The Condor94~29-39 0 The Cooper Ornithological Society 1992
ALTITUDINAL DISTRIBUTION OF BIRDS IN THE SIERRA MADRE DEL SUR, GUERRERO, MEXICO’
ADOLFO G. NAVARRO S. Muse0 de Zoologia “Alfonso L. Herrera,” Department0 de Biologia, Facultad de Ciencias, UniversidadNational Autbnoma de Mexico, Apartado Postal 70-399, Mt?xicoD.F. 04510, Mxico
Abstract. Altitudinal patterns of distribution, diversity, and speciesturnover in the avi- fauna of the Sierra de Atoyac, Sierra Madre de1Sur, Guerrero, Mexico, were studied along a transectfrom the tropical coastalplain to high-altitude coniferousforests. Species richness is highest at low elevations and declines with increasing altitude. Richness is relatively uniform within habitat types,but high levels of speciesturnover are found at habitat ecotones. Altitudinal rangesof congenerspecies pairs overlap more frequently than predicted by null models, suggestingthat competition may not have played a dominant role in structuring the community. Patterns of diversity, endemism, and habitat destruction are discussedin terms of conservation priorities. Key words: Altitudinal distribution;Guerrero; Mkxico; speciesturnover; competition; con- servation.
Resumen. Se estudiaron 10spatrones de distribution altitudinal, diversidad y recambio de especiesde la avifauna residente en la Sierra de Atoyac, Guerrero, Mexico, a lo largo de un transect0 altitudinal que abarca todos 10stipos de vegetation presentes,desde la vege- tacion costerahasta 10sbosques altos de coniferas. La riqueza de especieses mayor en las partesbajas, decreciendo conforme aumenta la altitud. La riqueza es notablementeconstante dentro de 10s habitats, pero altos niveles de recambio de especies se encuentran en 10s ecotonos. Los intervalos altitudinales que ocupan pares y trios de especiescongenericas muestranun mayor solapamientoque el predicho por modelosestadisticos nulos, sugiriendo que la competencia no ha jugado un papel dominante en la estructuracionde las comuni- dades. Los patronesde diversidad, endemism0 y 10sefectos de la destruction de 10shabitats son discutidos en ttrminos de prioridades de conservation. Palabras clave: Distribucih altitudinal; Guerrero;Mgxico; recambiode especies;com- petencia;conservacidn.
INTRODUCTION tudinal patterns in the avifauna of the Sierra Ma- Analysis of altitudinal changes in diversity, dre de1 Sur, Guerrero, Mexico, in an attempt to abundance, and species composition of biotas understand the relative importance of thesethree can provide important information on such phe- factorsin structuring the community. The degree nomena as aspectsof the environment limiting to which habitat boundaries and competition in- the distribution of organisms, factorsinfluencing troduce structure into the community is statis- the structure of communities, and aspectsof bio- tically analyzed and variation not explained by geography.A theoretical framework by which to those two factorsis attributed to gradual changes understand altitudinal distributions of commu- in environmental parameters (Terborgh 197 1). nities was described by Terborgh (1971, 1977) Although the avifauna of the Sierra Madre de1 and Terborgh and Weske (1975). These authors Sur of Guerrero has been studied since the late arguedthat the three principal factorsinfluencing nineteenth century (Salvin and Godman 1879- altitudinal structuring of communities are abrupt 1904; Nelson 1903; Griscom 1934,1937; Martin changesin habitats, gradual changesin environ- de1 Campo 1948; Blake 1950; Goldman 195 l), mental parameters, and competition. little is known about the composition of the avi- The purpose of this study is to analyze alti- fauna of the humid coastal slope. Moreover, no information exists on altitudinal patterns of avi- an distribution for the region as a whole. Hence, ’ Received 22 January 1991. Accepted 9 October a secondpurpose of this study is to provide base- 1991. line data on the distribution and ecologicalchar-
1291 30 ADOLF0 G. NAVARRO S.
