Self locking tags

A. Self-locking ("cinch-up" and cable ties)

Hallprint's small self locking "cinch-up" loop tags (type SLS) are popular with some researchers and aquaculturalists where the following traits are important -

1. Very high long term tag retention rate
2. Minimal user skill required to achieve effective anchor in fish

Notwithstanding these positive features, SL tags are less popular for high volume tagging operations in which the primary objectives may be relatively short term movement patterns.

Hallprint's SL tag markers, like all of our tag markers, are made from a single moulded construction that can not fall apart under normal use.

The SL tag is a tag well worth considering for certain species in recreational or aquaculture fish tagging programs, particularly if user skill in tagging fish is not high.

A version of the self-locking tag which has gained in popularity is the standard approx. 100 mm x 2.5 mm and approx. 200 mm x 2.5 mm cable ties to which are attached our special moulded and outer sheath-protected markers. These are popular for use on macrophytic algae and are also being trialled as a "wrap-around" carapace and claw tag on crabs and as a band tag on marine turtles.

B. Wire-on tags

Hallprint's wire-on tags (Type WOT) are a highly versatile loop tag which has been popular on use with some shellfish, crustacea and finfish. Although with shellfish it has been largely superseded by the type FPN glue-on shellfish tags, a variation of it had has recently been used successfully as a wrap-around carapace tag for crabs and as an opercular tag for flatfish. The tag consists of the highest possible grade of stainless steel which lies inside a solid core of inert or "non-migratory" polyethylene with an outer protective sheath that ensures that our superior print legibility lasts forever.

Available in both standard and large diameter wire, we can also vary the length of the tag, the coloured sleeve and the protective sheath to suit your specific needs.

Wire-on tags are most suited to tagging operations where very high rates of tag application are not necessary and morphological features of the fish make more traditional fish tagging techniques less suitable.

Application instructions for self-locking "cinch-up" loop tags (A. above)

Ensure that tags are not exposed to direct sunlight and above ambient heat levels for prolonged periods when in storage.

Loop tags are applied with a special hollow needle applicator that has a solid point. The tag is loaded into the needle with the “female” part of the self-locking mechanism trailing from the hollow end. The needle is then passed through the muscle a centimetre or so anterior to the leading edge of the dorsal fin and a 2/3 scales ventral to the dorsal edge.

The needle is then pushed right through the fish. The female part of the locking mechanism should remain outside of the fish. The needle is then removed leaving the unlocked tag as a “spear” through the fish. The male end is then locked into the female end and pulled through until the desired loop diameter is achieved. The male end is then trimmed to the join and then the join is rotated until it is inside the muscle of the fish and only coloured marker is visible outside the fish.

The fish is now tagged and should be released asap. Remember to record both length, species and tag number before the fish is released!