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Water: Monitoring & Assessment



Wetlands: Biological Assessment Methods and Criteria Development Workshop, September 18-20, 1996 - Boulder, Colorado

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An overview of EPA's National Wetlands Program - John Meagher
Wetlands monitoring and assessment: New directions in wetlands protection - Doreen Robb Vetter
Biological criteria for wetlands - Susan Jackson
Federal efforts in indicator development - Elizabeth Fellows

Introduction to HGM - E.J. Clairain, Jr
Comparisons and contrasts between functional assessment and other bioassessment approaches - M.M. Brinson
HGM classification - M.M. Brinson
Development and use of reference wetland systems - L.C. Lee
Model development, calibration, and testing - D. Smith

Seeking suitable endpoints: Biological monitoring in streams and wetlands

Applying hydrogeomorphic (HGM) concepts to ecological indicator development - R.P. Brooks
The Mid-Atlantic HGM Riverine Initiative: Where we are and where we hope to go - S.D. Eckles
Report to the City of Pacifica on the 75% design for restoring lower Calera Creek and adjacent wetlands - L.C. Lee

An overview of the hierarchical approach being used by the U.S. EPA's Wetlands Research Program - M.E. Kentula
Can we apply concepts from the development of biological criteria in Ohio streams and rivers to wetlands? - C.O. Yoder and S. Fennessy21 Structural approach for developing wetland biological criteria - M.C. Gernes
Wetland monitoring and development of wet meadow biocriteria for the Platte River in central Nebraska. P. Currier
Developing bioassessment protocols for Montana wetlands - R. Apfelbeck

Birds as bioindicators of wetland condition: Indices, reference sites, and monitoring - P.R. Adamus
Consideration of spatial and temporal scales in development of multi-metric indicators for wetlands: Examples from the Prairie Pothole Region - N. Detenbeck
Wetlands index of biotic integrity: Development of invertebrate and vegetation-based indices in degraded and reference wetlands - J. Helgen and M.C. Gernes
Assessing reconstructed depressional wetlands in the mid-Atlantic states - B.M. Teels and D. Sparling
Development of environmental performance measures for Florida's lower east coast water supply plan - D.R. Swift
Measuring habitat for wildlife potential, and using aquatic invertebrate biomonitoring to evaluate biological integrity in freshwater wetlands - A.L. Hicks

Technical Issues Related to Bioassessment of Wetlands
Integrating Assessment Programs (IBI, HGMA)

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The Clinton Administration's Wetlands Plan calls for the interim goal of no overall net loss of the Nation's wetlands, and the long-term goal of increasing the quantity and quality of the Nation's wetlands resource base. In addition to the Administration's Plan, the main objective of the Clean Water Act (CWA) is "to restore and maintain the chemical, physical, and biological integrity of the Nation's waters" including wetlands. To track our progress towards achieving these goals, the U.S. Environmental Protection Agency (EPA) Wetlands Division is working cooperatively with federal, state, and tribal agencies to improve wetlands biological assessment and monitoring techniques.

Biological assessment techniques are necessary to monitor the biological integrity of wetlands and track the quality of the Nation's wetlands. Based on the CWA, each state establishes water quality standards that consist of (1) designated uses (including aquatic life use), (2) narrative and numeric criteria for supporting each designated use, and (3) an antidegradation statement. By developing biological assessment techniques, states will be able to establish narrative and numeric biological criteria. Based on these criteria, states can determine if waters are meeting their designated uses (e.g., aquatic life use support) and report in CWA §305(b) Water Quality Inventory reports to Congress. With biological assessment methods and biological criteria in place, states can more effectively apply CWA §401 certification to address potential cumulative impacts to watersheds. Biological assessment techniques will also provide data necessary to more effectively target wetland protection and restoration efforts. States and tribes can use biological assessments to identify wetlands impacted by human activities. Based on periodic assessments, states and tribes can evaluate the success of pollution abatement and habitat protection programs at maintaining and improving wetland conditions. States and tribes can also use biological assessment methods to establish performance standards for wetland restoration and mitigation. Wetland biological assessments will also provide data necessary to include wetlands in watershed protection approaches.

In an effort to address the need for the development of wetland biological assessment and monitoring techniques, U.S. EPA's Office of Wetlands, Oceans, and Watersheds and Office of Science and Technology sponsored this workshop to discuss
(1) new ideas and strategies related to wetland biological assessment techniques and criteria development,
(2) the potential incorporation of current functional assessment methodologies, including the Hydrogeomorphic Approach (HGM), into EPA policies and state and tribal programs, and
(3) whether we are ready to take the next steps of developing biological assessment protocols and biocriteria guidance. The workshop was designed to bring together interested individuals in federal, state, tribal, and academic programs, who are currently involved in, or are planning to be involved in, developing biological assessment methods or criteria for wetlands. Wetland managers and scientists must develop the appropriate methods and techniques necessary to measure the integrity of wetland resources if the goals of the Administration's Wetlands Plan and the CWA are to be successfully achieved.

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An overview of EPA's National Wetlands Program

John Meagher, Director, Wetlands Division, Office of Wetlands, Oceans, and Watersheds, U.S.EPA, 401 M St., SW, Washington, DC - 20460
Phone (202) 260-1917; Fax (202) 260-2356; meagher.john@epamail.epa.gov


Fiscal year 1997 is a landmark year for Clean Water legislation. Great strides have been made over the last 25 years in wetlands protection but challenges remain. In August 1993, President Clinton issued the Administration's Wetlands Plan. It incorporated broad input from divergent interests resulting in the development of a comprehensive 40-point plan to enhance wetlands protection while making wetlands regulations more fair, flexible, and effective. The goal of the Plan is to achieve no overall net loss of the Nation's remaining wetland base, to restore wetlands and, where feasible, to increase the quality and quantity of the Nation's wetlands resource base. The Plan streamlines permitting, reduces federal overlap and redundancy, enhances state, local, and tribal participation in wetlands programs, and works cooperatively with landowners. Some accomplishments of the Plan include empowering state, tribal and local government capacity and increasing funding for states and tribes to $15 million in FY95. The next steps include improving techniques to assess wetlands of differing values; increasing authority to state, tribal and local governments through watershed protection; and improving interagency coordination.

EPA is currently working on a wetlands strategic plan to focus our activities over the next five to seven years. We hope to increase the emphasis on integrating wetlands protection with watershed management efforts; invest in capacity building for state and tribal governments; and invest in technical assistance for partnerships in wetlands ecosystem protection.

Progress is being made to improve wetlands protection. From the mid-1970s through the mid-1980s, wetlands were lost at an average rate of 290,000 acres per year. According to recent estimates, from 1982 to 1992, approximately 70,000-90,000 acres of wetlands were lost on non-federal lands each year. By 2005, we hope to begin to increase our wetland inventory. The quality of our remaining wetlands is important. We plan to assess the health and integrity of our wetlands using water quality standards as well as other existing tools. However, there remain many assessment questions. We expect to hear more questions than answers during the course of this workshop. This meeting is a first step toward understanding the status of the science and where we need to go from here.

Wetlands monitoring and assessment: New directions in wetlands protection

Doreen Robb Vetter, Wetlands Division, Office of Wetlands, Oceans, and Watersheds, U.S.EPA, 401 M St., SW, Washington, DC 20460
Phone (202) 260-1906; Fax (202)260-8000; vetter.doreen@epamail.epa.gov


This workshop is the culmination of work that has been going on for several years. We hope that it will provide an opportunity for the exchange of ideas and for discussion. This workshop is a forum to discuss where we are in the ongoing process of developing wetlands biological criteria and assessment techniques, whether or not we are on the right path, and how EPA can help to move the development process along. This meeting is designed as a working meeting. We need to identify scientific and technical gaps in our knowledge and ultimately create a roadmap for the future.

Our long term goals are to increase the quality of our wetlands and to protect wetland integrity or condition using existing tools. EPA's perspective is that the federal government should participate in achieving these goals by providing a framework, promoting consistency among states and tribes, disseminating information, and providing financial and technical support. Tools currently available for protecting wetland quality include biocriteria, antidegradation, water quality certification (§401), NPDES permitting (§402), and the monitoring program (§305(b)).

Biological assessment, monitoring, and criteria exist in a variety of forms. The first generation of wetland assessment techniques developed from a need for rapid wetland functional assessment that was applicable to §404. The next generation of techniques, including HGM, HEP, and other techniques involve more comprehensive monitoring and incorporate reference conditions. How can we build on these techniques? Each existing approach has a niche to fill. Many states are currently monitoring wetlands to assess their wetlands, evaluate the natural range of biological parameters, identify impairment, identify sources of impairment, set restoration goals, and know when restoration has been successful.

The future steps in assessment protocol and biological criteria development include forming a network of wetland monitoring programs. We need to know what to measure and how to measure it, cost effective approaches to monitoring, and we need to know how to set appropriate goals. Data needs to be collected to determine a range of wetland conditions. Reference sites need to be identified and monitoring protocols established. We still need to identify indicators of function and condition. A large body of work has already been conducted. Grants have been issued for indicator development and monitoring development (e.g., OH, MN, MT, TX, MA, NE). Research has been conducted on vegetation, macroinvertebrates and amphibians. We must look at the work that has already been done on certain types of wetlands and on other systems, and put that work into a context that will work nationally for wetlands. The charge to workshop participants is to build bridges, and determine how EPA can best support your efforts to create a roadmap for biological assessment and criteria development.

Biological criteria for wetlands:

Susan Jackson, Office of Science and Technology, U.S. EPA, 401 M St., SW, Washington, DC 20460
Phone (202)260-1800; Fax (202) 260-1036; jackson.susank@epamail.epa.gov


EPA has published technical guidance on the development of biological criteria for streams and wadeable rivers and is working to complete technical guidance on lakes and reservoirs, estuaries and near coastal waters, and coral reefs. In 1997 EPA will support work to develop guidance on large rivers and on wetlands. Development of technical guidance and implementation approaches for wetlands biological criteria will be both technically and programmatically challenging. Technically because wetlands represent a broad range of hydrologic conditions, especially ephemeral wetlands. Programmatically because wetlands programs have traditionally been housed in different offices, sometimes agencies, than water quality monitoring and standards programs.

Biological criteria can be used as a benchmark to measure progress in attaining State water quality goals, specifically a State's progress in achieving the long term CWA goal of biological integrity. Based on the early work done by Dr. Jim Karr who will be addressing this audience later today, biological integrity can be described as "a system that has balance, integrity, and an adaptive community of organisms having a specific composition, division, and functional organization comparable to that of the natural habitat of the region." EPA defines biological criteria as "numerical values or narrative expressions that describe the reference biological condition of aquatic communities inhabiting waters of a given designated aquatic life use; benchmarks for water resource evaluation and management decision-making" (EPA 822-B-96-001). Establishing reference conditions is one of the cornerstones of biological criteria development. Reference conditions provide the basis for evaluating and making judgments on whether a site is impaired or not. Narrative standards must be statements that can be interpreted into numbers.

Biocriteria development is a priority for OST. We are committed to a long-term, stepwise approach to developing and adopting biological criteria into water quality standards. Implementation guidance and case studies illustrating application of the criteria are being developed. Biological criteria will provide a direct measure of wetland quality. They can measure responses to an array of stressors and exposures and can show the impacts of many currently unmeasured chemical stressors. Types of measures include community structure (taxa richness, relative abundance, and dominance), taxa composition (identification, sensitivity, and rare and endangered species), individual condition, and biological processes. Biocriteria are representative of the community condition, they do not rely on a single species measure, they are information rich, and they are predictive. EPA (OST, OWOW, and ORD) and other agencies are involved in a stepwise process of guidance development including technical core workgroup formation (including federal, state, and academic representation), review, feedback, peer review (Science Advisory Board), federal register notice, and document production.
Federal efforts in indicator development:

Elizabeth Fellows, Chief, Monitoring Branch, Assessment and Watershed Protection Division, Office of Wetlands, Oceans, and Watersheds, U.S. EPA, 401 M St., SW, Washington, DC 20460,
Phone (202) 260-7062; Fax (202) 260-7024; fellows.elizabeth@epamail.epa.gov


The Environmental Protection Agency's Monitoring Branch has been collecting water quality data (e.g. STORET, 305(b)) for a number of years but until now has not had a program to evaluate national water quality. The objective of the indicator program is to determine how clean our water is, whether our programs are working, and whether we are making progress toward our goals. The Intergovernmental Task Force on Monitoring (ITFM), which first met in January 1992, determined that the following steps are necessary to meet the objectives of the indicator program:

  1. identify goals
  2. identify indicators
  3. identify methods
  4. identify assessment techniques
  5. report information

The EPA now has four means of providing water quality information:
(1) the 305(b) monitoring reports which will now be completed every five years,
(2) the environmental indicators report,
(3) the Surf Your Watershed internet tool, and
(4) the Index of Watershed Indicators (IWI) (renamed from the National Watershed Assessment Program (NWAP)). The primary means of assessing water quality is the 305(b) report to congress which includes voluntary, state, and tribal reprots of water quality.
The last 305(b) report concluded that approximately 60% of assessed national waters are in good condition. However, only nine states reported water quality information for wetlands in that report.

The first Environmental Indicators Report, which is the environmental equivalent of an economic indicators report, came out this year. The water quality objectives that will help us meet our goals are: to reduce and prevent pollution loadings, to conserve and improve ambient conditions, to support designated uses, and to conserve and enhance public and ecosystem health. Of the eighteen indicators in the report, ten are state-developed indicators, six are from federal agencies, and two are from private organizations. The wetland indicator in the report is historical wetland loss by state (based on FWS and USDA data).

Other programs that the Monitoring Branch uses to evaluate the national water quality include Surf Your Watershed and the IWI. Surf Your Watershed is a tool that is available on the internet and, although it is not yet complete, it is continually being updated. The first IWI report, expected early next year, will describe the water quality of 2,149 watersheds in the U.S. .

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Introduction to HGM: M.M. Brinson, E.J. Clairain, Jr., L.C. Lee, and D. Smith

Ellis J. "Buddy" Clairain, Jr., Leader, Wetlands Research Team, U.S. Army Corps of Engineers, Waterways Experiment Station, 3909 Halls Ferry Road, Vicksburg, MS - 39180-6199
Phone (601) 634-3774; Fax (601) 634-4016; clairae@ex1.wes.army.mil


The session on the hydrogeomorphic classification and approach (HGM) will provide a broad introduction to HGM and to the differences between HGM and other techniques. HGM was developed in 1990 by the U.S. Army Corps of Engineers' Waterways Experiment Station in response to the need for an assessment technique that would satisfy Corps regulations. An interagency coordination committee was formed in conjunction with interdisciplinary working groups. HGM was designed to be a compromise between utilizing comprehensive data and relying on the expertise of scientists. The objectives of HGM were to ensure that it is applicable to §404 and that it focuses on functions, not values. Previous assessment methods either required long-term monitoring, which was time and resource intensive, or relied on the subjectivity of experts.

HGM is a two-phased approach. The object of the initial Development Phase is to classify the wetland and to identify reference wetlands. To do so, an interdisciplinary assessment team (A-team) is utilized. This phase begins with the classification of wetlands into regional wetland subclasses based on hydrogeomorphic factors and the development of a functional profile of the subclass. The profile describes the physical, chemical, and biological characteristics of the subclass, identifies which functions are most likely to be performed, and identifies attributes that influence each function. The HGM approach is based on reference wetlands and the expertise of the A-team. The Development Phase also includes the development and calibration of assessment models.

Phase two, the Application Phase, utilizes protocols that were created by the A-team to collect and analyze data. This phase is conducted by field staff such as regulators, managers, and/or consultants and includes a characterization of the wetland ecosystem, application of assessment models, calculation of functional indices, and analysis.

Comparisons and contrasts between functional assessment and other
bioassessment approaches
- M.M. Brinson, E.J. Clairain, Jr., L.C. Lee, and D. Smith

Dr. Mark Brinson, Professor, East Carolina University, Greenville, NC 27858-4353
Phone (919) 328-6307; brinsonm@mail.ecu.edu


The hydrogeomorphic approach (HGM) is an ecosystem assessment approach which (1) classifies wetlands by geomorphic setting, water sources, and hydrodynamics for the purpose of controlling for natural variation, (2) clearly defines functions relevant for the class, including the logic for the relationship between structure and function, and (3) develops reference standards for each class from least altered, relatively natural wetland sites. HGM differs from bioassessment approaches in several ways, in part due to its initial design to support §404 of the Clean Water Act through project-by-project application within a particular wetland assessment area. By using functions as the "currency" for assessment of condition, the HGM approach provides a platform upon which to apply recent research findings in the form of hydrologic, biogeochemical, plant community, and animal habitat studies. The functions also can be translated effectively into goods and services (flood protection, water quality, etc.) that society considers valuable. HGM detects ecosystem change (i.e., before and after an impact or restoration) and provides standards toward which restoration projects can be designed and by which they can be evaluated.

Bioassessment approaches focus on the composition of biological communities as a measure of biotic integrity. Its application to wetlands has shifted from strictly aquatic organisms (e.g., macroinvertebrates and diatoms) associated with surface water to woody and herbaceous plant community components that often receive only seasonal inundation, the situation in many wetlands. Bioassessments rely little on the physical characteristics of the ecosystem (water flows, soil conditions, nutrient status), but rather more on the response of the biotic community to changes in these characteristics.

HGM and bioassessment approaches both assume that relatively unaltered ecosystems are functioning optimally over a suite of functions characteristic for the subclass. Relatively unaltered conditions should yield the highest scores using either assessment method. Both approaches also require consensus on the least altered condition and both are reference-based.

HGM classification - M.M. Brinson, E.J. Clairain, Jr., L.C. Lee, and D. Smith

Dr. Mark Brinson, Professor, East Carolina University, Greenville, NC 27858-4353
Phone (919) 328-6307; brinsonm@mail.ecu.edu


The purpose of the hydrogeomorphic (HGM) classification system is to classify wetlands based on hydrologic and geomorphic characteristics that are responsible for maintaining many of the functional aspects of wetland ecosystems. It relies almost exclusively on geomorphic, physical, and hydrologic descriptors. This system controls for some of the natural variation in wetlands and helps assessors distinguish between natural and anthropogenic variation. This classification method addresses the need to view wetlands as components of landscapes. There are seven proposed HGM classes for wetlands: riverine, depressional, slope, organic soil flats, mineral soil flats, estuarine fringe, and lacustrine fringe. This broad classification is designed to focus attention on how wetlands differ in their functions based on the driving forces of geomorphic setting, water source, and hydrodynamics. When dealing with regional subclasses, the nationwide classification is applicable in principle but not necessarily in detail.

HGM classification does not replace other classification schemes (e.g., NWI, ecoregions, Natural Heritage programs). HGM classification can utilize existing regional classifications and nomenclature, especially those that place an emphasis on hydrogeomorphic descriptors. Once the HGM classification is developed for a region, the biotic components become critical in the assessment of ecosystem condition.

Development and use of reference wetland systems - M.M. Brinson, E.J. Clairain, Jr., L.C. Lee, and D. Smith

Dr. Lyndon C. Lee, Wetlands Ecologist, L.C. Lee & Associates, Inc., National Wetland Science Training Cooperative, 221 1st Avenue West, Suite 415, Seattle, WA 98119
Phone (206) 283-0673; Fax (206) 283-0627


Reference, in the context of hydrogeomorphic (HGM) functional assessments, is used as a basis for comparing two or more wetlands of the same subclass. Reference puts functional assessments on a local or regional basis. Reference allows use of a relative scale providing better resolution and reflecting the "art of the possible." Reference establishes the range of variability within the regional HGM subclass and establishes a regional standard of comparison.

A "reference domain" includes all wetlands within a defined geographic region that belong to a single HGM subclass. The reference domain is developed by (1) defining the HGM subclass based on project requirements and (2) defining the geographic region. The reference domain will range from disturbed to relatively undisturbed wetlands. Domain can be defined by ecoregion, extent of continental glaciation, political boundaries, or watershed boundaries.

"Reference wetlands" are wetland sites within the reference domain that encompass the known variation of the subclass and are used to establish the range of functions within the subclass. Reference wetlands are selected by: determining the HGM class and subclass, defining the geographic limits of the wetland, consulting local experts and local maps, locating sites representing different successional stages, sampling enough wetlands for diversity (minimum of 20), visiting a suite of potential sites, and completing a profile of the wetlands.

"Reference standard sites" are sites within a reference wetland data set from which reference standards are developed. These sites are those judged by an interdisciplinary team to have the highest level of functioning.

"Reference standards" are conditions exhibited by a group of reference wetlands that correspond to the highest level of functioning across the suite of functions of the subclass. "Site potential" is the highest level of functioning possible given the local constraints. "Project target" is the level of function identified for a restoration or creation project and is based on reference standards or site potential and is consistent with project goals. "Project standards" are performance criteria and/or specifications used to guide the restoration or creation activities towards the project target.

Model development, calibration, and testing - M.M. Brinson, E.J. Clairain, Jr., L.C. Lee, and D. Smith

Dan Smith, Ecologist, U.S. Army Corps of Engineers, Waterways Experiment Station, 3909 Halls Ferry Road, Vicksburg, MS 39180-6199
Phone (601) 634-2718; Fax (601) 634-4016; smithr1@ex1.wes.army.mil


The hydrogeomorphic approach (HGMA) includes hydrogeomorphic classification. The objective of an HGMA model is to assess the ability of a wetland to perform a specific function relative to similar wetlands in a region. In order to meet that objective, an HGMA model must be: sensitive to a range of anthropogenic stressors commonly placed on wetland systems, insensitive to the natural variation of wetland systems, capable of determining a loss or gain of function, and capable of identifying the cause of the loss or gain of function. HGMA models are developed by a team of experts and are applied by field staff. The components of an HGMA model include: the variables or physical, chemical, or biological attributes of a wetland, the variable index or number or category that defines the condition of a variable relative to reference standards, and the functional capacity index which quantifies the capacity of a wetland to perform a function relative to other wetlands from a regional wetland subclass in a reference domain.

Developing an HGMA model includes defining functions, identifying and documenting the variables, and verifying and validating the model. Functions must be defined so that they are testable during the validation process. Calibration of the variable index involves sampling a range of reference wetlands, determining a range of variables with reference standard sites, and setting the variable index of the maximum in the range of 0 to 1.0. Model verification is an iterative process that includes determining whether the output is reasonable. Model validation is necessary at both the variable index and at the functional capacity index levels.

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Dr. James R. Karr

Seeking suitable endpoints: Biological monitoring in streams and wetlands -J.R. Karr

Dr. James R. Karr, Professor of Fisheries, Zoology, Environmental Health and Public Affairs, Box 352200, University of Washington, Seattle, WA 98195
Phone (206) 685-4748; Fax (206) 543-2025; jrkarr@u.washington.edu


The development of multimetric biological indexes has advanced both the theory and practice of biological monitoring. For streams, such indexes shifted a historical imbalance, where monitoring chemical parameters was relied on to protect the "physical, chemical, and biological integrity of the nation's waters." Properly used, multimetric biological indexes can (1) detect degradation of living systems, (2) diagnose the likely causes of degradation, (3) identify management actions that can halt or reverse degradation, and (4) track living systems to find out if management efforts to restore degraded sites have succeeded. Biological monitoring is cost effective and improves our ability to protect waterways and their associated resources.

The longer history of wetland protection has its analogies with stream protection. Partly to convince the skeptical, wetland scientists have claimed that wetlands can be "delineated" and stressed the importance of their "functions" to society. Yet replacement or "mitigation" of specific functions did not retain the integrated values or complex roles played by natural wetlands. Attention to hydrological or soil criteria did not detect biological degradation. The developing HGM methodology is an important advance that will formalize and broaden the functional approach. But is it broad enough? Does it give enough attention to measured biological endpoints? Just as chemical criteria alone have not protected streams, functional criteria may not be adequate to protect wetland landscapes. The goal for wetland protection programs, like that for stream programs, should be to evaluate the impact of human activity on wetland condition. Chemical and functional endpoints do not tell managers what they need to know about the condition of living systems; direct measurements of biological attributes -- elements as well as processes -- are essential.

Wetland delineation and classification, the major activity of past wetland protection programs, should be balanced (replaced) by efforts to measure the effects of human actions on wetland condition. To successfully use biological criteria in wetland management, one must (1) select measurable biological attributes that furnish relevant and reliable signal about the effects of human activities, (2) develop sampling designs and protocols for accurately measuring those attributes (3) define analytical procedures to extract and interpret relevant patterns in the sample data, and (4) communicate those results to policy makers and citizens so that all stakeholder communities can contribute to public policy.


Living systems provide a signature of disturbances that is understandable and convincing to the public. The biological perspective needs to be at the core of communication with the public about environmental policy. We need to remember that the political economy must be balanced with political ecology.

In wetland assessment, there may be an overemphasis on classification currently. Classification should guide monitoring and assessment, not define them. All of the differences in wetlands and wetland types may not be relevant to our management goals. Additionally, there has been a shift in classification recently towards abiotic characteristics (e.g., HGM) which may not be the only important characteristics for classification.

Limitations of HGM:

  • Defining functions is limiting; we do not understand the attributes of wetlands well enough to define every function that will be known or valued in the future
  • HGM does not define/assess biological endpoints well
  • HGM needs to be tested for its effectiveness
  • The HGM approach should be a hypothesis and should not be a federal policy
  • HGM does not use any empirical values to describe human influences

Biological systems are complex. We need metrics which shift in relation to an ecological gradient (the ecological "dose-response" curve). Reference sites that run from pristine to severely impacted are necessary in order to develop ecological dose-response curves where human impact is the "dose" and the ecological response is the "response."

Factors affecting biotic integrity:

  • water quality
  • habitat structure
  • energy source
  • flow regime
  • biotic interactions

Biological monitoring began with biotic indices to classify stream organisms. At the time, the main impact of concern was sedimentation. When chemicals became the contaminants of concern, toxicology and dose response curves became useful. These approaches did not account for the synergistic effect of contaminants but indicator species proved to be useful to show the impacts of combinations of stressors. Changes in abundances of species turned out to be less helpful than expected because of the natural variability in abundance and the difficulty in separating natural variations from human-influenced abundance changes. We now know that diversity indices are more useful. Multivariate statistics ignore important signals such as rare species.

Indices of biotic integrity combine elements and processes of biological systems including species composition, community structure, and individual health. The ten metric Benthic Index of Biotic Integrity (BIBI), for example, includes metrics such as taxa richness, EPT (Ephemeroptera, Plecoptera, Trichoptera) richness, and percent impervious surface.

Strengths of the Benthic Index of Biotic Integrity (BIBI) Metrics:

  • use measurable attributes that have been tested and respond to a range of human influences
  • provide data from which a relevant pattern can be extracted
  • results are accurate and easily communicated to the public

Problems to avoid in biological criteria development:

  • assuming habitat is independent of human activities
  • expecting simple chemical-biological water quality correlations
  • examining the entire gradient of human influence
  • utilizing an ecoregion or subregion focus
  • probability-based sampling
  • collecting more data than necessary
  • always measuring all seasons

Be careful when using the term "community" because it is used in two different ways. A community can either refer to an assemblage of organisms or can be used to describe a hierarchical level in ecology (e.g., individual, population, community). For IBIs, use the word "assemblage" instead of community.

Future directions:

  • Plants and invertebrates are good indicators; amphibians are also appealing; however, birds are problematic
  • Use terms such as taxa richness, trophic structure, and species composition instead of abundance, biomass, density, number, and productivity


How can you determine the difference between natural disturbances and anthropogenic disturbances?

The magnitude and nature of change from human activities is significantly larger than that resulting from natural disturbances.

Can IBI be used to predict the results of an impact to a wetland?

Yes. IBIs can be used to make such predictions but only at the 75-80% confidence level.

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Applying hydrogeomorphic (HGM) concepts to ecological indicator development - R.P. Brooks, D.H. Wardrop, L. Bishel-Machung, T.J. O'Connell, M.T. Gaudette, D.J. Prosser, and C.A. Cole

Robert P. Brooks, Penn State Cooperative Wetlands Center, Forest Resources Laboratory, Pennsylvania State University, University Park, PA 16802
Phone (814) 863-1596; Fax (814) 863-7193; rpb2@psu.edu


Collectively, human activities have produced a range of stressors, such as sedimentation, hydrological modification, and habitat fragmentation causing wetlands to become disturbed. These stressors are associated with specific ecological indicators. For example, birds respond to changes in landscape patterns that occur on a regional scale, such as habitat fragmentation. Amphibians respond to habitat disturbance, but at a more local scale. They are impacted by acidification due to atmospheric deposition and coal mine drainage. Similarly, wetland plant communities respond predictably to hydrological modifications and changes in sedimentation rates.

We have used a suite of ecological indicators to assess the condition of a set of reference wetlands in Pennsylvania. The reference wetlands were classified into eight subclasses, using a regional HGM key. The classes (and subclasses) are: depression (isolated, riparian), riverine (headwater floodplain, mainstem floodplain), slope, impoundment (beaver, human), and fringe. These HGM subclasses differ in their respective soil characteristics, plant communities, hydrologic and water quality signatures, sedimentation rates, and wildlife habitat potential. They also span a disturbance gradient from relatively pristine, to moderate, to severely degraded. The recommended assessment process is to: (1) establish a landscape context and condition for the wetland in question using an HGM key and rapid field assessment techniques; (2) compare the results to the expected range of characteristics and measures of stressor-specific indicators for reference wetlands; and (3) use these findings to improve decisions for assessing condition and impacts.

The Mid-Atlantic HGM Riverine Initiative: Where we are and where we hope to go - S.D. Eckles

S. Diane Eckles, Ecologist, U.S. Fish and Wildlife Service, 177 Admiral Cochrane Drive, Annapolis, MD 21401
Phone (410) 573-4553; Fax (410) 224-2781


The Mid-Atlantic HGM Riverine Wetlands Initiative is a regional effort involving developing models for one or more subclasses of riverine wetlands located on the Inner Coastal Plain of Delaware, Maryland and Virginia. The mid-Atlantic Initiative is a cooperative venture between researchers associated with a university and a Federal research institution, a consulting firm, and Federal and State agency representatives that work in regulatory and non-regulatory programs. An Assessment Team (A-Team), consisting of state and federal agency representatives, was formally assembled within the last seven months. The A-Team is using a draft guidebook for riverine wetlands along small stream bottoms (orders 1 through 3) located on the mid-Atlantic Inner Coastal Plain as a template to conduct tasks leading to finalization of a regional guidebook. The final regional guidebook may include models for one or more subclasses of riverine wetlands on the mid-Atlantic Inner Coastal Plain.

There are a variety of challenges involved in this effort that can be classified into science-based, geopolitical, and spatial-temporal. However, the establishment of reference wetlands and development of models for one or more subclasses of wetlands can have application to programs other than Federal and State wetland regulatory efforts. While HGM is not developed to quantify or assess cumulative impacts, combining the current regional HGM effort with a study to address cumulative impacts within a portion of the mid-Atlantic region will eventually provide robust data sets for the conservation of wetland ecosystems.

Report to the City of Pacifica on the 75% design for restoring lower Calera Creek and adjacent wetlands - L.C. Lee

Dr. Lyndon C. Lee, Wetlands Ecologist, National Wetland Science Training Cooperative, 221 1st Avenue West, Suite 415, Seattle, WA 98119
Phone (206) 283-0673; Fax (206) 283-0627


In conjunction with the construction of a wastewater treatment plant, the City of Pacifica California proposed to relocate lower Calera Creek, presently a ditched stream on a former quarry site, and restore a riparian zone and associated riverine and depressional wetlands. The primary goal of the wetland restoration was to improve riverine ecosystem functions including hydrology, water quality, plant community maintenance, and habitat/faunal support. A secondary goal of the restoration project was to create habitat for the endangered San Francisco Garter Snake and provide optimal conditions for colonization by prey species.

Hydrogeomorphic assessment (HGMA) was used as the basis for assessing the impact of the proposed project and designing Calera Creek wetland restoration. Data from a "reference set" of 56 wetlands, in the same class as those at Calera Creek, focused on hydrology, biogeochemistry, plant community maintenance, and habitat/faunal community maintenance. Profiles of wetland functions were developed to be used as templates for restoring the wetlands.

In the restoration design, the stream channel will be changed from ditched flow to a naturally configured channel placed in a relatively wide floodplain. The riparian corridor will be vegetated with a mosaic of native plant species found at the reference wetlands. Habitat will be constructed for the endangered San Francisco Garter Snake and its prey species in the form of two ponds and will be vegetated with grasses, shrubs, and trees.

There will be no net loss of wetland area or function as a result of the Calera Creek Project. Using HGM, the projected level of function provided by the proposed restored wetlands, 5 years after restoration, was assessed. Fifteen wetland functions were measured and compared with conditions currently existing at the Calera site. "Attainable reference" wetlands served as a template against which wetland functions at Calera Creek were measured both before and after restoration. The level of function for all 15 functions increased, with two exceptions. The function to "maintain spatial habitat structure" remained the same because five years is not enough time for ecosystem level spatial structure of the habitat to increase. The nutrient cycling function also remained at the same level because not enough time would have elapsed for ecosystem level nutrient cycling processes to increase. A "functional capacity unit" (FCU) was used (Smith et al., 1995) which represents the level of wetland function multiplied by the acreage on which the function is performed. FCUs were tabulated for (a) existing conditions at Calera Creek, (b) conditions five years after the restoration, and (c) the change in FCU as a result of the restoration. After the wetland restoration, the level for all functions except two would be "lifted" and those two will show an increase with the passage of more than five years time. The area over which these functions are performed will also increase by 13%. Hence, the restoration of wetlands at Calera Creek would result in a net increase in both wetland area and function. * abstract has been shortened for the purposes of these proceedings.

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An overview of the hierarchical approach being used by the U.S. EPA's Wetlands Research Program - M.E. Kentula

Mary E. Kentula, Program Leader, U.S. EPA - NHEERL, 200 S.W. 35th Street, Corvallis, OR 97333
Phone (541) 754-4478; Fax (541) 754-4716; kentula.mary@epamail.epa.gov


An overview of the hierarchical approach being used by the U.S. EPA's Wetlands Research Program to sample populations of wetlands will be presented. The approach provides information on individual wetlands, subgroups within the population, and the entire population. Information on the entire population can be used to describe the status of the population in the landscape. Examples of results from studies in Oregon will be given.


Comprehensive reference-based, multi-metric wetland research involves (1) setting priorities and objectives, (2) designing a monitoring and restoration program, and (3) reporting results. Though this is a regional example, other labs have used similar approaches and have achieved similar results. The objectives of the hierarchical approach were to:

  • characterize and monitor natural and mitigated wetlands to provide information for management decisions
  • document direct and indirect wetland losses
  • determine the effects of land use changes on wetlands

Sampling was hierarchical in design both spatially and temporally. The majority of the wetlands were characterized on a five-year rotational basis, though some were characterized continuously. National Wetlands Inventory (NWI) maps were used initially to select suitable sites and were later used to divide the sites into classes. Ninety-seven sites were studied in four land-use classes (agriculture, city, residential, undeveloped). Continuous hydrological data was used and each area was defined by ecoregion, Cowardin class, and political unit.

The majority of the mitigated sites are permanent open-water wetlands. Changes in plant species richness in mitigated and natural sites were recorded. Most of the species lost from both natural and mitigated sites were native taxa. There was a greater loss of native species in mitigated wetlands. Fifty percent of all plant species found in the 97 study sites were non-native species. Forty percent of the wetlands were lost, mostly due to urbanization.

Can we apply concepts from the development of biological criteria in Ohio streams and rivers to wetlands? - C.O. Yoder and S. Fennessy

Chris Yoder, Ohio Environmental Protection Agency, Division of Surface Water, 1685 Westbelt Drive, Columbus, OH 43228
Phone (614) 728-3382; Fax (614) 728-3380

Siobhan Fennessy, Ohio Environmental Protection Agency, Division of Surface Water, 1800 WaterMark Drive, Columbus, OH 43216-1049
Phone (614) 644-2152; Fax (614) 644-2329; sfenness@central.epa.ohio.gov


Ohio EPA incorporated biological criteria ("biocriteria") into the Ohio Water Quality Standards (WQS) regulations in February 1990 for inland rivers and streams. Biocriteria are based on measurable characteristics of fish and macroinvertebrate assemblages and are used to assess the biological integrity of surface waters. This represents a significant progression in Ohio's Water Quality Standards, which had previously relied on a chemical approach in assessing surface water quality. While traditional chemical and toxicity test techniques remain essential elements of the program, the addition of biocriteria has significantly broadened the scope of surface water assessment and protection in Ohio. Biocriteria for rivers and streams were derived by utilizing the results of sampling conducted at least impacted regional reference sites. This design is based on an operational definition of biological integrity, represented by the biological performance of the natural habitats of a region. Further organization was accomplished using Omernik's ecoregions of which Ohio contains five. Fish and macroinvertebrate data were obtained using standardized methods from more than 350 reference sites. These results were used to establish attainable, baseline expectations within the framework of a stream classification system (tiered aquatic life use designations) as defined in the Ohio WQS. Biocriteria provide the impetus and opportunity to recognize and account for natural, ecological variability in the environment. One important result is being able to account for differences between ecoregions, river and stream sizes, and aquatic life use designations. Biocriteria function primarily as an ambient assessment tool and are the principal arbiter of aquatic life use attainment or non-attainment for Ohio's rivers and streams. They have profound influence on how regulatory requirements are derived and applied.

The fundamental approach used to develop stream biocriteria is being applied to wetlands in Ohio. Potentially ecologically meaningful indicators are being tested to determine if they possess the sensitivity necessary to discriminate between least-impacted and impaired wetlands. Methodologies to assess vegetation, macroinvertebrate and amphibian communities are under development and will be standardized to ensure they are relatively rapid, repeatable and transferable to others conducting biological monitoring. Sampling will be organized primarily at the community and ecosystem (i.e., process) scale. Indicators being tested include a vegetative biocriteria, the floristic quality assessment index (FQAI) which is comparable to a Hilsenhoff biotic index, using species richness and tolerance values for flora. As with streams, biological integrity for wetlands will be operationally defined, based on least-impacted reference sites. Reference sites have been selected based on hydrogeomorphic setting, degree of impact, and proximity to active Ohio EPA stream reference sites. The methodologies employed and any derived biological criteria may vary as a function of HGM class. A regional framework may also be employed to discriminate expectations for wetland attainable condition. The implementation of a regional framework is a long term process that requires a relatively high number of reference sites.

Biocriteria will be used to define the attainable condition for a class of wetlands in a given region and, as in the streams program, will be used to develop a wetland classification system in which the highest attaining class will be protected to the fullest extent while restoration or enhancement goals are set for more impaired systems. Biocriteria are essential to define the level of protection and restoration goals necessary to meet swimmable and fishable goals for aquatic systems.

Structural approach for developing wetland biological criteria - M.C. Gernes and J. Helgen

Mark C. Gernes, Monitoring and Water Quality Division, Minnesota Pollution Control Agency, 520 Lafayette Road N., St. Paul, MN 55155
Phone (612) 297-3363; Fax (612) 297-8683; mgernes@wq.pca.state.mn.us

Dr. Judy Helgen, Monitoring and Water Quality Division, Minnesota Pollution Control Agency, 520 Lafayette Road N., St. Paul, MN 55155
Phone (612) 297-7240; Fax (612) 297-8683; judy.helgen@pca.state.mn.us


The Minnesota Pollution Control Agency recognizes the need to develop biological criteria to support its long term water quality monitoring strategy and the refinement and implementation of wetland water quality standards. An approach to establishing multi-metric biological indices based on reference condition is the basis of this presentation. This multi-metric approach is conceptually similar to biological criteria for rivers and streams based on the fish and invertebrate communities. Two field projects aimed at developing biological criteria for depressional wetlands have been completed. First, in the reference wetland project, the biological community was sampled in 32 minimally impaired wetlands to establish the reference condition. Several invertebrate metrics and an amphibian metric were proposed from this reference work. In the second project, the sensitivity of the proposed metrics was tested in 20 wetlands known to be influenced by storm water discharge in urban areas and by agricultural practices in rural areas.

Six reference wetlands were also sampled for comparison with the impaired wetlands, to allow for modifications in the invertebrate metrics and to develop initial vegetation metrics based on the emergent fringe community. Standardized sampling methods using activity traps and dipnetting for invertebrates and relevant techniques for the vegetation community have been established and will be presented. Proposed metrics and resulting biological indices based on the invertebrate and vegetative communities will be presented in a separate talk. The next step in this development process is to test a simplified biological sampling approach that may be suitable for nontechnical persons.

Wetland monitoring and development of wet meadow biocriteria for the Platte River in central Nebraska - P. Currier

Paul Currier, Executive Director, Platte River Whooping Crane Maintenance Trust, Inc., 2550 Diers Ave., Suite H, Grand Island, NE 68803
Phone (308) 384-4633; Fax (308) 383-4634


Riverine wetlands and sedge meadows are some of the most important habitats in the Platte River landscape in central Nebraska. Protection of their biological values and ecosystem function is especially important for cranes, waterfowl, and other avian species that use the river as a spring migration stop and staging area. During the past few years, an attempt has been made to develop a risk assessment for the middle Platte River basin to address the ecological values of the river and its adjacent habitats, and potential risks to its integrity. A conceptual floodplain model was developed to integrate the effects of river and land management on river channel, wet meadow, backwater, and riparian habitats, as well as on key species, including cranes, wetland vegetation, amphibians, and nesting grassland and woodland birds. In order to evaluate the ecological links described in the model, the Platte River Trust and other researchers have developed preliminary biocriteria that include hydrologic monitoring, avian habitat use, wetland plant indicators, and the distribution and abundance of aquatic organisms. Preliminary results are presented, including the use of the IHA "Indicators of Hydrologic Alteration" methodology (Richter et al., 1996), studies concerning the distribution and characterization of wetland meadows, and studies dealing with the distribution and habitat selection of summer-nesting avian grassland species. Future data needs and applications to other watersheds are also discussed.

Developing bioassessment protocols for Montana wetlands - R. Apfelbeck, L. Bahls, M. Shapley, J. Gerritsen, M.Barbour, J. Stribling, D. Charles, and F. Acker

Randy Apfelbeck, Water Quality Specialist, Montana Department of Environmental Quality, Monitoring and Data Management Bureau, 2209 Phoenix Ave., P.O. Box 220901, Helena, MT 59620-0901
Phone (406) 444-2709; Fax (406) 444-5275; rapfelbeck@mt.gov


Eighty wetlands were sampled throughout Montana from April through September of 1993 and 1994 to develop wetland bioassessment protocols. Wetlands were sampled for water column and sediment chemistry, macroinvertebrates, and diatoms. Hydrologic, geologic, and climatic data were collected from maps and existing databases. In order to partition the variability, a wetland classification system is being developed to group reference wetlands by ecoregion and hydrogeomorphology. Water column chemistry and the biological components are being used to refine the wetland classification.

A multi-metric approach is being used to develop a macroinvertebrate index to assess wetland water quality. Number of taxa and percent dominance metrics were the most responsive to stressors. Preliminary results indicate detection of impairments caused by metals, nutrients, salinity, sediment and fluctuating water levels. The ability to detect water quality impairment using the macroinvertebrate index decreased for wetlands that were ephemeral, located at high elevations, or where the water column was alkaline or saline.

Diatom assemblage data was analyzed using TWINSPAN for two-way indicator analysis. Seven TWINSPAN groups of wetland sites were identified subjectively based on similarity in diatom flora. The multivariate technique used for understanding relationships among diatom assemblages and environmental characteristics was Canonical Correspondence Analysis (CCA). The environmental factors that correlated most closely with diatom assemblage composition using CCA were conductivity, pH, and total phosphorus. Inference models were developed to quantitatively infer pH, conductivity, and total phosphorus from diatom assemblages. TWINSPAN and CCA were being used to refine the wetland classification and to detect water quality impairments.

Future objectives include developing bioassessment protocols using vegetation and to assimilate vegetation into the wetland classification. The inference values generated from diatom assemblages may be useful for developing bioassessment indices and to apply to sediment core assemblages to reconstruct historical changes in water quality to determine if changes have occurred.

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Birds as bioindicators of wetland condition: Indices, reference sites, and monitoring - P.R. Adamus

Paul R. Adamus, Adamus Resource Assessment, Inc., 6028 N.W. Burgundy Drive, Corvallis, OR 97330
Phone (541) 754-7092; Fax (541) 753-4507; adamusp@ucs.orst.edu


Birds can complement plants, aquatic invertebrates, and other organisms as bioindicators of wetland quality, particularly at the landscape scale. Wetlands selected as reference sites for mitigation and permitting activities could, under some conditions, be used in the development and application of biocriteria and HGM reference standards that reflect avian habitat needs. I describe and illustrate specific decisions associated with using birds and avian reference sites in regional monitoring of wetland quality. These include choice of appropriate scale, application of meaningful avian indices, definition of an appropriate number of HGM subclasses, selection of relevant reference sites and variables for HGM models, and implementation of sufficient monitoring effort.


Birds are useful indicators because they are relatively easy to sample, spatially and temporally integrative, valued by the public, and some reference databases for birds currently exist. Problems with using birds as indicators are that (1) their presence alone is not conclusive, (2) it is difficult to link birds to stressors, (3) they require repeated site visits, and (4) there are species differences in detectability. Using birds as bioindicators requires repeated visits by skilled observers to all microhabitats, with point counts of three or more minutes each, and the use of taped vocalizations for cryptic birds (e.g., rails and bitterns).

Consideration of spatial and temporal scales in development of multi-metric indicators for wetlands: Examples from the Prairie Pothole Region - N. Detenbeck

Naomi Detenbeck, Research Ecologist, U.S. EPA, 6201 Congdon Blvd., Duluth, MN 55806
Phone (218) 720-5617; Fax (218) 720-5539; detenbeck.naomi@epamail.epa.gov


Standardization of indicator measurements for streams has focused on maximizing the signal:noise ratio. Strategies applied include (1) choosing a sampling window to minimize temporal variability, (2) integrating collection of samples across multiple habitats or sampling only within the most productive habitat (e.g., riffles), (3) stratifying or standardizing collections by pool/riffle units, (4) constructing metrics based on the relative proportion of functional guilds rather than individual species, and (5) creating additive indices comprised of individual indicators that are consistently sensitive to different combinations of stressors. However, spatial and temporal variation are integral characteristics of wetland ecotones, and biota have evolved life cycles and responses to specific scales of variability. Stratification, window selection, and smoothing techniques for wetland indicator measurements must be chosen so as to maximize ecological information obtained (e.g., choosing sampling periods corresponding to life cycle bottlenecks) as well as to minimize background noise. In some cases, measurement of variance (min/max, heterogeneity) may be more ecologically significant than measurement of system averages.

Wetlands index of biotic integrity: Development of invertebrate and vegetation-based indices in degraded and reference wetlands - J. Helgen and M.C. Gernes

Dr. Judy Helgen, Monitoring and Water Quality Division, Minnesota Pollution Control Agency,
520 Lafayette Road N., St. Paul, MN 55155
Phone (612) 296-7240; Fax (612) 297-8683; judy.helgen@pca.state.mn.us


Biological metrics for multi-metric indices of wetlands water quality have been developed based on two field-based projects. The Reference Wetlands Project funded by MN LCMR and US EPA showed that invertebrate richness was sensitive to water quality parameters. Out of this work, several invertebrate metrics were developed for the WIBI, or Wetlands Index of Biotic Integrity. A metric representing evidence of successful amphibian reproduction was included. In 1995, the Wetlands Assessment Project, funded by US EPA, tested whether the invertebrate metrics could detect impairment in sets of stormwater and agriculture-influenced wetlands in relation to reference sites, and began the development of vegetation metrics. An earlier talk will give the framework of these projects. The present talk will focus on the metrics and indices that have come out of this work. The invertebrate metrics for the WIBI have been modified and will be presented.

Eight metrics for vegetation are proposed for a vegetation WIBI. Reference sites were well separated from impaired sites by the invertebrate and vegetation WIBI scores, while combining both WIBI scores provided the sharpest separation of reference and impaired sites. Having two separate WIBI multimetric approaches available, one based on vegetation and one on invertebrates, will allow a wider seasonal index period for wetland assessment.

Assessing reconstructed depressional wetlands in the mid-Atlantic states - B.M. Teels and D. Sparling

Billy M. Teels, NRCS, Wetland Science Institute, Patuxent Research Center, Snowden Hall,11400 American Holly Drive, Laurel, MD 20708-4014 Phone (301) 497-5938; Fax (301) 497-5911; billy_teels@nbs.gov

Don Sparling, National Biological Survey, Patuxent Wildlife Research Center, Snowden Hall,11400 American Holly Drive, Laurel, MD 20708-4014
Phone (301) 497-5723; Fax (301) 497-5744; don_sparling@nbs.gov


Wetlands are complex living ecosystems, broadly held to be valuable because of the many functions they perform. In recognizing those values, Congress has authorized a number of Federal and State initiatives to protect and restore wetlands. Although hundreds of thousands of acres of wetlands have been restored or reconstructed, there has been little monitoring conducted on these wetlands to assess their progress towards healthy, fully functioning ecosystems. The few individual monitoring studies that have been conducted indicate that the quality of most completed projects is inconsistent and that improvement of restoration techniques is needed. Furthermore, not only is there insufficient understanding about the factors that affect the rate and success of wetland development following reconstruction, there is a lack of standardized methods for monitoring this development.

The understanding of health in other ecosystems has advanced beyond that of wetlands. For instance, several theoretical frameworks and methodologies have been created in stream ecology to assess the health of streams. One of the more commonly used tools for stream ecosystems is the Index of Biological Integrity (IBI). This index measures various biological aspects (metrics) of an ecosystem such as species richness, the proportion of various guilds (e.g., trophic, tolerance, and breeding), the presence of certain indicator organisms, or specific components of morphology, physiology or behavior to assess the health of the ecosystem.

The underlying premise of the index is that the organisms inhabiting the ecosystem are reliable and measurable indicators of that ecosystem's health. Several studies have shown promising results using fish and macroinvertebrate data to calculate IBI scores indicative of the health in streams. Wetlands and streams, although sharing some species in common, are sufficiently different to prevent a direct transfer of IBI, however; the same principles of biological integrity should apply and there is no reason to believe that an index similar to IBI cannot be developed for wetlands.

Before an IBI-like index can be used to assess health in mid-Atlantic reconstructed wetlands, it first must be developed. The objectives of this study are to:

  • Inventory a series of reconstructed depressional wetlands that were created or rebuilt under partnership restoration projects located on the Eastern Shore of Maryland.
  • Using this inventory as a baseline, develop a series of metrics similar to those developed for IBI. It is intended that the IBI and inventory baseline will become a reference for future wetland inventories in the mid-Atlantic region.
  • Validate and compare these metrics by relating them to each other and to physical and chemical factors that are traditionally accepted as measures of wetland health. The goal of this objective is to determine how metrics based on different components of the wetland relate and identify those metrics which most reliably reflect wetland health and can be measured within budgetary and time constraints typical of most monitoring efforts.
  • Develop a set of sampling protocols that will help standardize methods used in the data gathering and analysis of these metrics.

The overall study is a cooperative effort between the NRCS, Wetland Science Institute and the NBS, Patuxent Wildlife Research Center with scientific support and funding coming from each agency. Efforts are focused on 24 recently reconstructed wetlands located in agricultural settings within the Eastern Shore of Maryland and Delaware. Each of the cooperating scientists have developed initial protocols for sampling specific components of the wetland ecosystems, including: hydrology, soils, water chemistry, vascular plants, macroinvertebrates, amphibians, birds, and mammals. The coinvestigators have trained teams of technicians, graduate students, and volunteers on the use of the protocols to survey the selected wetlands. Auxiliary studies have been designed to determine the adequacy of sampling. After evaluation of the first year's survey data, the scientists will propose metrics that appear to discriminate differences in the quality of the reconstructed wetlands and be indicative of wetland health. Additional studies will be conducted to determine relationships among the proposed metrics and identifying physical and chemical factors that may influence the biological integrity of the reconstructed wetlands. To account for annual and seasonal variation in climate and progressional development of these recently developed wetlands, the study is designed for at least three years.

Development of environmental performance measures for Florida's lower east coast water supply plan - D.R. Swift, C.J. Neidrauer, and N.C. Krishnan

David R. Swift, Senior Environmental Scientist, Lower East Coast Planning Division, South Florida Water Management District, West Palm Beach, FL 33406
Phone (407) 687-6703; Fax (407) 687-6442


The South Florida Water Management District is currently developing a lower east coast water supply plan to guide public policy as it relates to protecting and enhancing the water resources of South Florida. The study area includes natural areas such as Lake Okeechobee, the St. Lucie and Caloosahatchee River estuaries, the Water Conservation Areas (WAS), Everglades National Park (ENP), Florida Bay, and Biscayne Bay as well as agricultural and urban areas.

The plan was initiated in 1992 and involves a large scale public participation process. A regional computer model, the South Florida Water Management Model (SFWMM), simulates current and future surface and ground water conditions within the study area as a method to evaluate proposed water supply alternatives. Analyses of current and future (year 2010) base case simulations indicate that significant water supply problems will result in the projected population growth is allowed to occur without corresponding improvements to the regional system. These analyses identified the need to improve the volume, timing and distribution of water delivered to ENP and Florida Bay, improve hydroperiod within Lake Okeechobee's littoral zone, and reduce the number of flood control discharges from the lake to downstream estuaries.

Over 40 environmental performance measures were developed to evaluate data generated by the SFWMM. These performance measures represent hydrological surrogates for measuring how well a particular water supply alternative meets the environmental objectives of the plan for each identified natural area. Evaluation tools include development of

  • wetland hydroperiod and surface water ponding difference maps,
  • wetland stage hydrographs and stage duration curves at key water management gages as compared to "Natural Systems Model" targets,
  • flow/salinity criteria to protect downstream estuaries,
  • calculation of flow volumes across model grid cell flow lines, and
  • minimum water level criteria to protect wetland peat and marl soils.

These tools, criteria and performance measures have been successfully applied to evaluate numerous model runs and water supply alternatives. The majority of government agencies and local interest groups have accepted this methodology and approach.

Measuring habitat for wildlife potential, and using aquatic invertebrate biomonitoring to evaluate biological integrity in freshwater wetlands - A.L. Hicks

Anna L. Hicks, Project Wetland Scientist, The Environmental Institute, Blaisdell House, University of Massachusetts, Amherst, MA 01003-0820
Phone (413) 545-0952; Fax (413) 545-2304; ahicks@tei.umass.edu


The Environmental Institute at the University of Massachusetts has been responsible for developing two separate wetland evaluation methodologies: a) WEThings: a habitat assessment protocol using landscape and wetland indicators to predict possible presence of wetland-dependent amphibians, reptiles, and mammals of New England; and b) the application of aquatic invertebrate biomonitoring in freshwater wetlands to measure biotic integrity.

Until now, no methodology existed that allowed agencies to predict potential habitat for wetland-dependent amphibians, reptiles, and mammals. WEThings serves to meet this need in the New England states. The methodology is based on an extensive literature review of measurable habitat characteristics conducted for each of the listed species, some of which are rare, threatened, or endangered. Detailed summaries of the literature base were compiled for each species and serve as the basis from which predictive models were produced. WEThings, which incorporates a software program, enables researchers, consultants, and state and federal regulatory agencies to better predict potential habitats for these species.

Invertebrates are becoming increasingly important as a measuring tool to monitor ecological integrity of water bodies and have proven value in assessing the health of streams and rivers. Only recently has research commenced on the application of an aquatic invertebrate bioassessment protocol suitable for wetland conditions. Research was conducted into the application of a rapid assessment methodology using aquatic invertebrates along with suitable metric indicators to derive an Invertebrate Biotic Index, accompanied by a Habitat Assessment that incorporated key landscape and wetland indicators. A summary graph provided an assessment of wetland ecological integrity, and whether impact was due to habitat degradation or some other cause, such as chemical pollution.

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The participants devoted the last day of the conference to two main topics of discussion. The first topic centered around the technical issues related to bioassessment of wetlands. The second topic related to potential mechanisms for integrating bioassessment methods (e.g., IBI) and functional assessment methods (e.g., HGM). The participants also recommended a series of "next steps" for the EPA's effort to promote wetland bioassessment programs.

Technical Issues Related to Bioassessment of Wetlands


In theory, scientists could use any taxa for assessing the biological integrity of a wetland if they have a good assessment framework and sampling methods. However, some taxa react more strongly to stressors and require fewer resources to sample. In addition, the scope of the bioassessment program will influence the selection of taxa. When assessing the biological integrity of a single wetland, scientists may decide to only sample taxa that spend their entire lives within or near the wetland. Stressors from outside the wetland, such as habitat fragmentation, could contribute to the decline of birds and other mobile taxa. Therefore, scientists can use mobile species for assessing biological integrity at a watershed or landscape scale.


Several state representatives wanted to know how many metrics they should include in an index of biological integrity. In general, scientists will need more metrics to assess wetlands with rich biota than to assess wetlands with fewer taxa. Although there is no magic number of metrics to include, Jim Karr recommended that states should include enough metrics to represent each of the following categories:

  • species/taxa composition,
  • species/taxa richness,
  • ecological structure/process/function (display guilds), and
  • individual health.

Though using different terminology, these categories are similar to those presented by the Intergovernmental Task Force on Monitoring Water Quality (Figure 1) (ITFM 1995).

Scientists do not have to distribute metrics evenly between these four areas. Workshop participants suggested that changes in structure (e.g., species richness, composition) come earlier than changes in functional groups as a habitat becomes increasingly degraded. The changes in species richness and composition are more easily detected earlier in the degradation of an environment because of the loss of sensitive and specialized biota. Generally, habitat specialists will disappear before habitat generalists and tolerant species will disappear before intolerant species. To detect the degradation of a wetland, scientists will have more difficulty using functional organization (e.g., bottom-feeder, scavenger, predator) than species richness because it requires more detailed information. While scientists have used functional organization metrics for stream fish assemblages, they have not applied them to more complex assemblages such as macroinvertebrates. Research to understand the functional relationships of the overwhelming number of invertebrates is incomplete. Thus, scientists may decide to emphasize community structure of invertebrates and include more of those metrics in the overall index.

Workshop participants also suggested that researchers could detect "healthy" conditions by measuring the number of taxa and the presence of sensitive taxa. Both sensitive and tolerant taxa would survive in "healthy" wetlands, which would result in many taxa present. In a degraded wetland, the sensitive taxa would not be present and the tolerant taxa would increase in abundance. Conversely, researchers could detect impaired conditions by detecting decreased taxa diversity and increased abundance of tolerant assesmblages.
Biological Assessment

Figure 1:

Organizational structure for attributes that should be incorporated into biological assessments (ITFM 1995).

Participants suggested that states and tribes avoid making their metrics too specific while selecting and calibrating metrics. Likewise, they should avoid developing a new metric and sampling method for each wetland type. Instead, they should develop a set of standard sampling methods and metrics. States will likely apply a metric statewide because of limited resources. The state or tribe could then calibrate the standard metrics to different wetland types by using reference wetlands of each type.

Combining Metrics

Several workshop participants asked if they should combine metrics into an overall index of biological integrity. Jim Karr suggested that researchers should include enough metrics to observe changes in each of a wetland's dominant families and trophic levels. However, scientists should be careful when combining trophic levels and major families into a single metric such as the EPT metric, which is commonly used for stream monitoring. When families respond similarly to a stressor, combining them into a single metric may be helpful for scientists. If they respond differently, however, combining them into a single metric may cloud the signals. Figure 2 provides the responses of Ephemeroptera (E), Plecoptera (P), and Tricoptera (T) to a hypothetical stressor. In this example, the three respond differently to the stressor and separating them into individual metrics may provide more helpful information than combining them into a single metric.
graph of level of disturbance vs number of taxa

Figure 2:

A hypothetical example Ephemeroptera (E), Tricoptera (T), and Plecoptera (P) reactions to increasing habitat disturbance.

Diversity Indices

Several participants recommended that researchers avoid using diversity indices for bioassessments. Stream scientists developed some indices, such as the Hilsenhoff Biotic Index, to detect organic pollutants and sediments in streams, and they may not be appropriate for wetlands. In addition, this type of index clouds the data and hides important trends because it overemphasizes the middle of the spectrum. As an alternative, workshop participants suggested that researchers use multimetric indices and focus some metrics on the middle of the spectrum and focus other metrics on the most tolerant and sensitive species (Figure 3). If the "tolerant" class begins to dominate the biota, it may be a signal of severe degradation within the wetland. Similarly, the disappearance of the "sensitive" class could be an early sign of human disturbance. Researchers do not need to understand fully why the organisms are tolerant or sensitive to use them as indicators. It is also important to recognize that many responses of assemblages to increasing habitat disturbance will not be linear.
graph of level of disturbance vs. abundance

Figure 3:
Hypothetical reactions of different assemblages to increasing habitat disturbance

Infrequently Flooded Wetlands

Many participants were deeply concerned with the lack of research on "drier-end" wetlands. Most bioassessment programs have focused their research on permanently and semi-permanently inundated wetlands. Few bioassessment programs have focused on ephemeral wetlands or those that lack standing water for most of the year. Besides receiving little research, the ecologically-important "drier-end" wetlands are receiving the brunt of the development pressures. Further research is clearly needed to develop bioassessment methods for "drier-end" wetlands.

Next Steps

The workshop participants agreed that there is a nationwide deficiency in wetland monitoring. To help fill this void, the participants suggested that the EPA should continue to promote wetland assessment methods and to take a more active, leadership role. The conference participants suggested that the EPA should pursue the following actions.

  • Provide Technical and Financial Support - Besides providing increased funding to states and tribes, the EPA could assist existing programs by providing technical expertise. Several states stressed the need for additional technical support by EPA regions.
  • Increase Cooperation and Communication Between States and With Tribes - Several states suggested that the EPA could help foster cooperation and communication between neighboring states and with tribes. EPA regions could share available information and open lines of communication between governments. Participants also stressed the need to more effectively share study designs, techniques, and results. States or tribes should also attempt to share reference sites with others in the same ecoregions.
  • Increase Outreach to Managers and the Public - Participants suggested that the EPA develop more outreach material for managers and the public. Educating managers about the importance and many applications of bioassessment techniques is essential. Developing bioassessment techniques that can be easily explained to the public is also important.
  • Establish Bioassessment Workgroup - Participants suggested that the Wetlands Division organize an interagency workgroup to produce preliminary guidance for wetland bioassessment programs. The workgroup would include state, federal, and academic scientists and would focus on issues such as selecting reference wetlands, classifying wetlands, selecting and testing metrics, and selecting and testing analytical procedures.
  • Explain Strengths and Limitations of Assessment Methods - In recent years, many scientists have developed independent functional and biological assessment methods. The conference participants suggested that EPA and Corps should identify the best assessment methods and describe their strengths and limitations. Several participants felt that they need rapid functional assessments more urgently than bioassessment methods.
  • Examine Representation of Wetlands in 305(b) Reports - On a broader scale, the participants suggested that the EPA should reevaluate the 305(b) program as it relates to wetlands. Is the EPA asking the right questions? How can the EPA improve 305(b) for wetlands? How can states and tribes improve designated uses for wetlands?
  • Develop Bioassessment Methods for "Drier-end" Wetlands - Participants stressed the need for more bioassessment research in drier-end wetlands.

Integrating Assessment Programs (IBI, HGMA)

After discussing the technical issues related to wetlands bioassessment, the conference participants examined how to integrate functional assessment methods (i.e., HGMA) and bioassessment methods (i.e., IBI).

Integrating HGM Classification and Bioassessment Methods

Several state and federal representatives are using the HGM classification scheme to group wetlands in their biomonitoring programs. By separating wetlands into distinct groups (e.g., riverine, depressional, etc.), states can better distinguish between variations in wetland caused by different habitat conditions from variations in biota caused by human activities. In addition, a state can calibrate its index of biological integrity for each wetland type. Instead of creating many different indices, states could develop one or two indices of biotic integrity and then use the classification scheme to calibrate the indices to different wetland types.

Conversely, states could use biological parameters to refine their HGM classes and subclasses. For example, they may not need to distinguish between two types of riverine wetlands if the biota of the two wetlands are very similar. In contrast, researchers may need to separate the two types of riverine wetlands if they have two distinct biological assemblages.

HGM Assessment Methods (HGMA) and Bioassessment Methods

Integrating HGMA and bioassessment methods is a more challenging prospect that deserves further attention. State managers and the public will be reluctant to accept two distinct assessment programs due to demands on resources and the potential for duplicating efforts unless they are well integrated and understood.

HGMA and bioassessment methods are being developed for different regulatory programs and therefore are different in their approach to characterizing wetlands. The Corps of Engineers is developing HGMA primarily as a rapid, functional assessment methodology to improve Clean Water Act §404 permitting and mitigation decisions. HGMA attempts to characterize a broad range of wetland functions related to hydrologic processes, biogeochemical processes, and habitat quality. In contrast, other federal and state agencies are developing rapid bioassessment methods to quantify the biological integrity or condition of wetlands to refine state water quality standards and biological criteria (Clean Water Act §303). The bioassessment methods take direct measurements of the biota and often combine measurements (or metrics) into an overall index of biological integrity. Physical and chemical measurements of study sites typically accompany biological measurements to help identify causal effects. Although bioassessment programs are time and resource-intensive during their development, they have valuable applications when completed. With rapid bioassessment protocols, states and tribes can track wetland condition, identify impairment and diagnose sources of impairment, prioritize protection and restoration efforts, and establish restoration goals and set performance standards for mitigation projects.

Despite being developed for different purposes, the HGMA and bioassessment methods share several important similarities that states and tribes could use to integrate the two efforts. Opportunities to integrate the two programs include the following:

  • Reference Sites - Both HGMA and bioassessment programs establish a network of reference sites and use them as benchmarks of "healthy" conditions. The workshop participants suggested that sharing reference sites can be a first step of integrating the two efforts. The participants also recommend that the HGMA and bioassessment programs coordinate use of the term "reference," which is currently used differently in each method.
  • Focus on Biota - As part of its functional assessment, HGMA includes the assessment of a wetland's plant community, detrital biomass, habitat structure, invertebrate community, and vertebrate community. Eventually, states and tribes may incorporate rapid bioassessment protocols into HGMA to strengthen its biological components.
  • Testing and Validation - Both the functional and biological assessment methods require extensive testing and verification before states and tribes can apply them effectively. Many states are building their wetland bioassessment methods from their experiences with streams, rivers, and lakes. While somewhat similar, wetlands are sufficiently different from other aquatic habitats to prevent the direct transfer of sampling protocols, metrics, and indices. States and tribes must test the assessment methods to identify appropriate indicators, establish reference conditions, and calibrate metrics and indices. Similarly, HGMA must be tested and validated b efore states can apply it effectively. For some wetland functions, HGMA relies on e stimations rather than on direct measurements As a result, HGM scientists must first show that the estimati ons and professional judgement are good proxies for direct measurements. Also, HGM scientists must show that important wetland functions were not overlooked. Biological assessment can serve to validate the HGM approach by providing measures of wetland c ondition to compare with HGM overall assessments of function.

Literature Cited

Intergovernmental Task Force on Monitoring Water Quality (ITFM). 1995. The Strategy for Improving Water-Quality Monitoring in the United States. Technical Appendixes. Final Report for the Intergovernmental Task Force on Monitoring Water Quality. (available on the Internet at h2o.usgs.gov/public/WICP/rept.html) [BROKEN]

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