Hallprint's range of plastic tipped dart tags (see below) are designed to provide a diversity of high quality options for researchers embarking on a finfish tagging program. As with the T-bar anchor tags, dart tags are normally applied in such a way that the barb locks behind about the second or third leading dorsal fin ray. In elasmobranchs the barb is lodged in a cartilagenous section of the fish, usually in the body of the fish adjacent to the dorsal fin in sharks or in the "wings" of rays and skates.
The correct tagging technique for the dorsal application of plastic tipped dart tags to finfish is shown here (click on picture to see video) -
From the top PDA, PDS, PDL, PDW, PDX tags
The smallest dart tag, the PDX, is applied with an approx. 2.4 mm outside diameter applicator needle. It is suited to finfish species between about 20 cm and 30 cm. These tags are popular for small fish likely to undergo fast growth rates such as juvenile tuna.
The small dart tag range (PDS, PDL and PDW) is applied with an approx. 3.3 mm outside diameter applicator needle. This range is suited to fish across a wide range of sizes, with the PDS and PDW tag suitable for fish from about 35 cm up to about 55 cm and the increasingly popular "dogleg barb" PDL tag which is suited for fish up to about 80 cm. These tags are very popular with recreational fish tagging programs for a wide variety of species due to the ease of use and lower unit cost of applicators compared to T-bar tags.
Large dart tags (PDA) are applied with an approx. 4.0 mm outside diameter needle and are proven performers with finfish and sharks from about 60 cm including tuna, barramundi, snoek, tarpon and spanish (king) mackerel to name a few.
Hallprint is continually working closely with researchers to further improve the range of options available in terms of dart tag design. A recent addition to the range is a new extra small dart tag with an elongated "dogleg barb" (type PDXL below) which can be used with a 2.4 mm outside diameter needle and that should suit finfish to around 45 cm or more.
New extra small long barb PDXL tag
Detailed user instructions will be provided with each tag order. The following photos show the application procedure.
PDA tag being applied to a red grouper (photo courtesy of Nick Parnell, Mote Lab, Florida)
Schematic diagram showing correct placing and location of dart tags with tag head anchored between dorsal pterygiophores
Plastic tipped dart tag applicator needles
Hallprint's plastic tipped dart tag applicators are manufactured from the highest quality industrial stainless steel available. Three differing diameters are available. The smallest diameter applicator is for use on the "extra small" sized dart tags only (type PDX). The next largest diameter applicator is designed for the three "small" diameter dart tags ie the PDS, PDL and PDW. The largest diameter applicator is designed for the large plastic tipped dart tags (PDA) only.
These applicators can either be used alone or attached to a dowell handle. A "chuck" style handle for interchangeable screwdrivers available from most hardware stores is handy for applying pre-loaded applicators on high volume tagging operations.