Note: Consider Nature contains some strong language and adult themes which may be inappropriate for younger readers. Reader discretion is advised.
It’s tough being small. Many people and conservation organizations have devoted most of their attention to preserving large, traditionally-charismatic animals such as tigers, elephants, and pandas—easily-recognizable species which captivate our imaginations. While all of these species certainly deserve conservation attention, the little guys often get overlooked when it comes to allocating resources, even if they play important roles in maintaining their ecosystems.
I want to tell you about one of those little guys. This tiny tortoise, no larger than a baseball, has a huge ecological impact in one of the most diverse and species-rich ecosystems on Earth. Yet, this species’ importance to its home has only recently been recognized, and human land development has pushed it to the brink of extinction. This one's for all the short kings out there. Consider: the Karoo Padloper, Chersobius boulengeri.
Reaching a maximum length of 110 millimeters (4.3 inches), the Karoo padloper (also known as the Karoo dwarf tortoise, but that name isn’t nearly as hobbit-esque) is one of the smallest tortoise species in the world. In addition to providing defense, the shells of karoo padlopers act as excellent camouflage, with colors and patterns designed to mimic the rocks and pebbles strewn about their craggy habitats (not a very ambitious choice of disguise—how hard is it to pretend to be a rock?). The tortoise’s front limbs are also covered in thick scales and come together to cover their heads when they retract into their shells, providing an additional layer of defense (padloper used Defense Curl!).
These White Castle slider-sized fellows live in the Karoo, a semi-arid region in Africa that rivals the Amazon Rainforest in terms of species richness. Covering much of Namibia and South Africa, the Karoo contains more than 6,000 species of plants, 40% of which are found nowhere else in the world and 900 of which are at risk of extinction. For every square kilometer (~⅓ square mile) of land in the Succulent Karoo, the ecologically-richest of the Karoo’s four regions, over 70 species can be found living in close proximity to one another. Hot, dry, and filled with a variety of shrubs and bushes to munch on, the Karoo is prime tortoise territory, and it’s no surprise that a quarter of the world’s tortoise species live in South Africa alone.
Featherweight Fighters
As one could imagine, being a snack-sized tortoise puts you on the dinner menu for a lot of predators. To avoid getting gobbled up, Karoo padlopers spend 80 to 90% of their time hiding under sills created by rock formations, where they blend in perfectly with their surroundings. These tortoises spend so much time hiding that they often only move a total of 28 meters (91 feet) each day. Corvids, such as the white-necked raven and pied crow, are the most enthusiastic Karoo padloper predators. While most predators may feel like getting a Karoo padloper out of its shell isn’t worth the effort (much the way I feel about pistachios), crows and ravens can bypass the tortoise’s defenses with their impressive problem-solving skills. Corvids will carry Karoo padlopers high into the sky and drop them onto the rocks below, cracking their shells open with the power of gravity (this is incidentally how Dwayne “the Rock'' Johnson lost Hell in a Cell 2000). The victorious birds can then pick the bits of turtle meat out of the shrapnel.
In addition to watching the skies for death from above, Karoo padlopers have something else to look out for: each other. The tortoises have a small territory in which they graze, and when two of them meet face to face, shit gets real. These tortoises will fight over resources, biting, ramming, and throwing one another with surprising ferocity for a reptile the size of a bar of soap (they can saaamelll what the Rock’s cooking!). You are probably asking yourself: can you see video of these tortoises beating the shit out of each other? Of course you can: what would the internet be without on-demand tortoise-on-tortoise violence? This is a video of two female Karoo padlopers fighting, paired with some appropriately dramatic music. This is a video of two male Karoo padlopers fighting with music that sounds like it’s from Super Smash Brothers—Final Destination, padloper only, no items.
The only time Karoo padlopers interact in a constructive way is during the mating season, which occurs in summer. After copulation, females dig nests in sheltered places such as beneath cliff sills or under large bushes, providing some protection from predators. Female Karoo padlopers lay only one egg at a time, a fact they should be grateful for, as their eggs are proportionally gargantuan. Each egg grows up to 35 mm (1.4 inches) long, nearly a third of the female’s total body length. Laying one of these eggs would be like taking a shit the size of one of your thighs (something I believe happened to me once after an over-ambitious Taco Bell run—I don’t recommend it).
