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Mozambique Diary: Is this tortoise broken?

An adult Hingeback tortoise (Kinixys belliana) from Gorongosa. What looks like a wound on its carapace is a flap of skin that allows the shell to close and protect the hind legs and tail.

An adult Hingeback tortoise (Kinixys belliana) from Gorongosa. What looks like a wound on its carapace is a flap of skin that allows the shell to close and protect the hind legs and tail.

Some time ago I was driving in Gorongosa when I noticed a large tortoise laying in the middle of the road, stuck upside down in the mud. The animal was alive but had what appeared to be a large wound in the posterior part of its cracked carapace. There were fresh tracks of a civet all around it in the mud, and I assumed that the civet found an injured tortoise (I didn’t think a civet could do it itself) and was hoping to eat it. I pulled the animal out of the muck and only then recognized what I was looking at – the tortoise was not injured at all, and what I took for a wound was a flap of skin that connected the front part of the shell with its movable back. Because it was not an ordinary tortoise, but a Hingeback tortoise (Kinixys), a member of a remarkable group of reptiles that are capable of closing shut the back of their shells to protect the hind legs and the tail. This, combined with the head tightly pulled into the front of the shell and blocked by its heavily armed front legs makes the hingeback tortoise virtually immune from attacks by smaller predators. Judging by the dense trail of civet tracks around the tortoise it seemed that the mammal had spent a lot of time in frustration, unsuccessfully trying to get to the soft parts of the reptile.

A juvenile Hingeback tortoise; its hinge is not yet developed.

A juvenile Hingeback tortoise; its hinge is not yet developed.

Although the movable carapace is a great way to protect the rear part of the body, the flap of skin that connects the two components of the carapace is a favorite location for another enemy of the tortoises to attack – the ticks. Every tortoise I found in Gorongosa carried several huge, heavily armed ticks (mostly of the genus Amblyomma), whose body shape and sculpturing was surprisingly similar to that of the tortoise. Carrying a bunch of blood-sucking ectoparasites is no fun, but the burden of being drained by them is probably particularly heavy on smaller, younger animals. A few days ago I found a tiny Hingeback tortoise, one whose hinge was not yet fully developed, and it carried on its leg one of the largest ticks I have ever seen. It was as if I had a parasite the size of a football permanently attached to my body. I removed the tick from the tortoise, put one of the animals into a vial of alcohol, and applied some antiseptic to the other and let him back on his merry way.

An enormous tick (Amblyomma sp.) on the tortoise's leg.

An enormous tick (Amblyomma sp.) on the tortoise’s leg.

Hingeback tortoises are quite common in Gorongosa, and I see them often as they cross the network of trails. But across Africa their numbers are declining as the result of habitat loss and collecting for the pet trade. Every year about 20,000 of these animals are exported to be sold in pet stores in the US and Europe, and Mozambique alone sends out about 3,000 of these animals every year (this is the official quota allowed by CITES, the actual number is undoubtedly higher). Luckily, recently the importation of most of Hingeback species was banned in the US. The reason – ticks. Some of the ticks carry a disease which, while not harmful to the reptiles, is often fatal to cattle – the Heartwater disease, caused by rickettsia Ehrlichia ruminantium. And so, the same parasite that makes the tortoises’ life miserable may in the end help them survive in the wild. I guess you never know who your true ally is.

Tortoise tick (Amblyomma sp.) actually looks like a tortoise, and its opisthosma is almost as hard as the reptile's shell.

Tortoise tick (Amblyomma sp.) actually looks like a tortoise, and its opisthosma is almost as hard as the reptile’s shell.

Mozambique Diary: The stuff of dreams

Banded-legged golden orb weaver (Nephila senegalensis) from Gorongosa [Canon 7D, Canon 14mm, Canon MT 24EX twin light]

Banded-legged golden orb weaver (Nephila senegalensis) from Gorongosa [Canon 7D, Canon 14mm, Canon MT 24EX twin light]

Isn’t it fascinating that the same thing can be the subject of one person’s worst nightmares, and another person’s wildest dreams and desires? Nothing illustrates this point better than the Golden orb spiders (Nephila), which my wife doesn’t even call spiders – they are simply her Nemesis, clearly intent on luring her into their enormous webs and tangling themselves into her hair.

