A comparison of small mammal communities in two High-Andean Polylepis woodlands in Ecuador

Reed Ojala-Barbour, Jorge Brito, William R Teska


Polylepis forest, historically widespread throughout high elevations of the central and northern Andes, now remain only in discontinuous small patches.  An expanding agricultural frontier, along with other anthropogenic pressures, imperils these remnants through further isolation and loss of habitat quality. Using two grids of live traps we compared the populations of small nonvolant mammals in an intact Polylepis woodland with one nearby that had been logged 50 years before. Our study is the first to examine the effects of habitat degradation and associated changes to vertical complexity and habitat heterogeneity on mammalian communities in Polylepis woodlands above 3500 m. The intact woodland had significantly more vertical complexity than the mid-successional woodland.  A total of 315 captures of 147 individuals of 9 species were sampled during an intensive trapping effort in 2010.  Trap success was especially high averaging 35.4 % and 28.1 % in the intact and mid-successional woodland, respectively.  Diversity and abundance of small mammals were greater in the intact woodland than the mid-successional site.  Forest specialist species were more abundant in the intact habitat; while Thomasomys paramorum, a habitat generalist, was dominant in both.  Habitat quality affected movement patterns of T. paramorum.  The results affirm a high diversity and density of small mammals in intact Polylepis woodland and indicate that the effects of habitat disturbance are species dependent.  We suggest that habitat specialists are more susceptible to loss of habitat heterogeneity and vertical complexity than habitat generalists. 

DOI: http://dx.doi.org/10.18272/aci.v11i2.516

Palabras clave

Andes, habitat degradation, habitat heterogeneity, Polylepis woodland, succession.

Texto completo:


Henderson, A., Churchill, S.P., & Luteyn, J.L. (1991). Neotropical plant diversity. Nature, 351:21–22. doi: http://dx.doi.org/10.1038/351021e0

Myers, N., Mittermeier, R.A., Mittermeier, C.G., DA Fonseca, G.A.B., & J Kent. (2000). Biodiversity hotspots for conservation priorities. Nature, 403:853–858. doi: http://dx.doi.org/10.1038/35002501

Grubb, P.J. (1977). Control of forest growth and distribution on wet tropical mountains: with special reference to mineral nutrition. Annual Review of Ecology Systematics, 8:83–107. doi: http://dx.doi.org/10.1146/annurev.es.08.110177.000503

Toivonen, J.M., Kessler, M., Ruokolainen, K., & Hertel, D. (2011). Accessibility predicts structural variation of Andean Polylepis forests. Biodiverssity and Conservation, 20:1789–1802. doi: http://dx.doi.org/10.1007/s10531-011-0061-9

Laegaard, S. (1992). Influence of fire in the grass páramo vegetation of Ecuador. In: Balslev H, Luteyn JL. (eds) Páramo. An Andean ecosystem under human influence. Academic Press, London, pp 151–170. Recovered from http://documentacion.ideam.gov.co/cgi-bin/koha/opac-detail.pl?biblionumber=26903&shelfbrowse_itemnumber=28139

Kessler, M. (2002). The “Polylepis Problem”: Where do we stand?. Ecotropica, 8:97–110. Recovered from http://www.soctropecol.eu/publications/pdf/82/Kessler%20M%202002,%20Ecotropica%208_97-110.pdf

Luteyn, J.L., & Churchill, S.P. (2000). Vegetation of the tropical Andes: an overview. In: Lentz DL (ed) An imperfect balance: landscape transformations in the Pre-Columbian Americas. Columbia University Press, New York, pp 281-310.

Moscol-Olivera., M.C., & Cleff, A.M. (2009). A phytosociological study of the páramo along two altitudinal transects in El Carchi province, northern Ecuador. Phytocoenologia, 39:79-107. doi: http://dx.doi.org/10.1127/0340-269X/2009/0039-0079

Sarmiento, F.O. (2002). Anthropogenic change in the landscapes of highland Ecuador. Geographical Review, 92:213-234. doi: http://dx.doi.org/10.1111/j.1931-0846.2002.tb00005.x

López-Sandoval, M.F. (2004). Agricultural and Settlement Frontiers in the Topical Andes: The Páramo Belt of Northern Ecuador, 1960-1990. Institut fur geographie an der Universitat Regensburg Selbstverlag. Recovered from https://bifea.revues.org/5553

Luteyn, J.L. (1992). Páramos: Why study them?. In: Balslev H, Luteyn JL (eds). Páramo. An Andean ecosystem under human influence. Academic Press, London, pp 1–14.

