Partridge (Dendrortyx Macroura) in a Temperate Coniferous Forest

J. Field Ornithol. 75(4):345–352, 2004

Abundance and distribution of the Long-tailed Wood- Partridge (Dendrortyx macroura) in a temperate coniferous forest

Gilberto Cha´vez-Leo´n1,3 and Alejandro Vela´zquez2

1 Instituto Nacional de Investigaciones Forestales, Agrıćolas y Pecuarias, Av. Latinoamericana 1101, Uruapan, Michoacań 60025, Mexico 2 Instituto de Geografıá, Universidad Nacional Autońoma de Me´xico, Morelia, Michoacań, Mexico Received 24 July 2003; accepted 5 February 2004

ABSTRACT. The Long-tailed Wood-Partridge (Dendrortyx macroura) is a species endemic to Mexico, inhabiting dense coniferous forests of the Trans-Mexican Volcanic Belt and the Sierra Madre del Sur, of which little is known about its ecology and conservation status. The abundance and density of the Long-tailed Wood-Partridge was estimated by point counts with playback distance sampling from March–October of 1998–2000 in a temperate coniferous forest managed for timber production by a Mexican indigenous community. The average detection rate was 0.31 individuals per point, resulting in a mean estimate for population density of 20.9 birds/km2 and a mean population estimate of 2679 individuals, estimated using the half-normal key function with cosine adjustments. Density estimates of the Long-tailed Wood-Partridge were 8 individuals/km2 in dry, open, scrubby habitats with deep ash and sand volcanic deposits subject to intense human use and in closed canopy, humid forests with moderate human disturbance. Density estimates were 14.6 and 21.5 individuals/km2 in humid, closed canopy, multi-stratiﬁed forests. The latter areas are recommended as the core area for protection of the Long-tailed Wood-Partridge.

SINOPSIS. Abundancia y distribucioń de Dendrortyx macroura en un bosque conifero templado La perdiz Dendrortyx macroura, es una especie ende´mica a Me´xico, de la cual se sabe muy poco de su ecologıá y estatus. Esta habita los bosques densos de conı´feros que se encuentran en la la faja volcańica trans-mexicana y la Sierra Madre del Sur. La abundancia y densidad del ave se estimo´ utilizando conteos de punto y con la ayuda de grabaciones de su vocalizacioń y estimados de distancias de respuestas. El trabajo se llevo´ a cabo de marzo–octubre de 1998–2000 en un bosque de conı´feros manejado para obtener madera por una comunidad indı´gena mexicana. La tasa de deteccioń promedio fue 0.31 individuos por punto, dando como resultado un estimado promedio de densidad de 20.9 individuos/km2 y una poblacioń promedio para toda la localidad de 2679 individuos, estimada. La densidad de aves fue de 8 individuos/km2 en habitat arbustivo, seco y abierto con depo´sitos profundos de ceniza y depo´sitos arenosos volcanicos que estań sujetos a uso intensivo por parte de humanos y en habitat con docel cerrado, hu´medo y con disturbio moderado por parte de humanos. El estimado de densidad fue de 14.6 y 21.5 individuos/km2 en habitat con docel cerrado y altamente estratificado. Se recomienda la proteccioń, en particular, de los dos u´ltimos tipos de habitats para este tipo de perdiz. Key words: density estimates, Dendrortyx macroura distance sampling, Mexico, point transects, playback

The Long-tailed Wood-Partridge (Dendrortyx abundant in the dense thickets of mountain macroura) is a Mexican endemic species pro- forests; on the contrary, Johnsgard (1973) sug- tected since 1994 (SEMARNAT 2002). It is gested that even in good habitats, its population mainly threatened by habitat loss and pertur- density was probably only about ﬁve pairs per bation (del Hoyo et al. 1994; McGowan et al. km2, and McGowan et al. (1995) estimated a 1995; Fuller et al. 2000). Parker et al. (1996) total population size between 20,000–200,000 considered this species to be of ‘‘medium’’ sen- individuals and suggested that population size sitivity to human disturbance and of a ‘‘medi- was probably decreasing. More accurate esti- um’’ conservation and research priority. There mates of population density for Long-tailed are, however, no systematic quantitative popu- Wood-Partridges are necessary to determine re- lation density estimates for this species, and search and conservation priorities. previous density estimates vary widely. For in- This wood-partridge inhabits temperate for- stance, Leopold (1959) concluded that it was ests with dense shrubs throughout the Trans- Mexican Volcanic Belt and the Sierra Madre del 3 Corresponding author. Email: calg࿞mx@yahoo. Sur (AOU 1998), an area rich in endemic plant com and animal taxa (Escalante et al. 1993; Toledo

