Zak (Rakan) Zahawi

Cooperating Graduate Faculty in Botany; Director of Lyon Arboretum

PhD 2003 University of Illinois at Urbana-Champaign

Contact Information
Phone: (808) 988-0457

Link to ResearchGate

Graduate Faculty Memberships
Botany, Natural Resources and Environmental Management (NREM)

Research Interests

Design and evaluation of cost-effective restoration strategies that facilitate or accelerate forest recovery in degraded habitats, particularly the Neotropics

Forest dynamics and plant succession in fragmented tropical landscapes

Vegetative propagation of tropical trees and their application in restoration

Research Statement

My research has evaluated theoretical ecological concepts centered on forest recovery in degraded tropical habitats with the goal of developing cost-effective strategies to facilitate or accelerate this process. I have conducted both observational and experimental research in Central and South America and established large- and small-scale projects with collaborators and students from multiple institutions. This includes projects that have evaluated applied nucleation as a restoration strategy, the use of large vegetative cuttings (≥2 m tall) in restoration, and the potential for utilizing agricultural waste to aid in recovery. I have also examined forest dynamics in habitat fragments and quantified land use change patterns over long-time scales. I am dedicated to furthering scientific advancement in my fields of research, but I am also committed to applying this research knowledge to advancing conservation goals wherever this research is being conducted.

Selected Publications

Zahawi, R.A, F. Oviedo-Brenes, and C.J. Peterson. 2017. A degradation debt? Large-scale shifts in community composition and loss of biomass in a tropical forest fragment after 40 years of isolation. PLoS One 12(8): e0183133.

Reid, J.L., S.J. Wilson, G.S. Bloomfield, M.E. Cattau, M.E Fagan, K.D. Holl, and R.A. Zahawi. 2017. How long do restored ecosystems persist? Annals of the Missouri Botanical Garden 102:258-265.

Holl, K.D., J. M. Chaves-Fallas, F. Oviedo-Brenes, J.L. Reid, and R.A. Zahawi. 2017. Tropical forest restoration strategies affect biodiversity recovery more strongly than does landscape forest cover. Journal of Applied Ecology. DOI: 10.1111/1365-2664.12814.

Holste, E.K., K.D. Holl, R.A. Zahawi, and R.K. Kobe. 2016. Reduced aboveground tree growth associated with higher arbuscular mycorrhizal fungal diversity in tropical restoration. Ecology and Evolution. DOI: 10.1002/ece3.2487.

Cole, R., K.D. Holl, R.A. Zahawi, P. Wickey, and A. Townsend. 2016. Leaf litter arthropod responses to tropical forest restoration. Ecology and Evolution 6: 5158–5168. DOI: 10.1002/ece3.2220.

Reid, J.L., J. Miguel Chaves-Fallas, K.D. Holl, and R.A. Zahawi. 2016. Tropical forest restoration enriches vascular epiphyte recovery. Applied Vegetation Science 19:508-517.

Holl, K.D. and R.A. Zahawi. 2015. “Ilhas de árvores” como uma estratégia prática para a restauração de florestas tropicais. In Brancalion, P.H.S., Gandolfi, and R.R. Rodrigues. Restauração florestal. Oficina de Textos, São Paulo.

Zahawi, R.A., G. Duran, and U. Kormann. 2015. Sixty-seven years of land use change in southern Costa Rica. PLoS One DOI: 10.1371/journal.pone.0143554.

Zahawi, R.A., J.L. Reid, and K.D. Holl. 2015. Passive restoration can be an effective strategy: a reply to Prach and del Moral. Restoration Ecology 23:347-348.

Reid, J.L., C.D. Mendenhall, R.A. Zahawi, and K.D. Holl. 2015. Scale-dependent effects of forest restoration on Neotropical fruit bats. Restoration Ecology DOI: 10.1111/rec.12235.

Slik, F. and 170 others. 2015. An estimate of the number of tropical tree species. Proceedings of the National Academy of Sciences.

Reid, J.L., K.D. Holl, and R.A. Zahawi. 2015. Seed dispersal limitations shift over time in tropical forest restoration. Ecological Applications 25:1072-1082.

