Category Archives: field biology

Psssst….That’s My Torchlight!

A bright torchlight is a must-have for a bat-eared fox field biologist. With a bright torchlight one can easily identify the owner of a suspicious pair of eyes (particularly, owners with dagger sharp horns) and avoid walking into the grasping branches of thorny acacia thickets. Most importantly, a torchlight helps when following a battie during a nocturnal follow. Information collected during follows give us an idea about batties’ diet, territory usage, and social interactions with other foxes. I can keep the spotlight on my focal fox as it dashes up the side of a sand dune or through a maze of driedoring bushes. Occasionally, a fox decides to takeoff like Superman, and it is very challenging to keep up with them when I am only allowed to follow at a “non-threatening” speed-walk. Mostly, my torch helps me to feel safe – it makes the night almost familiar to me, and is a constant reminder of how visually-centered we are, as human beings. There is no way my other senses would compensate for the absence of my torch at night.

From the beam of my torchlight I have observed foxes locate insects by integrating information from multiple senses. Like all canids, the senses of smell and hearing are wonderfully developed in bat-eared foxes. A fox will pause, sniff, and turn its head and ridiculously large ears around before dashing off to gobble up termites, pick a caterpillar out of a bush, or even dig up a mouse hole. By turning their large ears about foxes hear even better in stereo (this is called binaural hearing) and can focus on their prey items. While the foxes’ ears and nose do help them locate insects, it doesn’t quite always give them the balance I expect. For example, on a particularly nippy winter night I observed one of our foxes, Bain, digging up ant nests. He picked around a bush, sniffing and swiveling his ears about before pouncing a bush and digging it up. A couple of times he dug too deeply for ants, and then fell head-first into the deep hole he had just dug. It was impossible not to laugh!

Avoiding trouble by finding batties in daylight...

Avoiding trouble by finding batties in daylight…

During a follow a fox sometimes spends just as much time patrolling its territory as it does foraging, and possibly a fox uses smell to locate familiar places in their territory. Just as I use a torch to light up the night to make things familiar to me, fox urine is quite useful when marking over other fox pee or on termite foraging patches. Ilor, in particular, travels several kilometers during a follow. He will urinate on a random interesting spot after sniffing it, then another spot, and another, and so on. Occasionally foxes are known to wee on researchers boots or research equipment as well. This is how my field torchlight came to smell. I had set down my torch to feed Ben raisins, but Ben had other ideas. He came up to the torch, sniffed it, lifted his leg, and “pssst,” my torch now stank of battie pee. I still am not sure if I should be offended or happy that Ben claimed me as his own… I of course later sanitized my torch, but I still advise not smelling it too closely.

Threesome at Pharside (A tale of 3 foxes)

Escobar

Escobar, but no Emmental

On a cold winter night, I was walking around Pharside Dam as I wanted to just check in on Escobar (one of our habituated males) in the area. After I called for about 5 minutes, he pitched up from behind a grassy patch and waited for some raisins. Happy that he was looking so good, I left Escobar around and started my search for Emmental, the other habituated male in this part of the reserve. We hadn’t seen Emmental for a while despite searching on a regular basis, so alarm bells were starting to ring. My steps took me on a big loop in the area, without much luck.

As I was walking back on the road, I spotted eyes in the distance. I took my packet of raisins out and crinkled it, hoping this pair of eyes belonged to one of “our” foxes. It was indeed a habituated fox, but not a battie! It was Ray, the Cape fox (yes, they all come with name tags)! He came running at me for some raisins. With winter on us now, foxes are all super eager for this treat! I stayed with Ray for a while when Escobar found us again.

Ray, the Cape fox, looking hopeful and apprehensive.

Ray, the Cape fox, looking hopeful and apprehensive.