345 J. Field Ornithol. 346 G. Cha´vez-Leoń and A. Vela´zquez Fall 2004 and Ordoń˜ez 1993) and of high economic val- bus, P. leiophylla, P. michoacana, P. douglasiana, ue (Style 1993). Industrial forestry (mainly tim- Abies religiosa, Carpinus carolineana, Quercus ber and pine-resin tapping) in this part of Mex- laurina, Q. rugosa, Q. candicans, Clethra mexi- ico has been active for several decades; however, cana, Arbutus xalapensis and Alnus jorullensis.A there has been little research into its effects on dense shrub layer, present in most of these plant native flora and fauna. communities, is dominated by Baccharis hete- Logging during the last century has per- rophylla, Cestrum nitidum, Ternstroemia pringlei, turbed most temperate forests in Mexico, and Stevia rhombifolia, Arctostaphylos discolor, and few forest tracts remain uncut. For example, of Eupatorium petiolare. The herbaceous layer is the original 93,560 km2 of pine-oak habitat in dominated by Piptochaetium virescens, Dryopte- the Sierra Madre Occidental, 571 km2 re- rus sp., Phacelia platycarpa, Asplenium praemor- mained as old-growth in 1995, a reduction of sum, Aegopogon cenchroides, and Galium mexi- 99.4% (Lammertink et al. 1996). About 80% canum. These forests are managed for timber of forest area in Mexico is controlled by indig- production using a selective cutting forestry sys- enous communities and peasants in collective tem, based on a 50-yr term with a 10-yr regen- ownership (Thoms and Betters 1998). This im- eration scheme. plies that natural resource management by these Field methods. Wood-partridge abun- rural communities will define the future con- dance and distribution were estimated using the servation of forest ecosystems in Mexico (Bocco point transect or variable circular plot method et al. 2000). Therefore, conservation efforts (Reynolds et al. 1980; Bibby et al. 2000; Buck- cannot rely only on protected reserves, but land et al. 2001) with tape playback. The use must focus also on unprotected areas, which of playback to elicit vocalizations is an effective comprise most of the remaining habitat. The method to detect elusive or secretive birds, such objective of this study was to document the dis- as the Long-tailed Wood-Partridge, and has tribution, density, and abundance of a popula- been used to estimate the abundance of various tion of the Long-tailed Wood-Partridge in a bird species (Johnson et al. 1981; Marion et al. temperate coniferous forest managed for timber 1981; Legare et al. 1999; Bibby et al. 2000; production by the indigenous community of Turcotte and Desrochers 2002). Nuevo San Juan Parangaricutiro, Michoacań, Vocalizations of the Long-tailed Wood-Par- Mexico. tridge were recorded previously in the study area with a Marantz PMD222 tape recorder STUDY AREA AND METHODS and a Sennheiser ME62 microphone equipped with a 58.4-cm Telinga parabola (following The study was conducted in lands owned by Budney and Grotke 1997). Best-quality record- the indigenous community of Nuevo San Juan ings were transferred to a three-minute endless Parangaricutiro (NSJP), located in the sub-hu- cassette and used for playback with a cassette mid temperate zone of the southwestern edge player (Sony Walkman WM-FX193) connected of the Trans-Mexican Volcanic Belt, western to a portable mini speaker (Sony SRS-A21). Michoacań, Mexico (Fig. 1). The area is be- During a two-month pilot study, most tween 19Њ21ЈNto19Њ34ЈN and 102Њ08ЈWto wood-partridges responded within 2–4 min of 102Њ17ЈW. Elevations range from 1800 m to playback and almost none after 5 min (G. Cha´- 3100 m with a mean annual precipitation of vez-Leoń, unpubl. data). Considering this, and 1200 mm concentrated from May to October the risk of behavioral disturbance when play- and mean annual temperatures not greater than back is used for extended periods of time 15ЊC. The area is about 180 km2 in size, sup- (Bibby et al. 2000), each point count was lim- porting temperate forests of pine, fir, oaks, and ited to duration of 5 min. In each point the agricultural lands. Agricultural clearings and cassette tape was played for one minute (three eruptive events of the Paricutıń volcano (1943– songs) followed by one minute of silence to de- 1952) have reduced the original forest area to tect wood-partridge vocalizations. This was re- approximately 128 km2 (Fig. 1). Fregoso (2000) peated once after which the cassette tape was described eight plant associations (Table 1) for played for 30 s followed by an additional 30 s the area. The tree layers of these forests are of silence. Since most individuals (93%) were dominated by Pinus montezumae, P. pseudostro- detected aurally, the distance to each respond- Vol. 75, No. 4 Abundance of the Long-tailed Wood-Partridge 347

