First record of South African Bryde’s whale feeding on plankton
On the 28 October 2024, Plettenberg Bay-based wildlife videographer Barry Skinstad filmed what is believed to be the first record of South African inshore Bryde’s whales (Balaenoptera edeni brydei) feeding on plankton. The inshore Bryde’s whale population is famous for lunge feeding (both surface and underwater) on small-pelagic fish such as sardine and anchovy and its movements along the coastline are understood to be governed by the migrations of these fish species. The ‘Sardine Run’ up the east coast of South Africa being an opportune natural phenomenon during which a host of predators (including Bryde’s whales and common dolphins) benefit from the dense shoals of prey.
At-sea observations, and the examination of stomach content remains from Bryde’s whales caught during the commercial whaling period in South Africa, revealed that whales from the inshore population feed almost exclusively on small-pelagic fish (Sardinops sagax, Engraulis capensis and Trachurus trachurus capensis), with shoaling squid (Lycoteuthis diadema) identified from one faecal sample (Best 1977; Best et al. 1984). No published records have documented whales from this population feeding on plankton, however Best et al. (1984) did observe a behaviour that could support possible at-surface plankton feeding; “…whales were seen lying on their sides at the surface with their throat grooves distended, possibly representing horizontal pursuit of prey at the surface.” However, the presence of plankton was not reported during those observations.
The image below is a screen grab from video footage taken in Plettenberg Bay, South Africa, whereby a Bryde’s whale lunges forward through a patch of plankton at the surface. The animal was observed doing this several times over a period of approximately half an hour and there was no evidence of fish in the area. To see the video, please follow this link to Barry’s facebook page.
Contributor: Gwenith Penry