Grazers and Gardeners
Karoo padlopers are herbivorous, with a preference for the leaves, fruit, and flowers of low-lying shrubs. They supplement their diets with osteophagy, chewing on bones to extract precious minerals like calcium from them (which is badass as hell). With the threat of death from above looming constantly, you’d expect these tortoises to chow down on the first hunk of greenery they see before scuttling back to safety. Surprisingly, though, Karoo padlopers choose their produce carefully and spend most of their active time scanning their surroundings for specific plants. They eat ten different species, some of which, like plants in the genus Hermannia, are rare.
This picky diet may actually hint to a kind of partnership between Karoo padlopers and the plants they eat. Most flowering plants require assistance from animals to spread their offspring. Animals can transport seeds over long distances and provide them with extra nutrients on the way out (i.e. shit). Tortoises generally have relatively gentle guts, and as a result they make for excellent seed dispersers. Karoo padlopers are no exception: seeds that pass through their guts often germinate, especially those belonging to the Hermannia species they love to eat. Because they spend so much time under cover, these tortoises can carry the seeds they eat to areas with ample shade and runoff. These features can be vital to plants, especially in times of drought, so they may rely on the Karoo padloper to survive harsh conditions.
While it may sound gross or pedestrian, Karoo padlopers and their favorite foods have the same kind of symbiosis as more glamorous partnerships: bees and flowers, clownfish and anemones, guys on Tinder and the fish they’re holding in their profile photos. You could even see this as a kind of gardening, with the tortoises harvesting their favorite plants and spreading them across the landscape. While other larger herbivores may eat these plants too, only Karoo padlopers can reliably transport these seeds to the spots that best suit their needs; without the tortoises, the rest of the ecosystem may suffer.
Protecting the Karoo Padloper
Once considered common in their range, Karoo padloper populations have rapidly declined by 35% in the last 25 years. Currently classified as Endangered, the International Union for the Conservation of Nature (IUCN) believes that without serious intervention on their behalf, the species’ population may drop by another 60% in the next 50 years (much like the number of people who will get my references to the Rock’s wrestling career), putting them at major risk of extinction. Population surveys have found that Karoo padlopers have disappeared from 30 of 35 locations where they were once common, and only one population still harbors significant amounts of both males and females. Even worse, only 5% of Karoo padlopers surveyed are juveniles, suggesting that either hatchlings don’t survive for long after birth or adults aren’t mating. This could lead to a population disaster called over-maturity as adult tortoises age and die.
The plight of the Karoo padloper is shared by many of its tortoise kin. 82% of tortoise species surveyed by the IUCN are at risk of extinction, ranking them amongst the most-endangered terrestrial vertebrates. Like the Karoo padloper, tortoises often fill important ecological niches, and their ecosystems degrade in their absence. In the Galapagos, for example, European colonizers hunted giant tortoises voraciously, driving four of the archipelago’s fourteen tortoise species to extinction and crashing the population of all tortoise species on the islands by 95%. In the absence of tortoises, the freshwater wetland species that relied on them for seed dispersal died out, and viable wetland habitats vanished completely from some of the islands. If tortoise species vanish from South Africa, the same kind of collapse could befall the Succulent Karoo.
Human development in the Karoo has played a major role in the Karoo padloper’s endangerment—surveys have shown that half of the species’ range has been degraded by human activity. Mining for copper, quartz, diamonds, and even uranium all occurs within the Karoo, and surveys have recently discovered gas-containing shale beneath it, potentially attracting fracking operations. One less obvious way that human development has endangered Karoo padlopers is by enabling their top predators, the corvids. While crows and ravens naturally prey on Karoo padlopers, human development has boosted their populations and given them tools with which to wreak havoc upon their prey. Telephone poles provide excellent perches for corvids, while garbage and dead livestock provide them with an all-you-can-scavenge buffet.
Corvids, such as the pied crow (left) and white-necked raven (right) act as major predators of the Karoo padloper. These birds use their intelligence and flight to break open tortoise shells, generally by dropping them from a great height. While native to the area, human activity has caused these species’ populations to boom, posing a threat to padlopers. Image Credit: Left: Kip Lee Yap under CC BY-SA 2.0. Right: Yathin Krishnappa under CC BY-SA 3.0.
Of course, the Climate Crisis also plays a role in the Karoo padloper’s endangerment. Straddling the line between grassland and desert, the Karoo is highly-sensitive to changes in rainfall, and as such Climate Change has the potential to drastically imbalance the ecosystem. Rising temperatures and changes in rainfall patterns in the Karoo has caused it to become encroached by desert in some places and grasslands in others. Karoo padlopers only eat shrubs, not grasses, so if grasses crowd out other forms of vegetation, the tortoises will starve. Grasses also attract ranchers, whose livestock can overgraze the land and further apply pressure to native vegetation.