Fig. 1. Study area of Comunidad Indı´gena de Nuevo San Juan Parangaricutiro (NSJP), Michoaca´n, Mexico. Gray shading in NSJP indicates forest cover; areas in white include agriculture, lava, and volcanic ash ﬁelds. ing Long-tailed Wood-Partridge was estimated. beyond 150 m, distance estimates were cate- Training to estimate distances was conducted gorized as 0–25 m, 25–50 m, 50–100 m, and during the pilot study. Because the recorder at 100–150 m. maximum volume could not be heard clearly Data were collected using the methods out-

Table 1. Plant communities identiﬁed by Fregoso (2000) in Comunidad Indı´gena de Nuevo San Juan Parangaricutiro, Michoaca´n, Mexico.

Code Plant communities Area (ha) A Pinus montezumae—Dryopterus sp. 158.9 B Baccharis heterophylla—Phacelia platycarpa 569.0 C Abies religiosa—Galium mexicanum 2046.0 D Pinus montezumae—Cestrum nitidum 1371.0 E Pinus pseudostrobus—Ternstroemia pringlei 2823.1 F Pinus leiophylla—Piptochaetium virescens 3534.6 G Carpinus carolineana—Asplenium praemorsum 374.2 H Stevia rhombifolia—Aegopogon cenchroides 246.3 Total 11,123.1 J. Field Ornithol. 348 G. Cha´vez-Leoń and A. Vela´zquez Fall 2004 lined by Buckland et al. (2001). Locations for justment functions (uniform ϩ cosine, uniform point-count sampling were established system- ϩ simple polynomial, half-normal ϩ cosine, atically in all plant associations, selecting a ran- and half-normal ϩ simple polynomial) were ex- dom starting point from a 500-m grid drawn amined during the exploratory phase of the over a vegetation map of the study area. A ran- analysis; as suggested by Buckland et al. (2001) dom direction was selected, and 10–15 individ- the model with the smallest Akaike’s Informa- ual points were set in a linear fashion separated tion Criterion (AIC) value was selected. by at least 400 m to avoid double-counting of Because of the large variability in the number individuals; the number of point counts within of Long-tailed Wood-Partridges detected and each plant association was determined propor- the small sample size in some plant associations, tionally to the area of each plant association wood-partridge density could not be estimated (Krebs 1989). Each point was sampled only in all plant associations. Therefore, we grouped once. Sampling was done during two or three plant associations following the cum ͙f rule to consecutive days each month from March to construct groups and boundaries between October of 1998–2000. No sampling was done groups, using their proportional area as on aux- from November–February because response iliary variable (Cochran 1977; Krebs 1989; Ve- rates and vocalizations decrease notably during la´zquez 1994). In this phase of the analysis only this period (G. Cha´vez-Leoń, unpubl. data). data from geo-referenced points (441) were Point transects were conducted from dawn used because they could be reliably linked to to three or four hours afterwards, in days with the vegetation units in a digital map. Wood- good weather without strong wind or rain. partridge population density was estimated for Sampling was not conducted in stands where each group of plant associations delimited by wood harvesting was taking place or took place the cum ͙f rule. We used a geographic infor- during the previous six months. This was done mation system to cluster all plant associations to avoid potential biases due to high levels of in the same group, and a map was prepared to human activity and logging machinery noise, display the distribution and density of the and the immediate effect of forest structure Long-tailed Wood-Partridge in the study area. modification on Long-tailed Wood-Partridge The significance between means among plant abundance. Most point counts (N ϭ 441; association groups was tested with the Kruskal- 57.2%) were geo-referenced with a global po- Wallis test (Zar 1984). These groups and map sitioning system (GPS) receiver (Garmin are not intended to demonstrate relationships XL12). between habitat and wood-partridge densities; Data analysis. The average number of rather they depict the spatial distribution of Long-tailed Wood-Partridge detected by point grouped plant associations and the estimated transects represents a detection probability and wood-partridge density within each plant asso- was used as an index of relative abundance. ciation. Data collected during three years (1998–2000; 711 points) were grouped in monthly bouts (N RESULTS ϭ 21) and differences between years and among the same monthly bouts were deter- During the three years of sampling, a total mined with Friedman’s test (Zar 1984). Values of 223 individuals were detected in 711 points. presented here are means Ϯ SE. A level of P Ͻ These data were grouped in monthly sampling ϭ 0.05 was accepted as significant in the analyses. bouts, from March–October (1998, N1 6; ϭ ϭ ϭ The number of individual Long-tailed 1999, N2 8; 2000, N3 7; Ntotal 21). The Wood-Partridges detected at each point-count data did not show a normal distribution (Sha- ϭ ϭ location during the three years of sampling in piro-Wilk test: W21 0.84, P 0.01); thus, the whole study area was translated into general non-parametric tests were applied in subse- estimates of density and abundance applying quent analyses. There were no significant dif- distance sampling methods (Buckland et al. ferences between the three years of sampling 1993, 2001). General density (D) and popu- (Friedman’s test: ␹2 ϭ 0.32, P ϭ 0.85), or lation size (N) in the study area were estimated among the same monthly bouts among years with program DISTANCE 4.0 (Thomas et al. (Friedman’s test: ␹2 ϭ 7.93, P ϭ 0.10). The 2002). Various combinations of the key and ad- data were thus pooled and used to determine Vol. 75, No. 4 Abundance of the Long-tailed Wood-Partridge 349

