Cape Town - Marine biologists are cautiously optimistic after Great white sharks have been seen off the city’s beaches for the first time in more than four years.
Since 2017, the giant marine predators – growing up to 5m and weighing around two tons – seemed to have disappeared from the False Bay coast. Six years before, there had been 300 sightings.
In recent weeks, however, there has been a surge in great white activity in False Bay.
In a study earlier this year, Shark Spotters chief executive officer Sarah Waries, in an article published in The Conversation, said marine biologists were examining whether the decline in shark numbers in the Western Cape was indicative of a general decline in shark populations, or if the great whites had merely moved to another location.
In a shark advisory issued earlier this month Shark Spotters said four great white shark (Carcharodon carcharias to those who study them) had been spotted in False Bay, and cautioned swimmers and water users.
“There have been four confirmed reports of great white sharks in False Bay within the past week.
“The shark spotters at Muizenberg sighted a white shark on Monday, November 27 and on Wednesday, November 29.
“On Saturday, December 2, spear fishermen at Smitswinkel Bay reported seeing a white shark, and another white shark sighting was recorded off Roman Rock lighthouse by an experienced water user on the same day.
“At this stage, it is unclear whether these are sporadic, once-off sightings, or if this may signal the return of white sharks to False Bay in more numbers.
“In either event, we would like to remind water users to exercise caution whenever they enter the ocean, and to be aware that there may be more white shark activity in the bay than we have experienced in recent years.”
Shark spotters have not sighted great whites since 2017, after spotting over 300 off eight beaches in 2011.
Waries explained that water temperature, the phase of the moon, the time of year and food availability, as well as changes in the weather, all influenced the movements of great white sharks.
She further said most great white shark sightings came from Kwa-Zulu-Natal, with an average of 32 a year.
Shark Spotters, which essentially aims to keep sharks and people apart, was established in 2004, following a spate of shark attacks.
It has made over 3 000 shark sightings and brought about a reduction in the number of shark attacks.
Attempts to reach Waries for additional comment on the apparent increase in great white shark numbers in False Bay were not successful.
In a recent interview with Cape Talk radio, she said great whites had not been seen in False Bay since 2017.
“It is exciting that we have had four sightings in a week, [and we are] hoping it will signal the return of the sharks,” she said.
“But we just do not know; it might be that the conditions are good in False Bay and the sharks are just moving through.
“In 2015, we used to [make] 250 white shark sightings per year.
“Four in a week, we are not really back to the levels we were. Since 2017, we have seen a dramatic drop in white shark activity. Even in 2019 and 2020, we didn’t have any white shark sightings.
“It has gone from having 250 sightings a year to nothing, to now having sporadic sightings. Great whites play an important role in the ecosystem, and its function.
“Since the sharks left we have seen some small changes in the ecosystem in terms of increases in other sharks. So it will be interesting to see what happens when the white sharks do return.”