But today I had the pleasure of going into the field with two great arachnologists, Matjaž Kuntner and Ingi Agnarsson, who came to Mozambique with one dream and one dream only – to see and catch the largest orb weaving spider in the world, Nephila komaci. This species was discovered by Matjaž a few years ago among old museum specimens, but nobody has seen a live individual since. But there is an interesting twist to this story – the reason Matjaž and Ingi chose Gorongosa to look for this Holy Grail of arachnology was a small photo, a thumbnail really, of N. komaci that had appeared on the old Gorongosa’s website five years ago, two years before the species was officially described. We didn’t know where exactly the photo had been taken, but it had to be somewhere in the park.

We set out early in the morning to look for the elusive weaver, hoping that we might find it in the patches of sand forest in the southern part of the park. Alas, after several ours of trampling through the bush we came back empty handed, not in small part because of some confusion as to where the forest was, which made us end up miles away from our intended destination. But playing bait for lions for several hours this morning was not a complete loss, either. The spider men found a few interesting species, including a related species, the Banded-legged golden orb weaver (Nephila senegalensis). These are gorgeous beasts, huge and beautifully colored. Their orbs are often made of brightly yellow silk, hence the common name. A few years ago Simon Peers and Nicholas Godley used the silk of a related species from Madagascar to weave an extraordinary golden cape.

Tomorrow Matjaž and Ingi will continue their search, this time with a GPS and an even stronger desire to lay their hands on the dreamy arachnid.

A view from the other side (a guest post by Kristin)

The very first solifugid that I ever saw. When I posted this photo on Flickr, the always hilarious Brandi Schuster commented, “Solifugid. That sounds like the noise that I would make if I ever saw one of those fuckers in real life.” [Canon G10]

The very first solifugid that I ever saw. When I posted this photo on Flickr, the always hilarious Brandi Schuster commented, “Solifugid. That sounds like the noise that I would make if I ever saw one of those fuckers in real life.” [Canon G10]

“So, are you afraid of solifugids, too?” my husband asked, questioning me about my life long fear of spiders while writing his first book, The Smaller Majority. Now, I am not your stereotypical girl, revolted by and fearful of insects of all types. I love insects and pride myself on knowing more about them than most laymen. Consequently, I really didn’t want to admit that I didn’t know what a solifugid was, nor did I want to add any other arthropods to my shameful “eek!” list. Picturing something like an amblypigid, I replied, “Pfft, sheesh, phuff, no, of course not. Just spiders.” Little did I know.

The first time that I ever saw a solifugid was in South Africa in 2009. Long after nightfall, our group had finally made it to our accommodations – a research station in the hills of Cederberg. The mattresses were stained and soaked with things unholy, and bats were roosting and pooping in the rafters of the kitchen, but the real problem was the spiders. Big, hairy, and speedy.

Spider-free living. Hey, if I believed it, that was all that mattered. [Canon G10]

Spider-free living. Hey, if I believed it, that was all that mattered. [Canon G10]

It began to dawn on me that I couldn’t stay in that room, but we were hours away from any alternative. As I began to wrap my head around this puzzle, I heard commotion outside one of the rooms. Piotr was gasping things like, “Oh boy!” and scrambling for his camera gear in a way that suggested that he’d found something really “cool”, and our friend Maciej was pounding on the door, yelling in his thick Polish accent, “Corey! There’s a solifugid coming into your room!” The doors didn’t meet the floor, you see. Of course they didn’t. There was enough of a gap that the mouse-sized, spider-like thing that we stood staring at was able to skitter under Corey’s door without even ducking its head or pausing at chewing on a grasshopper.

The Verandah. Doesn’t it look delightful? Note the interesting choice to install a screen on a door that doesn’t meet the floor, and the lack of a screen on the window. [Canon G10]

The Verandah. Doesn’t it look delightful? Note the interesting choice to install a screen on a door that doesn’t meet the floor, and the lack of a screen on the window. [Canon G10]

So, I finally learned: solifugids look like a cross between a bleached mouse and a spider, and they live in dry regions in South Africa. Also, charmingly, they are carnivores. I slept in the car that night and the following morning we paid the spiders for our room and board. It wasn’t until 2 years later that my solifugid lessons resumed, at graduate level.

