About Field Sites
Río Cupeyes (CUPE) is an aquatic NEON field site located in southwestern Puerto Rico. Río Cupeyes is managed by the Department of Natural and Environmental Resources (el Departamento de Recursos Naturales y Ambientales, DRNA) under delegation from the Commonwealth of Puerto Rico. This is a 2nd-order wadeable stream and tributary of Río Guanijibo. The watershed is a 4.26 km2 (1053 acre) catchment comprised of old- and secondary-growth subtropical moist and subtropical wet forest. The NEON reach is located in a montane area with steep slopes where landslides may occasionally occur. Although the vegetation adjacent to the stream reach is dense and the stream exhibits a steep gradient, the channel is relatively free of vegetation and is stabilized by large boulders. It is considered a Type 2 Heritage River (Río Patrimonial), a relatively pristine body of water originating within the DRNA-protected State Forest of Maricao (el Bosque Estatal de Maricao). This location is part of the NEON Atlantic Neotropical Domain (D04), which includes the island of Puerto Rico and the southern tip of Florida. The Domain includes two terrestrial field sites and one additional aquatic field site.  
Wet and dry seasons govern climate patterns in Maricao, Puerto Rico. Average precipitation is 50-100 mm (2-4 in.) during the dry season, and precipitation during the wet season exhibits a bi-modal pattern with increasing precipitation during April and May, a typical decrease in June, and increasing precipitation again through October. The average annual precipitation is 1168mm (46 in.) and the average annual temperature is 25°C (77°F). Extreme weather events, such as tropical storms or hurricanes, typically occur between June and December.  
Parent material for Río Cupeyes is serpentinite, derived from ultramafic bedrock.   
The watershed is comprised of shallow, excessively drained serpentine soils derived from ultramafic bedrock, which exhibit low calcium/magnesium ratios; low nitrogen, potassium, and phosphorus; and high concentrations of nickel and chromium. These are generally considered poor agricultural soils, with poor fertility and low water-holding capacity. Interestingly, these clay soils are capable of absorbing unusually large amounts of water, but are unable to retain the moisture due to unique physical properties. Soils remain dry despite an abundance of rain.   
The flow regime is typical of Puerto Rican streams with watersheds comprised of subtropical moist and wet forests. Discharge occurs in strong, seasonal patterns with low flows during the mid- to late- dry season (December through March) and baseflow discharge 2-3 times higher during the annual wet season (May through November). Tropical storms or hurricanes, typically between June and December, may lead to extreme high flow events along this stream. Although much of the channel substrate consists of small particles that are likely to be displaced during high discharge events, large and relatively immobile boulders are ubiquitous along the channel margins. Substrate composition of the stream is a heterogeneous mix of sand, cobble, pebble, large boulder, and large areas of exposed bedrock. 
Forest cover consists of mature, mostly second-growth wet subtropical forest. Dominant tree species in the riparian zone include caimitillo (Micropholis chrysophylloides), white cogwood (Homalium racemosum), roble colorado (Tabebuia schumanniana), mango (Mangifera spp.), and Stahl's stopper (Eugenia stahlii). Undercover growth consists of dense stands of shrubs, small trees, and vines. It is common that thick vine masses descend from the canopy directly into the stream channel. 
Aquatic fauna include many species of fish and freshwater crustaceans, including the freshwater shrimp (Xiphocaris elongata) and the freshwater crab (Epilobocera cinuatifrons). The Maricao Forest and Río Cupeyes watershed are home to many species of amphibians and reptiles, including the Puerto Rican Boa (Epicrates inornatus) and lizards of the genus Anolis. The watershed is also home to a variety of invertebrates, including tree snails (Caracolus caracolla), termites, and stinging wasps. 
Past Land Management and Use
Forest conservation has been recognized as an important resource for the protection of rivers and streams. Wet montane ecosystems were determined to be areas of special value to the public, starting with the Spanish in the late 19th century and later reinforced by U.S. policy for conservation and land management. Puerto Rico experienced a decline in forested area in the early 20th century, to as low as 6% forest cover in the 1940s. Cropland and pasture, primarily coffee plantations, made up 42% of the landscape at this time. Forest cover once again began to increase as many people migrated to the U.S. mainland and coastal cities as a result of Operation Bootstrap's effort to industrialize Puerto Rico. The newly forested regions were primarily private property, and the Department of Natural and Environmental Resources (DNER) has worked to expand protected regions to 15% through land acquisition programs, conservation easements and trainings for sustainable agroforestry practices.
Puerto Rican infrastructure and forest structure are periodically disrupted by hurricanes and wildfires, and other DNER-recognized threats include invasive species, pests and diseases, forest fragmentation and climate change. Hurricanes Irma and Maria in 2017 devastated Puerto Rico's infrastructure, both human and natural. While natural ecosystems are recovering from defoliation, it will take longer for forest structure to be rebuilt. Hurricane Hugo in 1989 caused wide destruction of trees and resulted in altered forest composition and changes in growth rates in affected areas.  