I was getting rather excited and curious about how these two species will interact. Batties are slightly bigger than Cape foxes, and from the few interactions we have witnessed, they seem to be dominant. As usual, Escobar chased Ray away immediately. Definitely, these raisins were his to eat! He had to stay on his toes though, as Ray kept hanging around, hoping for a lucky raisin, and it was only Escobar’s growling and puffed-up tail that stood between him and the juicy treat.

Escie defending his stash

Escie defending his stash

But Pharside still had surprises in store for me that night, as another batty suddenly approached. To my delight it turned out to be Emmental! He was looking extremely healthy and robust compared to Escobar, so I was certain Escobar would now have to give up his stash. Escobar thought so too. He crouched down, growling, tail raised and puffed up, in a very submissive position. But within a fraction of a second, the tables were turned. Escobar jumped up and started a fierce fight with Emmental, eventually winning and chasing the bigger fox away. And for the next 30min, I was in the company of these three foxes.
When Emmental finally started to drift away, I simply could not follow him, as both Ray and Escobar were on my heels! It was a very peculiar stand off, with both of them circling me whenever I paused for a second, and Ray trying to keep his distance form Escobar. I was impressed by Ray’s tenacity.

Walking back to the car, I started wondering. How is dominance established between batties? Is the hierarchy stable or variable through time? What are the benefits of being dominant and the costs of being subordinate? Is it access to the best foraging spots? Or to more mating opportunities? These animals tend to forage together so socially – is there even a proper hierarchy? Is there any way that a Cape fox could beat up a battie? And I realized I had my work cut out for me: I need to habituate plenty more foxes during a very cold, long winter…

Batties and boxes — Sam

Returning to the Kalahari to work on batties becomes a more daunting prospect when the research project is your own. There are considerations such as whether or not your experiments are feasible in the field and – importantly! – whether the foxes are going to co-operate. My idea was perhaps a tad complex… I designed a series of memory trials that required the foxes to investigate an experimental arena with a bunch of little boxes in which they had to dig no less than three times in the space of 2 hours. And, if they complied on night one, I needed to repeat the feat with the same foxes multiple times. Naturally, I was nervous.

Fortunately, batties are very curious. To my relief, they’ve taken to the task at hand with alacrity and enthusiasm. And to my increasing amusement I am now witnessing the ways in which that enthusiasm manifests itself. For some, they are quite content to sit nearby watching me feverishly setting up the camera and arena, eager to dig up the raisins buried in the little boxes. The fact that they hang around at all is somewhat of a minor miracle – these are wild animals and they have an entire reserve to disappear off into should they so choose. The reactions of others has been a fascinating reflection of their very unique personalities. Our highly intelligent vixen Donna, for example, lacks the patience to ever actually complete a trial, choosing instead to trash the arena like a surly teenager before stalking off, growling, into the bush. Which is why I found it particularly frustrating that Donna, not content with merely making my life difficult when she was in the spotlight, decided she needed to gate-crash someone else’s trial as well.

The fox in question, Bertha, is the mum of our current batch of pups and — despite her efforts at finding “me-time” — a difficult subject to get on her own. Two of the pups (lets call them Bane and Pestilence), have made it their personal mission to interfere as much as possible with the serious business of science. They excel at… er… endearing things like untying my shoelaces as I’m manning the camera, or rummaging through my rucksack in the middle of a trial when I can’t stop to move it. Thus, having accomplished the difficult task of getting Bertha on her own for a trial, the last thing I wanted to see midway through trial 1 was Donna. 

Bertha about the business of finding hidden rewards

 Donna’s approach was marked by a sudden business-like growl from Bertha. Now, in the past, Bertha has always been submissive to Donna, but with the arena in front of her she wasn’t having any of it. She growled meaningfully in Donna’s direction and stood her ground, one paw possessively placed in a box. Donna, being who she is, couldn’t stomach this affront and came striding towards us, intent on her mission of sabotage. Seeing that she was about to start a fight, I moved to a spot in between her and the arena to block her passage, sporting my best Gandalf-like “You shall not pass” face. Realising that neither myself nor Bertha was going to allow her access to the arena, Donna gave the only respectable response that a highly-strung vixen could give in this sticky situation. She screamed.

