Fisheries Data Description

Montana Fisheries Information System (MFISH) 

Restoration Planning: This database can be used to monitor the long-term results of restoration projects, and can also be used to identify streams where restoration could be of most benefit to the fishery.

Data Description: The Montana Fisheries Information System (MFISH) (formerly the Montana Rivers Information System (MRIS) is a database containing information on fish species distribution, supporting data for distribution, and stream information. (the description below for the new MFISH database was provided by Janet Decker-Hess)

"Montana Fish, Wildlife and Parks (FWP) has been working on centralizing the fisheries data on lakes and reservoirs for the last several years.  They started with an old database and collecting new and existing information from FWP, USFS, BLM and USFWS to include and have also linked other existing data sets to the system.  As a result, over 5,000 lakes have been added to our "rivers" system, hence the name change.

The general lakes report includes: location, elevation, mountain range, physical characteristics, ownership and access information.  They also have included bathometric maps and photos when available and a link to the NRIS TopoFinder to take a look at where the lake is.  Data includes: fish distribution and trend information; fish stocking; angler use; genetics and references.  While not all of these fields are complete for all records, they will continue to update the database as they get more information.

While NRIS has always hosted this site, FWP is responsible for the data and the site design.  FWP has recently redesigned their website so they are using the same style for MFISH.  To take a look at what else FWP has to offer, visit their website at: <>.

In addition to adding lakes to MFISH, the biggest change to the system is the use of routed hydrography. Through the National Hydrography Database, a product created by USGS and EPA and now maintained by NRIS, we are now able to designate exact locations of the "from and to" of distribution and survey locations. All of these data are stored in "event tables"; there are no GIS layers created; the data from the table are "linked" to the routed hydrography and displayed spatially.

FWP has "gone live" so what you see on the screen is the most current information that they have gotten from the biologists or from publications.  That is not to say that there may be more recent information out there; they are generally a field season behind as the biologists analyze and process their survey information before the website receives it.  Keep in mind, however, that they are not updating each stream, each year, except on most of our larger rivers and lakes; many streams and lakes have been sampled once and never again.  They have concentrated most of our recent efforts updating the fish distribution, fisheries surveys and genetic testing for native species purity."

An illustrated on-line guide to using MFISH is available here as a Microsoft Word document.  (The on-line guide and this description of the MRIS project was developed by Jennifer Corbin of MFWP). The guide illustrates the use of MFISH by using the upper Clark Fork River as a case study. It includes maps of 

  • Westslope Cutthroat Trout - A comparison of native range with current distribution within the Upper Clark Fork River Drainage  
  • Bull trout core and nodal areas within the Upper Clark Fork River drainage
  • Barriers and bull trout distribution in the Upper Clark Fork Drainage
  • Map of dewatering within the Upper Clark Fork River drainage (detail of Racetrack Creek)
  • Delineation of NWPPC protected areas within MRIS Upper Clark Fork River drainage

Data sets supporting fish distribution include population trend data (population levels in sampled reaches over time), spawning survey data, genetics testing results, fish passage barriers and spawning and adult habitat locations.  Other stream level data include angling use, fisheries resource classification, protected designation, instream flow reservations, stream channel conditions, restoration projects and other data for over 4,500 streams and rivers in the State of Montana. The database is managed and maintained by the Information Services Unit (ISU) of the Fisheries Division of Montana Fish, Wildlife, and Parks and is annually updated through interviews with MFWP, US Forest Service (USFS), US Fish and Wildlife Service (USFWS), Bureau of Land Management (BLM) and tribal fisheries biologists and supplemented with information provided in technical documents and reports.

The purpose of MFISH is to provide Montana fisheries information online in a database that can be queried.  Streams  or lakes of interest can be mapped for viewing and some data sets can be downloaded for use in other analytical applications or for more detailed analysis.  The database is actively maintained and continues to be refined and expanded with new datasets as well as updates to existing information.  Some information highlights one-time assessments, and other information encompasses long-term monitoring.

Fish species distribution is updated annually along with population estimates and sampling information.  Genetic samples are updated several times a year, as the analyses are received from the University of Montana Wild Trout and Salmon Genetics Laboratory.  However, not all field data are entered into the database, and some data sets are restricted to internal access only or distributed upon request (spawning grounds, for example).

The location of sample sites/areas assessed varies; there are many sites throughout the basin. All data have a beginning and ending measure which are marked by the number of stream miles from the mouth.  In addition to stream miles, township location and latitude/longitude (decimal degrees) are also given.  All locations are checked manually with a GIS at the time of data entry.

Time frame-- The duration and frequency of sampling varies from project to project. Database updated annually.

Parameters measured & methods used (each parameter is a clickable link to an online description):

Administrative Data

Biological Data

Physical Data

MFWP Management

Fish Distribution

Stream Barriers

Stream Resource Value

Population Estimates

Dewatered Stream Sections

Protected Areas

Spawning Ground Counts

Instream Flow Protection

Stream Restoration Projects


Land/Water Uses


Angling Use

Stream Channel Conditions

  (At the time of this writing, the categories in red were undergoing updates).
Quality of data -- observations are made by professional fisheries biologists.  The following types of observations are based on visual assessments and professional judgment (as evidenced by the Data Quality Rating for each record) :

  • Species-specific habitat ratings

  • Stream channel conditions

  • Aesthetics

The following types of observations are based on reproducible measurements:

  • Fish Distribution

  • Populations Estimates

  • Dewatered Stream Sections (updated as designated by biologist)

  • Genetics

Data are generally suitable for guiding management; documentation is insufficient to support litigation

Relevant references-- The Fisheries Division of MFWP has an in-house library resource for the Fisheries Division's Helena and regional staff.  It was designed to fill occasional requests from the public and other state and federal agencies.  The Division provides 3 copies of each document MFWP publishes to the Montana State Library for cataloging.  Currently, the reference does not cite a specific piece of information in MFISH; if a water body is cited in a document, that document is shown for that stream.  Plans are to create a better link between data in MFISH and the appropriate reference. 

Contact information: 
Specific questions about the database or data content can be directed to:
Janet Hess-Herbert (MFWP)

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Fisheries-related Drought Reports

Restoration Planning: Might be used in a drought management program to reduce the impacts of drought on fisheries. Development of such a program could be one goal of restoration planning. 

Data Description: Provides summaries of FWP fisheries biologists reports on status and trends in flows, temperature and fisheries. 

Location of sample sites/areas assessed:  Deer Lodge USGS station.

Nature of location information: Based on data at existing USGS station.

Time frame: Reports are filed weekly

Parameters measured & methods used: Biologist notes status and trends in flow, water temperature and likely fisheries condition; fish kills are noted; comments on impacts to access are included.

Quality of data: Visual assessments of professional fisheries biologists.

Relevant references: n/a

Responsible party contact info: For the Upper Clark Fork, Wayne Hadley, fisheries biologist <>


Recommendations for making the info more useful: expand to more sites

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