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TROPICAL ECOLOGY & CONSERVATION CIEE - SUMMER, 2012 - MONTEVERDE, COSTA RICA ! !TABLE OF CONTENTS ! !MICOLOGY & BOTANY Sporocarp production by bracket fungi on coarse woody debris. Elyssa Kerr. Department of Chemical Engineering, University of Washington. 1-10 Mycena citricolor on Rubiaceae in natural forest patches adjacent to coffee (Coffea Arabica: Rubiaceae). Liz Zukowski. Department! of Environmental Studies, University of Colorado at Boulder. 11 - 2 3 Stomata density and epiphytic orchid size. Amanda Abajian. Department! of Natural Resources Sciences, Washington State Univerisity 24-29 ! !PLANT-ANIMAL INTERACTIONS Avoidance of undesirable plants by the leaf-cutting ant Atta cephalotes. Jessica Bulafka. Department! of Biology, Temple University. 30-37 Nesting status and differential feeding behavior in Cloud Forest hummingbirds. Katherine Holt. Biology Department,! California Lutheran University. 38-51 Aposematic seed predation by two Neotropical mice. Pearla Romero. !Department of Biological Sciences, University of Texas. 52-60 ! !PREDATION Crypsis, warning coloration, and predator avoidance in stick insects (Phasmatodea). Valerie Feerer. Department! of Biology, Oberlin College. 61-72 Trails and nest predation in Neotropical Cloud Forest. Aforkor Amelia Quaye. !Department of Biology, Spelman College. 73-80 Carrion arthropods and habitat disturbance in Neotropical Cloud Forest. Ann Higginbotham. !Department of Biological Sciences, Purdue University. 81-88 ! !AQUATIC ECOLOGY Microhabitat, agonism, and territoriality in three color morphs of a Neotropical Cloud Forest crab. Mary Rigler. Department! of Biology, Mount Holyoke College. 89-101 Detritus, water input and pH of epiphytic bromeliad tanks. Nicholas A. George. Departments! of Engineering and International affairs, Colorado State University. 102-113 Survival and predation of two Neotropical Cloud Forest Odonates in local treatment lagoons. Lauren A. Deriaz. Institute for Biological Education, University of Wisconsin-Madison. 114 - 12 2 Odonata (Dragonflies and Damselflies) as indicators of Neotropical Cloud Forest stream contamination. Krissy Nowakowski. Departments of Geography and Environmental Studies, University of Colorado at Boulder. 123-136 Saprophytic bracket fungi on decomposing coarse woody debris: an analysis of snags and fallen material! ! !Elyssa Kerr! !Department of Chemical Engineering, University of Washington! ! ABSTRACT ! Saprophytic fungi serve an important role in the process of breaking down dead material and recycling nutrients back into the environment. To assess the growth patterns of saprophytic bracket fungi, species were observed in a premontane wet forest during the rainy season. A total of 36 morphospecies were identified on 49 pieces of fallen material and 12 snags. Shannon-Weiner diversity indices differed significantly between fallen material with an index of 2.5 and snags with an index of 2.2 despite an opposing trend in evenness. The variation in diversity was thus attributed to differential species richness. Though the variety of decomposition levels did not differ significantly between snags and fallen material, the size variety of fallen material was much greater which may account for the greater diversity if fungi specialize on various host sizes. Furthermore, trends in decomposition show that fungi occur most often on material of early-intermediate decomposition and decrease in frequency on increasingly decayed matter. This may be due to specialization of fungi in terms of feeding ecology as it relates to decreasing nutrient !availability in decaying material. !RESUMEN Los hongos saprofíticos tienen un papel importante en el proceso de descomposición de material muerto y reciclaje de nutrientes al ambiente. Para evaluar los patrones de crecimiento de orejas de palo, se observaron especies en el Bosque Premontano Húmedo durante la época lluviosa. Un total de 36 morfoespecies fueron identificadas en 49 piezas de material caído y 12 en pie. El Índice de Diversidad de Shannon-Weiner difirió significativamente entre el material caído, con un índice de 2.5, y el material en pie, con un índice de 2.2, a pesar de la tendencia opuesta en la Equidad. La variación en la diversidad fue atribuida a la diferencia en la riqueza de especies. Aunque la variedad de niveles de descomposición no fue significativamente diferente entre material caído y en pie, la variedad en tamaño del material caído fue mayor, lo cual podría contar para la mayor diversidad si los hongos se especializan en varios tamaños de hospederos. Además, los patrones en descomposición mostraron que los hongos ocurren más frecuentemente en material de temprana a mediana descomposición y disminuye su frecuencia en material cada vez más descompuesto. Esto podría deberse