brazil, an area undergoing biology is practically unknown, but a study is un- devastatingdeforestation. derway in the Rio Nambi Nature Reserve in south- The White-necked Hawk (Leucopternislacernula- western Colombia with encouraging preliminary ta), another endemic to Atlantic forests of eastern results (P. Salaman pers. comm.). Brazil, is also considered vulnerable/rare, with its The Long-whiskeredOwl (Xenoglauxloweryi) was population only partly protected. A recent report, recently discovered and described at only two lo- however, provided interesting observations on calities on the east slope of the Andean Cordillera. hunting behavior,confirming that the speciesis an It is considered insufficiently known and in need insect specialistthat follows monkeys,army ants, of further protection (Collar et al. 1992). and even lawn mowersto capture flushed insects RESTRICTED TAXA (Martuscelli 1996). Such adaptability to the pres- ence of humans in the environment suggeststhat A number of subspeciesthat are obligate forest the speciesmight persist as long as some habitat dwellerswith rangesoccurring in areasundergoing remains. rapid deforestationare worthy of careful attention. The Gray-backedHawk (Leucopternisoccidentalis) In Central America and the western slope of the is consideredseriously endangered and in need of Andes in Colombia and Ecuador, they are the Or- urgent action. It is endemic west of the Andes in nate Hawk-eagle (Spizaetusornatus vicarius), Barred Ecuador and adjacent northwest Peru, where de- Forest-falcon (Micrastur ruficollis interstes) , and Col- forestation is proceeding rapidly, and it maintains lared Forest-falcon (Micrastur semitorquatusnaso). sizeable populations at only two sites.Recent stud- In the forests of eastern Brazil and into northern ies by Vargas (1995) have substantiallyincreased Argentina, there is also a race of the Black Hawk- our knowledgeand provided specificrecommen- eagle (Spizaetustyrannus tyrannus). A race of the dations for protecting habitats for the species. Barred Forest-falcon (M. r. olrogi) occurs only in The Crowned Solitary Eagle (Harpyhaliaetusco- the dry forestsof northwest Argentina. ronatus)is mostlya bird of subtropicalto temperate NEW RESEARCH regions of South America, but it does extend into tropical zonesin Brazil and Bolivia.Although it has Since my earlier review (Bierregaard 1995), stud- been recorded over a broad geographic range, it ies have documented range expansionsof several apparently occurs at extremely low densities.Be- species.Black Hawk-eaglesand Ornate Hawk-ea- 24 BIERREGAARD VoI•. 32, No. 1 gles,for example,have been recordedin new parts iformes: a surveyof current knowledge.Bird Conserv. of Paraguay(Williams 1995) and in the third larg- Int. 5:325-340. est tract of forest in Brazil's Atlantic forest in Santa COLI•a•, NJ., L.P. GONZ^G^,N. Ka)agBE,A. M•a)RO•40NIE- TO, L.G. N•NJO, T.A. P•KER III, AND D.C. WEGE. Catarina (Serra do Tabuleiro) where Harpy Eagles 1992. Threatened birds of the Americas. Smithsonian were also reported as recently as 1989 (Albuquer- Inst. Press and International Council for Bird Pres- que 1995). The Crested Eagle has been reported ervation, Cambridge, U.K. and Washington, DC in Beni, Bolivia (Pearman 1994) and the Black- U.S.A. and--eagle (Spizasturmelanoleucus) was DELHOYO, J., A. ELLIOT,AND A. SARGATAL[EDS.]