The Critical Trends Assessment Program (CTAP) is a long-term endeavor, created to monitor the condition of forests, wetlands, grasslands, and streams throughout the state of Illinois. This project seeks to assess changes in ecological conditions as well as to serve as a baseline from which to compare regional and site-specific patterns throughout Illinois. This program is unique because it is the first-ever attempt at a statewide comprehensive assessment. Field surveys for the project started in 1997.

Birds, plants, and terrestrial insects are the major organisms surveyed by CTAP staff in forest, wetland, and grassland habitats. Benthic macroinvertebrates are surveyed in Illinois’ streams.

A total of 150 sites in each of the four major habitat types were selected at the beginning of the project with a goal to survey 30 sites in each habitat each year. To be able to visit and survey all of these sites, we work on five-year cycles. At the end of each five-year cycle, all sites should surveyed. Our first five-year cycle was from 1997-2001, and currently, CTAP is near the end of the second five-year cycle (2002-2006). By the end of 2006, almost all sites should have two visits worth of data.

Summary data are available for download on the web. Researchers may also contact the CTAP coordinator to request plant, bird, and insect data for further analyses. For further information, please visit the CTAP website.

CTAP Staff

Steve Bailey (ornithology)
Connie Carroll-Cunningham(botany)
R. Edward Dewalt(aquatic ecology)
James Ellis (botany)
Rhetta Jack (ornithology)
Brenda Molano-Flores (coordinator; plant ecology)
Greg Spyreas (botany)