Bumper year for Southern Right Whales in Algoa Bay
By Lloyd Edwards

1. News

This has been the best year for Southern Right viewing in the past 15 years. Raggy Charters have spotted at least 15 cow / calf pairs, that is 30 whales and another 15 single whales, probably males, which brings the total up to 45. They have also remained longer in the bay, around 3 months from the first until the last sighting on the 12th October.

This bumper year was not mirrored along our entire coastline. According to Dr. Els Vermeulen from the Marine Mammal Research Institute, 191 females with calves were spotted during the 42nd annual photo identification aerial survey. This survey is one of the longest uninterrupted datasets on any marine mammal on the planet. It was conducted between Natures Valley and Muizenberg. She said that the number of females should be at least around the 400 mark.

Data shows that these whales have drastically changed their feeding patterns over the last 20 years due to the availability of their food source. A shortage of food will also impact on their body condition and limit their breeding to every four to five years instead of every three years. When these whales were almost hunted to extinction it is natural that the breeding interval would shorten to increase numbers. Climate change must also surely play a role in their movement along our shores.

Although the survey is done in October, it may have been after the peak of the numbers here. It is always done during October as scientists are loath to change the parameters of the survey, obviously for very good scientific reasons. As an example, during another shorter survey between Hermanus and Witsand recently, researchers counted 209 females with calves.