Population structure of Amazonian fruit camu camu (Myrciaria dubia) in Peru after decades of harvest
Problem Statement, Research Questions, and Research Objectives
The sustainable management of non-timber forest products can be an economically viable alternative to land conversion in tropical forests and can conserve biodiversity and ecosystem services while also generating income for local communities (Peters et al. 1989a). The tropical fruit camu camu [Myrciaria dubia (HBK) McVaugh] is harvested from wild stands in the Amazonian floodplains of Peru, and has a high potential for sustainable management (McVaugh 1963, Penn 2004). However, commercial interest in camu camu has increased harvest intensity on wild stands, potentially threatening the long-term viability of these populations (Penn 2006). The purpose of this study is to analyze the potential for camu camu to be harvested sustainably based on the status of current wild populations. This project will therefore compare the population structure and regeneration patterns of current camu camu stands to field data collected in the late 1980s in order to examine the effect of increased harvest pressure. To further examine changes in these stands, a remote sensing analysis of the area will complement the field study. To understand the economic aspects of camu camu harvest, data will be collected on the prices at which the fruit is bought and sold.
Camu camu is a small tree or shrub that grows in “oligarchic forests,” dense stands that are dominated by only a few species compared to the highly diverse and heterogeneous forests typically associated with the tropics (Peters et al. 1989b). These stands almost mimic plantations, creating greater potential for sustainable harvesting by lowering costs and travel time, but they maintain the native flora and fauna unlike real plantations or cultivated fields (Peters and Hammond 1990). Commercial interest in camu camu has dramatically increased both nationally and internationally since the discovery of its high vitamin C and antioxidant concentrations (Penn 2006). Camu camu has the highest vitamin C content of any known fruit, around 3000 mg per 100 g of pulp; in comparison, an orange has 53 mg per 100 g of pulp (Ferreya 1959, Zapata and Dufour 1993, USDA database). Increased market interest has the potential to make camu camu harvest economically viable, but could also lead to overexploitation of the resource.
Although the chemical composition of camu camu has been more thoroughly studied, little research exists on the ecology of the plant. The most comprehensive research was conducted in Peru in the 1980s, when Peters and his collaborators studied the camu camu population structure, spatial regeneration patterns of seedlings, and the flowering and fruiting phenology and yield (Peters et al. 1989b, Peters and Hammond 1990, Peters 1990). More recently, Penn (2004) examined the rise of camu camu agroforestry systems that have been encouraged by the Peruvian government through the Programa Nacional de Camu Camu. However, the status of wild populations has not been thoroughly revisited, despite the increase of commercial demand.
Field Site Selection and Justification
Population structure can be used as an estimate of health and regeneration, and could be an indicator of over-harvesting (Leak 1965, Peters 1990). Following the methods used by Peters and Hammond (1990), this study will sample three wild camu camu populations in Peru to collect size-class data. The first site will be at the wild stands located in the Sahua Cocha oxbow lake off the Ucayali River. This area has been one of the largest sources of camu camu, and is also where Peters and Hammond (1990) conducted their research. The second site will be at the wild stands in Muyuy Island of the Tahuayo River, and the third will be located in wild stands outside Iquitos. All three sites were also studied by Penn (2004), and were selected for their proximity to Iquitos, a processing and market center for camu camu.
At each site, camu camu stems will be measured and mapped to the nearest 0.5 meter in ten 10 meter by 10 meter plots. The three sites will act as replicates, and the size class distributions created from the stem width measurements will then be compared to the data collected by Peters and Hammond (1990) in order to see how the camu camu population structure has changed. The spatial mapping of the plots will be analyzed to see if the regeneration of seedlings follows the pattern observed by Peters and Hammond (1990), where smallest seedlings were closest to the water, followed by older cohorts in successive waves. An estimation of the camu camu stem density will also be used to calculate current fruit yield estimates based on Peters and Hammond’s (1990) calculations. While in Iquitos and at each site, information will be gathered on the price of camu camu in local markets and when sold by harvesters to middlemen who transport the fruit. This information will not be statistically analyzed, but will rather provide an economic context for the camu camu harvesting. Additionally, a remote sensing study of the region will be used to complement the field study. LANDSAT TM data has been recorded since the early 1980s, and will be used to show spatial changes in the camu camu stands over time.
Personal Qualifications and Research Collaborations
I have extensive previous experience with independent research, including field research in an entirely Spanish speaking community. For my undergraduate thesis, I spent a summer in Guerrero, Mexico collecting size-class and other data on the ecology of an agave species harvested by local communities for mescal production. Through this study, I gained invaluable experience adjusting to unexpected circumstances and setbacks while navigating a foreign country. I am currently in the process of publishing my results in a scientific journal. I also worked as a research assistant for three years at the Sackler Institute of Comparative Genomics at the American Museum of Natural History. I learned how to organize and analyze data, plan research schedules, mentor younger students, and work independently, tools applicable to the lab or the field.
This project will involve collaborations between Yale F&ES, the New York Botanical Garden (NYBG), the Instituto de Investigaciones de la Amazonia Peruana (IIAP), and Harmless Harvest (a private company interested in promoting sustainable wild harvest). I have a Cullman Fellowship through the NYBG, and have a co-advisor, Chuck Peters, at the Institute of Economic Botany. The IIAP will assist with logistics in Peru, including help in finding a field assistant, in site selection, and in the use of their field stations. Harmless Harvest is a New York City-based company currently using camu camu in their products, and a report on the health of the wild camu camu population will be presented to them based on this research.
- Fly to Iquitos, Peru and travel by boat to the Jenaro Herrera field station.
- Get situated at the field station and hire a field assistant.
- Organize supplies and equipment and teach the sampling technique to my field assistant.
- Meet with the local researchers working with camu camu, especially Miguel Pinedo.
- If time, view the sampling site at Sahua Cocha lake and begin sampling.
- Sampling in Sahua Cocha lake wild stands.
- Travel by boat with field assistant back to Iquitos.
- Sampling in wild stand outside Iquitos.
- Travel by boat with field assistant to Muyuy Island in the Tahuayo River (1 day).
- Sampling in wild stand at Muyuy Island.
- Extra time allotted for field sampling if I fall behind schedule.
- Informal interviews in Belen market in Iquitos about camu camu prices.
- Return to USA.
- Statistically analyze size-class data using R
- Analysis of seedling regeneration patterns
- Remote sensing analysis using GIS
- Write up results to submit to a journal and for the TRI publication and presentation