Chazdon, R.L., Peres, C.A., Dent, D., Sheil, D., Lugo, A.E., Lamb., D., Stork, N.E., & Miller, S.E. (2009). The potential for species conservation in tropical secondary forests. Conservation Biology, 23:1406–1417. doi: http://dx.doi.org/10.1111/j.1523-1739.2009.01338.x

Fjeldsa, J. (2002). Polylepis forests – vestiges of a vanishing ecosystem in the Andes. Ecotropica, 8:111–123. Recovered from http://www.soctropecol.eu/publications/pdf/8-2/Fjeldsa_J_2002_Ecotropica8_111-123.pdf

Cierjacks, A., Wesche, K., & Hensen, I. (2007). Potential lateral expansion of Polylepis forest fragments in central Ecuador. Forest Ecology and Management, 242:477–486. doi: http://dx.doi.org/10.1016/j.foreco.2007.01.082

Pandit, S.N., Kolasa, J., & Cottenie, K. (2009). Contrasts between habitat generalists and specialists: An empirical extension to the basic metacommunity framework. Ecology, 90:2253–2262. Recovered from http://www.jstor.org/stable/25592741

Kirkland, G.L. (1990). Patterns of initial small mammal community change after clearcutting of temperate North American forests. Oikos, 59:313–320. Recovered from http://www.jstor.org/stable/3545141

Fisher, J.T., & Wilkinson, L. (2005). The response of mammals to forest fire and timber harvest in the North American boreal forest. Mammal Review, 35:51–81. Recovered from http://www.jasontfisher.ca/uploads/6/1/0/0/61006329/fisherandwilkinson2005.pdf

Loberger, C.D, Theimer, T.C, Rosenstock, SS., & Wightman, C.S. (2011). Use of restoration-treated ponderosa pine forest by tassel-eared squirrels. Journal of Mammalogy, 92:1021–1027. doi: http://dx.doi.org/10.1644/10-MAMM-A-321.1

Barnett, A.A. (1999). Small mammals of the Cajas Plateau, southern Ecuador: ecology and natural history. Bulletin of the Florida Museum of Natural History, 42:161–217. Recovered from http://www.rebeccashapley.com/akodon/reprint_pdfs/99EcuadorLasCaJasSmallMammals.pdf

Voss, R. (2003). A New Species of Thomasomys (Rodentia: Muridae) from eastern Ecuador, with remarks on mammalian diversity and biogeography in the Cordillera Oriental. American Museum Novitates, 3421:1–47. Recovered from http://digitallibrary.amnh.org/bitstream/handle/2246/2850/N3421.pdfBodis?sequence=1

Sahley, C.T., Cervantes, K., Pacheco, V., Salas, E., Paredes, D. & Alonso, A. (2015). Diet of a sigmodontine rodent assemblage in a Peruvian montane forest. Journal of Mammalogy 96: 1071–1080. doi: https://doi.org/10.1093/jmammal/gyv112

Sahley, C.T., Cervantes, K., Salas, E., Paredes, D., Pacheco, V., & Alonso, A. (2016). Primary seed dispersal by a sigmodontine rodent assemblage in a Peruvian montane forest. Journal of Tropical Ecology, 32:125–134. doi: https://doi.org/10.1017/S0266467416000043

Moscol-Olivera, M.C., & Cleff, A.M. (2009). Vegetation composition and altitudinal distribution of Andean rain forests in El Angel and Guandera reserves, northern Ecuador. Phytocoenologia, 39:175–204. doi: http://dx.doi.org/10.1127/0340-269X/2009/0039-0175

INHAMI. unpubl. data. Meterological data for El Angel Ecological Reserve. Instituto Nacional de Metereología e Hidrología, Quito, Ecuador.