a la especialización de los hongos en términos de su ecología para alimentarse dado que se relaciona con la disponibilidad de nutrientes cada vez menor en el !material en descomposición. INTRODUCTION ! Fungi, a particularly poorly studied Kingdom, serve not only as an important part of ecosystems worldwide but also as a natural bank of substances with a variety of benefits to humankind (Arora 1979; Stamets 2005). Though widely unexplored, exploitation of fungal compounds has brought us antibiotics, a food source, bioremediation for oil spills, and potential treatment for a variety of diseases (Stamets 2005). Furthermore, they serve ! a valuable ecosystem service in recycling nutrients. Mycelia, a network of threadlike filaments that make up the majority of a fungal body, permeate nearly all ecosystems and drive this recycling process (Boddy 2001). In particular, saprophytic fungi, our focus, !grow and feed on dead material and aid in decomposition. Because of this reliance on dead material, saprophytic fungi are limited by the resource on which they grow. These fungi feed on the complex polymers that make up the cell walls within the dead matter (Levy 1987). Utilizing a variety of enzymatic systems, they break down these materials such as cellulose and lignin through an external digestive mechanism (Baldrian and Valskova 2008). However, decaying matter is a finite resource. These nutrients, once taken up, are not replenished within the dead material; the fungi contribute to the decomposition of the host and at the same time are diminishing their own food supply (Levy 1987). Because of the varying enzymatic toolsets used by differing fungi, different species are able to utilize different compounds within the !material (Baldrian and Valskova 2008). The macrofungi that are readily visible to the naked eye are merely the fruiting bodies or sporocarps of the organism whose lifecycle is dominated by the much more pervasive and less obvious mycelia. This sporocarp is the reproductive structure that is an indication of a certain phase within the more extensive life cycle of the fungus. Thus, the absence of sporocarps in an environment does not necessarily imply that there is no fungal population (Boddy 2001). However an analysis of sporocarp presence does give a view of the reproductive success of fungal populations (Urcelay and Robledo 2009). Saprophytic bracket fungi typically produce sporocarps that are woody and have a longer lifespan than some of the other fleshy fungi. Some bracket fungi are even perennial, maintaining a fruiting body year-round and adding new layers of material for new spore production (Arora 1979). The production of sporocarps in any fungus is dependent on nutrient !availability and the proper reproductive conditions. Bracket fungi grow and fruit on a wide range of host species (Lindblad 2000). While some saprophytes show a preference for large trees or well-decayed hosts, many others are considered to be generalists on all types of coarse woody material (Stokland and Kauserud 2004). It has been suggested that standing dead material also known as snags represents a more stressful environment and results in successful growth by a select subset of species with tolerance for such conditions (Boddy 2001; Heilmann-Clausen and Christenson 2004). Furthermore, material in contact with the ground acts as a sponge for water and nutrients in the soil making it easier to colonize and potentially a more desirable substrate overall (Levy 1987). Thus, the preference of bracket fungi to colonize, grow and reproduce on a gradient of hosts is of particular interest for conservation of potential and unexplored human benefits and the general understanding of fungal feeding ecology and reproduction. I analyzed the diversity of bracket fungi sporocarps on a variety of coarse woody debris including still standing dead trees referred to as snags and ! fallen material in the form of logs and branches in order to determine the growth habits of !this group of fungi. ! MATERIALS AND METHODS ! STUDY AREA AND SITES.—A fungal survey was carried out between 18 - 31 July 2012 in the Bajo del Tigre conservation area on the Pacific slope of the Monteverde region of Costa Rica. Elevation in this 29-hectare area ranges from 1020 to 1380 m above sea level with an annual rainfall of 2.4 m (2012, Bajo del Tigre). The area is a premontane wet forest dominated by secondary growth with some areas of primary growth. There are a number of microhabitats that result from the varied slope of the area and the temporal variation in reforestation of land that was formerly pastured. The area though has no patch with less than 20 years of growth. Because of the temporal difference in forest growth, there are also variations in canopy cover, species

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