Mentors for next summer

Projects and Mentors

Summer 2018 

Aquatic insect ecology

Dr. Alonso Ramírez works on the ecology of aquatic insects in the streams and rivers within the Luquillo Experimental Forest, with emphasis on the role that aquatic insects play on ecosystem processes. Students will be involved in projects that focus on (1) assessing physicochemical factors affecting insect assemblages, (2) interaction between insects and shrimps and fishes, and (3) the role of insects in ecosystem processes, such as detritus decomposition and control of primary production. Students could develop projects in any of these areas and complement ongoing research or uncover new lines of research for future study.

Caddisfly (Trichoptera) and Mosquito (Diptera) Ecology

Limarie Reyes is a Ph.D. student in the Biological Sciences Department at the University of Southern Mississippi. Depending on the REU student’s interest, the project may focus in caddisflies (1) or mosquitoes (2). Both project ideas will emphasize natural disturbances (hurricanes) on the populations.

(1) The caddisfly project will evaluate the effects of hurricanes on Phylloicus pulchrus (Trichoptera) populations in a tropical stream. The data collected can be compared with available pre-hurricane data of the population to get initial insights on how disturbances in the habitat might shift population dynamics.

(2) The mosquito project will assess vector mosquito (dengue, Zika, chikungunya) larval and adult abundance from urban areas (San Juan Metropolitan area) and rural areas (Luquillo Experimental Forest) in Puerto Rico after the impact of two consecutive hurricanes

Rodent Ecology and Plant-Animal Interactions

Dr. Aaron Shiels (USDA, National Wildlife Research Center) works on rodent ecology and plant-animal interactions in tropical environments. Most of his research findings are applied towards improving ecosystem management and native species conservation. Students will develop independent projects focused on (1) plant herbivory/predation by ground-dwelling mammals, birds, and invertebrates, and (2) assessments of invasive mammal (i.e., rats, mongoose) activity in disturbed and undisturbed forest habitats.

Plant Population Ecology and Invasive Species Biology

Dr. James D. Ackerman, UPR-RP, conducts research in 3 main areas in which REU students can develop their independent projects: (1) Natural selection and the evolution and maintenance of deception pollination systems in the orchid family; (2) Dispersion of orchids and its relationship to land use history and recruitment; and (3) Invasive plant species biology. The first has its roots in evolutionary biology using Darwin's favorite model system, the orchids. As orchids are one of the most diverse groups of plants with a remarkable array of adaptations for survival and for specialized pollination, orchids are a good model system to gain insight in the diversification of flowering plants. The goal is to detect natural selection when reproductive success is rare and how these conditions affect the loss or gain of phenotypic variation. With analytical tools such as cubic spline analysis and Bayesian statistics, the importance of genetic drift and selection in plant evolution can be detected. The second area involves the spatial aspects of reproductive success from seed germination to growth, development, flowering, fruiting, seed production and dispersal. This work links directly with studies of natural selection and evolution, but emphasizes ecological aspects at local and landscape scales combining field experiments with spatial statistics and GIS technology. For the third area, invasive species, tropical islands are prone to invasions and Puerto Rico is just beginning to see an explosion in the number of exotic species becoming naturalized and invasive. How such species affect ecosystem function and what might be the pattern of spread is of great interest to the integrity natural areas. Demographic studies utilizing transition matrices, reproductive ecology, and utilization of species distribution models are the tools to be used to address these problems.

Wetland and Riparian Ecology

Dr. Tamara Heartsill-Scalley, USFS , studies ecological interconnections (e.g., energy and biomass flow) between terrestrial and aquatic ecosystems.  REU students can develop their independent projects in topics related to: (1) energy flows from riparian zones into headwater streams, (2) patterns of understory vegetation in riparian zones under different environmental conditions, and (3) export of biomass and nutrients from headwater streams to downstream ecosystems (4) forested wetland restoration, population and ecosystems dynamics.

The Luquillo Mountains and associated wetland systems provide an ideal setting for the study of interconnections among ecosystems and their vegetation communities.  In addition to the longitudinal elevation and rainfall gradient in the mountains there are also lateral gradients related to topographical settings that link terrestrial and aquatic systems. REU student projects could use a combination of techniques to assess population structure dynamics, community composition, biomass pools in neighboring ecosystems and flows among these. Techniques include vegetation identification, biomass quantification using traps, element ratio analysis and multivariate statistics.

Insect Ecology

Nicole Scavo is a Master's student at the University of Southern Mississippi. Students will develop projects in one of three research areas dealing with insect ecology in the San Juan metropolitan area or the Luquillo Experimental Forest. The topic areas include: (1) assessing mosquito communities in urban areas and their relationship to socio-economic variables, (2) assessing the effects of a large disturbance event (hurricane) on the mosquito community of the Luquillo Experimental Forest, and (3) comparing the diversity of litter invertebrate communities along an elevational gradient.

Meiofauna and Protists Ecology

Josué Santiago-Vera is a Ph.D. student in the Environmental Sciences Department at the University of Puerto Rico in Río Piedras. Currently, he is interested on disturbance effects (hurricane) on community structure of meiofauna in streams. Using manipulation experiments (artificial stream channels), students will develop an independent project to evaluate effects of hurricanes (canopy gap, litter dams, sedimentation, floods) on a community level using meiofaunal species or protists as model organisms.

Nutrient cycling and rhizosphere ecology

Daniela Yaffar is a Ph.D. student in the Ecology and Evolutionary Biology Department at the University of Tennessee. Her dissertation is focused on tropical plant roots/soils nutrient interaction and their plasticity in the response to disturbance. REU students can develop independent projects on one of the following areas: (1) Fine-root trait plasticity in response to Hurricanes, (2) Fine-root architecture, morphology, and chemistry in response to experimental drought (for this we will need to build small water exclusion shelters), and (3) leaf and root traits of two champion species, one native (Prestoea montana), and one introduced (Spathodea campanulata), both widely dispersed and dominant in Puerto Rico.  Fine roots are essential for plant structure and function, but also for ecosystem nutrient cycling and biotic interactions in the rhizosphere. Measuring and comparing different root traits in a tropical forest is still a poorly explored field in science. REU students can make an important contribution for nutrient cycling models; it just takes a little “digging”.