Algoa Bay, in the Eastern Cape province of South Africa, is considered one of the most pristine marine environments in Africa. The waters around St. Croix Island, a 53-meter high quartzite outcrop four kilometers offshore, are especially nutrient-rich. For many species, St. Croix and a constellation of other islands in the bay provide a stopover on long migrations, a place to feed on anchovies and other prey.
For some species, however, St. Croix Island is a last stronghold — one that still can’t protect them from human exploitation.
As the catamaran-hybrid rounds the southeastern edge of the St. Croix, tour guide Purity Khosa points out a small band of African penguins, the only penguin species on the continent, huddled closely on the slick, mossy-green rocks right above the shoreline. Every now and then, one of the penguins lets out a deep bray that echoes off the cliffs.
In the nineteenth century, African penguins (Spheniscus demersus) numbered roughly 4 million across its southern Africa range. Since then, the flightless bird has declined more than 95 percent. The 8,000 individuals scattered around St. Croix constitute more than half of the total population and represent the largest remaining breeding colony of African penguins in the world. Even here, however, we can see evidence of why African penguin populations have declined so drastically.
Two empty concrete bungalows sit on the island’s western edge. The only built structures on the island, they’re known as the “guano huts,” and between 1945 and 1955, they served as lodgings for the laborers that stripped the island’s 12 hectare surface entirely of its “white gold.” The accumulated excrement of bats and seabirds, guano contains exceptionally high levels of phosphate, potassium, and nitrogen, which popularized its use as an organic fertilizer before the advent of chemical alternatives.
Penguins also use the island’s guano. While penguins are generally associated with cold climates, summer highs in Algoa Bay regularly reach the mid 30s Celsius, occasionally topping 40. To evade both the searing heat and predators, African penguins burrow underground nests, and with the rocky South African islands being mostly devoid of soil or significant plant growth, the accumulated guano cap presented the only viable alternative.
With the guano gone, penguins resorted to breeding in open-air nests, making them instantly vulnerable to predators such as kelp gulls and fur seals. Scientists on nearby Bird Island have observed gulls teaming up to snatch eggs from open-air brooding parents, who take turns to protect chicks and forage for food.
And it’s not only gannets and terns that find penguin eggs delicious. For a long time, so did humans. Reaching a peak in the first half of the twentieth century, penguin eggs were harvested on all of South Africa’s islands in astronomical numbers. Previously, the largest African penguin colony was 200 kilometers west of St. Croix, on Dassen Island near Plettenberg Bay, where, according to official records, more than 13 million penguin eggs were collected between 1900 and 1930. Similar harvesting on St. Croix brought the colony to a mere 1,000 individuals in 1937. While the practice known as “egging” was officially halted in 1969, by that time another threat to the penguins had already emerged.
Since the late 1940s, the harvesting of sardines and pilchards (also known as anchovies) has grown steadily in South Africa. These small pelagic fish are the most abundant in the oceans and constitute the most important catch for the South African commercial fishing industry, which harvests more than 500,000 tonnes of it per year. That same abundance also makes them the most important part of the African penguin diet, placing the penguin in direct competition with humans for food.
In a webinar for the South African National Parks Honorary Rangers society in August 2020, Lorien Pichegru, a marine biologist and adjunct professor at the Coastal and Marine Research Institute at Nelson Mandela University, discussed the competition for dwindling ocean resources. Pichegru referred to a 2016 report by the Food and Agriculture Organization of the United Nations that indicates that up to 30 percent of worldwide fish populations are overexploited, preventing the regeneration of stocks like those of small pelagic fish. She showed statistically how the decrease in African penguin numbers closely tracks the reduction in anchovy and sardine biomass over time. “Small pelagic fish are the cornerstones of our oceans,” she said in the webinar, “and their overfishing is the greatest threat currently faced by seabirds.”
Pichegru was closely involved with the establishment in 2008 of the Island Closure Task Team, a groundbreaking, multidisciplinary effort to increase prey availability for African penguins. Their main task was to quantify the effect of excluding purse-seine fishing (the method used to harvest small pelagic fish) from the waters around significant penguin colonies, including St. Croix Island. According to Pichegru, it had never before been shown conclusively that closing waters to fishing can help predators.
“What was really exciting,” says Pichegru, “was that within two years, we could see that no-take zones clearly benefit penguins.” The data indicated that within only three months of fishing closures around St. Croix Island penguins had completely changed their behavior and were now hunting for food much closer to home, drastically improving their chances for survival.
However, around the time of the establishment of the Task Team a new threat emerged with the completion of the Coega Harbour, a deepwater cargo terminal and the second commercial port in Algoa Bay. Once commercial operations commenced in 2009, shipping traffic in the Bay increased almost immediately, with Coega acting not only as a crucial container port but also as an important fuel stop for ships rounding the treacherous South African coast.
The terminal has been celebrated as a massive boost to the flailing economy of the country’s third most populous province, and one of its poorest. But conservation groups like the South African Foundation for the Conservation of Coastal Birds, or SANCCOB, are concerned with the shipping traffic’s impact on Algoa Bay wildlife. The terminal’s main eastern breakwater extends 2.9 kilometers into the bay, with shipping lanes passing directly through the main foraging area of African penguins around the Algoa Bay islands.
Oil spills are also a major concern. On July 6, 2019, for instance, a bunkering operation involving the MV Chrysanthi spilled between 200 and 400 liters of oil into the water close to the harbor entrance. SANCCOB staff caught, cleaned, and rehabilitated more than 100 adult and juvenile African penguins impacted by the spill, a process which, according to SANCCOB’s Preparedness and Response Manager Christian Triay, can take up to four weeks, and even longer for oiled chicks.
“Penguins are sentinels of the oceans,” says conservationist Lloyd Edwards, “and they are often the best indicator of the health of our marine environment. When the penguins are struggling, we know our oceans are sick.”
Edwards founded the Baywatch Project in 1992 to assist with marine research and law enforcement. A few years later, he founded Raggy Charters to conduct tours to the city’s islands in order to fund the work of that project. My China belongs to his fleet of educational vessels.
But Raggy Charters’ most important function, Edwards says, is creating awareness by conducting regular educational workshops at schools in local communities. “What we need is to educate, and you need to start with the kids, in the hope that maybe one day, they will have a better idea of what it takes to conserve our Bay,” he says.
Pichegru agrees that African penguins may yet recover, as long as the species can hold out at St. Croix. She refers again to the early 2000s, when her task team saw a temporary increase in numbers with an improvement in prey availability. “It really gives us a lot of hope,” she says, “because it shows that, when the conditions are right, the African penguins can come back.”
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