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GLIN==> Bird Community Index for Assessing Biotic Integrity

Place: U.S. EPA, 77 W. Jackson Blvd., Chicago, IL (Lake Superior
Room, 12th Floor) 
Date/Time: Thursday, December 9, 1999 at 9:30am

Note that the following presentation is the day after the Midwest
Fish and Wildlife Conference in Chicago.  Following the
presentation, there will be a discussion on the feasibility of
developing a similar index in the Great Lakes region.


The Bird Community Index: A Tool For Assessing Biotic Integrity
In The Mid-Atlantic Highlands

Timothy J. O'Connell1, Laura E. Jackson2, and Robert P. Brooks1

1Penn State Cooperative Wetlands Center, Forest Resources
Laboratory, Pennsylvania State University, University Park, PA
16802.  2U. S. Environmental Protection Agency, Office of Research
and Development, Research Triangle Park, NC 27711

     As part of the U.S. Environmental Protection Agency's (EPA)
Environmental Monitoring and Assessment Program (EMAP), we
developed an indicator of biotic integrity based on songbird
community composition. Because songbirds occur in a wide variety
of habitat types, the bird community index (BCI) is intended to
integrate ecological conditions across a large physiographic region
exhibiting diverse land-cover attributes and intensities of human use. 
     Comprised of multiple biological metrics, our indicator is an index
that ranks bird communities according to the proportional
representation of 16 behavioral and physiological response guilds. 
Relative proportions of "specialist" and "generalist" guilds, viewed as
indicators of structural, functional, and compositional ecosystem
elements, determine condition.
     We developed the BCI from 34 reference sites in central
Pennsylvania that represent a gradient of ecosystem condition from
near pristine to severely degraded. Upon satisfactory demonstration
that the BCI could discriminate between categories of ecosystem
condition, we applied the BCI to independent samples of 126 sites
across the Mid-Atlantic Highlands Assessment (MAHA) area.
     Sites were selected using EMAP's probability-based sampling
design, and therefore represent the total land area in the region.  To
verify the BCI's discriminatory properties, we compared the BCI
assessment to independent gradients of landscape disturbance
applied to both the 34 reference sites and the 126 MAHA sites.
     The BCI identified four categories of biotic integrity in the MAHA
area. Our assessment indicated that 16% of the area is in "excellent"
condition, 27% is "good", 36% is "fair", and 21% is in "poor"
condition.  Urban and agricultural sites differ in their respective guild
compositions, but are not separable by overall BCI score.  Forested
sites supporting the two highest-integrity categories contain different
site-level vegetation attributes, but cannot be separated by
landscape-level land-cover composition.  This research also defined
thresholds of land-cover change where significant shifts in BCI
categories were observed.

The full report is available on-line at

For further information, contact Duane Heaton by Dec. 3 or after
Dec. 9, 1999.
Duane Heaton
USEPA Great Lakes National Program Office
77 W. Jackson Blvd. (G-17J)
Chicago, IL  60604-3590
312-886-6399; fax 312-353-2018
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