. 1994. reported in a new area in Paraguay(Lowen et al. Handbook of birds of the world. Vol. II. New world 1995). The Near Threatened Mantied Hawk has vultures to guineafowl. Lynx Edicions, Barcelona, been discoveredin an important tract of forest in Spain. southeasternBrazil (Forrester 1993, cited by Gon- DODSON,C.H. ANDA.H. GENTRY.1991. Biologicalextinc- tions in western Ecuadon Ann. MO Bot. Gard. 78:273- zaga et al. 1995). 295. In Venezuela,30 breeding pairs of Harpy Eagles ENGL•tND,A.S., J.A. ESTEPAND W.R. HOLT. 1995. Nest- have been located (Anonymous1996, and E. Al- site selectionand reproductiveperformance of urban- varez pers. comm.). Preliminary results indicate nestingSwainson's Hawks in the CentralValley of Cal- that nests are much closer than would have been ifornia.J. RaptorRes. 29:179-186. predicted by previous estimatesof density and FAD. 1993. Forest resourcesassessment 1990. Tropical home range (Thiollay 1989a). Important data are countries.FA O ForestryPaper 112. being collectedon local movementof juvenilesin- FORRESTER,B.C. 1993. Birding Brazil: a check-listand strumented with satellite radiotransmitters. Two site guide.John Geddes,Irvine, CA U.S.A. important studieson the Gray-backedHawk and GENTRY,A.H. [ED.]. 1990. Four neDtropical rainforests. PlumbeDusForest-falcon (Vargas 1995, and P. Sal- Yale Univ. Press, New Haven, CT U.S.A. aman pers. comm.), specieswhose biology was pre- GONZAGA,L.P., J.E PACHECO,C. BAUERAND G.D.A. C^S- TIGLIONI.1995. An avifaunal surveyof the vanishing viouslyvirtually unknown (Bierregaard1995), are montane Atlantic forest of southern Bahia, Brazil. Bird providing data needed to monitor tropical raptors Conserv. Int. 5:279-290. and designeffective conservation action plans. HOWELL, S.N.G. AND t. WHITTAKER. 1995. Field identi- fication of Orange-breastedand Bat . Cotinga FUTURE DIRECTIONS 4:36-43. Almost any information about any NeDtropical HUME, R. 1991. Owls of the world. Running Press,Phil- raptor,especially forest species, is useful.Studies of adelphia, PA U.S.A. endemic speciesor subspeciesin the Atlantic for- EAURANCE,W.E ANDR.O. BIERREGAARD,JR. [EDS.]. 1997 estsof Brazil are certainly of a very high priority. Tropical forest remnants:the ecology,management, and conservationof fragmented communities. Univ. Similarly,raptor researchin the Andes or Choc6 ChicagoPress, Chicago, IL U.S.A. region of Colombia and adjacentEcuador could LOWEN,J.C., R.P. CLAY,T.M. BROOKS,E.Z. ESQUIVEL,L. providea significantamount of information.In the B•tTmN^, R. B•ES, S.H.M. BUTCHART AND N.I. central Amazonian lowlands,studies of any species ETCHEVERRY. 1995. Bird conservation in the Para- in the genera Leucopternis,Acdpitg or Micrasturare guayanAtlantic forest. Cotinga4:58-64. important. MA•TUSCELLI,P. 1996. Hunting behaviour of the Man- tied Hawk Leucopternispolionota and the White-necked LITERATURE CITED Hawk L. lacernulata in southeastern Brazil. Bull. Brit ALBUQUERQUE,J.L.B. 1995. Observationsof rare raptors Ornithol. Club 116:114-116. in southern Atlantic rainforest of Brazil.J. Field Orni- P^CHECO,J.F. AND B.M. WHITNEY. 