TLACOTEPEC
. PUERTO EL GALL0
0 CHILPANCMGO
dirt roads I m I paved roads 1 FIGURE 1. Geographiclocation of the studyarea: (a) Stateof Guerrero;(b) Sierrade Atoyac. acteristics of the avifauna of the Sierra Madre Ocean. Thus, the Pacific slopesare generally hu- de1 Sur. mid, whereas the interior slopes are xeric. This study was conducted along an altitudinal transect STUDY AREA AND METHODS between the city of Atoyac de Alvarez and the The Sierra de Atoyac lies at the southwestern peak of the highestmountain in the Sierra Madre end of the Sierra Madre de1 Sur, which extends de1 Sur, Cerro Teotepec (Fig. 1). (The higher lo- from western Guerrero east to south-central Oa- calities on this transect have been often referred xaca. The Sierra Madre de1 Sur consists largely to as “Mount Teotepec” or just “Teotepec” in of igneous and metamorphic rocks and appar- the literature.) Eleven stations were established ently arose in the Precambrian independently in primary habitats, each separated by approx- from other mountain massesto the north (Lopez- imately 200 m of altitude (from 620 to 3,100 m; Ramos 1983). Climatically, the region is largely Table 1). These stations span the range of hab- influenced by weather systems from the Pacific itats along the transect (Fig. 2), including semi- ALTITUDINAL DISTRIBUTION OF BIRDS 3 1
altitude (m )
FIR FOREST ------__-- --_----_-----______
PINE-OAK FOREST
2500
2000
1500
1200 -__------__-----_---__-_--
1000 SEMIDECIDUOUS
TROPICAL FOREST
60C FIGURE 2. Vegetation profile of the humid slopeof the Sierra de Atoyac. Broken lines indicate the approximate location of the ecotones. deciduous tropical forest, cloud forest, pine-oak site, with field time distributed in ten of the forest and high-altitude fir forest (see descrip- months of the year. At each site, lines of mist- tions in Table 1). nets were set in each habitat, and experienced A total of 90 days was spent working along the observers made additional observations. Vouch- study transect between March 1983 and May er specimens were obtained for as many species 1985, supplemented by occasional visits during as possible, using both mist-nets and a shotgun. 1989. Between 4 and 16 days were spent at each These are deposited in the Museo de Zoologia,
TABLE 1. Sampling stations along the altitudinal gradient in the Sierra de Atoyac, Guerrero.
Locality Altitude (m) Habitat
1. Rio Santiago, 14 km SW Paraiso 680 SemideciduousTropical Forest 2. Puente Lugardo, 3.5 km W Paraiso 820 SemideciduousTropical Forest 3. El Faisanal, 7.5 km NNE Paraiso 1,200 Ecotone Cloud-SemideciduousForest 4. Nueva Delhi, 8.5 km NNE Paraiso 1,400 Cloud Forest 5. Retrocesos,5.5 km S Puerto El Gallo 1,600 Cloud Forest 6. La Golondrina, 13 km NNE Paraiso 1,800 Cloud Forest 7. El Descanso, 2 km SW Puerto El Gallo 2,000 Cloud Forest 8. El Iris, 3 km NE Puerto El Gallo 2,200 Cloud-Pine-Oak Forest 9. Puerto El Gallo, 15.5 km NNE Paraiso 2,500 Pine-Oak-Cloud Forest 10. Toro Muerto, 10 km NW Puerto El Gallo 2,600 Pine-Oak Forest 11. Teotepec, 4 km E Puerto El Gallo 3,100 Fir Forest 32 ADOLF0 G. NAVARRO S.
60 ;
RS PL EF ND RE LG BL El PG TM TE
statbns
~ linear regression
FIGURE 3. Resident speciesrichness along the altitudinal transect.