Again, I was in South Africa. Again, I was in Cederberg. Again we were staying in the type of accommodation that makes biologists “oooh” and “ahhh” and walk around, poking into corners with a junky’s avarice. Make no mistake- Cederberg is one of my favorite spots on the planet. It’s gorgeous and fascinating. It just needs some screens, and I’ll tell you why…
One evening, as the entomologists set out to see what could be found in the darkened crevices of the mountains, I deferred, pulled a couple of chairs to the middle of the verandah, poured some wine, made a snack plate, put my feet up, and opened a book.
It wasn’t long, maybe only a half hour of sipping, reading, nibbling, and pausing to feel the warmth of everything right, before things changed. A cat emerged from an unlit corner and as I leaned forward with an “Oh, hey kit…tie…”, I saw that it was stalking something. A mouse? I thought hopefully, naively. No, this was Africa. The cat was not chasing a mouse. What it was batting at looked like a mouse, to be sure. A large, bleached mouse that began to run like the wind. I froze, recalling platitudes- it’s more scared of me than I am of it; it wants to avoid me; it won’t climb my chair, or the walls, then lose its grip on the ceiling and fall down the back of my shirt collar…
As I was trying to calm myself with this mantra, the solifugid raced directly to my chair, and attempted to climb a leg. I jumped to stand on the chair- though, I couldn’t but note, nowhere near as quickly as the solifugid was moving. Supposedly, they can run over 6 inches per second, which earned them one of their common monikers- wind spiders- but I’m here to insist that when feral cats are chasing them, they easily set new PR’s.

A storm passes over the top of a mountain in Cederberg at the end of a scorchingly hot day. This place is worth every degree and every arachnid above my comfort level. [Canon 7D, Canon 14mm]

A storm passes over the top of a mountain in Cederberg at the end of a scorchingly hot day. This place is worth every degree and every arachnid above my comfort level. [Canon 7D, Canon 14mm]

The cat was in hot pursuit, so rather than struggle to grip my chair legs and race up to tangle itself in my hair, the solifugid bolted to another dark corner of the porch. Other than seeing the shadowy figure of the cat racing and pouncing, I had no idea where it was. I looked behind me at the door to our chalet. It wasn’t more than 3 feet away, but I didn’t feel confident that I could make it before the solifugid did, wherever it was.

Then suddenly, there it was, scrambling up the side of the wall and toward me without losing any of its breakneck speed, the cat trailing it along the floor. I may have screamed, I don’t know. What I do remember was cursing Piotr in my head- while trying to convince me that there was no need to sleep in the car during that first encounter, at the Spider Chalet, he had absentmindedly assured me not to worry, the solifugid wouldn’t climb anything. It was said with the distracted air of a man telling his wife that yes, he has noticed her haircut and likes it, so I should have known better.

Glorious Cederberg. [Canon 7D, Canon 14mm]

Glorious Cederberg. [Canon 7D, Canon 14mm]

As it passed over the door and zoomed back toward the floor, I knew that I had to act. I jumped from the chair and made for the door. The solifugid reversed course and came straight for me. I jumped back up on the chair (I learned later, when relaying this story to Piotr, who seemed to see it more from the solifugid’s perspective than mine, that they seek safety in shadow, and the shadow that I cast as I moved, intent on my own escape, made me an unwitting attractant.)
Confused, it turned to dart back toward the shadows again, and this moment’s hesitation allowed the cat to get a good whack in. The solifugid reared up and presented the cat with its enormous, open jaws, and lunged. The cat jumped backed, stunned and impressed. With another lunge for good measure, the solifugid took advantage of the cat’s reverence for its display and zipped into the dark. The cat followed, slowly- back in stalking mode- and I made my second jump from the chair, frantically fumbled the door open, and burst into the cabin, eyeing the gap fretfully and wondering why it wasn’t a priority anywhere in Cederberg to fashion doors to meet the ground.

I sat in the middle of my bed and aimed my headlamp like a sentry at the screenless window, which opened directly onto the verandah that I had just fled, and waited for the others to return from their night collecting. I tried to shut the window, but the heat was unbearable. After a day of baking at well over 114F in the sun, the cabin needed all night to cool down. Hours passed. Finally, I laid back. I opened a nearby book and exhaled. Cue something, of course. It was the cat, jumping in the window. Why? On the tail of the solifugid again? Why else would it have come in? This is what I had to assume. War rules.

I will never know if the cat, which soon exited through the kitchen, came in because it was chasing something. But what I do know is that entomologists can stay out in the dark for eons and, when they return in their exultant state, don’t think to wonder about overturned chairs, scattered snacks, and splayed books in the middle of the porch. They walk right by with their containers and baggies held up for rapturous inspection, like urbanites immersed in their cell phones, and seem startled to see you awake and upright, just before dawn- “Oh, hey baby- what are you doing up?”

Compared to a solifugid, this tiger spider (Argiope australis) seems like sweet, harmless bunny. [Canon G10]

Compared to a solifugid, this tiger spider (Argiope australis) seems like a sweet, harmless bunny. [Canon G10]