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Eileen H. Helmer

Research Ecologist
International Institute of Tropical Forestry
USDA FS - RMRS, 240 West Prospect Road
Fort Collins, CO 80526
United States
Current Research
  • Tree successional dynamics and diversity across landscapes reforesting after large-scale clearing
  • Remote sensing of tropical forests
  • Interactions among the drivers of tropical forest productivity and species composition
Research Interest
  • USDA Forest Service Forest Inventory and Analysis Program in the Caribbean
  • Forest inventory to study the dynamics and diversity of tropical forest trees across landscapes
  • Characterization of tropical forest types, age, structure and change with satellite imagery
  • Tropical montane cloud forests and humid alpine systems



  • Oregon State University, Ph.D., Forest Ecology, , 1998
  • University of Minnesota, M.S.C.E., Environmental Engineering and Sciences, , 1987
  • University of Illinois, B.S., Ecology, Ethology and Evolution, 1984
Professional Experience
  • Ecologist,  US Environmental Protection Agency, Region 5,  1990 - 1993
  • Environmental Engineer,  U.S. Environmental Protection Agency, Region 5,  1988 - 1989
Professional Organizations
  • Member,  American Geophysical Union,  2004 - Current
  • Member,  Association for Tropical Biology and Conservation,  2000 - Current
  • Member,  Ecological Society of America,  1997 - Current
Featured Publications
Other Publications
Research Highlights

Long-Term Seasonality of Greenness in Tropical Forest

Year: 2020
Seasonal patterns of forest greenness (termed phenology) help guage forest productivity and health. Mapping changes in these patterns with satellite imagery can locate where forests are most affected by hurricanes or drought. This research is refining algorithms for, and mapping, long-term phenology...

Neotropical Cloud Forests to Lose What Most Defines Them: Clouds

Year: 2019
In as few as 25 years, climate change could shrink and dry 60-80 percent of Western Hemisphere tropical montane cloud forests.

Automated monitoring of tropical deforestation made easier

Year: 2018
New algorithm permits automated tropical forest monitoring back to the 1970s and allows more frequent observations since the year 2015

A Synthesis of How Multispectral Satellite Imagery Can Support Inventories of Greenhouse Gas Emissions from Tropical Forest Clearing and Regrowth

Year: 2015
Human clearing, logging, and burning of tropical forests accounts for at least 19 percent of annual human-caused emissions of carbon dioxide to the atmosphere, which is more than the global transportation sector. Multispectral satellite imagery is the timeliest and most accessible remotely sensed da...

Nitrogen and Phosphorus Content in Forest Floor Litter is Elevated in a Tropical Landscape Recovering from Deforestation

Year: 2014
Fallen leaf chemistry provides a window into the various and often complex factors affecting the availability of nutrients to trees. Both nitrogen and phosphorus content in forest floor litter is current greater in Puerto Rico's novel tropical forests than it was before deforestation when presumably...

Mapping avian habitat characteristics using cloud-cleared satellite image mosaics

Year: 2010
Forest age, vertical structure, disturbance For studies of wintering habitat for the endangered Kirtland's Warbler, scientists from the Forest Service, Colorado State University, and other collaborators showed for the first time that forest vertical structure can be mapped with a time series of sate...

New Study Leads the Way to Detailed Mapping of Tropical Rain Forest Types

Year: 2012
Tropical tree communities mapped for Trinidad and Tobago with satellite imagery