AutoFish is currently available for sale in North America only. For more information contact Dave Knutzen (360-596-9400) or (


Since its implementation the AutoFish System has been used at hatcheries in California, Idaho, Oregon, and Washington. By 2005, over 100 million fish had been Coded Wire Tagged or fin clipped with the AutoFish System.

AutoFish System

02In the Pacific Northwest of the United States, different species and stocks of Pacific salmon (Oncorhynchus sp.) commingle as they migrate towards spawning areas. This often results in mixed-stock fisheries in which some stocks are abundant while others require protection. In fisheries that exploit complex stock mixtures, mass marking and mark-selective fishing emerged as a way to increase the harvest of hatchery fish while protecting natural stocks of concern. Currently, mass marking in this region involves clipping the adipose fin to provide a visual cue that allows differential retention of marked fish while requiring unmarked fish to be released in mark-selective fisheries.

In theory, mark-selective fisheries enable more hatchery fish to be caught while allowing more natural fish to escape to their natal streams and increase the spawning abundance. Mass marking also provides a valuable tool for assessing wild stocks because hatchery origin and natural origin fish can be distinguished as the fish migrate to the ocean, when captured in fisheries, and when they return to hatcheries and spawning grounds.

With about 200 million fish requiring mass marking each year, this program was clearly not feasible with the manual marking and tagging methods that were available in the early 1990's. In response to this need, Northwest Marine Technology (NMT) in cooperation with the Washington Department of Fish and Wildlife, Bonneville Power Administration, and the United States Fish and Wildlife Service began developing a revolutionary new series of machines to automatically inject Decimal Coded Wire Tags (CWT) and excise the adipose fin on salmon and steelhead. Through consistent research and development, these partners created the AutoFish System.04

AutoFish System – An Innovative Approach to Fish Handling

The AutoFish System uses advanced technology to sort and process Pacific salmon and steelhead in a hatchery or fish farm setting. The AutoFish System is a cost effective way to handle juvenile fish rapidly without the use of anesthetic or human contact.

This system can be customized to perform any combination of:

  • Clipping & Tagging
  • Sorting
  • Videos

AutoFish Clipping and Tagging

Enhancement Hatcheries and AutoFish

Mass marking and tagging Chinook salmon, coho salmon, and steelhead reared at enhancement hatcheries is an important tool for managing hatcheries in a scientifically responsible manner. To meet the requirements of the Endangered Species Act (ESA), federal and state mandates, recommendations from independent scientists, and the Hatchery Genetic Management Plans (HGMP), hatchery fish in the Pacific Northwest must have a visible mark or tag that can be used to distinguish them from naturally produced fish as they migrate to the ocean, and as adults in fisheries, at hatcheries, and on the spawning grounds. In the Pacific Northwest of the United States, excising the adipose fin has been selected as the visible mark.

The AutoFish System was developed as an alternative to manual clipping and tagging to help government agencies meet their ambitious marking and tagging goals. The AutoFish SCT6 (sort, clip, tag, six processing lines) is a self-contained mobile unit that has one dual exit sorter and six individual processing lines. This complete system can sort, clip, and tag salmonids from 57 mm to 142 mm without the use of anesthetic and with no human handling.

AutoFish SCT System The SCT6 is designed for large-scale salmon, steelhead and trout tagging and marking programs. It is housed in a 44-foot all aluminum 5th wheel trailer. The SCT6 is economical and efficient to run and reduces fish stress because there is no human handling, no anesthetic and the fish are never completely dewatered during the process.
line This highly efficient and mobile system has demonstrated low mortality (<0.1%), very high clip rates (>99%), and excellent CWT retention rates (>98%).




3 year extended warranty


NMT Manual Tagging Trailer



  • Adipose clip and snout tag or adipose clip only or snout tag only salmonids ranging from 57 mm to 142 mm total length.
  • Over 60,000 fish processed in eight hours with one skilled operator and an assistant.
  • Accurate sorting to within 1 mm of total length.
  • No anesthetic required.
  • Fin clipping rates and CWT placement accuracy superior to that achievable by manual operations.
  • Less costly to operate than manual clipping and tagging systems.


AutoFish Sorting


Screen shot of the AutoFish Sorter touch screen showing a fish being processed and histogram of the current size distribution.


An integral component of Northwest Marine Technology's AutoFish System TM is the AutoFish Sorter. The sorter uses video imaging and fish behavior to accurately measure fish in a stress free environment. The sorter measures the fish within one millimeter of total length and distributes them into size categories.

Touch screen software allows operators to view and change the system configuration. 

Operators can observe individual fish, their lengths, and destinations. A graph shows the current size distribution, allowing the operator to fine tune the system. Tabular data compares the current distribution with the previous day's processing and shows the number of fish distributed into each size category.

Once a fish is measured, the software selects the appropriate size category described by the user. The sorter instructs the diverter to open the appropriate port and the fish is routed to the lines for further processing.



  • Automatically and accurately measures fish within 1 mm total length
  • Sorts fish into size categories
  • Automatically delivers fish of appropriate size range from the holding trough to the individual processing line
  • Sorts up to 10,000 fish per hour


For large scale projects in North America

AutoFish SCT
Three year extended warranty


NMT Manual Tagging Trailer


AutoFish Parts List (pdf)


AutoFish Video

AutoFish System - A New Approach to Fish Handling

TitleAutoFish System - A New Approach to Fish Handling
DateOctober 2003
Fileafs.wmv (9.2 MB)
For a CD with this video, contact our Corporate Office.

AutoFish Video

The California Department of Fish and Game goes high tech to track fish and, hopefully, figure out why salmon populations are in decline.

The Edge of Technology

TitleThe Edge of Technology
DateJune 2008
Filecdfg.wmv (17.6 MB)