Penguin Problems: Are human-induced food shortages driving population declines?

We all love penguins. Clumsy and awkward on land, stealthy and precise underwater- these charismatic creatures have captured our hearts ever since the release of March of the Penguins. Unfortunately, penguin populations across the globe (especially in South Africa and Antarctica) are facing hardship. Researchers have recently concluded that African penguin populations, as well as other seabird colonies, are plummeting due to overfishing. The issue stems mainly from the over-exploitation of sardines, the main food source of African penguins, Cape gannets, and Cape cormorants. As these seabirds struggle to find food, South Africa considers banning fishing activities near established colonies.

South African penguins have a preference for pelagic fish species, especially sardines

African penguins are endangered, making them a conservation priority and their decline over the years worrisome. Over three decades, South African penguins have collapsed by a staggering 73%-down from about 42,500 breeding pairs in 1991 to 10,400 by 2021. If this rate of decline is sustained, South Africa’s only endemic penguin species could be extinct in the wild within the next 15 years. The loss of sardines on account of overfishing and changes to air and water temperature are the main reasons behind these birds’ struggle for survival.

Before the proposal of a buffered no-take zone was made, penguin conservation efforts in South Africa were limited to site and rookery-specific mitigation measures. The implementation of the fishing ban would therefore represent the first wider ecosystem approach. Sardines are known to migrate great distances along the coastline, but if shoals move into the no-take areas, foraging penguin parents would have a unique hunting advantage. 

Purse seine fishing allows for a large amount of fish to be caught in a large surrounding net

Conservationists have now advised South Africa’s environment minister, Barbara Creecy, to halt purse-seine (this kind of practice involves scooping large shoals of fish with a large surrounding net) fishing within a 12-mile buffer encompassing the country’s six main island colonies which would offer 88% of South African penguins protection. Fishing small pelagic fish such as sardine and herring constitutes the livelihood of many local fishermen, however, the penguins depend on these fish species too, leading to animal-wildlife conflict and competition. 

African penguins (unlike other species) lay their eggs in burrows to protect them from the sun

As always, global warming also comes into play. Altered wind patterns and current upwellings lead fish to spawn in new and different areas, making them less accessible to penguins. In August 2020 alone, rangers from the South African Foundation for the Conservation of Coastal Birds saved almost a hundred starving chicks from Bird Island. The chicks were later taken to a rehabilitation facility for hand-rearing. The Algoa population from which the chicks came from, has seen a 33% decline in the past two years according to a 2021 census. If similar declines continue on a regional level, the African penguin could become ‘critically endangered’ according to the International Union for Conservation of Nature (IUCN). To make matters worse, African penguins have a preference for nesting in bird droppings, called guano, which used to accumulate 32 feet deep on the islands. Guano, otherwise termed ‘white gold’, is used to insulate the animals against the elements and provide safe nesting spaces. However, post the 1800s fertilizer boom, this white gold has all but disappeared. 

Further from global warming, penguins – though less so – face threats from shipping traffic, avian flu, oil spills, seal and shark predation, and increasing tourism. The last, though accountable for causing some disturbance, isn’t said to pose a major threat, with many penguins choosing to nest near gardens and boardwalks despite a variety of habitats to choose from. Laurent Waller, an ecologist with the Southern African Foundation for the Conservation of Wild Birds comments: “Such disturbances are minor, though. Even a recent freak incident this September, when bee stings killed 63 penguins, isn’t going to have an impact on the overall population level the way that other key threats are, particularly the reduced food availability, which is where most effort needs to be focused.”

Young African penguins at Boulder beach

However, as always, the issue divides opinion adding complexity to the discussion at hand. Expectedly, fishermen take a different stance on the problem with The South African Pelagic Fishing Industry Association (Sapfia) not in support of the ban. Although Sapfia recognises that South African penguin breeding populations are significantly reduced and that this phenomenon is concerning, they do not agree that commercial fishing is causal or that the consequent food shortages pose the single biggest threat to African penguin welfare. This follows an assessment by Prof Doug Butterworth (a leading international authority in fishery assessment) of the ban that he comments on by saying: “the 12-year island closure experiment – carried out at non-trivial-expense to the fishing industry – has led to results that show the impact, if any, on the penguins of stopping fishing around some penguin colonies will, at best, be to increase their annual growth rate only by about half-a-percent.” Further from this, the fishermen provide two main reasons for why their fishing activities are not responsible for the food shortages experienced by South African penguins. First, “the proportion of pelagic fish biomass harvested in South Africa is low compared to small pelagic fisheries elsewhere in the world”. And second, “the stock biomass is at 60-80% of its potential unfished level. These findings are based in part on credible biannual hydroacoustic surveys carried out by the research vessel, the Africana”.

African penguins surfing the ocean waves

In contrast, conservationists are of the unanimous opinion that fishing and the consequential competition for the same food source lies at the very heart of penguin decline. “The problem is that there’s a concentration of fishing efforts in areas that are targeted by penguins as well,” said McInnes from BirdLife SA. Following their independent research, the conservationists argue that Butterworth’s assessment is incomplete and inconclusive. “The results to date show two to four times more positive results than negative results for island closures. Given the current decline of the birds, the prudent response by the government, in adopting a precautionary approach, would be to protect those waters until there is unequivocal evidence to show the contrary.”

Tourists watching African penguins at popular Boulder beach

When considering the ban, it is also crucial to account for the financial impact the ban could have on the fishing industry. Mike Bergh, a scientific consultant to Sapfia, explained that if fishing was closed in a 20km radius around penguin colonies, the fishermen wouldn’t simply be able to fish elsewhere because anchovies are an “opportunity-based fishery”. Bergh also argues that “23.2% of anchovy catches and 30.1% of sardine catches would lie within the proposed closed area.” The pelagic fishery industry provides a cheap source of nutrition for many South Africans reliant on it for basic food security. Canned pilchards are an important part of the National School Nutrition Programme and “many of the companies have a contract with various school feeding schemes”, says Sapfia’s Mike Copeland. In contrast, conservation groups believe there would be major economic loss in South Africa if the penguins dependent on depleting stocks go extinct. In a study commissioned by the City of Cape Town in 2018, Dr Hugo van Zyl and James Kinghorn reported that in 2017, the African penguin colony in Simon’s Town alone brought in 930,000 visitors, creating 885 jobs and generating R311-million. 

So does this have to be an either-or scenario? Bergh says it doesn’t. “There is an opportunity for both fishing and the tourism sector to continue to generate revenue for the South African economy,” he says. However, until a consensus about the main reason for penguin decline is reached, this opportunity seems to be just that, with no concrete conservation action having the chance to commence. As is often the case, science proves ambiguous and indisputable conclusions hard to draw.

In the end, penguins may be black and white, but this issue is certainly not. 

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