Skip to main content

Advertisement

Log in

Differential seed and seedling predation by crabs: impacts on tropical coastal forest composition

  • Community Ecology
  • Published:
Oecologia Aims and scope Submit manuscript

Abstract

Recently, the importance of seed predation by crabs on mangrove species distributions and densities has been established by several studies. In a tropical coastal terrestrial forest in Costa Rica, we investigated the relative importance of predation by land crabs, Gecarcinus quadratus, and hermit crabs, Coenobita compressus, on measured forest composition through a series of seed removal and seedling establishment experiments. We also used natural light-gaps and adjacent non-gap sites to test how canopy cover affects crab predation (seed removal) and seedling establishment. We found fewer tree species (S=18) and lower densities (seedlings, saplings, and adults) in the coastal zone within 100 m of coastline, than in the inland zone (S=59). Land crab densities were higher in the coastal zone (3.03±1.44 crabs m−2) than in the inland zone (0.76±0.78 crabs m−2), and hermit crabs were not present in the inland zone. Seed removal and seedling mortality also were higher in the coastal zone than in the inland zone, and in the open controls than in the crab exclosures. Mortality of seeds and seedlings was two to six times higher in the controls than exclosures for four of the five experiments. Crabs preferred seeds and younger seedlings over older seedlings but showed no species preferences in the seed (Anacardium excelsum, Enterolobium cyclocarpum, and Terminalia oblonga) and seedling (Pachira quinata and E. cyclocarpum) stages. We conclude that the observed differences in tree densities were caused by differential crab predation pressure along the coastal gradient, while the differences in species composition were due to predator escape (satiation) by seed quantity. Canopy cover did not affect seed removal rates, but did affect seedling survival with higher mortality in the non-gap versus gap environments. In summary, crab predation of seeds and seedlings, and secondarily canopy cover, are important factors affecting tree establishment in terrestrial coastal forests.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1a,b
Fig. 2
Fig. 3

Similar content being viewed by others

References

  • Allen JA, Krauss KW, Hauff RD (2003) Factors limiting the intertidal distribution of the mangrove species Xylocarpus granatum. Oecologia 135:110–121

    PubMed  Google Scholar 

  • Allison PD (1995) Survival analysis using the SAS system: a practical guide. SAS Institute, Cary

    Google Scholar 

  • Ashton MS (1995) Seedling growth of co-occurring Shorea species in the simulated light environments of a rain forest. For Ecol Manage 72:1–12

    Article  Google Scholar 

  • Ball EE (1972) Observations on the biology of the hermit crab, Coenobita compressus H. Milne Edwards (Decapoda; Anomura) on the west coast of the Americas. Rev Biol Trop 20:265–273

    Google Scholar 

  • Boot RGA (1996) The significance of seedling size and growth rate of tropical rain forest tree seedlings for regeneration in canopy openings. In: Swaine MD (ed) The ecology of tropical forest tree seedlings. UNESCO, Paris, pp 267–283

    Google Scholar 

  • Clarke PJ, Myerscough PJ (1993) The intertidal distribution of the gray mangrove (Avicennia marina) in Southeastern Australia: the effects of physical conditions, interspecific competition, and predation on propagule establishment and survival. Aust J Ecol 18:307–315

    Google Scholar 

  • Coley PD, Bryant JP, Chapin FS (1985) Resource availability and plant antiherbivore defense. Science 230:895–899

    Google Scholar 

  • Dahdouh-Guebas F, Verneirt M, Tack JF, Koedam N (1997) Food preferences of Neosarmatium meinerti de Man (Decapoda: Sesarminae) and its possible effect on the regeneration of mangroves. Hydrobiologia 347:83–89

    Article  Google Scholar 

  • Denslow JS, Schultz JC, Vitousek PM, Strain BR (1990) Growth responses of tropical shrubs to treefall gap environments. Ecology 71:165–179

    Google Scholar 

  • Everham EM, Myster RW, VandeGenachte E (1996) Effects of light, moisture, temperature, and litter on the regeneration of five tree species in the tropical montane wet forest of Puerto Rico. Am J Bot 83:1063–1068

    Google Scholar 

  • Fox GA (2001) Failure-time analysis: studying times to events and rates at which events occur. In: Scheiner SM, Gurevitch J (eds) Design and analysis of ecological experiments. Oxford University Press, New York, pp 235–266