Fig. 2. Mean relative abundance of the Long-tailed Wood-Partridge during three years in Comunidad Indı´gena de Nuevo San Juan Parangaricutiro, Michoacań, Mexico. Error bars indicate Ϯ1 SE. density and abundance estimates. In the whole Three groups of vegetation associations were study area the average number of Long-tailed delimited by the cum ͙f rule using the 441 Wood-Partridges detected by point was 0.31 Ϯ geo-referenced points (128 individuals detected; 0.03 individuals, with a range of 0–4. The Table 2). Group 1 included four plant com- grouped data by monthly sampling bout indi- munities (Pinus montezumae—Dryopterus sp; cated an average detection of 10.71 Ϯ 2.29 in- Stevia rhombifolia—Aegopogon cenchroides; Car- dividuals by month, with a range of 0–41. The pinus carolineana—Asplenium praemorsum; Bac- distribution of the mean monthly detections charis heterophylla—Phacelia platycarpa) that to- showed a seasonal variation with two peaks, one gether encompassed 12% of the study area; in April and other from July–September, and group 2 included two plant communities (Pinus low detection values between them (Fig. 2). montezumae—Cestrum nitidum; Abies religio- For the general estimate of density, the half- sa—Galium mexicanum) with 32% of the total normal key function with cosine adjustments area; and group 3 included two of the largest best met the criteria (model robustness, shape plant associations (Pinus leiophylla—Piptochae- criterion, efficiency, and model fit) described by Buckland et al. (2001). This model had the tium virescens; Pinus pseudostrobus—Ternstroe- smallest AIC value (583.3) of four models with mia pringlei) with 56% of the total study area. a coefficient of variation of the estimated den- The groups were significantly different from sity of 0.26. The general estimate of density for each other in mean relative abundance of the the Long-tailed Wood-Partridge in our study Long-tailed Wood-Partridge (Kruskal-Wallis 2 ␹2 ϭ ϭ area was 20.9 Ϯ 5.4 individuals/km , with a test; 2 8.90, P 0.012). The spatial dis- 95% confidence interval of 12.6–34.6 individ- tribution of these groups was displayed in a uals. Population size was estimated to be 2679 map (Fig. 3). In group 1 the estimated density Ϯ 696.9 individuals, with a 95% confidence was 8.0 individuals/km2 (low); in group 2 the interval of 1619–4434 individuals. estimated density was 14.6 individuals/km2 J. Field Ornithol. 350 G. Cha´vez-Leoń and A. Vela´zquez Fall 2004

Table 2. Estimated density of the Long-tailed Wood-Partridge in three habitat groups (plant associations) determined by the cum͙f rule method (Krebs 1989), in Comunidad Indı´gena de Nuevo San Juan Paran- garicutiro, Michoaca´n, Mexico. Only geo-referenced points (441) were used for this analysis.

