“There’s only one species that’s native to Africa. And it’s disappearing fast.”

Some of my favorite research to read on penguins are case studies because they provide a glimpse of how weird penguin behavior can get. Occasionally, a few penguins in a population might display a behavior they’re not supposed to do. In this case, a few African penguins began stealing one another’s nests, also known as nest usurpation, in response to extreme weather changes [1]. 

When African penguins lay their eggs in surface nests, they become susceptible to overheating [1]. In March 2017, extremely high temperatures caused some penguins in surface nests to lose their offspring, while ones in shady areas generally fared better [1].  

By April, some penguins were successfully raising chicks in a nest while others were searching for territory to try to hatch replacement chicks [1]. Breeding out of time with one another caused territory-seeking penguins to be more aggressive than chick-raising penguins [1]. 

In their study, researchers Traisnel and Pichegru documented three instances of nest usurpation in the Bird Island penguin colony, which was previously undocumented in African penguins [1]. In the first instance, a bold chick-raising penguin defended her nest from an intruder until her mate came and both adults fended off the aggressive penguin [1]. 

In the second occurrence, an aggressor chased a shy penguin off her nest, pecking her larger chick to death [1]. The smaller chick escaped the attack by running into a nearby nest [1]. It was sent to be hand-reared at a facility specializing in African penguin rehabilitation [1]. 

Finally, a penguin and its two chicks escaped an attack by abandoning their nest, and after six weeks, the adult was seen with only one chick in tow [1]. The aggressor raised two chicks in the stolen nest [1]. 

As a result, climate change is indirectly linked to negative interactions among penguins, like the death of healthy chicks [1]. Traisnel and Pichegru suggest providing ample artificial nests for penguins to reduce this unwanted behavior [1]. 

I hope you have enjoyed this blog, as this is my final post now that I’ve completed my requirements for class. Thanks for reading! 

References:

1. Traisnel, G. and Pichegru, L. 2018. Possible drivers of nest usurpation in African Penguins Spheniscus demersus. Marine Ornithology 46: 85–88.

Hey readers! I know that reading too much about threats to an endangered species can sometimes make you feel helpless, so I thought I’d write a special lighthearted blog. Throwback Thursday goes back in time to examine ecological and behavioral research that remains relevant today. 

In 1973 through 1976, researchers Eggleton and Siegfried traveled to islands off the South African coast to observe African penguins in their natural habitat. They composed an ethogram, or description of behaviors, for this species [1]. Their 1979 paper provided the foundation for other behavioral research on African penguins, including mine. Here’s a list of some of the more interesting behaviors the researchers described. 

1. Ecstatic 

The ecstatic behavior earned African penguins another name – the Jackass penguin. In this display, the penguin raises its head toward the sky with its flippers extended horizontally at its sides and beak open [1]. Then, the penguin brays [1], exactly like the hee-hawing of a donkey. This behavior most commonly occurs in male penguins as an advertisement to females that they have a territory and are looking for a girlfriend [1]. 

2. Vibratory Head Shake (VHS) 

In this behavior, a penguin rapidly swings its head from side to side, sometimes through a full 180 degrees, while sitting or crouching [1].  Bonded African penguins perform VHS on their nests, either as a greeting to their mate or to appease aggression so that two penguins can inhabit the same small space peacefully [1]. A lone penguin may occasionally perform this display on its nest, suggesting territoriality [1]. 

3. Allopreening

African penguins allopreen when one penguin straightens the feathers around another penguin’s head and neck by nibbling with its beak [1].  Sometimes, both penguins will allopreen one another simultaneously [1]. This behavior occurs commonly between bonded birds, as well as parents and chicks [1], and it’s criminally cute. 

In addition to these weird and wonderful displays, African penguins have six different aggressive behaviors and too many comfort behaviors to list here. But it’s thanks to Eggleton and Siegfried that I know how to define, describe, and rationalize African penguin behaviors. It’s thanks to them that I can do my research without the extra headache of trying to figure out what the penguin is doing. And thanks to them, I appreciate the diversity that the African penguin brings to this world. 

