Chris Free April 16 th 2010 Research Symposium

 Valuable timber species  Workable, durable, beautiful  Decorative woodwork, furniture, etc  Single tree - $20,000, $1800 m -3

 Vulnerable to exploitation  Natural range – rapid anthropogenic land conversion  Life history - low density, secondary colonizer, disturbance dependent seedling regeneration

 Deforestation over 63% of mahoganies range  Selective logging of 85-90% remaining adults Grogan et al. 2009

 CITES Appendix II - demonstration of sustainable harvest by exporting country  Little empirical basis for evaluating sustainability of proposed regulations Inclusion in Appendix II of the neotropical populations of Swietenia macrophylla King, (Meliaceae), including logs, sawn timber, veneer and plywood, in accordance with Article II, Paragraph 2A, of the Convention and Resolution Conference 9.24, Annex 2A. The objective of this listing is to promote sustainable management of S. macrophylla in order to help ensure its further conservation and trade (CITES 2002).

 Verwer et al. (2009), Grogan et al. (2009), Grogan and Landis (in prep) – spatially implicit matrix based and individual based modeling strategies  No density-dependence - requires spatially explicit approach Grogan and Landis (in prep)

 Population size/density modifies population vital rates (recruitment, growth, mortality)  Competition, predation, pathogens, disease  Janzen-Connell Model: distant and/or density responsive enemies cause increased mortality of progeny near parent forcing spacing of conspecifics

 Distant- and density-dependent interactions observed in big-leaf mahogany populations  Leaf herbivory by specialist moth caterpillar ▪ Increased defoliation and seed predation ▪ Decreased growth and recruitment success Norghauer et al. 2006a

 The purpose of my project is to examine the population-level consequences of density- dependence on big-leaf mahogany  Develop a more robust population growth model  Assess applicability of Janzen-Connell predictions

 A spatially explicit model developed using NetLogo language and interface  Parameterized using the field data of Grogan and Landis (in prep) and Norghauer (2006a,b)  204 ha 100% inventoried field site in Pará, Brazil  Experimental exclosures in Pará, Brazil  Disturbance, growth, mortality, reproduction

 Convention on International Trade in Endangered Species (CITES) Consideration Of Proposals For Amendment Of Appendix I And II: Swietenia macrophylla. Prop [ accessed 14 March 2010].  Grogan, J., and Landis, R.M Mahogany population dynamics in Brazil and implications for international trade. Forthcoming.  Grogan, J., Blundell, A.G., Landis, R.M., Youatt, A., Gullison, R.E., Martinez, M., Kometter, R., Lentini, M., and Rice, R.E Over-harvesting driven by consumer demand leads to population decline: big-leaf mahogany in South America. Conservation Letters 3:  Norghauer, J.M., Malcolm, J.R., and Zimmerman, B.L Juvenile mortality and attacks by a specialist herbivore increase with conspecific adult basal area of Amazonian Swietenia macrophylla (Meliaceae). Journal of Tropical Ecology 22:  Verwer, C., Peña-Claros, M., van der Staak, D., Ohlson-Kiehn, K., and Sterck, F.J Silviculture enhances the recovery of overexploited mahogany Swietenia macrophylla. Journal of Applied Ecology 45: