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  2. Hydrologic Modeling Community of Practice

WHATIF - Watershed Health Assessment Tools Investigating Fisheries

This model is distributed by EPA as a legacy model, but no user support is available from EPA.

  • Introduction
  • Audience
  • Abstract
  • Applications and Possible Uses
  • Model History
  • Technical Support and Training
  • Quality Assurance and Quality Control
  • Related Sites
  • References
  • Go to WHATIF Model Download Page

Introduction

WHATIF is software that integrates a number of calculators, tools, and models for assessing the health of watersheds and streams with an emphasis on fish communities in the Mid-Atlantic Highland region. The tool set consists of hydrologic and stream geometry calculators, a fish assemblage predictor, a fish habitat suitability calculator, macro-invertebrate biodiversity calculators, and a process-based model to predict biomass dynamics of stream biota (the BASS model). The tools can be used to assess conditions and associated stressors in aquatic ecosystems, to examine causes of impairment, and to forecast ecological outcomes of habitat alterations and fisheries management actions. WHATIF also supports screening analysis, such as prioritization of areas for restoration and comparison of alternative watershed and habitat management scenarios. The toolkit was developed for the Mid-Atlantic Highlands region of the United States in order to support Canaan Valley Institute.


Audience

Engineer, Scientist, Biologist, Researcher, Watershed Manager


Abstract

WHATIF is software that integrates a number of calculators, tools, and models for assessing the health of watersheds and streams with an emphasis on fish communities. The tool set consists of hydrologic and stream geometry calculators, a fish assemblage predictor, a fish habitat suitability calculator, macro-invertebrate biodiversity calculators, and a process-based model to predict biomass dynamics of stream biota (the BASS model).

The software is built upon a database of stream measurements which serve as inputs to the calculators and tools. The calculators and tools vary in complexity, and can take the form of regression-based predictions up to a process based fish population model, the Bioaccumulation and Aquatic System Simulator (BASS). The toolkit allows the user to investigate a location on a stream or river by examining the data that have been collected at the location, and using the data with the calculators to compare actual conditions with predicted or possible conditions.

For example, the Fish Assemblage Predictor might indicate that a stream in this location would likely support a trout population, while the data show that no trout have been observed. Then, the Habitat Suitability calculator could be used to examine the scores for trout to see if an explanation can be found in the current stream conditions. The user could explore what changes could be made to the stream, such as overhanging vegetation or erosion control, to allow trout to thrive. Finally, trout could be "stocked" in the simulation model to see if they persist and how other species are affected.

All of the data, both original observations and user-generated experimental data, are stored in the central database which allows access by any WHATIF tool or calculator. Thus, the output of one tool can become the input of another tool, and this feature is exploited by some calculators and tools with certain kinds of data.


Applications and Possible Uses

  • Watershed health assessment.
  • Prediction of stream hydraulic geometry based on mean annual flow conditions.
  • Prediction of stream hydraulic geometry based on Bankfull flow conditions.
  • Prediction of fish habitat suitability.
  • Prediction of fish assemblage.
  • Prediction of macro-invertebrate biodiversity (EPT and MBII).
  • Simulation of bio-accumulation.
  • Investigate sensitivity of processes and model parameters.
  • Screening analysis, such as prioritization of areas for restoration and comparison of alternative watershed and habitat management scenarios.

Model History

WHATIF was developed in collaboration with the Canaan Valley Institute (CVI) to address aquatic ecosystem management and restoration needs of stakeholders in the Mid Atlantic Highlands region of the United States. WHATIF version 1 was tested by states and nonprofit groups at a CVI Fisheries Management Workshop (December 2005). Subsequent to this usability review, a number of new data, scientific and interface enhancements resulted in the current release, version 2. All WHATIF tools, including a new fisheries stocking, harvest and simplified chemical exposure tool from the Bioaccumulation and Aquatic System Simulator (BASS) model, were developed specifically for this effort. WHATIF version 2 supports both region-wide queries of aquatic ecosystem health and mapping of streams in the Mid Atlantic Highlands as well as stream reach-level investigations of habitat suitability, community dynamics and food web bioaccumulation for mercury, PCBs and dioxin-like compounds.


Technical Support / Training

Currently, there are no planned WHATIF training sessions. Technical questions and requests for application source code can be made directly to the author John M Johnston (johnston.johnm@epa.gov)


Quality Assurance/Quality Control

Most WHATIF scientific models have been reviewed and published in peer-reviewed journals. The WHATIF toolset was further tested by a number of external reviewers prior to release.


Related Sites

  • Food Chain Models
  • FGETS model

References of Published WHATIF Applications and Uses

RASHLEIGH, B., M. J. CYTERSKI, L. M. SMITH, AND J. NESTLERODE. RELATIONS OF FISH AND SHELLFISH DISTRIBUTIONS TO HABITAT AND WATER QUALITY IN THE MOBILE BAY ESTUARY, USA. ENVIRONMENTAL MONITORING AND ASSESSMENT. Springer, New York, NY, 150(1-4):181-192, (2009).

Cyterski and C. Barber. 2006. Identification and Prediction of Fish Assemblages in Streams of the Mid-Atlantic Highlands, USA. Transactions of the American Fisheries Society 135:40-48.

Johnston, J.M. et al. 2006. Watershed Health Assessment Tools Investigating Fisheries WHAT IF version 2.0: A Manager's Guide to New Features. EPA/600/R-06/109. (PDF) (94pp,2.8MB,About PDF)

Mohamoud Y. and R. Parmar. 2006. Estimating Streamflow and Associated Hydraulic Geometry, the Mid-Atlantic Region, USA. Journal of the American Water Resources Association 42:755-768.

Rashleigh, B., R. Parmar, J. M. Johnston, and M.C. Barber. 2005. Predictive habitat models for the occurrence of stream fishes in the Mid-Atlantic Highlands. North American Journal of Fisheries Management 25:1353-1366.

Rashleigh, B., M.C. Barber, M.J. Cyterski, J.M. Johnston, R. Parmar, and Y. Mohamoud. 2004. Population models for stream fish response to habitat and hydrologic alteration: the CVI Watershed Tool. EPA/600/R-04/190  U.S. Environmental Protection Agency, Athens, Georgia.

Barber, M.C. 2003. A Review and Comparison of Models for Predicting Dynamic Chemical Bioconcentration in Fish. Environmental Toxicology and Chemistry. 22(9):1963-1992.

Barber, M.C. 2001. Bioaccumulation and Aquatic System Simulator (BASS) User's Manual Beta Test Version 2.1. EPA/600/R-01/035  U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, Athens, GA.


Model Download

  • Visit the WHATIF model download page.

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Last updated on February 3, 2025
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