1995. Range exten- thol. 66:363-369. sions for some birds in northeastern Brazil. Bull. Brit. ALV^REz-LtpEZ, H. AND G.H. KATTAN. 1995. Notes on the Ornithol. Club 115:157-163. conservationstatus of resident diurnal raptors of the PE)mMAN,M. 1994. NeDtropicalnotebook. Cotinga1:26- middle Cauca Valley, Colombia. Bird Conserv.Int. 5: 29. 341-348. R•DFOm),K. 1992. The empty forest. BiDScience42:412- ANONYMOUS.1996. Harpy Eagle conservationprogram. 422. The Peregrine Fund 1995 Annual Report. The Pere- ROSENFIELD,R.N., J. BIELEFELDT,J.L. AFFELDTAND DJ. grine Fund, Inc., Boise,ID U.S.A. BECk. 1995. Nesting density,nest area reoccupan- BIERREGAARD,R.O., JR. 1995. The biology and conser- cy, and monitoringimplications for Cooper'sHawks vation status of Central and South American Falcon- in Wisconsin.J. RaptorRes. 29:1-4. MARCH 1998 RAPTORS IN SOUTH AMERICAN TROPICS 25

SKOLE,D.L. ANDCJ. TUCKER.1993. Tropical deforesta- tacre, W.A. Burnham and J.P.Jenny lEDS.I, Maya Pro- tion and habitat fragmentationin the Amazon:satel- ject: using raptors and other fauna as environmental lite data from 1978 to 1988. Sdence 260:1905-1910. indicators for design and management of protected SOr)H•, N.S., I.G. WARKENTINAND L.W. OLIPHANT. 1991. areas and for building local capacityfor conservation Hunting techniquesand successrates of urban Mer- in . The Peregrine Fund, Inc., Boise,ID lins (Falco columbarius) . J. RaptorRes. 25:127-131. U.S.A. TEIXEIRA,D.M., J.B. NACINOVICAND F.B. PONTUAL.1987. VARGAS,H. 1995. Food habits, breeding biology,and sta- Sobre a redescobertade Leptodonforbesi(Swann, 1922) tus of the Gray-backedHawk (Leucopternisoccidentahs) no nordeste do Brasil.Abstracts X/V CongressoBrasileiro in western Ecuador. M.S. thesis, Boise State Univ., Boi- de Zoologiain Juiz deFora, Brasil. 148. se, ID U.S.A. •, J.B. NACINOVICAND G. LUIGI. 1988. Notes on WHITMORE,T.C. 1997. Tropical forest disturbance,d•s- some birds of northeastern Brazil (3). Bull. Brit. Or- appearance, and speciesloss. In W.F. Laurance and nithol. Club 108:75-79. R.O. Bierregaard,Jr. lEDS.],Tropical forestremnants. ecology,management, and conservationof fragment- THIOLLAY,J.-M. 1989a. Area requirementsfor the con- ed communities. Univ. Chicago Press, Chicago, IL servation of rainforest raptors and game birds in U.S.A. French Guiana. Conserv. Biol. 3:128-137. WILLIAMS,R. 1995. Neotropical notebook. Cotinga4:65- 1989b. Censusingof diurnal raptors in a pri- 68. mary rainforest:comparative methods and speciesde- ZINK, R.M. AND M.C. MCK•TRICK. 1995. The debate over tectability.J. RaptorRes. 23:72-84. speciesconcepts and its implications for ornithology. THORSTROM,R.K., A.M. QUIXCHANAND C.M. MORALES. Auk 112: 701-719. 1991. Breeding biology of the Barred (Micrasturruficollis). 1991. Pages121-126 in D.E Whi- Received16 October 1996; accepted8 October 1997 26 BIERREGAARD VOL. 32, NO. 1

Appendix 1. Number of Falconiform taxa in Meso- Appendix 1. Continued. Aanerica and Tropical South America.

