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RESEARCH FAQ'S

RESEARCH

Do you have a research programme?

Yes. We study the movements and behaviour of great white sharks in and around False Bay. The information we learn is fed back into the safety programme to improve our methods and is also used to educate the public about shark safety and behaviour in and around Cape Town.

How do you study the sharks?

There are two main ways we study the sharks. One method is via dorsal fin identification. Each dorsal fin is unique to each white shark, so we take photos of any white sharks we come across so that we can compare them to other sharks we have documented in the past. Using this information we can determine how many sharks – and which individuals – come into False Bay year after year.

Another method of studying the sharks is by using acoustic tags. We have a network of acoustic receivers which are distributed in and around False Bay. We place acoustic tags on the white sharks and when the shark swims within about 500m of an acoustic receiver the time and date of that shark’s presence is logged on the receiver. Therefore we can determine what areas of the bay the sharks use and at what times of the year the sharks are using that area.

Are there a lot of great white sharks in False Bay?

False Bay has the second highest aggregation of white sharks in the world, after Gansbaai. To date roughly 440 different individuals have been identified coming into False Bay and the total population of white sharks which makes use of False Bay is roughly 700 individuals. This does not mean there are 700 individual white sharks in False Bay at any one time, as some sharks come regularly year after year, whereas other sharks have only been documented coming into the bay once over a ten year period. The maximum number of white sharks in False Bay at any one time is around 50 individuals.

What is the importance of mapping the shark activity over a long period?

White sharks can live up to 70 years of age and have different prey, use different habitats and have different habits over their lifetime, most notably from when they are born and feed primarily on fish and other sharks to when they start to consume marine mammals. Furthermore, there are long term environmental cycles which may influence distribution and habitat use. Therefore, it will only be through long term monitoring that we can better understand the drivers of occurrence and distribution.

Why are there less sharks/sightings/attacks on the Atlantic side?

There is limited research available on white sharks for the Atlantic seaboard side of the Cape Peninsula. While we know that they travel through the area, we are not aware of any aggregating areas e.g. like at Seal Island, False Bay or the inshore areas of the Bay.

However, the information available suggests that there are far fewer white sharks on the Atlantic side, spending far less time in that area. For example, data collected by the Shark Spotters at the Hoek, Noordhoek record few sightings per year (maximum number recorded per year was 4 – even though the spotter is on duty year-round).

Furthermore, out of 78 tagged white sharks, only 2 were recorded on the Atlantic seaboard side, and for a few minutes as it swam past the tracking receiver at Dunes, Noordhoek.

Lastly, our research and research from around the world increasingly shows a relationship between white shark presence and water temperature, thus we suspect this is the main reason that we have fewer white sharks, spending less time in the colder waters. Many reported “white shark” sightings, also turn out to be dolphins, sunfish or seals.

Why do some years have far fewer shark sightings than other years?

There is significant annual variation in the number of shark sightings and while we don’t yet fully understand the drivers of shark distribution it is likely due to a set of environmental variables e.g. water temperature, biological variables e.g. prey availability or even related to larger life-history cycles.

All Shark Spotters safety, research and education operations are currently suspended due to the COVID-19 pandemic and lockdown.
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