Facultad de Ciencias, Universidad National Au- titudinal distributions were assumed to be con- tonoma de Mexico. tinuous, with gapsfilled as describedabove, and, Cumulative plots of resident speciesvs. field for the purposes of this test, altitudinal range days were inspected to assurethat field effort at width was assumed to be insensitive of the pres- each site was sufficient to understand the com- ence of other species(see Discussion). Two def- position of the avifauna of that site. Eight of 11 initions of “non-overlap” were used: (1) com- of these plots were asymptotic by the final day pletely exclusive distributions, in which the of field work, indicating that few species re- congener speciespair never occurred at the same mained undiscovered. When gaps were present station, and (2) adjacent distributions, in which in a species’ altitudinal distribution, we assumed overlap at one station that constitutes an alti- that these representedinadequate sampling, and tudinal limit for both specieswas counted as non- not actual gaps, and thus used adjusted species overlap. Under both overlap definitions, prob- lists for each locality in the analyses that follow. abilities of distributional overlap were calculated In addition, these analysesdo not include highly for all possible combinations of altitudinal range aerial species (e.g., Apodidae, certain Falconi- widths of two species(i.e., one to eleven stations) formes) and speciesof uncertain seasonal status of speciespairs. For the eight congenerpairs and in the area (e.g., Selasphorusplatycercus, Pheuc- six congener trios resident in the Sierra de Ato- ticus melanocephalus, Caprimulgus vociferus). yac, predicted overlap frequencies were calcu- Because it was difficult to distinguish seasonal lated as the weighted mean probability of overlap movements from actual residency of several un- over all possible congener species-pairs.Overlap common species, altitudinal ranges may have probabilities were weighted by devaluing prob- been overestimated for some species.(Complete abilities from congener trios so that each genus avifaunal information is given in Navarro [ 19861 contributed equally to the overall mean. Actual and Navarro et al. [in prep.].) Altitudinal pat- overlap frequencies(also a mean weighted so that terns of species turnover were summarized in each genus contributed equally) were compared two ways: (1) the proportion of speciespresent to the predicted frequencies using a one-sample, at one station reaching their upper or lower al- one-tailed Student’s t-test. This test is conser- titudinal limit before the next station above or vative because the assumption of continuity of below, and (2) using the decay curves of species altitudinal distributions leads to higher levels of presence in successivelymore distant sites pro- overlap than were actually observed. posed by Terborgh (197 1). To test whether com- petition among resident congenersis a dominant RESULTS factor in limiting altitudinal distributions, we A total of 162 species was recorded along the made the following two tests for non-random- transect in this study (Appendix). (Additional nessof altitudinal distributions of congeners.Al- speciesare reported for the region by Friedmann ALTITUDINAL DISTRIBUTION OF BIRDS 33
_ total --t lower limit + upper limit FIGURE 4. Patternsofaltitudinal limits in the studytransect. Letters indicate areasseparating adjacent stations in the altitudinal sequence(ascending).
et al. [ 19501 and Miller et al. [ 19571, but due to limit of coffee cultivation, and seemingly sensi- ambiguity in locality descriptionsit is impossible tive species such as Aphelocoma unicolor and to know whether these records are from the hu- Cyanolyca mirabilis are limited to the better- mid Pacific slopesincluded in this study.) Of the preserved forests at higher altitudes. The latter speciesrecorded during this study, 3 1 (19.13%) correspondsto the lower limit of pine-oak forest, are migrants or vagrants; the remaining 131 at which point many of the high-elevation spe- (80.86%) are assumed to be resident based on cies drop out (e.g., Strix varia, Picoides villosus, presence during reproductive season, observa- Empidonax afinis, and Cyanocitta stelleri). The tions of reproductive behavior, and information decay-curve approach of Terborgh (197 1; Fig. 5) from the literature. shows for the most part the same patterns, al- Species richness of residents declined signifi- though the turnover between stations eight and cantly with altitude (Fig. 3; R2 = 0.65, P < nine is less obvious, and that between stations 0.005 1). Richness was greatestat the two lowest nine and ten is quite marked. stations, lower and more or less constant at the Patterns of altitudinal replacement by closely succeeding nine, and lowest at the highest sta- related species suggestthat competitive inter- tion. actionsmay limit altitudinal distributions in some Semideciduous tropical forest held more res- groups (Terborgh and Weske 1975). For exam- ident species(53-57) than higher elevation hab- ple, in the six speciesof jays that occur in the itats. Speciesrichness in cloud forest (38-44) and area, Cyanocorax sanblasianus is found exclu- humid pine-oak forest (37-43) was remarkably sively on the coastal plain in low scrub and man- constant through 1,350 m of altitude, but was groves,Calocitta formosa rangesfrom the coastal considerably reduced in the high altitude fir for- scrub up to the second station on the transect, est (14). where it is replaced by Cyanocorax yncas. At the Both lower and upper range limits are concen- sixth station, two speciesof cloud forest jays (A. trated between the secondand third stations (as- unicolor and C. mirabilis) are present; C. yncas cending) along the transect (Fig. 4) coincident reachesits upper limit at the seventh station; the with a drastic change in habitats (from semide- two cloud forest jays drop out at the eighth and ciduous tropical forest to cloud forest). Upper ninth stations,respectively; and C. stelleriis found range limits were reached with increasing fre- from the ninth station to the peak of Cerro Teo- quency ascendingthe transect. Lower range lim- tepee. Similar patterns of altitudinal replacement its showed two peaks: one between stations five are found in the genera Empidonax and Basi- and six, and the other between stations eight and leuterus,among others. nine. The former peak correspondsto the upper However, more general tests for non-random- 34 ADOLF0 G. NAVARRO S.
