African penguins (Spheniscus demersus) are a unique seabird, recognized as the only penguin species that breeds on the African continent. These birds are easily identified by their distinctive black and white plumage, a unique stripe across their chest, and pink patches of skin located above their eyes. They are also known for their loud, braying call, which sounds similar to a donkey. Historically, millions of African penguins inhabited the coastal waters of South Africa and Namibia, but their population has experienced a drastic decline, estimated at around 97% over the past century. This severe reduction has led to their classification as critically endangered by the International Union for Conservation of Nature (IUCN). As of 2023, only approximately 9,900 breeding pairs remained in the wild.
Depleting Food Sources
African penguins primarily forage for small pelagic fish, with sardines and anchovies forming the bulk of their diet. These same fish species are heavily targeted by commercial fishing operations, creating direct competition for this vital food source. The extensive fishing pressure leads to a significant reduction in the availability of prey for penguins. Consequently, penguins are forced to travel greater distances from their colonies to find sufficient food. This increased foraging effort results in higher energy expenditure, which can negatively impact their breeding success and often leads to starvation, sometimes causing adult penguins to abandon their chicks. In an effort to mitigate this issue, South Africa has recently implemented fishing closures around six key penguin breeding colonies to protect these crucial food supplies.
Habitat Destruction and Degradation
The physical spaces where African penguins live and breed have been significantly impacted by human activities. Historically, the practice of guano harvesting removed deep layers of accumulated bird droppings, which served as vital nesting material and provided natural burrows for the penguins. Penguins traditionally nested within these guano burrows, which offered protection from extreme temperatures and predators. Their removal forced penguins to nest in the open, making their eggs and chicks vulnerable to environmental elements and various predators. Human encroachment and coastal development further disrupt breeding colonies, reducing suitable nesting sites. Marine pollution, particularly from oil spills, poses another substantial threat to their habitats. For instance, the MV Treasure oil spill in 2000 contaminated approximately 19,000 penguins, accounting for over 20% of the total population at that time. Oil exposure compromises a penguin’s natural insulation, causes skin irritation, and can be toxic if ingested during preening, impacting their long-term health and breeding success even after rehabilitation efforts.
Environmental Shifts
Broader environmental changes, particularly those linked to climate change, also affect African penguins. Rising ocean temperatures influence the distribution and abundance of their primary prey species. While sardine and anchovy populations naturally fluctuate, climate change exacerbates these shifts, making prey availability less predictable. Extreme weather events, such as prolonged heatwaves and unusual rainfall patterns, directly affect penguin breeding success. During heat stress, adult penguins may abandon their nests, leaving eggs and chicks exposed to hyperthermia or predation, while heavy rainfall and storm surges can destroy nests and flood burrows, leading to high mortality rates for eggs and young chicks.
Direct Threats and Mortality
African penguins face various direct threats that contribute to their mortality. Natural predators include Cape fur seals, sharks, and kelp gulls, which prey on both adult penguins and their chicks. Observations indicate an increase in Cape fur seal predation, impacting several penguin colonies. Introduced predators, such as domestic cats and dogs, along with mongooses and genets, also pose a threat near breeding colonies, particularly to nesting birds and their young. Disease outbreaks represent another significant cause of mortality within dense penguin colonies, such as an avian influenza (H5N8) outbreak in Namibia in 2019 that killed over 450 penguins on Halifax Island. Human activities directly harm penguins through incidents like entanglement in fishing gear, and isolated events like bee swarms or dog attacks also occur.