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Into Africa: The Southern Namib Desert of Namibia

Keep up to date with Geography Department Chair Jill Heaton's travels to study lizards, tortoises and snakes of Namibia, Africa.

Jill Here! The time is going way too fast. After spending a week in the Kunene and the northern Namib Desert we headed south to explore the southern reaches of the Namib. We met up with my longtime friend and colleague Professor Jim Juvik (Geography, University of Hawaii at Hilo and Senior Conservation Scientist for The Turtle Conservancy) to hunt for the elusive and rarely seen Nama Padloper (Chersobius solus). The Nama Padloper is listed as Vulnerable by the International Union for Conservation of Nature, Endangered by Tortoise and Freshwater Turtle Specialist Group, and the Turtle Conservation Coalition list it as one of the world's 25 most endangered turtles. I admit...I seriously doubted our chances of seeing this species, but I was game to try. Who doesn't want to go searching for one of the world's rarest, most cryptic and elusive endangered species?!?!

I promise to provide the big reveal before this blog is over, but it would be remiss if I didn't talk about all of the other amazing reptiles we saw. To start with saw three of our girdled lizard study species while on this trip, including one species so unstudied by science that it is known from only a handful of locations.

2 researchers with a lizard

Jon DeBoer and Anette-Stella Mbango (Namibia University of Science and Technology Honors Student) holding a Jordan’s girdled lizard (Karusasaurus jordani) before releasing it back to the wild. Unlike the Karoo girdled lizard (see photo below) the Jordan’s does not cross over the Orange River.

Jordan's girdled lizard being measured

One of the many photos we take of all the lizards we capture for further morphometric analyses back in the lab using computer software such as JMorph.

Campbell's girdled lizard

We will be the first scientist to attempt to study Campbell’s girdled lizard (Namazonurus pustulatus) in the wild. This was the first time I had ever seen one.
[Text on image: Namazonurus pustulatus, Campbell's Girdled Lizard, Jon C. DeBoers]

Lizard in a crack

The Karoo girdled lizard (Karusasaurus polyzonus) is one of the most widely distributed girdled lizards, found mostly within South Africa, but it does interestingly extend north over the Orange River into Namibia. The Orange River is a geographic barrier to many reptile species, but we are hoping genetics will help answer this riddle for us. On the right here is a Karoo girdled lizard, as we see most girdled lizards, tucked into a crack with their formidable tail protecting their body.
[Text on image: Karusasaurus polyzonus, Karoo Girdled Lizard, Jon C. DeBoers]

Amazingly, we saw three different adders - the Horned Adder, the Many Horned Adder, and the Desert Mountain Adder. Yes, these snakes are venomous. I was walking through a dry wash when I came upon the Horned Adder sunning itself, Jon found the Many Horned Adder in a rock crevice while searching for lizards, and Anette was about to look under a rock for a Nama Padloper when the Desert Mountain Adder popped its head out.

Horned Adder snake

The Horned Adder (Bitis caudalis) is widely distributed in the arid parts of Namibia, Botswana and South Africa.
[Text on image: Bitis caudalis, Horned Adder, Jon C. DeBoers]

Left: Many Horned Adder, right: Jill with snake

Check out those many horns - 2-4 horns above each eye! The Many Horned Adder (Bitus cornuta) has a very restricted geographic range that includes only the most southern Namib desert – Namaqualand and portions of the Succulent Karoo.We keep a snake stick and snake tongs with us at all times so that we can safely handle venomous snakes. The Desert Mountain Adder (Bitis xeropaga) has a very restricted geographic range in Namibia and South Africa – interestingly it is one of the species that has managed to live on both sides of the Orange River.
[Text on image: Bitus cornuta, Many Horned Adder, Jon C. DeBoers]

Namibia is home to an amazing diversity of geckos (nearly 60 species in total with half of those endemic). Geckos are Jon's real passion, and the trip south did not disappoint. The taxonomy of many of the geckos in Namibia remains unresolved at best, confusing a worst, and identifying individual species can be time-consuming, in some cases very close examination of toes pads, or even in some cases requiring DNA analysis.

Left: Angulifer gecko and its toes

[Text on image: Chondrodactylus angulifer., Giant Ground Gecko, Jon C. DeBoers]

Giant Ground Gecko and its toes

[Text on image: Chondrodactylus sp., Giant Ground Gecko, Jon C. DeBoers]

Speckled thick-toed gecko

[Text on image: Pachydactylus punctatus, Speckled Thick-toed Gecko, Jon C. DeBoers]

Western Spotted thick-toed gecko

[Text on image: Pachydactylus serval, Western Spotted Thick-toed Gecko, Jon C. DeBoers]

The big reveal...yes, in the end we found not just one, not just two, not even three or four, but amazingly five Nama Padlopers. As these guys are very small (a full grown adult is just 100-150mm or 4-6"), very flat (40-60mm or 1.5-2.3" high), very cryptic (the same color as their background), live under rocks, and like all tortoises they spend most of their time inactive, we spent a lot of time looking under and between rocks. Since these guys are endemic to just Namibia, restricted to a very small known geographic distribution, and endangered you will probably notice that we did not share our InReach Garmin track on the web so as not to reveal where we located them.

Jon found the first Nama Padloper and the celebrations began. Dr. Juvik could not have been happier. It was the first one he had seen in the wild since 2006...and he has been searching for many of those years in between.

holding padloper, close-up of padloper

On the left Dr. Juvik holds the first Nama Padloper found. Doesn’t Jon take amazing photos! This is a close up of the first Nama Padloper that we found, a full grown male. Despite the mostly desolate landscape the first real rains in nearly eight years (just 36mm) had occurred just a few weeks prior and if you look close you can see that he has been feasting on green vegetation – notice the green on his mouth.
[Text on image: Chersobius solus, Nama Padloper, Jon C. DeBoers]

Jill, Jon and Dr. Juvik holding padlopers

left: Dr. Juvik, myself, and Jon happily celebrating the first Nama Padloper find. right: Here I am holding the two smallest Nama Padlopers that we found, carapace lengths (the back shell) were 47 and 67mm, respectively.

Thanks for reading! Keep an eye out for future posts as the research continues!

Jill Heaton holding a lizard