,% I RS PR EF ND RE LG BL EI PG TM TE stations FIGURE 5. Fauna1congruence curves for residentspecies along the altitudinal transect(Terborgh 1971).
ness of altitudinal distributions of resident con- tone, speciesturnover was as high as 30%. There- gener speciesdo not indicate that abrupt replace- fore, a strong influence of habitats on species ments are the rule in the avifauna of the study distributions is indicated. The tests for non-ran- tract. If competition among congeners acts to domness of congener distributions suggestthat structurethe avifauna, observedlevels of overlap competition has not led to a preponderance of should be lower than those predicted by random non-overlapping altitudinal distributions. How- assortment of species’ altitudinal ranges. For the ever, these testsassume that competition has not eight resident congener pairs and six congener influenced altitudinal range amplitudes. If the trios found along the study transect, random as- altitudinal distributions used in constructing the sortment of altitudinal rangespredicts that 56.5% null distributions were themselves affected by of congeneric species pairs should show com- competition, these tests are more likely to fail to pletely exclusive altitudinal distributions, and reject the null hypothesis of no competitive in- 43.1% should show adjacent or non-overlapping teractions.Thus, further analysesof this type must altitudinal distributions. Observed levels of await more detailed information on altitudinal overlap were 6 1.8% (exclusive distributions) and distributions of each speciesin areas lacking its 44.1% (adjacent distributions), actually higher congener species. than predicted levels, and hence levels of overlap Although these tests are restricted to congener were not significantly lower than predicted at species,it is likely that they underestimate the random (P > 0.5, in both cases). effectsof competition becauseseveral of the gen- era include specieswith divergent habitat use and DISCUSSION foraging behavior that are unlikely to compete. Three speciesencountered in this study had not To evaluate this possibility, I considered only been recorded previously for the state of Guer- those genera in which the speciesare found in rero, and hence represent range extensions: the same habitat using the same general foraging Rhynchocyclus brevirostris, Sittasomus grisei- modes (i.e., Amazilia, Trogon, Thryothorus, Pi- capillus, and Basileuterus culicivorus. Distribu- ranga, Saltator). In these genera, where species tional and taxonomic implications of these rec- are ecologically similar, reducedaltitudinal over- ords are discussedelsewhere (Navarro et al., in lap would be expected. However, four of the five prep.). The effectsof habitat on the distribution genera show complete altitudinal overlap, and it of the avifauna are striking. Along the transect, appears that the conclusion of low importance zones of high speciesturnover are largely coin- of competition is not simply a function of the cident with ecotones among habitats. Between diverse array of genera analyzed. adjacent stations located on either side of an eco- In general, however, given the striking species ALTITUDINAL DISTRIBUTION OF BIRDS 35 turnover between and uniformity within habitat in determining altitudinal structure of animal types, it appears that the most important factor communities (Fuentes and Jaksic 1980; Graham in structuring the avifauna of the Sierra de Ato- 1983; Lawton et al. 1987; M. Torres, in prep.). yac is the zonation of habitats. In the analyses Considering the patterns of distribution and presented here, competition among closely re- abundance encountered in this study, it is desir- lated speciesappears not to have had a strong able to identify particular zones or habitats as effect on the distribution of the avifauna, as was conservation priorities. In this particular region, found in Peru by Terborgh and Weske (1975) however, it appears that all of the zones are in although this conclusion is contingent on a re- danger of complete destruction and also contain strictive