Port and Starboard, two orcas, have gained significant attention for their unusual behaviors and unique hunting strategies. Their actions have notably impacted marine ecosystems, particularly off the coast of South Africa. This article explores their identity, distinctive hunting methods, current status, and broader ecological implications.
Who Are Port and Starboard?
Port and Starboard are two adult male orcas, identifiable by their collapsed dorsal fins. Port’s fin bends left, Starboard’s bends right, a rare trait that gives them their nautical names. Researchers first sighted the duo near Lüderitz in 2009.
These orcas belong to a “flat-toothed” ecotype in South African waters. The exact reason for their collapsed dorsal fins is unknown, though theories include injury, age, or diet; it does not appear to affect their survival. They are often observed off Gansbaai, Port Elizabeth, Cape Town, and False Bay, maintaining a consistent presence in these coastal regions.
Their Notorious Behavior
Port and Starboard gained notoriety for their unusual and effective hunting strategy, particularly preying on large sharks, including great whites. Before their emergence, False Bay orcas primarily hunted marine mammals. However, since 2015, reports of sharks washing ashore with precisely removed livers directly linked these events to the duo.
Their technique involves targeting a shark’s pectoral fins to flip it upside down, inducing tonic immobility. Once incapacitated, the orcas surgically remove its liver, an organ rich in fats and nutrients, often leaving the rest of the carcass. This precision has been observed in attacks on various shark species, including great white, copper, and broadnose sevengill sharks. In February 2023, Port and Starboard killed at least seventeen sevengill sharks in a single day off Pearly Beach.
Current Status and Sightings
Recent observations confirm Port and Starboard’s continued presence in South African waters. In June 2023, Starboard was filmed attacking a great white shark alone in Mossel Bay. This marked the first recorded instance of a single orca preying on a great white, demonstrating an evolution in their hunting behavior, as orcas typically hunt cooperatively.
Tracking individual orcas is challenging due to their vast oceanic ranges and migratory patterns. However, researchers confirm their presence through distinctive features like collapsed dorsal fins and continued sightings. The latest observations, including the June 2023 event, indicate Port and Starboard remain active along the South African coast.
Ecological Impact and Significance
Port and Starboard’s predatory actions have led to shifts within South Africa’s marine ecosystem. Their consistent hunting of great white sharks resulted in a decline in shark sightings in areas like False Bay, where populations dwindled to near zero by 2020. This displacement of apex predators creates a “trophic cascade,” where changes at the top of the food chain ripple down to lower trophic levels.
With fewer great white sharks, populations of their prey, such as Cape fur seals, have increased. This has led to potential overgrazing of fish stocks and increased predation on vulnerable species like the African penguin. The absence of sharks can also impact ecosystem health; scientists noted a rise in rabies cases among seals in the Western Cape since June 2024, potentially linked to altered predator-prey dynamics. The study of Port and Starboard provides insights into predator-prey dynamics and the delicate balance of marine environments, showing how a few individuals can have profound consequences on an entire ecosystem.