Tagging is an important technique fishery biologists use to study individual aquatic animals (e.g. fish) or populations. They will generally tag or mark aquatic animals to obtain important information necessary for research or management. By reporting tagged or marked fish (i.e. a recapture), you can assist in:

1- Stock identification -determining whether stocks or sub-populations are connected and are being utilized for sport or commercial fisheries

2- Migrations - figuring out the path and distance of migration, rate of movement, and homing tendencies of a particular species

3- Behaviour - identifying factors that limit abundance such as habitat selection and intra- and inter-species interactions

4- Age - validating the age of fish, particularly for aging methods (e.g. counting growth rings on a scale) and determining growth rates

5- Mortality rates - following the effects of natural and fishing mortality on a fish population




The ORI-CFTP is strictly a marine based project. This means we do not tag freshwater fish species, although we do tag fish in estuarine environments. A large variety of species are eligible to be tagged as part of the project, although fish less than 30 cm (0.5 kg) are not tagged. Please download the latest priority species list. There are many different types of tags used on different fish species (e.g. satellite tags, acoustic tags, archival tags, etc.). The ORI-CFTP use external dart tags, which consist of a monofilament vinyl streamer attached to a plastic barb, much like a miniature version of a spear from a speargun. Each tag is inscribed with a unique alpha-numeric code (e.g. D123456) and contact details (i.e. email address, cell phone number and postal address).

Tags are generally inserted with a sharp, hollow, stainless steel applicator, into the dorsal musculature of a fish or shark, although this may differ in certain fish species (e.g. rays). There are three types of tags used on the ORI-CFTP. These include A-tag (sharks and rays and large bony fish >60cm), D-tags (smaller bony fish between 30 and 60 cm in length) and M-tags (billfish and large tuna >25 kg). Tags are generally inserted with a sharp, hollow, stainless steel applicator, into the dorsal musculature of a fish or shark, although this may differ in certain fish species (e.g. rays). Upon initial tagging (and subsequent recapture of a tagged fish) anglers record the following information: tag number, fish species, length (fork/total/precaudal/disk width), exact locality and date. The use of external tags by the ORI-CFTP is particularly favourable as it is relatively cheap compared to other tagging methods, relatively little training is required to insert tags, no software is required to download information from each tag, and the tagging equipment is very basic. This allows a relatively large number of fish to be tagged fairly economically and allows citizens who are not trained scientists to be involved, similar in some respects to the South African Bird Ringing Unit. However, considerable attention has been focused on ensuring that the best available tag and tagging equipment is used and that our taggers are shown how to handle and tag fish correctly, in order to minimize post-release mortality.


If you are interested in making a significant contribution to conservation and management of our marine linefish species, live near the coast, fish often and know your different fish species then please complete an application form to apply to become a member of the ORI-CFTP. An email will be sent to you once your application has been submitted. You will be notified if your application is successful and will be required to purchase a starter kit with everything you need, including instruction manual, tape measure and tagging equipment (dart tags and applicator).


If you are interested in learning how to handle and tag fish correctly please consult the following material. If you follow these guides you will be on your way to successful tag and release.


A tag recapture is a fish that has been caught with a tag in place. One of the major problems faced by the ORI-CFTP is the low reporting rate for the recapture of tagged fish. An in depth study of 1200 shore and boat anglers from KwaZulu-Natal in 2009 revealed that 42% of anglers that had caught a tagged fish had simply released the fish without recording the tag number or had simply not bothered to report it. Obviously this low reporting rate is not ideal for the ORI-CFTP. Consequently we have developed a number of initiatives to help increase this reporting rate. These include a dedicated email address (oritag@ori.org.za), cell phone number (+27 79 529 0711) and an online submission form.

Remember that a tagged fish does not “belong” to anyone and should it be recaptured, the angler who caught it is fully entitled to keep it, so long as it complies with the relevant fishery regulations. However, it is crucially important that when an angler catches a tagged fish he/she reports the relevant information promptly and correctly to ORI. Valuable information is often lost with the delayed reporting of the recapture as well as the incorrect reading of a tag number or poor measurement of the fish length.

Tag number - this is the number (in most cases 6 digits) on the tag as well as the tag type (a letter before the tag number) - e.g. D132526 or A142576. It is not advisable to remove the tag if you are going to release the fish again; rather carefully read the tag number (ask someone to verify this number if possible), measure the fish, write down this information and then re-release the fish. If it is not possible to read the tag number then cut the back number off the tag just behind the email address. Make sure that you have the tag type (A, B, D, or M) and the numbers (up to 6 digits) on the section of tag you have cut off. Remember, if you don’t have a pen or pencil, you can record the details on your cell phone (or take a photo of it).

Species - this is the species/type of fish you have recaptured. If you are not sure what species it is, write down what you think it is followed by a “?” and give us a brief description or if possible take a photograph. Some species have many common names which can be confusing. Please use the accepted common name in full (e.g. spotted grunter, not just grunter as there are a number of different grunter species).

Correct length measurement - It is essential that we receive correct measurements from you. If you do not have a tape measure use a piece of nylon or string to measure the fish with, marking it with a knot at the correct length. When measuring a fish do not lie the tape measure/string over the body but rather hold it under the fish or in as straight a line as possible. Indicate on the return what measurement type was taken (i.e. fork length, total length, precaudal length or disk width).

For accuracy we require our tagging members to measure fork length if the fish has a forked tail (e.g. kingfish), total length if it has a straight or rounded tail (e.g. kob, rockcod), precaudal length if it is a shark with a precaudal notch (e.g. dusky shark), or disk width (wing span) if it is a ray. Total length should be measured for spotted-gulley sharks, hound sharks, cat sharks and sand sharks. If you are uncertain about which length type to measure, then simply measure more than one (e.g. fork length and total length or precaudal length and total length). Remember, length measurements for minimum legal size limits are always total length.

Exact locality - this is the exact area where you caught your tagged fish. This needs to be quite specific and always state the province and or major river/town in the vicinity to ensure that we know exactly where you were fishing. Our coastline extends 3000 km and many of the fishing spots have the same name or many different names. A geographic coordinate (i.e. GPS point) is not necessary but if you have recorded them please provide one.

Date - this is the date of recapture. Please use the standard format YYYY/MM/DD.

Whether the fish was kept or released - this is important as if the fish was re-released was the tag left in the fish or removed? A fish that has a tag in it should never be retagged unless the original tag was removed.

Angler name and contact details - Supply us with your name, email address and phone number in case more information is needed. We send out an exciting, detailed report on recaptured fish to the angler who caught it and sent us the information. Remember that the more accurate your information is the better the report will be.


Fish is tagged and released

Fish spends time at liberty

Tagged fish is recaptured

Recapture details recorded by angler
After details are recorded, fish is either released or kept

Recapture details sent to ORI

Recapture report generated by ORI
Original tagger and angler who recaptured the fish are notified by email and provided with movement and growth details.