Paine, C.E.T., and 34 others. 2015. Globally, functional traits are weak predictors of juvenile tree growth, and we do not know why. Journal of Ecology doi: 10.1111/1365-2745.12401.

Zahawi, R.A., J.P. Dandois, K.D. Holl, D. Nadwodny, J.L. Reid, and E.C. Ellis. 2015. Using lightweight unmanned aerial vehicles to monitor tropical forest recovery. Biological Conservation 186:287-295.

Zahawi, R.A., C. Eckert, J.M. Chaves-Fallas, L. Schwanitz, J.A. Rosales, and K.D. Holl. 2015. The effect of restoration treatment soils and parent tree on tropical forest tree seedling growth. Open Journal of Forestry 5(2); DOI: 10.4236/ojf.2015.52015.

Zahawi, R.A., J.L. Reid, and K.D. Holl. 2014. Hidden costs of passive restoration. Restoration Ecology 22:284-287.

Zahawi, R.A. and K.D. Holl. 2014. Evaluation of different tree propagation methods in ecological restoration in the Neotropics. Pages 85-96. In Bozzano, M., R. Jalonen, E. Thomas, D. Boshier, L. Gallo, S. Cavers, S. Bordács, P. Smith, & J. Loo (eds). Genetic considerations in ecosystem restoration using native tree species. State of the World’s Forest Genetic Resources – Thematic Study. Rome, FAO and Biodiversity International.

Reid, J.L., C. D. Mendenhall, J.A. Rosales, R.A. Zahawi, and K.D. Holl. 2014. Landscape context mediates avian habitat choice in tropical forest restoration. PLoS One 9:e90573.

Reid, J.L., E.K. Holste, K.D. Holl, and R.A. Zahawi. 2014. Does any bat box facilitate forest recovery? – Reply to Kelm. Biological Conservation 170:330-331.

Holl, K.D. and R.A. Zahawi. 2014. Factors explaining variability in woody above-ground biomass accumulation in restored tropical forest. Forest Ecology and Management 319:36-43.

Holl, K.D., V. M. Stout, J.L. Reid, and R.A. Zahawi. 2013. Does applied nucleation enhance habitat heterogeneity and tree diversity in restored tropical pasture? Oecologia 173:569-578.

Reid, J.L., E.K. Holste, and R.A. Zahawi. 2013. Artificial bat roosts did not accelerate forest recovery in abandoned pastures in southern Costa Rica. Biological Conservation 167:9-16.

Zahawi, R.A., K.D. Holl, R.J. Cole, and J.L. Reid. 2013. Testing applied nucleation as a restoration strategy to facilitate tropical forest recovery. Journal of Applied Ecology 50: 88-96.

Cayuela, L., L. Gálvez-Bravo, F.S. de Albuquerque, R. Pérez-Pérez, D.J. Golicher, R.A. Zahawi, and 47 others. 2012. La red internacional de inventarios forestales (BIOTREE-NET) en Mesoamérica: avances, retos y perspectivas futuras. Ecosistemas 21: 126-135.

Cayuela, L., L. Gálvez-Bravo, R. Pérez-Pérez, F.S. de Albuquerque, D.J. Golicher, R.A. Zahawi, and 45

others. 2012. The tree biodiversity network (BIOTREE-NET): Prospects for biodiversity research and conservation in the tropics. In J. Dengler, J. Oldeland, F. Jansen, M. Chytry, J. Ewald, M. Finckh, F. Glöckler, G. Lopez-Gonzalez, R. K. Peet, J. H. J. Schaminée (eds). Vegetation databases for the 21st century. Biodiversity & Ecology 4: 211–224.

Reid, J.L., J.B.C. Harris, and R.A. Zahawi. 2012. Avian habitat preference in tropical forest restoration in southern Costa Rica. Biotropica 44:350-359.

Lindell, C.A., R.J. Cole, K.D. Holl, and R.A. Zahawi. 2012. Migratory bird species in young tropical forest restoration sites: effects of vegetation height, planting design, and season. Bird Conservation International 22:94-105.

