In October last year the KwaZulu-Natal Sharks Board (KZNSB) reported on the recapture of a tagged ragged-tooth shark (Carcharias taurus) – which are commonly known as raggies – that had been at liberty for 20.7 years. This is the longest recorded time at liberty the species in Southern Africa – possibly in the world.
Pictures by Geremy Cliff
Since then, two more exceptional recaptures have been reported. A ragged-tooth shark tagged near Southbroom, on the KZN South Coast, after being released from the shark nets in 1990, was recaptured by an angler at the mouth of the Great Fish River in January this year, making this the second longest time at liberty (20.5 years).
Another shark, tagged by KZNSB snorkel divers in 1995 at Leven Point in the St Lucia Marine Protected Area, was recaptured at Richards Bay in February after 15.1 years at liberty. These three sharks replace the previous record holders of 13, 12.9 and 12.8 years.
Click here for Record Raggie Recapture
The Sharks Board has been tagging sharks and rays since 1976 and to date has tagged more than 6 000 animals. It has been an active member of the South African National Tagging Programme since its inception in 1984. This programme – administered by Durban’s Oceanographic Research Institute (ORI) – is one of the longest operating tagging programmes in the world.
Since the late 1980s the KZNSB has tagged all shark species found alive in the protective gear but initially the only tagging done by the organisation was of free-swimming ragged-tooth sharks. Most of this type of tagging, which is ongoing, has taken place near Leven Point. A pole sling is used by snorkel divers to insert a dart tag with a stainless steel head and plastic streamer.
These remarkable recaptures highlight the value of long-term tagging projects. such as that run by ORI. – Sabine Wintner, Senior Scientist
Info courtesy the KZN Sharks Board
Email; wintner@shark.co.za; more on the web