References:

1. Eggleton P., and Siegfried W.R. 1979. Displays of the Jackass Penguin. Ostrich 50: 139-167.

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I’m always interested to see how penguins worldwide are faring, especially since it can be hard to determine which penguin species are most at risk. Most of the time, I live in an African penguin bubble, only researching similar species when I can’t find anything relevant to my own research.  

However, I recently stumbled across a rare gem – the International Union for Conservation Species Survival Commission (IUCN SSC) created a Penguin Specialist Group (PSG) to assess species most at risk and identify conservation needs. The paper they published considers all 18 species of penguins, making it unique. 

The experts used a systematic approach to identify the biggest threats to penguins, then determined the most vulnerable penguins based on unanimous votes [1]. The PSG declared that three species are “international priorities” that require immediate conservation action: the African, Yellow-eyed, and Galapagos penguin (above) [1]. 

For African penguins, the PSG recommended implementing fishery management throughout the penguins’ range, as it currently covers some of their breeding grounds but not the range of wandering juveniles [1]. The PSG suggested the management of fisheries, removal of invasive predators, and creation of predator-free breeding sites to aid the Galapagos penguin [1]. Their most important advice for Yellow-eyed penguins is to start tourism planning and using marine resources sustainably [1]. 

For all penguins, the PSG hopes to promote seasonal fishery closures and overall management. They also highlight the need for more long-term research, especially in the non-breeding season, when penguin mortality rates are highest [1]. 

Finally, the PSG emphasizes the importance of researchers communicating with others outside the scientific community [1]. Many scientists take their data and publish a paper, but this approach alone isn’t enough to bring about change. Scientists must team up with nongovernmental organizations, legislators, stakeholders, and managers to turn their conservation ideas into action. The future of penguins depends on it. 

References:

1. Boersma, P., Borboroglu, P.G., Gownaris, N., Bost, C., Chiaradia, A., Ellis, S., Schneider, T., Seddon, P., Simeone, A., Trathan, P., Waller, L. and Wienecke, B. (2020), Applying science to pressing conservation needs for penguins. Conservation Biology, 34: 103-112. doi:10.1111/cobi.13378. 

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Why am I writing about Magellanic penguins from South America now instead of African penguins? For one thing, Magellanic penguins’ conservation status is near threatened, so we need to better understand them if we want to prevent further population declines. More importantly, African and Magellanic penguins are extremely close relatives, so research findings in one species may be applicable to the other. 

In a recent study, researchers monitored a colony of Magellanic penguins at Punta Tombo, Argentina, by banding approximately 44,000 chicks over the course of 33 years [1]. The researchers determined the sex of 57% of the penguins they banded and tracked the individuals throughout the years [1].  

During the non-breeding season, when Magellanic penguin mortality is at its highest, the researchers discovered that females have a lower survival rate than males, whose survival rate is 33.3% greater than that of females [1].  

Moreover, female Magellanic penguins suffer their highest mortality rate as juveniles, rather than adults, possibly because they are less efficient at foraging [1].  

The researchers determined that this sex bias in survival is responsible for the Punta Tambo population decline from 1990 to 2009, which is roughly 40% (determined starting in 1987, documented in scientific literature in 1990) [1].  

The authors hope that management of fisheries and habitat space could mitigate the loss of females and thus, further decline of Magellanic species [1]. They also stress the importance of determining sex bias in survival rates for other seabird colonies to accurately monitor their populations [1]. 

Because African penguins are genetically similar to Magellanic penguins, I think that an assessment of sex-biased survival in African penguins could help to examine additional causes of population decline and introduce new tactics to preserve this endangered species. Studies on Magellanic penguins could save their cousins from across the Atlantic.

References:

1. Gownaris N. J., and P. D. Boersma. 2019. Sex-biased survival contributes to population decline in a long-lived seabird, the Magellanic penguin. Ecological Applications 29(1): e01826. 10.1002/eap.1826.

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Many of the blogs that I have posted before discussed the human influence on the decline of the African penguin population. So, imagine my surprise when I came across a study that examines the influence of natural predators on mainland African penguin colonies. For once, humans aren’t the villain in this study. 

Instead, the bad guys are land-based predators of African penguins – namely leopards, caracals, domestic dogs, and mongooses. While they are natural predators of the African penguin, they can sometimes go on killing sprees [1] in which they kill many penguins in a short period of time, eating almost nothing.  