assumption. Environmental factorsthat unique avifaunal elements. The semideciduous changegradually along the transectprobably also tropical forest at the base of the range contains have an effect, but the importance of this set of the only known populations of the Short-crested factors is difficult to distinguish due to intercor- coquette Lophornis brachylopha (Omelas 1987, relation with habitat types. Banks 1990) as well as the highest species di- Although sample points were located in the versity in the transect. This forest, however, is least disturbed vegetation available, modifica- rapidly being cleared for cultivation of corn, fruit, tion of the habitat by humans also appears to and coffee. The cloud forest zone contains two play a role in structuring avian altitudinal dis- endemic species (the hummingbird Eupherusa tributions in the Sierra Madre de1Sur. A number poliocerca and the jay C. mirabilis) as well as a of species seem completely restricted to undis- number of well-marked geographicdifferentiates turbed habitats. Examples include the jays A. (e.g., Geotrygon albifacies rubida, Dendrortyx unicolor and C. mirabilis, the wood-partridge macroura striatus, Aulacorhynchus prasinus Dendrortyx macroura, and the nightingale-thrush wagleri, Automolus rubiginosus guerrerensis). Catharusfrantzii. The altitudinal ranges of spe- Cloud forests below 1,800 m in this area are cies such as these have certainly changed as hu- almost completely under cultivation for coffee, mans have modified the habitats in the region. with undisturbed forest existing only on the most Terborgh (197 1) and Terborgh and Weske vertical slopes.The higher altitude forestsof pine, (1975) suggesteda series of analyses designed to oak, and fir, although having lower species di- understand the roles of competition, physical versities, contain a number of endemic forms factors,and ecotonesin altitudinal structuring of (e.g., C. mirabilis, Cyanocitta stelleri teotepecen- communities. I have employed some of their ap- sis, Cathurus frantzii omiltemensis). These for- proaches in the analyses of the effect of habitat estsare being cut for lumber at an alarming rate. changes on avian communities; unfortunately, Thus, to the extent that the flora and fauna of their tests of the role of competition are based the Sierra Madre de1Sur are a conservation pri- on population densities, data unavailable in the ority, all altitudinal zones must be represented present study. Further analyses of these types, in an attempt to preserve this area. and especially comparisons among transects (Terborgh and Weske 1975) will be possibleonly ACKNOWLEDGMENTS when more detailed studiesin other localities are Patricia Escalantecollaborated extensively in most of completed (M. Tort-es, in prep.). the field work, as well as with useful comments; her The influence of competition on the altitudinal support and assistancewere invaluable. A. Townsend Petersonkindly reviewed the manuscriptseveral times; distribution of organismshas been tested a num- his suggestionsand assistancewith translation im- ber of times by other authors. Several authors proved this work enormously. Julio Juarez, Teresa Ji- argue that competition is the main factor influ- menez, Armando Luis, Jorge Llorente, Mario Lerma, encing altitudinal ranges, for example in closely JoseJuan Perez, Laura and Fernando Villaseiior, Luis and Mauricio Navarro, Alfred0 Garza, A. T. Peterson, related species in the genus Catharus (Noon D. Scott Baker, Hesiquio Benitez, Not Vargas, Miriam 198 l), and in the structuring of bird communi- Torres and SusanaRivas provided helpful assistance ties in the Andes (Terborgh 1985). Other studies at the field work. Thanks to John Terborgh, Allan R. have shown that physical environmental factors Phillips, Charles A. Ely, JorgeE. Llorente, Livia Leon, that vary with altitude limit their altitudinal Hesiquio Benitez, Oscar Flores-Villela, and especially J. Van Remsen for comments on different drafts of the ranges (Berven 1982, Lawton et al. 1987, Zam- manuscript. Financial supportfor this project was pro- muto and