Celentano, D., R.A. Zahawi, B. Finegan, F. Casanoves, R. Ostertag, R.J. Cole, and K.D. Holl. 2011.

Restauración ecológica de bosques tropicales en Costa Rica: efecto de diferentes modelos en la producción, acumulación y descomposición de hojarasca. Revista de Biología Tropical 59:1323-1336.

Holl, K.D., R.A. Zahawi, R.J. Cole, R. Ostertag, and S. Cordell. 2011. Planting seedlings in plantations versus tree islands as a large-scale tropical forest restoration strategy. Restoration Ecology 19: 470-479.

Celentano, D., R.A. Zahawi, B. Finegan, R. Ostertag, R.J. Cole, and K.D. Holl. 2011. Litterfall dynamics and nutrient cycling under different strategies for tropical forest restoration. Biotropica 43:279-287.

Cole, R., K.D. Holl, C.L. Keene, and R.A. Zahawi. 2011. Direct seeding of late successional trees to restore tropical montane forest. Forest Ecology and Management 261:1590-1597.

Zahawi, R.A. and K.D. Holl. 2010. Bridging the gap between scientific research and tropical forest restoration: a multi-faceted research, conservation, education, and outreach program in southern Costa Rica. Ecological Restoration 28:143-146.

Sady, G.C., K.D. Holl, R.A. Zahawi, and R.J. Cole. 2010. Germination and survival of four early successional tree species in tropical montane forest restoration. Ecological Restoration 28:121-124.

Cole, R.J., K.D. Holl, and R.A. Zahawi. 2010. Seed rain under different restoration strategies in a complex tropical agricultural landscape. Ecological Applications 20:1255-1269.

Morrison, E., C.A. Lindell, K.D. Holl, and R.A. Zahawi. 2010. Patch-size effects on avian foraging behaviour: implications for tropical forest restoration design. Journal of Applied Ecology 47:130-138.

Zahawi, R.A. and K.D. Holl. 2009. Comparing the performance of tree stakes and seedlings to restore abandoned tropical pastures. Restoration Ecology 17:854-864.

Fink, R.D., C.A. Lindell, E.B. Morrison, R.A. Zahawi and K.D. Holl. 2009. Patch size and tree species influence the number and duration of bird visits in restoration plots in southern Costa Rica. Restoration Ecology 17:479-486.

Zahawi, R.A. and K.D. Holl. 2008. Tropical forest restoration research opportunities in southern Costa Rica. Ecological Restoration 26:299-300.

Reid, J.L., J.B.C. Harris, L.J. Martin, J.R. Barnett, and R.A. Zahawi. 2008. Distribution and abundance of nearctic-neotropical songbird migrants in a forest restoration site in southern Costa Rica. Journal of Tropical Ecology 24:685-688.

Zahawi, R.A. 2008. Instant trees: using giant vegetative stakes in tropical forest restoration. Forest Ecology and Management 255:3013-3016.

Schlawin, J.R. and R.A. Zahawi. 2008. ‘Nucleating’ succession in recovering neotropical wet forests: the legacy of remnant trees. Journal of Vegetation Science 19:485-492.

Goldsmith, G.R. and R.A. Zahawi. 2007. The function of stilt roots in the growth strategy of Socratea exorrhiza (Arecaceae) at two neotropical sites. Revista de Biología Tropical 55:787-793.

García-C.J.M. and R.A. Zahawi. 2006. Predation by a Blue-crowned motmot on a hummingbird. The Wilson Bulletin 118:261-263.

Zahawi, R.A. and C.K. Augspurger. 2006. Tropical forest restoration: tree islands as recruitment foci in degraded lands of Honduras. Ecological Applications 16:464-478.

Zahawi, R.A. 2005. Establishment and growth of living fence species: an overlooked tool for the restoration of degraded areas in the tropics. Restoration Ecology 13:92-102.

Zahawi, R.A. and C.K. Augspurger. 1999. Early plant succession in abandoned pastures in Ecuador. Biotropica 31:540-552.