While many predators exhibit this “surplus killing” behavior, it’s particularly problematic when their prey is an endangered species. As a result, it’s important to successfully and quickly identify the culprit of killing sprees on African penguins.

In this study, researchers obtained 52 penguin carcasses killed by caracals, 27 by leopards, 10 by domestic dogs, and four by mongooses [1].  Experienced veterinarians performed autopsies on the penguins, examining and comparing lesions and bite marks to differentiate between predators [1]. 

In the African penguin carcass, both leopards and caracals bite the neck, although leopards aim for the lower neck and exert a greater force through their larger bite [1]. However, domestic dogs use blunt-force trauma to kill penguins rather than biting, causing lung and kidney damage by crushing the chest, thereby resulting in a “messy” kill [1]. Finally, mongooses ate the neck muscles of the penguins, resulting in decapitation or near-decapitation, and opened the skulls of chicks [1]. 

I think the value of this study lies in its report on attacks specific to the African penguin. Because the researchers documented attacks by each predator on penguins exclusively, veterinarians can better identify the type of animal that killed the penguins. As a result, authorities will hopefully be able to manage predator species and react more quickly when killing sprees occur to reduce the number of African penguins involved.

References: 

1. Ralph ET Vanstreels, Nola J Parsons, Cuan McGeorge, Renata Hurtado, Katrin Ludynia, Lauren Waller, Monique Ruthenberg, Arne Purves, Lorien Pichegru, Pierre A Pistorius (2019). Identification of land predators of African Penguins Spheniscus demersus through post-mortem examination, Ostrich, 90:4, 359-372. 

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In my blog post last week, I said that the population of African penguins in Namibia is relatively stable compared to those in South Africa. However, that doesn’t mean that the Namibia population is immune from environmental stressors, like illness. 

From mid-December 2018 to mid-February 2019, a devastating disease plagued the African penguin population on Halifax Island, Namibia. Although no other bird species on the island contracted the disease, over 350 African penguins died, most of which were breeding [1]. 

In order to discover what illness had afflicted the penguins, researchers took samples using swabs from three penguins that showed the following signs of illness [1]: 

• Emaciation 
• Lethargy or comatose behavior 
• Twitching 
• Uncoordinated movements 
• Torticollis – a condition of the neck muscles that causes the head to droop 
• Corneal opacity – scarring on the cornea that causes the eye to appear white 

The researchers also performed an autopsy on five penguin carcasses. Although the penguins appeared fine on the outside, they discovered that the penguins had suffered hemorrhages and internal bleeding, especially along the gut [1]. 

From the swab samples, as well as a sample cut from the liver of a deceased penguin, the researchers sequenced the virus’s genome [1]. From this data, they found that the virus was H5N8 avian flu, a very severe strain [1]. 

While the researchers identified the virus that caused the outbreak, they cannot trace its origin [1]. It most likely reached Halifax Island through the movements of wild birds [1]. 

I think that one of the main takeaways from this study is that although the penguin population in Namibia is holding its own, it doesn’t take much to harm it. As a result, even the African penguin populations that we currently deem stable are still vulnerable. 

References:

1. Umberto Molini, Gottlieb Aikukutu, Jean-Paul Roux, Jessica Kemper, Charles Ntahonshikira, Giuseppe Marruchella, Siegfried Khaiseb, Giovanni Cattoli, and William G. Dundon (2020) Avian Influenza H5N8 Outbreak in African Penguins (Spheniscus demersus), Namibia, 2019. Journal of Wildlife Diseases: January 2020, Vol. 56, No. 1, pp. 214-218.

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As I’ve said in previous posts, there are only 20,850 breeding pairs of African penguins in the wild as of one month ago. That’s it. Three and a half years ago, when I first started my undergraduate research, that number was approximately 30,000.

Where am I getting these numbers from? The latter comes from the South African National Biodiversity Institute (SANBI), whose page on African penguins was last updated in May 2018. The former comes from a recent paper published in January 2020 in which researchers determined the extinction risk of the global African penguin population according to International Union for Conservation of Nature (IUCN) criteria [1]. They also assessed rates of decline by countries as a whole and individual penguin colonies within each country [1]. 

