Recording fish tag info is important

ALBERT Einstein said: “Only two things are infinite, the universe and human stupidity – and I’m not sure about the former.”

When the environment is in question, man tends to ignore reality. In most cases I believe man really does not want to take on the responsibility!

A reader sent me an SMS about a cob he caught, tagged and released in the Swartkops River. It was clearly undersized at 480mm. The cob was recaptured about a month later and the recapture was recorded but the fish was kept. There is no way that the fish could have grown to legal size in 30 days!

The tag and release programme has been running for a few decades now and vital information has been gathered. Movements and growth rates have been recorded scientifically and as a result we now know things that were just speculation not so long ago.

It is vitally important that we record things correctly. In the absence of a tape measure, measure the fish with a piece of gut and record the tag number on your cellphone.

At home, the gut length can be accurately measured and that information forwarded. Please do not remove the tag if you intend releasing that fish, as a recapture and possible further information will be lost. Each tag used has a number that will never be reused.

You can contact me personally and I shall retrieve all the recorded information on the fish for you – where it was tagged, by whom and what the size was. The period of liberty will also be known from that report.

Most importantly, ensure the fish is properly revived before releasing it.

Fish with forked tails are measured from the snout to the fork. Fish like cob that have no fork are measured total length, from the snout to the middle of the fish’s tail. Non-edible fish are measured differently and we shall discuss that in a future column.

There are a few organisations that tag fish and this information is on each tag. The yellow tags are used nationally by The Oceanic Research Institute (ORI), where the tagging officer is Stuart Dunlop who can be contacted on (031) 3288222.

The blue tags and white tags are used by The South African Institute of Aquatic Biodiversity (SAIAB) and Dr Paul Cowley can be reached on 082TAGFISH.

Recently I witnessed two grunters that were tagged in the Sundays and the Gamtoos being re-caught in the Swartkops River. In both instances these fish were liberated for about 14 days only. It is not uncommon to have a garrick that was tagged in Durban harbour be re-caught along the Gamtoos surf and also in as many days!

Another example is a garrick caught in Algoa Bay by Ryan Kruger and re-caught three months later north of Durban by a team from Ushaka Oceanarium looking for specimens for their tank. This fish is now a resident at Ushaka. This shows that fish travel vast distances, presumably in search of different foods.

This week’s catch (pictured) shows a cob caught in the Sundays surf zone. Protruding from its anus is a length of trace gut.

This fish has been caught before and has a hook inside and the trace gut has passed through. Judging by the moss growing on the gut this fish, that appears in good health, has been swimming that way for some time.

This only proves that if the hook has been swallowed the fish will most probably still survive – so gone is that argument of why the undersized fish was kept!

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