Milliard 1985). However, most studies vided by the Facultad de Ciencias, Universidad Na- have stressedthe importance of habitat structure cional Autonoma de Mexico and the Direction Ge- 36 ADOLF0 G. NAVARRO S. neral de Asuntos de1Personal Acadtmico, project IN- MILLER, A. H., H. FRIEDMANN,L. GRISCOM,AND R. 201780. T. MOORE: 1957. Distributional check-list of the birds of MCxico. Part II. Pacific Coast Avifauna LITERATURE CITED 33:1-436. NAVARROS., A. G. 1986. Distribucibn altitudinal de BANKS,R. C. 1990. Taxonomic statusofthe coquette las aves en la Sierra de Atoyac, Guerrero. Unpubl. hummingbird of Guerrero, MCxico. Auk 107:19 l- BachelorThesis, Facultad de Ciencias,Univ. Nat. 192. Aut6n. MCxico. BERVEN,K. A. 1982. The genetic basis of altitudinal NELSON,E. W. 1903. Descriptions of new birds from variation in the wood frog Rana sylvutica. I. An southern Mexico. Proc. Biol. Sot. Wash. 16:15 l- experimental analysis of life history traits. Evo- 160. lution 36:962-983. NOON,B. R. 1981. The distribution of an avian guild BLAKE,E. R. 1950. A report on a collection of birds along a temperate elevational gradient: the im- from Guerrero, Mexico. Fieldiana Zool. 31:373- portance and expression of competition. Ecol. 392. Monogr. 51:105-124. FRIEDMANN,H., L. GRISCOM,AND R. T. MOORE. 1950. ORNELAS,J. F. 1987. Rediscovery of the Rufous- Distributional check-list of the birds of Mexico, crested Coquette (Lophornis deluttrei brachylo- Part I. Pacific Coast Avifauna 29: l-202. phu) in Guerrero, MCxico. Wilson Bull. 99: 119- FUENTES,E. R., AND F. M. JAKSIC. 1980. Ecological 121. speciesreplacement of Lioluemuslizards along an SALVIN,O., ANDF. D. GODMAN. 1879-1904. Biologia habitat gradient. Oecologia (Berl.) 46:4548. Centrali-Americana. Aves. Taylor and Francis, GOLDMAN,E. A. 1951. Biological investigations in London. Mexico. Smithsonian Misc. Colls. 115:l-476. TERBORGH,J. 1971. Distribution on environmental GRAHAM,G. L. 1983. Changesin bat speciesdiversity gradients:theory and a preliminary interpretation along an elevational gradient up the Peruvian An- of distributional patterns in the avifauna of the des. J. Mamm. 64:559-571. Cordillera Vilcabamba, Peru. Ecology 52:23-40. GRISCOM,L. 1934. The ornithology of Guerrero, TERBORGH,J. 1977. Bird speciesdiversity on an An- Mexico. Bull. Mus. Como. Zool. 75:367-422. dean elevational gradient. Ecology 58: 1007-1019. GRISCOM,L. 1937. A collectibn ofbirds from Omilte- TERBORGH,J. 1985. The role of ecotonesin the dis- me, Guerrero. Auk 54:192-199. tribution ofAndean birds. Ecology66: 1237-1246. LAWTON,J. H., M. MACGARVIN, AND P. A. HEADS. TERBORGH,J., AND J. S. WESKE. 1975. The role of 1987. Effects of altitude on the abundance and competition in the distribution of Andean birds. speciesrichness of insect herbivores on bracken. Ecology 56~562-576. J. Anim. Ecol. 56:147-160. ZAMMUTO,R. M., ANDJ. S. MILLARD. 1985. Environ- LOPEZ-RAMOS,E. 1983. Geologia de Mkxico, Tomo mental predictability, variability, and Spermophi- III. 3a. edicibn, E. L6pez Ramos, MCxico, D.F. lus columbianuslife history over an elevational MARTIN DEL CAMPO,R. 1948. Contribucibn para el gradient. Ecology 66: 1784-1794. conocimiento de la fauna omitol6gica de1estado de Guerrero. An. Inst. Biol. Univ. Nat. Aut6n. M&xico 19:241-266. ALTITUDINAL DISTRIBUTION OF BIRDS 37
APPENDIX. Altitudinal distributions, status, abundance and habitat use of bird speciesencountered along the altitudinal transect in the Sierra de Atoyac. Sampling stations numbers are referred as in Table 1. Status is given as ? (doubtful), R (breeding), M (migrants), or W (winter resident). Abundance is given as A (abundant: seen in numbers on every visit), C (common: recorded on most visits), and R (rare: seen only one or twice in the entire study). Habitat use is indicated as F (fir forest), P (pine-oak forest), C (cloud forest), T (semideciduous tropical forest); * after the name of the taxon indicates that was not used in the analysis of altitudinal patterns becauseof its seasonal status (migrant or uncertain) or lack of detailed altitudinal range data (highly aerial species).