The researchers discovered that the penguin populations in South Africa are steadily declining by 5.1% per year, while the population in Namibia is more stable, only decreasing by 0.1% per year [1]. Within South Africa, the penguin colonies in the West Cape have lost 10% of the population per year over 20 years [1]. This large loss reflects a decrease in African penguins’ prey availability in the west, which is at the center of their breeding grounds [1]. The drastic decline in West Cape penguins means that most of the penguin population resides on the Eastern Cape of South Africa, a common route for shipping vessels [1]. 

To me, this study is both devastating and hopeful at the same time. It clearly shows how quickly the African penguin is disappearing, yet also pinpoints key areas where changes in conservation management are needed. 

If you want to help the African penguin, you can symbolically adopt a penguin at an Association of Zoos and Aquariums (AZA) accredited zoo.

References:

1. Sherley RB, Crawford RJM, de Blocq AD, Dyer BM, Geldenhuys D, Hagen C, Kemper J, Makhado AB, Pichegru L, Upfold L, et al. 2020. The conservation status and population decline of the African penguin deconstructed in space and time. bioRxiv, 1-20. Accessed from: Google Scholar.
2. Seiphetlho, N. L. African penguin. South African National Biodiversity Institute. 2014. Available from: https://www.sanbi.org/animal-of-the-week/african-penguin/

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Not all penguins in a relationship stay true to one another. There’s a lot of drama: I’ve seen a pair of “gay” penguins split after years of companionship, a divorce after the parents’ chicks grew up, and the occasional guilty penguin that allopreens someone other than its partner. But I’ve never seen anything as scandalous as what a genetic analysis on African penguins at an Italian zoo uncovered.

In this zoo, African penguins are housed in the same exhibit as their close relatives, the Magellanic and Humboldt penguins, both of which are native to South America. 

WHICH RELATIVE IS WHICH?

Researchers decided to do a genetic analysis on the African penguins, exclusively, in order to see if genetic diversity is maintained in the colony and if studbook records were correct.  

A studbook is a pedigree or family tree for a specific animal; just as we may record our family’s ancestors and their relationships to one another, zookeepers do the same for penguins. 

Perhaps the most outrageous part of the scandal is that researchers identified four of the penguins as hybrids with Humboldt penguins, although all of them looked like African ones. Some hybrids are partially fertile and may have chicks, like Umbo, a penguin at the Italian zoo that had two sons and a grandson. Experts still debate over whether the mixing of African and Humboldt penguins will be beneficial or threatening for the future of African penguin populations. 

While the advent of hybridization doesn’t affect the penguins at my zoo since only one species is housed there, it does concern larger zoos and aquariums that may have multiple species in one exhibit.

I think that one of the most important points from this research is that zoological studbooks may not be accurate. As a result, it’s going to be extremely difficult for conservationists to maintain the African penguin pedigree. 

Morgan Blickley, Undergraduate Penguin Researcher

But that’s not all. Since penguins all look the same, those of us who study them have to figure out their sex based on their appearance and behavior. So our assessment may boil down to this simple fact: males usually have bigger beaks. In one case, the researchers at the Italian zoo surprised zookeepers by identifying a bonded pair of penguins as female-female, not male-female as they had originally thought. These “gay” penguins also hatched an egg, which one of them had laid after mating with a male. 

Finally, the researchers discovered that five penguins had hatched out of wedlock, so to speak – these individuals were the result of infidelity – and zookeepers didn’t know about two of them. Thus, this study showcases a need to combine genetic and studbook data to ensure the best conservation efforts for the African penguin.

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This blog post, except first paragraph, images, penguin physical descriptions, and pull-quotes, is summarized from the following study:

Modesto P, Biolatti C, Favaro L, Colussi S, Peletto S, Piga S, Riina MV, Pessani D, Trincas E, Isaja V, Acutis PL. 2018. Molecular Genetics Unveiled Unknown Family Relationships and Hybrids in an Ex-Situ Colony of African Penguins (Spheniscus demersus). Journal of Heredity. 109(6): 653–662. Accessed from: Google Scholar.

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