International Journal of Primatology

, Volume 32, Issue 3, pp 634–651

Absence of Howlers (Alouatta palliata) Influences Tree Seedling Densities in Tropical Rain Forest Fragments in Southern Mexico

  • Alberto Anzures-Dadda
  • Ellen Andresen
  • María Luisa Martínez
  • Robert H. Manson
Article

DOI: 10.1007/s10764-011-9492-0

Cite this article as:
Anzures-Dadda, A., Andresen, E., Martínez, M.L. et al. Int J Primatol (2011) 32: 634. doi:10.1007/s10764-011-9492-0

Abstract

The disappearance of frugivorous primates in fragmented forests can potentially lower the rates of seed dispersal and recruitment of endozoochorous tree species, thus altering plant community structure. We quantified seedling density for 7 tree species that are common in the feces of mantled howlers (Alouatta palliata) in 6 rain forest fragments in northern Chiapas, Mexico. Howlers were present in 3 of the fragments and absent in the other 3. We compared seedling density in primate sleeping sites in inhabited fragments with control sites, which were structurally similar to sleeping sites but where we did not find monkey feces, in both inhabited and uninhabited fragments. For each tree species, we determined the relationship between seedling density and the local density of seeds and adult trees. In fragments where howlers were present, seedling density for 4 of the focal tree species (Brosimum alicastrum, Dialium guianense, Manilkara zapota, and Nectandra ambigens) was greater in sleeping sites than in control sites found in the same fragments. Moreover, seedling density of Dialium guianense was greater in the control sites of fragments inhabited by howlers than in fragments where this primate is absent. Seedling density of these 4 species correlates positively with seed density on the forest floor; however, we observed no correlations between seedling density and the density of adult trees. Our results suggest that the diversity of the seedling community of tree species dispersed by howlers may decline in fragments where this seed disperser is absent. These findings, together with the fact that only 5% of the study region is currently covered by forest and 81% of the forest remnants are uninhabited by mantled howlers, suggest that the potential long-term recovery of associated populations of tropical tree species dispersed by this primate species is highly uncertain. Conservation and restoration efforts should be aimed at restoring or replacing the ecological role played by this important seed disperser in the region.

Keywords

Cascade effectsConservationForest fragmentationHowlersSeed dispersalSeedling recruitment

Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Alberto Anzures-Dadda
    • 1
    • 2
  • Ellen Andresen
    • 3
  • María Luisa Martínez
    • 4
  • Robert H. Manson
    • 4
  1. 1.Red de Manejo Biorracional de Plagas y VectoresInstituto de Ecología, A.C.XalapaMexico
  2. 2.Area de Conservación de la BiodiversidadEl Colegio de la Frontera SurSan Cristóbal de Las CasasMéxico
  3. 3.Centro de Investigaciones en EcosistemasUniversidad Nacional Autónoma de MéxicoMoreliaMexico
  4. 4.Red de Ecología FuncionalInstituto de Ecología, A.C.XalapaMexico