The Climate Crisis in the Karoo has also taken a major toll on the people who live there. Droughts in the area have become unbearable in recent years, killing people, crops, and livestock. A recent drought from 2015 to 2020 affected more than 20 million hectares of land in the Karoo, contributing to tremendous famine and poverty; 2015 and 2016 alone saw the loss of 30,000 jobs in South Africa’s agricultural sector. Ranchers often respond to drought conditions by selling off most of their cattle, as they recognize that many of their animals will not survive the harsh conditions. When this happens simultaneously across an entire region, the price of beef crashes, and ranchers face astronomical economic losses. The only other option ranchers have, though, is to watch their cattle starve to death.
I mention the economic impact on farmers and ranchers in the Karoo not to sideline the Karoo padloper, but to highlight the interconnected ways in which the Climate Crisis causes crises. The same force that has driven Karoo padlopers to the brink of extinction has also contributed to massive poverty and famine across vast swaths of equatorial nations like South Africa. It is responsible for apocalyptic wildfires in California, for sea level rises in places like Polynesia and the coastal United States, for coral bleaching across the Pacific, for the spread of mosquito-borne illnesses north and south of their traditional ranges, and, yes, for the endangerment of this one particularly-important tiny tortoise.
I often feel overwhelmed when I think of the gargantuan scope of the Climate Crisis, but I also feel a sliver of hope. So many problems take up root in the Climate Crisis that stopping it will also solve many other issues, even ones that seem unrelated. Choosing to safeguard the climate from human exploitation will help everyone in the world, even in ways that we could not possibly have imagined. We can fight the Climate Crisis in a lot of ways, especially by pressuring governments and corporations to eliminate emissions and remove carbon from the atmosphere. Doing so will not only protect the Karoo padloper, but will make life easier for just about every living thing on Earth.
Apart from the existential war on the Climate Crisis what can we do to protect Karoo padlopers? To start, we can find them: activists and researchers have conducted population surveys across the Karoo to identify what strongholds for these tortoises remain. Without knowing where Karoo padlopers live, we can’t meaningfully protect their habitats from mining and fracking. The padlopers, for their part, have not made surveying them easy (they do dress up as rocks, after all), but many activists, both professionals and volunteers, have spent hundreds of hours combing through the wilderness, mapping out the species’ remaining habitats to identify what areas need the most protection. Researchers have even used imaging satellites to map out vegetation cover and other vital climate variables within the Karoo. This data can give conservationists a top-down view of how the landscape changes over time, helping them to identify hotspots of encroachment and desertification.
In conjunction with these surveys, conservationists are working to promote sustainable land usage in the Karoo. The Karoo has supported human settlement for tens of millennia, and with more sustainable practices humans can once again find harmony with their environments. One conservation organization, the South African Endangered Wildlife Trust (ETW), has launched the Karoo Forever program, which is designed to train farmers and ranchers how to use their land in a way that most benefits both their livelihoods and their ecosystems at large. At the same time, the EWT is combating fracking and uranium mining within the Karoo to prevent pollution and habitat destruction. To learn more about the EWT’s work in the Karoo, you can visit their website here. You can donate to help further their conservation work as well (though if you do make sure you designate your donation for the Drylands Conservation Program).
The Karoo padloper shows us that even the smallest creatures can have huge impacts on their ecosystems. While tiny and quaint-looking, these tortoises help to strengthen one of the most-diverse ecosystems on Earth—if we lose them, the plants that rely on their curation may follow. The Climate Disaster and human resource exploitation has the potential to not only wipe out the Karoo padloper, but thousands of species that inhabit the Succulent Karoo’s sanctuary of biodiversity. While we face many challenges of our own making, we also have plenty to hope for: humans have lived in the Karoo for hundreds of generations, and with a few changes to our behavior, we can re-stabilize the balance of nature in this most-important region for generations to come.
Sources and More Information:
Critical Ecosystem Partnership Fund. "Succulent Karoo". Conservation International.
Loehr, V. J. (2024). Personal Communication
Low & Rebelo (1996). Nama-Karoo Biome. South African National Biodiversity Institute
Consider Nature is written and published by Stephen Goralski. Editors for this article included Benjamin Gamble, Jesse Cristoforo, and Oli Platt. Our web designer is Oli Platt. Olmungandr, the Consider Nature logo, was made by Maxwell Schumacher.