Average Estimated density Habitat group Points (N) individuals detected (individuals/km2) 1 53 0.189 8.0 2 158 0.253 14.6 3 230 0.339 21.5 Total 441

(medium); and in group 3 the estimated density tone between males and females that can help was 21.5 individuals/km2 (high). to differentiate the sex of the singing individual, although more conclusive evidence is needed. DISCUSSION Songs and calls of both sexes were heard throughout the ﬁeld study, indicating that vo- The Long-tailed Wood-Partridge is detected calizations are not given exclusively by mating more easily by its vocalizations than by direct males during the breeding season. Even though observation. Both males and females vocalize, there were minor sexual differences in the prob- as in its two congenors (D. barbatus and D. ability of response, we assumed that both sexes leucophrys). We noted small differences in voice responded equally to the playback.

Fig. 3. Distribution of the Long-tailed Wood-Partridge at Comunidad Indı´gena de Nuevo San Juan Paran- garicutiro, Michoacań, Mexico. Shadings depict Long-tailed Wood-Partridge population density levels in three plant association groups: low (group 1), medium (group 2) and high (group 3). Vol. 75, No. 4 Abundance of the Long-tailed Wood-Partridge 351 The seasonal variation in relative abundance ha). However, these are the main areas devoted of the Long-tailed Wood-Partridge (Fig. 3) may to extensive cattle grazing, and Long-tailed be more likely related to vocalization activity Wood-Partridge local population abundance than the numbers of birds present; thus, the may be low due to disturbance caused by con- low abundance detected in May and June may stant grazing. Habitats in group 1 should be reflect a diminished response to playbacks rath- subject to management to control cattle grazing er than a decrease in abundance. Nests and and to protect the remaining forest stands. chicks were found during these months in the Humid, closed canopy, multi-stratified for- study area, indicating that adults then are nest- ests characterize plant communities in habitat ing and caring for newborn chicks. Low vocal groups 2 and 3. The main human activity in activity may be a strategy to avoid predators. these communities is selective logging, pine-res- The Long-tailed Wood-Partridge calls mainly in tapping, and slight cattle grazing (Fregoso from February until April, which coincides with 2000). Groups 2 and 3 contain the largest per- the major mating season, with a peak in April centage (82%) of the total population of Long- (Warner 1959; Johnsgard 1988). The detection tailed Wood-Partridge in NSJP. These habitats probability was also high from July through should be considered the core area for protec- September, indicating an increase in vocalization and should include restrictions on cattle tion; we observed groups of up to 12 individ- grazing and less intensive logging. uals during this season. After dispersal of the Unlike direct methods (e.g., mark-recapture), young of the year, groups of two to three birds indirect techniques can be conducted at a lower are formed, and the detection probability de- cost and can provide needed information for creases until the beginning of the next mating conservation in a simple fashion (Vela´zquez season. 1994). Our results indicate that the use of dis- No other systematic population assessments tance sampling methods are effective in esti- of this species are available for comparison. The mating density of elusive and secretive quail in only prior information for this and similar spe- dense forest habitats. cies is of anecdotal nature. Johnsgard (1973) ACKNOWLEDGMENTS estimated a Long-tailed Wood-Partridge abundance of 10 individuals/km2 in ‘‘preferred’’ Funding for this study was provided by Fondo Me- xicano para la Conservacioń de la Naturaleza, A. C. cloud forest habitat. For a congenor, the Buffy- (FMCN project B-1–97/004) and Instituto Nacional de crowned Wood-Partridge (D. leucophrys), Investigaciones Forestales, Agrıćolas y Pecuarias (INIFAP Johnsgard (1973) estimated a population den- project 1475). We thank Ambrosio Rodrı´guez and Ro- sity of 33 individuals/km2 in a 6-ha study area berto Ezquivel of the Comunidad Indı´gena de Nuevo of mature pine-oak forest in Chiapas, Mexico. San Juan Parangaricutiro, who kindly gave permission to work on the study area and provided logistic support, A quantitative assessment for a forest-dwelling respectively. We appreciate the improvements in English quail, the Mountain Quail (Oreortyx pictus), es- made by Jeff Thompson through the Association of timated density in yellow pine forest, shrub- Field Ornithologists’ program of editorial assistance. steppe, and mixed forest ranged from 8.9 to 30 Two anonymous reviewers provided helpful comments on the manuscript. quail/km2 (Brennan and Block 1986). The population density estimates of the Long-tailed Wood-Partridge in our study area differ sub- LITERATURE CITED stantially from those of Johnsgard (1973) and AMERICAN ORNITHOLOGISTS’UNION. 1998. Check-list are similar to those by Brennan and Block of North American birds, 7th ed. Allen Press, (1986) for O. pictus in mixed forests. Lawrence, KS. Environmental conditions in habitat group 1 BIBBY, C. J., N. D. BURGESS,D.A.HILL, AND S. H. are heterogeneous, including dry, open, scrubby MUSTOE. 2000. Bird census techniques, 2nd ed. Academic Press, London, UK. habitats in deep ash and sand deposits from BOCCO, G., A. VELA´ZQUEZ, AND A. TORRES. 2000. Paricutıń volcano, which are also subject to Ciencia, comunidades indı´genas y manejo de re- heavy human activity. Group 1 also includes cursos naturales: un caso de investigacioń partici- humid, closed canopy, multistratified forests pativa en Me´xico. Interciencia 25: 64–71. BRENNAN, L. A., AND W. M. BLOCK. 1986. Line transect with moderate human disturbance. All plant estimates of Mountain Quail density. Journal of communities in this category occupy smaller ar- Wildlife Management 50: 373–377. eas than the other plant communities (Ͻ600 BUCKLAND, S. T., D. R. ANDERSON,K.P.BURNHAM, J. Field Ornithol. 352 G. Cha´vez-Leoń and A. Vela´zquez Fall 2004