Current Land Management and Use
The Commonwealth of Puerto Rico has delegated management of Río Cupeyes to the Department of Natural and Environmental Resources (Departamento de Recursos Naturales y Ambientales, DRNA). By administrative order of DRNA Secretary Guerrero Pérez, Río Cupeyes was incorporated into the Heritage River Program (el Programa de Ríos Patrimoniales), which protects rivers and streams with natural and relatively pristine attributes. Río Cupeyes passes through the State Forest of Maricao (el Bosque Estatal de Maricao), a high-altitude forest established in 1919 by Governor Arthur Yager. The mission of the DRNA, with respect to the State Forest of Maricao (el Bosque Estatal de Maricao), is to protect, conserve and manage natural and environmental resources for future generations to enjoy and obtain a better quality of life. The goal of conservation in this forest is to minimize habitat loss and fragmentation, with a focus on restoration or conservation of existing corridors.   
NEON Site Establishment
NEON site establishment at CUPE began in January 2015 with a site survey, which generated a site characterization report (NEON.DOC.001648). Reaches were established by June 2015, and a dry run of operations ran through September 2016, when the site transitioned to full operation. The aquatic instrumentation system came online in August 2018. 
 Orden Administrativa 2016 - 07. Programa Ríos Patrimoniales de Puerto Rico. Comisión Estatal de Elecciones, CEE-SA-16-11450.
 Ventosa-Febles, E. A., Camacho Rodríguez, M., Chabert Llompart, J. L., Sustache Sustache, J., & Dávila Casanova, D. (2005). Maricao State Forest, Mayagüez-San Germán-Maricao-Sabana Grande, Puerto Rico. In Puerto Rico Critical Wildlife Areas, pp. 271-275. Commonwealth of Puerto Rico, Department of Natural and Environmental Resources, Bureau of Fish and Wildlife, Terrestrial Resources Division. https://www.yumpu.com/en/document/view/16447049/puerto-rico-critical-wi…-
 Bosques de Puerto Rico: Bosque Estatal de Maricao. (Aug 2008). Hojas de Nuestro Ambiente: Estado Libre Asociado de Puerto Rico Departamento de Recursos Naturales y Ambientales, P-031. drna.pr.gov/wp-content/uploads/2015/04/El-Bosque-Estatal-de-Maricao.pdf
 Department of Natural and Environmental Resources. (2010). Puerto Rico statewide assessment and strategies for forest resources. Government of Puerto Rico. https://estadisticas.pr/files/BibliotecaVirtual/estadisticas/biblioteca…
 Forest Service International Institute of Tropical Forestry. (2019). A comprehensive inventory of protected areas and other land conservation mechanisms in Puerto Rico. United States Department of Agriculture. https://data.fs.usda.gov/research/pubs/iitf/iitf_gtr_50_eng_lowres.pdf
 SanClements, M., Lee, R.H., Ayres, E.D., Goodman, K., Jones, M., Durden, D., Thibault, K., Zulueta, R., Roberti, J., Lunch, C., & Gallo, A. (2020) Collaborating with NEON, BioScience 70 (2), 107-107, https://doi.org/10.1093/biosci/biaa005
 Aquatic Instrument System (AIS) Site Characterization Report: Domain 04. NEON.DOC.001648vC
 U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia. https://mrdata.usgs.gov/mrds/
 PRISM Climate Group, Oregon State University, http://prism.oregonstate.edu, created 4 Feb 2004.
Remote sensing surveys of this field site collect lidar, spectrometer and high-resolution RGB camera data.
This site has a meteorological station located in the riparian area. The met station is outfitted with a subset of the same sensors used at terrestrial sites. Measurements include wind speed and direction, air temperature, barometric pressure, relative humidity, shortwave radiation, and PAR.
Field Site Data
Commonwealth of Puerto Rico
Site Access Allowed
Site Access Details
Please note this area is an active farm. Research activities are limited and must not interfere with farming activites; gates must remain closed at all times to avoid cattle walking out. Start permitting > 6 months prior to scheduled start.
NEON Field Operations Office
NEON Field Operations Address
45 Carr Ochoa
Guanica, PR 00653
NEON Field Operations Phone
San German Municipio
Dominant NLCD Classes
USGS Geology Unit
USGS Geology Name
USGS Lithologic Constituents
Sheared light- to dark-green, serpentinite; chiefly altered harzburgite
USGS Geology Age
Cretaceous to Pre-Cretaceous (?)
Other Domain D04 Field Sites
Other Field Sites in PR