    Google Scholar 

  • Fraver S, Brokaw NVL, Smith AP (1998) Delimiting the gap phase in the growth cycle of a Panamanian forest. J Trop Ecol 14:673–681

    Article  Google Scholar 

  • Garwood NC (1996) Functional morphology of tropical tree seedlings. In: Swaine MD (ed) The ecology of tropical forest tree seedlings. UNESCO, Paris, pp 59–130

    Google Scholar 

  • Gentry, Alwyn H (1995) Diversity and floristic composition of neotropical dry forests. In: Bullock SH, Mooney HA, Medina E (eds) Seasonally dry tropical forests. Cambridge University Press, Cambridge, pp 146–194

    Google Scholar 

  • Green PT, O’Dowd DJ, Lake PS (1997) Control of seedling recruitment by land crabs in rain forest on a remote oceanic island. Ecology 78:2474–2486

    Google Scholar 

  • Hartnoll RG (1988) Evolution, systematics, and geographical distribution. In: Burggren WW, McMahon BR (eds) Biology of the land crabs. Cambridge University Press, Cambridge, pp 6–54

    Google Scholar 

  • Janzen DH (1969) Seed-eaters versus seed size, number, toxicity and dispersal. Evolution 23:1–27

    Google Scholar 

  • JMP Software (2002) JMP Help Center, vol 4, 4th edn. SAS Institute, Cary

  • Kobe RK (1999) Light gradient partitioning among tropical tree seedlings through differential seedling mortality and growth. Ecology 80:187–201

    Google Scholar 

  • Krauss KW, Allen JA (2003) Factors influencing the regeneration of the tropical Bruguiera gymnorrhiza (L.) Lamk. on a tropical Pacific Island. For Ecol Manage 176:49–60

    Article  Google Scholar 

  • Lee MAB (1985) The dispersal of Pandanus tectorius by the land crab Cardisoma carnifex. Oikos 45:169–173

    Google Scholar 

  • Lee MAB (1988) Food preferences and feeding behavior of the land crab Cardisoma carnifex. Micromesica 21:274–279

    CAS  Google Scholar 

  • Lindquist ES (2003) Patterns of coastal forest composition, structure, and recruitment, Costa Rica: functions of an environmental gradient, seed rain distribution, and crab predation pressure. PhD Dissertation. University of Georgia

  • Louda SM (1989) Differential predation pressure: a general mechanism for structuring plant communities along complex environmental gradients. Trends Ecol Evol 4:158–159

    Article  Google Scholar 

  • McGuinness KA (1997) Seed predation in a tropical mangrove forest: a test of the dominance-predation model in northern Australia. J Trop Ecol 13:293–302

    Google Scholar 

  • McKee KL (1995a) Mangrove species distribution and propagule predation in Belize: an exception to the dominance-predation hypothesis. Biotropica 27:334–345

    Google Scholar 

  • McKee KL (1995b) Seedling recruitment patterns in tropical mangrove forests: effects of establishment ability and physico-chemical factors. Oecologia 101:448–460

    Google Scholar 

  • Molofsky J, Fischer BL (1993) The effect of habitat and predation on seedling survival and growth of three shade-tolerant tree species in Panama. Ecology 74:261–265

    Google Scholar 

  • O’Dowd DJ, Lake PS (1990) Red crabs in rain forest, Christmas Island: differential herbivory of seedlings. Oikos 58:289–292

    Google Scholar 

  • O’Dowd DJ, Lake PS (1991) Red crabs in rain forest, Christmas Island: removal and fate of fruits and seeds. J Trop Ecol 7:113–122

    Google Scholar 

  • Osborne K, Smith TJ III (1990) Differential predation on mangrove propagules in open and closed canopy forest habitats. Vegetatio 89:1–6

    Google Scholar 

  • Ostertag R (1998) Belowground effects of canopy gaps in a tropical wet forest. Ecology 79:1294–1304

    Google Scholar 

  • Pearson TRH, Burslem DRFP, Mullins CE, Dalling JW (2002) Germination ecology of neotropical pioneers: interacting effects of environmental conditions and seed size. Ecology 83:2798–2807

    Google Scholar 

  • SAS (1989) SAS/STAT user’s guide, version 6, 4th edn, vol 2. SAS Institute, Cary