AND J. L. LAAKE. 1993. Distance sampling: esti- MARION, W. R., T. E. O’MEARA, AND D. S. MAHER. mating abundance of biological populations. Chap- 1981. Use of playback recordings in sampling elu- man and Hall, London, UK. sive or secretive birds. Studies in Avian Biology 6: ———, ———, ———, ———, D. L. BORCHERS, 81–85. AND L. THOMAS. 2001. Introduction to distance MCGOWAN, P. J. K., S. D. DOWELL,J.P.CARROLL, AND sampling: estimating abundance of biological pop- N. J. AEBISCHER. 1995. Partridges, quails, franco- ulations. Oxford University Press, Oxford, UK. lins, snowcocks and guineafowl; status survey and BUDNEY,G.F.,AND R. W. GROTKE. 1997. Techniques conservation action plan 1995–1999. IUCN/SSC, for audio recording vocalizations of tropical birds. Cambridge, UK. Ornithological Monographs 48: 147–163. PARKER, T. A., III, D. F. STOTZ, AND J. W. FITZPATRICK. COCHRAN, W. G. 1977. Sampling Techniques, 3rd ed. 1996. Ecological and distributional databases. In: John Wiley, New York. Neotropical birds: ecology and conservation (D. F. DEL HOYO, J., A. ELLIOT, AND J. SARGATAL Eds. 1994. Stotz, J. W. Fitzpatrick, T. A. Parker, III, and D. Handbook of the birds of the world, vol. 2. New K. Moskovits, eds.), pp. 113– 401. University of World vultures to guineafowl. Lynx Edicions, Bar- Chicago Press, Chicago, IL. celona, Spain. REYNOLDS, R. T., J. M. SCOTT, AND R. A. NUSSBAUM. ESCALANTE PLIEGO, P., A. G. NAVARRO SIGU¨ ENZA, AND 1980. A variable circular-plot method for estimat- A. T. PETERSON. 1993. A geographic, ecological, ing bird numbers. Condor 82: 309–313. and historical analysis of land bird diversity in Mex- SEMARNAT (SECRETAR´ıADELMEDIO AMBIENTE Y RE- ico. In: Biological diversity of Mexico: origins and CURSOS NATURALES). 2002. Norma Oficial Mexi- distribution (T.P. Ramamoorthy, R. Bye, A. Lot and cana NOM-059-ECOL-2001, Proteccioń ambien- J. Fa, eds.), pp. 281–307. Oxford University Press, tal, Especies nativas de Me´xico de flora y fauna sil- New York. vestres, Categorıás de riesgo y especificaciones para FREGOSO, D. A. 2000. La vegetacioń herramienta base su inclusioń, exclusioń o cambio, Lista de especies para la planeacioń, aprovechamiento y conservacioń en riesgo. In: Diario Oficial de la Federacioń, se- de los recursos forestales: el caso de la comunidad gunda seccioń, 6 March 2002, pp. 95–190. indı´gena de Nuevo San Juan Parangaricutiro, Mich. STYLE, B. T. 1993. Genus Pinus: a Mexican purview. In: Me´xico. B. S. thesis. Facultad de Ciencias, UNAM, Biological diversity of Mexico: origins and distri- Mexico. bution (T. P. Ramamoorthy, R. Bye, A. Lot, and