Station Species I 2 3 4 5 6 7 8 9 10 11 St Ab HU
Crypturellus cinnamomeus x R R T Butorides striatus x R T Cathartes aura* X x X X X R 2 TC Buteogallus anthracinus x R C T Buteo platypteru? X X M R Buteo swainsoni* X X M R : Buteo jamaicensis* X X X R? C CP Micrastur semitorquatus X X X X R R TC Falco sparverius X X R T Ortalis poliocephala X X R : T Dendrortyx macroura X X X X R A C Dactylortyx thoracicus R R PF Actitus maculartax X X W C T Columba fasciata R C P Columbina inca X X R A T Leptotila verreauxi X X R C TC Geotrygon albtfacies X X X X X R C Aratinga canicularis X X X X R 2 TC Amazona oratryx X X X X R TC Piaya cayana X X X X X X X R : TC Geococcyx velox X X R R T Crotophaga sulcirostris X X R A T OtusJIammeolus* W P Glaucidium brasilianum X X R : T Strix varia R R P Nyctydromus albicollis X X R C T Caprimulgus voctferus* X R? A P Cypseloides sp. nav.* X R R C Chaetura vauxt* X X X X X X X X X R C TCP Phaethornis superciliosus X X X X X X X X R A TC Campylopterus hemileucurus X X X X R C C Cohbri thalassinus R C P Chlorostilbon canivetii X R R T Hylocharis leucotis X X X X X R A CP Amazilia beryllina X X X X X X R TC Amazilia rutila X X R 2 Eupherusa poliocerca X X X X X X R : Lampornis amethystinus X X X X R 2 CPF Lamprolaima rhami X R R CP Eugenes fulgens X R C CP Heliomaster longirostris X X X R C TC Atthis heloisa X X X X X X X R C CP Selasphorus platycercus ’ X R? C P Selasphorus rufus* X X W CP Trogon mexicanus X X X X X X X R 2 CPF Trogon elegans X X R R C Trogon collaris X X X X X X X X R C TCP Momotus mexicanus X X R R T Chloroceryle americana X X R A T Aulacorhynchus prasinus X X X X X X X X X R A TCP Melanerpes formicivorus X X X X X X X X X R C TCPF Melanerpes chrysogenys X R R T 38 ADOLF0 G. NAVARRO S.
APPENDIX. Continued.