MESO- TROP- MESO- TROP- WORLD- A-MER- ICAL WORLD- A_MER- ICAL WIDE ICAN S.A. WIDE ICAN S.A. SPECIES TAXA TAXA TAXA SPECIES TAXA TAXA TAXA Buteo nitidus 4 CATHARTIDAE Buteomagnirostris 12 Cathartes aura 4 1 2 Buteo leucorrhous 1 Cathartes burrovianus 2 2 2 Buteobrachyurus 2 Cathartes melambrotus I 1 Buteoalbigula 1 Coragypsatratus 3 I 2 Buteo albicaudatus 3 Sarcoramphuspapa 1 1 Buteogalapagoensis 1 Vultur g,ryphus 1 1 Buteopolyosoma 2 Buteopoecilochrous 1 Buteo albonotatus 1 Leptodoncayanensis 2 2 Morphnusguianensis 1 Leptodonforbesi 1 1 Harpia harpyja 1 Chondrohierax uncinatus 3 2 1 Spizasturmelanoleucus 1 Elanoidesforficatus 2 1 1 Spizaetustyrannus 2 Gampsonyxswainsonii 3 3 Spizaetusornatus 2 Elanus leucurus 2 I 1 Oroaetus isidori 1 Rostrhamus sociabilis 3 2 1 Rostrhamus hamatus 1 1 Harpagusbidentatus 2 2 Daptrius ater 1 1 Harpagusdiodon 1 1 Daptrius americanus 1 1 Ictinia plumbea I 1 Phalcoboenus carunculatus 1 1 Circusbuffoni 1 1 Phalcoboenusmegalopterus 1 1 Circus cinereus 1 1 ( Polyborus)plancus 4 2 2 A ccipiterpoliogaster 1 1 Milvago chimachima 2 2 Accipitersuperciliosus 2 2 Milvago chimango 2 1 Accipitercollaris 1 1 Herpetotherescachinnans 3 1 2 A ccipiterventralis I 1 Micrasturruficollis 6 1 5 Accipitererythronemius 1 1 Micrasturplumbeus 1 1 Acdpiterbicolor 4 1 3 Micrasturgilvicollis 1 1 Geranospizacaerulescens 6 2 4 Micrastur mirandollei 1 1 Leucopternisplumbea I 1 Micrastursemitorquatus 2 2 Leucopternisschistacea I 1 Micrastur buckleyi 1 1 Leucopternisprinceps 1 1 Spiziapteryxdrcumcinctus 1 1 Leucopternismelanops 1 1 Palcosparverius 17 8 7 Leucopterniskuhli 1 1 Falcofemoralis 3 1 2 Leucopternislacernulata I 1 Falcorufigularis 3 3 Leucopternissemiplumbea I 1 Falco deiroleucus 1 1 Leucopternisalbicollis 4 1 3 Fatcoperegrinus 19 1 1 Leucopternisoccidentalis 1 1 82 species,total taxa: 190 42 128 Leucopternispolionota 1 1 Taxa/species Buteogallusaequinoctialis I 1 (tropical S.A. only) 1.6 Buteogallusanthracinus 3 2 1 Taxa/species Buteogallussubtilis 3 2 1 (tropical M-A. & S.A.) 2.1 Buteogallusurubitinga 2 I 1 Buteogallusmeridionalis I 1 unicinctus 2 2 Busarellusnig'ricollis 2 2 melanoleucus 2 2 Harpyhaliaetussolitarius 2 I 1 Harpyhaliaetuscoronatus I I IV[ARCH 1998 RAPTORS IN SOUTH AMERICAN TROPICS

Appendix 2. Number of Strigiformesin Meso-America and Tropical South America.

MESa- TRAP- WORLD- AMER- ICAL WIDE ICAN S.A. SPECIES TAXA TArA TAXA

TYTONIDAE Tytoalba 35 9 5 STRIGIDAE Otus albogularis 3 3 Otus atricapillus 3 3 Otus choliba 17 16 Otus colombianus 1 1 Otusguatemalae 17 10 7 Otus ingens 3 3 Otus koepckeae I 1 Otus marshalii 1 1 Otuspetersoni 1 1 Otus roboratus 1 1 Otus watsonii 6 6 Lophostrixcristata 3 2 1 Bubovirginianus 17 3 6 Pulsatrix koeniswaldiana 1 1 Pulsatrix melanota 2 2 Pulsatrixperspicillata 6 2 4 Glaucidium brasilianum 12 2 9 Glaucidiumhardyi 1 1 Glaucidiumjardinii 2 1 1 Glaucidium minutissimum 8 7 1 Glaucidiumperuanum 1 1 Xenoglauxloweryi 1 1 Speotytocunicularia 19 5 12 Ciccaba albitarsus 2 2 Ciccaba huhula 1 1 Ciccabanigrolineata 1 1 Ciccabavirgata 8 3 5 Strix hylophila 1 1 Strix rufipes 3 1 Rhinopteryxdamator 3 3 Asioflammeus 10 2 4 Asiostygius 6 4 2 Aegoliusharrisii 3 3 34 species,total taxa: 200 53 108 Taxa/species (tropical S.A. only) 3.2 Taxa/species (tropical M-A. and S.A.) 4.7