Sikes, R.S., & Gannon, W.L. (2011). Guidelines of the American Society of Mammalogists for the use of wild mammals in research. Journal of Mammalogy, 92:235–253. doi: http://dx.doi.org/10.1644/10-MAMM-F-355.1

Walpole, R.E., Meyers., R.H. Myers, S.L., & Ye, K. (1985). Probability and statistics for engineers and scientists. Macmillan Publishing, New York. Recovered from http://imse.statler.wvu.edu/files/d/9656f528-f87e-4d33-94bf-1fb7c10f0e38/ieng213.pdf

Woodman, N., Timm, R.M., SLADE, N.A., & Doonan, T.J. (1996). Comparison of traps and baits for censusing small mammals in Neotropical lowlands. Journal of Mammalogy, 77:274–281. Recovered from https://kuscholarworks.ku.edu/bitstream/handle/1808/6927/Woodman%20et%20al.1996.pdf?sequence=1&isAllowed=y

Tarifa, T., & Yensen, E. (2001). Mammals of Bolivian Polylepis woodlands. Revista Boliviana de Ecología y Conservación Ambiental, 9:29–44.

López-Arévalo, H., Montenegro-Días, O., & Cadena, A. 1993. Ecología de los pequeños mamíferos de la Reserva Biológica Carpanta, en la Cordillera Oriental Colombiana. Studies on Neotropical Fauna and Environment, 28: (4) 193–210. doi: http://dx.doi.org/10.1080/01650529309360904

Boonstra, R., & Craine, I.T.M. (1986). Natal nest location and small mammal tracking with a spool and line technique. Cannadian Journal of Zoology, 64:1034–1036. Recovered from https://tspace.library.utoronto.ca/bitstream/1807/445/2/Tracking_with_spool.pdf

Tews, J., Brose, U., Grimm, V., Tielbörger, K., Wichmann., M.C, Schwager, M, & Jeltsch, F. (2004). Animal species diversity driven by habitat heterogeneity/diversity: the importance of keystone structures. Journal of Biogeography, 31:79-92. doi: http://dx.doi.org/10.1046/j.0305-0270.2003.00994.x

Purcell, J., & Brelsford, A. (2004). Reassessing the causes of decline of Polylepis, a tropical subalpine forest. Ecotropica, 10:155-158. Recovered from http://www.soctropecol.eu/publications/pdf/10-2/Purcell,Brelsford%202004.pdf

Fox, B.J., Taylor, J.E., & Thompson, P.T. (2003). Experimental manipulation of habitat structure: a retrogression of the small mammal succession. Journal of Animal Ecology, 72:927–940. doi: http://dx.doi.org/10.1046/j.1365-2656.2003.00765.x

Ricklefs, R.E. (2008). Disintegration of the ecological community. American Naturalist, 172:74–750. Recovered from http://www.jstor.org/stable/10.1086/593002

Brito, J., Teska, W.R., & Ojala-Barbour, R. (2012). Descripción del nido de dos especies de Thomasomys (Cricetidae) en un bosque alto andino en Ecuador. Therya, 3:263–268. doi: http://dx.doi.org/10.12933/therya-12-71

Pacheco, V. (2015). Genus Thomasomys Coues, 1884. Pp: 617–682, in: Mammals of South America. Volume 2, Rodents. (JL Patton, UFJ PARDIÑAS y G D’ELÍA, eds.). The University of Chicago Press. Chicago, Estados Unidos. Recovered from http://press.uchicago.edu/ucp/books/book/chicago/M/bo18553844.html

Brito, J, Teska, W.R., & Ojala-Barbour, R. (2015). Guía de los pequeños mamíferos terrestres del bosque de Polylepis y Páramo de Frailejón del norte de Ecuador. Serie de Publicaciones del Museo Ecuatoriano de Ciencias Naturales del Instituto Nacional de Biodiversidad. INB-MECN. Publicación Patrimonio Natural del Ecuador Nro 3. Quito, Ecuador. doi: http://dx.doi.org/10.13140/RG.2.1.2400.6483

Mabry, K.E., Dreelin, E.A., & Barrett, G.W. (2003). Influence of landscape elements on population densities and habitat use of three small-mammal species. Journal of Mammalogy, 84:20–25. doi: http://dx.doi.org/10.1644/1545-1542(2003)084<0020:IOLEOP>2.0.CO;2

Mech, S.G., & Hallett, J.G. (2001). Evaluating the effectiveness of corridors: a genetic approach. Conservation Biology, 15:467-474. doi: http://dx.doi.org/10.1046/j.1523-1739.2001.015002467.x

Enlaces refback

  • No hay ningún enlace refback.

Copyright (c) 2019 Reed Ojala-Barbour, Jorge Brito M, William R Teska

Licencia de Creative Commons
Este obra está bajo una licencia de Creative Commons Reconocimiento-NoComercial 4.0 Internacional.