  • Sherman PM (2002) Effects of land crabs on seedling densities and distributions in a mainland neotropical rain forest. J Trop Ecol 18:67–89

    Google Scholar 

  • Sherman PM (2003) Effects of land crabs on leaf litter distributions and accumulations in a mainland tropical rainforest. Biotropica 35:365–374

    Google Scholar 

  • Simione G, Gignoux J, LeRoux X (2003) Tree layer spatial structure can affect savanna production and water budget: results of a 3-D model. Ecology 84:1879–1894

    Google Scholar 

  • Smith TJ III (1987a) Effects of light and intertidal position on seedling survival and growth in tropical tidal forests. J Exp Mar Biol Ecol 110:133–146

    Article  Google Scholar 

  • Smith TJ III (1987b) Seed predation in relation to tree dominance and distribution in mangrove forests. Ecology 68:266–273

    Google Scholar 

  • Smith TJ III (1988) The influence of seed predators on structure and succession in tropical tidal forests. Proc Ecol Soc Aust 15:203–211

    Google Scholar 

  • Smith TJ III (1992) Forest structure. In: Robertson AI, Alongi DM (eds) Tropical mangrove ecosystems. American Geophysical Union, Washington, pp 101–136

    Google Scholar 

  • Smith TJ III, Chan HT, McIvor CC, Robblee MB (1989) Comparisons of seed predation in tropical tidal forests from three continents. Ecology 70:146–151

    Google Scholar 

  • Sousa WP, Mitchell BJ (1999) The effect of seed predators on plant distributions: is there a general pattern in mangroves? Oikos 86:55–66

    Google Scholar 

  • Terborgh J, Wright SJ (1994) Effects of mammalian herbivores on plant recruitment in two neotropical forests. Ecology 75:1829–1833

    Google Scholar 

  • Ter-Mikaelian MR, Wagner RG, Bell FW, Shropshire C (1999) Comparison of photosynthetically active radiation and cover estimation for measuring the effects of interspecific competition on jack pine seedlings. Can J For Res 29:883–889

    Article  Google Scholar 

  • Thacker RW (1996) Food choices of land hermit crabs (Coenobita compressus H. Milne Edwards) depend on past experience. J Exp Mar Biol Ecol 199:179–191

    Article  Google Scholar 

  • Thacker RW (1998) Avoidance of recently eaten foods by land hermit crabs, Coenobita compressus. Anim Behav 55:485–496

    Article  PubMed  Google Scholar 

  • Turner IM (2001) Seeds and seedlings. In: Turner IM (ed) The ecology of trees in the tropical rain forest. Cambridge University Press, Cambridge, pp 180–226

    Google Scholar 

  • Veenendaal EM, Swaine MD, Agyeman VK, Blay D, Abebrese IK, Mullins CE (1996) Differences in plant and soil water relations in and around a forest gap in West Africa during the dry season may influence seedling establishment and survival. J Ecol 84:83–90

    Google Scholar 

  • Wolcott TG (1988) Ecology. In: Burggren WW, McMahon BR (eds) Biology of the land crabs. Cambridge University Press, Cambridge, pp 55–96

    Google Scholar 

Download references

Acknowledgements

Our work was supported by the NSF Dissertation Improvement Grant (DEB-0104791), Sigma Xi, and various field and travel award grants from the University of Georgia. We are grateful to the Costa Rica MINAE administration of San Miguel Biological Station, Cabo Blanco Absolute Nature Reserve for allowing this study to be conducted in such a restricted area, and expressing interest in the study’s findings. This study would not have been possible without the unselfish field help of numerous field assistants, with particular thanks to K. Brewster for her painstaking dedication to every seedling in our study dead or alive. We would also like to thank M. Ardón, R. Cooper, M. Hunter, K. Krauss, D. Lieberman, A. Parker, C. Peterson, P. Sherman, and two anonymous reviewers for their constructive comments on earlier versions of the manuscript. All experiments conducted in this study complied with the current laws of Costa Rica and the United States of America.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Erin Stewart Lindquist.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Lindquist, E.S., Carroll, C.R. Differential seed and seedling predation by crabs: impacts on tropical coastal forest composition. Oecologia 141, 661–671 (2004). https://doi.org/10.1007/s00442-004-1673-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00442-004-1673-5

Keywords

Navigation