J. FULLER, R. A., J. P. CARROLL, AND P. J. K. MCGOWAN. Fa, eds.), pp. 397–420. Oxford University Press, 2000. Status survey and conservation action plan New York. 2000–2004: partridges, quails, francolins, snow THOMAS, L., J. L. LAAKE,S.STRINDBERG,F.F.C. cocks, guineafowl and turkeys. IUCN, Gland, Swit- MARQUES,S.T.BUCKLAND,D.L.BORCHERS,D. zerland. R. ANDERSON,K.P.BURNHAM,S.L.HEDLEY, AND JOHNSGARD, P. A. 1973. Grouse and quails of North J. H. POLLARD. 2002. Distance 4.0, Release 1. [On- America. University of Nebraska Press, Lincoln, line]. Research Unit for Wildlife Population Assess- NE. ment, University of St. Andrews, United Kingdom. ———. 1988. The quails, partridges, and francolins of http://www.ruwpa.stand.ac.uk/distance/ the World. Oxford University Press, New York. THOMS,C.A.,AND D. R. BETTERS. 1998. The potential JOHNSON, R. R., B. T. BROWN,L.T.HIGHT, AND J. M. for ecosystem management in Mexico’s forest eji- SIMPSON. 1981. Playback recordings as a special avi- dos. Forest Ecology and Management 103: 149– an censusing technique. Studies in Avian Biology 157. 6: 68–75. TOLEDO, V. M., AND M. J. ORDO´ N˜ EZ. 1993. The bio- KREBS, C. J. 1989. Ecological methodology. Harper and diversity scenario of Mexico: a review of terrestrial Row, New York. habitats. In: Biological diversity of Mexico: origins LAMMERTINK, J. M., J. A. ROJAS TOME´,F.M.CASILLAS and distribution (T. P. Ramamoorthy, R. Bye, A. ORONA, AND R. L. OTTO. 1996. Status and con- Lot, and J. Fa, eds.), pp. 757–777. Oxford Uni- servation of old-growth forests and endemic birds versity Press, New York. in the pine-oak zone of the Sierra Madre Occiden- TURCOTTE,Y.,AND A. DESROCHERS. 2002. Playbacks of tal, Mexico. Verslagen en Technische Gegevens. No. mobbing calls of Black-capped Chickadees help es- 69. Institute for Systematics and Population Biol- timate the abundance of forest birds in winter. Jour- ogy (Zoological Museum), University of Amster- nal of Field Ornithology 73: 303–307. dam, The Netherlands. VELA´ZQUEZ, A. 1994. Distribution and population size LEGARE, M. L., W. R. EDDLEMAN,P.A.BUCKLEY, AND of Romerolagus diazi on El Pelado volcano, Mexico. C. KELLY. 1999. The effectiveness of tape playback Journal of Mammalogy 75: 743–749. in estimating Black Rail density. Journal of Wildlife WARNER, D. W. 1959. The song, nest, eggs, and young Management 63: 116–125. of the Long-tailed Partridge. Wilson Bulletin 71: LEOPOLD, A. S. 1959. Wildlife of Mexico: the game 307–312. birds and mammals. University of California Press, ZAR, J. H. 1984. Biostatistical analysis, 2nd ed. Prentice- Berkeley, CA. Hall, Englewood Cliffs, NJ.