Coded Wire Tag Injectors

Northwest Marine Technology makes three Coded Wire Tag injectors:

Mark IV Tag Injector and Quality Control Device (QCD)

Mark IV Coded Wire Tag injector

Mark IV Tag Injector

This is the workhorse of Coded Wire Tag injection and uses spools of wire. The Mark IV Tag Injector can be used to inject up to 600-800 tags/hour and is designed for projects with many thousands of fish to tag. It cuts a tag from the spool and injects it into the specimen. The Mark IV Tag Injector can inject half length (0.5 mm), standard length (1.1 mm), one and a half length (1.6 mm) or double length (2.2 mm) tags. It can be used with either a Head Mold to position the specimen or a needle support tube for freehand tagging.

Mark IV Tag Injector specifications (pdf)

Learn more about Head Molds

Learn about selecting needles for the Mark IV and Multishot Injectors

The QCD is a small tunnel through which fish are scanned for CWT. Shown with legs.

Quality Control Device (QCD)

The Quality Control Device (QCD) is used with the Mark IV to verify that a tag has been injected. The fish is dropped into the QCD after tagging, and fish with a tag will be diverted from those without a tag. The Mark IV can be used without a QCD, but the QCD requires a Mark IV to operate.

Quality Control Devices specifications (pdf)

Handheld Multishot Injector

Note: Effective April 1, 2022, NMT will no longer be manufacturing Multishot Injectors (https://www.nmt.us/multishot-injector-discontinued/). Multishots will be available for rental in North America. 

Handheld Multishot Coded Wire Tag injector set up with a spool of tag wire.

Handheld Multishot Coded Wire Tag injector set up with a spool of tag wire.

The Handheld Multishot Injector can be used to achieve tagging rates of several hundred tags per hour, and is suitable for moderate sized projects or when power is not available. The Multishot cuts a tag from the spool of wire and injects it into the specimen. The Multishot can inject standard length (1.1 mm), one and a half length (1.6 mm) or double length (2.2 mm) tags. It can not be used to inject half length tags. Like the Mark IV Injector, the Multishot can be used with Head Molds to assist with tag placement.

Handheld Multishot Injector specifications (pdf)

Learn more about Head Molds
Learn about selecting needles for the Mark IV and Multishot Injectors

Single Shot Tag Injector

Single Shot Coded Wire Tag injector with accessories

Single Shot Coded Wire Tag injector

The Single Shot Injector is used with Precut Sequential Coded Wire Tags. It is suitable for smaller-scale tagging projects in which a couple of hundred tags may be injected in a day. Precut Tags are loaded into a hollow needle and a spring-loaded plunger is used to push the tag into the specimen.

Learn more about Precut Tags (pdf)

Selecting Needles for the Mark IV and Multishot

As you prepare for tagging, you will need to select Coded Wire Tag injection needles. A clean, sharp needle of the proper length and style is necessary for effective tagging. The type of injector, the species, and the size of the fish, and the target tag location will determine the appropriate needle.

Mark IV Coded Wire Tag Injectors use 2.5 inch (6.35 cm) and 3.5 (8.9 cm) injection needles. The shorter needle is for use with head molds. The longer needle is for use with the needle support tube.

Multishot Injectors use a 1.55 inch (3.94 cm) Coded Wire Tag injection needle. This needle can accommodate a head mold or a needle support tube.

Comparison of etched and non-etched needlesEach of the three Coded Wire Tag injection needles is available as either “non-etched” (pictured on the left) or “etched” (pictured on the right). A non-etched needle has a constant outside diameter (0.0225 in, 0.57 mm) from its base all the way to the beginning of the beveled tip. The etched needle is reduced to a smaller outside diameter (0.0185 inch, 0.47 mm) for about 0.3 inches (0.76 cm) from the beginning of the bevel.

The etched needle has a greater likelihood of bending with fish with tougher tissue and with “body” tagging such as cheeks of smallmouth bass, the scutes of sturgeon, and the rostrum of paddlefish. The non-etched needle in a needle support tube is often the better combination for penetration and tag placement in these types of tagging.

For further information on Needles and Head Molds refer to the Coded Wire Tag Project Manual (pdf) or contact NMT for help.