Species I 2 3 4 5 6 7 8 9 10 11 St Ab HU
Picoidesvillosus xR RF Veniliornisfumigatus x x x x x R R C Piculusauricularis x x x x x x x x x R C TCP Colaptesaura&s x x x x x x x R R CP Dryocopuslineatus x x x x R R TC Campephilusguatemalensis x x x x x x x R R TC Anabacerthia variegaticeps x x x x x x R c c Automolusrubiginosus x x x x x R c c Sittasomusgriseicapillus X R R C Xiuhorhvnchusflavigaster x x x R R TC Xiphorhynchuserythropygius X R c c Lepidocolaptessouleyetii X R R TC Lepidocolaptesaffinis x x x x R A CP Grallaria guatimalensis x x x x x x x x R R CPF Camptostomaimberbe X R R T Myiopagis viridicata x x x x x x R C TC Rhynchocyclusbrevirostris x x x R R C Mitrephanesphaeocercus x x x x R c CP Contopuspertinax x x x x x R A CP Empidonax minimus* x x x x x W C TC Empidonax hammondi? x x x x W c CP Emvidonax affinis x x R R PF Empidonax &icilis x x x x x x x x x R A TCP Empidonax fulvifiions X R c P Mviarchus tuberculifer x x x x x R A TC Pitangussulphuratus x x R A T Megarhynchuspitangua x x x x x R A TC Myiozetetessimilis x x R A T Myiodynastesluteiventris x x R C T Tyrannus melancholicus* X R? R T Pachyramphusaglaiae x x x R R TC Tityra semtfasciata x x x x x x R C TC Tachycinetathalassina* x x W c P Stelgidopteryxserripennis* X W Cyanocitta stelleri x x x R : :F Calocittaformosa x x R A T Cyanocoraxyncas x x x x x R c c Cyanolyca mirabilis x x x x R R CP Aphelocomaunicolor x x x R R C Parus sclateri x x x x R R CPF Certhia americana x x x R C CPF Thryothorussinaloa x x R A T Thryothorusfelix x x R A T Troglodytesaedon x x x x R C CPF Henicorhina leucophrys x x x x x x x x R c CP Cinclus mexicanus x x x x R R C Reguluscalendula ’ x x x W A CPF Sialia sialis X W c P Myadestesoccidentalis x x x x x x x x x x R A TCPF Catharus aurantiirostris x x R C T Catharus occidentalis x x x R A PF Catharus frantzii x x x x R c c Catharus”ustulatus* x x x x x W C TC Catharus guttatus ’ x W C F Turdus assimilis x x x x x x x x x R A TC Turdus rufopalliatus x x R A T Turdus migratorius x x x R A CPF Ridgwayia pinicola X R Melanotis caerulescens x x x x x R ALTITUDINAL DISTRIBUTION OF BIRDS 39
APPENDIX. Continued.
Station Species I 2 3 4 5 6 7 8 9 10 II St Ab HU Bombycilla cedrorum ’ xxxxxxxxxxwc TCPF Pitologonyscinereus x x R A CP Vireo solitarius x x x x R C TC Vireo hypochryseus x x R C T Vireo gilvus” x x W R T Vireo olivaceus x x R C T Vermivora celata* x x x x x x x W A CP Vermivora ruficapilla* x x x W A T Parula superkiosa x x R R C Dendroicapetechia* X W R T Dendroica coronatar x x W c P Dendroica occidentalis* x x x W c CP Mniotilta varia* x x x x x x x x W C TC Seiurusmotacilla* x x x x x x x x W c CP Oporornistolmiei* x x x x x x x x x x w C TCPF Wilsonia pusilla* x x x x x x x x x x W A TCP Ergaticus ruber x x x x x x x x R C CPF Peucedramustaeniatus X R Myioborus miniatus x x x x x x x x R : :P Euthlypis fachrymosa X R c c Basileuterusculicivorus x x x x R R TC Basileuterusrufifrons x x R C T Basileuterusbelli x x x x x R A CP Icteria virens+ x x W C T Habia rubica X R R T Piranga flava x x R c P Piranga rubra* X ? C T Piranga ludoviciana* x x x x x W C TC Piranga bidentata x R Chlorospingusophthalmicus x x x x x x R T: : Saltator coerulescens x x R C T Saltator atriceps x x R C T Pheucticusludovicianu? x x x x x W R C Pheucticusmelanocephalus* x x R? C P Passerinacyanea+ x x x x x x x x x W C TCP Passerinaversicolor* x x x x R? R TC Passerinaciris* X W C T Atlapetespileatus x x R c P Atlapetesbrunneinucha x x x x x x x R A C Pipilo ocai x x x R R CP Volatinia jacarina x x R C T Sporophila torqueola x x R A T Diglossabaritula x x x x R A CP Aimophila rufescens X R R T Melospiza lincolniF x x x w C PF Juncophaeonotus x x x R C PF Molothrus aeneus x x R C T Icterusgraduacauda x x x R C TC Cacicusmelanicterus x x R A T Loxia curvirostra* X R? R P Carduelis notata x x R c c