She literally sat down, a couple of meters from my foot, and yowled at a pitch that predicted perforated eardrums before the night was through. Now, I know this sounds like a bizarrely traumatised reaction, and I could be accused of meddling unethically with our wild animals’ emotional well-being. However, screaming is a form of self-expression peculiar to Donna. I know this, because she also does it if she happens to be around when one of the pups is getting attention from us, or if you simply aren’t paying enough attention to her directly, or whatever other slight to her person, real or imagined, is underway. I chose to ignore her (and deal with my eardrums later). Bertha too, after casting the other vixen a bemused glance, seemed happy to disregard her wailing, so I resumed filming with Bertha enthusiastically digging for raisins.

Donna continued her tirade of abuse until she realised the tantrum was not affecting us, and then carried on foraging for termites nearby, casting back the occasional disparaging glance. Well, I’d like to think that perhaps she’ll be a bit more enthusiastic about her own trial next time, but likely, she’ll just trash everything like a true drama queen. And the sad fact is, this juicy information will only be a dry blip on my computer screen when I enter the night’s data – “Trial 1 – poss soc interference (DON obs)?”

Fear of the dark — Rebecca

The start of a PhD poses many challenges, and I am sure I am not alone in the fears I have… will I be able to collect enough data in time? Will I be able to answer exciting new questions? But the embarrassing fear I didn’t even consider until a few weeks before embarking on this adventure is my fear of the dark.

For my first week in the field I was pleased to learn I would accompany Keafon and Sam at night for training, so my dreaded solo trip was postponed. However, even then I began to wonder how I would ever feel comfortable with the eeriness of the dark, where strange shapes can appear and unknown noises play with your mind.

P1060142

My only protector in the dark Kalahari nights.

One week later it was time for my first solo outing. As I set out in the dark my heart was racing, but I kept telling myself, you can do this! Just for a moment, I turned my spotlight off and embraced the darkness. It was an overcast night and the blackness engulfed everything. But turning the light on and off as I pleased meant I was in control of the dark… But last night was different.

Following Ernie at high speed kept me more than occupied and the thought of the dark didn’t even enter my mind, when suddenly, my torch batteries failed. After a few deep breaths I reached into my bag and felt around for new batteries. I slowly placed them into the torch, breathing a sigh of relief in anticipation of fresh, bright light. After a small pause, I click the torch on and……nothing…….darkness. Not a problem, still another four newly charged batteries to go. Again, reaching into the bag I found the batteries and carefully placed them into the torch, but still…darkness. I could feel my heart thumping in my chest, and I wondered how long I should leave it before calling for help. All that kept running through my mind were the stories Keafon and Sam had told me about snakes. I had horrid visions of being surrounded by masses of snakes. After 15 minutes of sitting alone in the dark, desperately trying to get my torch to work, I decided it was time to call Keafon. As the car’s headlights appeared on the horizon I breathed a huge sigh of relief. My time in the dark was over.

Luckily, after only 10 days in the field, I am in love! The foxes and their individual characters are simply amazing and this adventure with them is going to make any fear easy to overcome and most certainly worth the bumpy ride of facing those fears head-on. This morning, as I sit here and reflect on my experience I am pleased my batteries failed; it forced me to face my fear and realize the dark isn’t so bad… and the feeling of being the only person left in the world is pretty amazing. I imagine there are not many places left in this world where one can have that feeling!

Puppy Love — Keafon

The breeding season has finally yielded excitement in the field as one of our very own, Bertha, had a litter of adorable pups! Perhaps even more surprising is the fact that no one saw it coming, least of all, not from Bertha, who is notoriously shy and showed no signs of pregnancy. The same cannot be said of Garbuncle, whose thick fur and mood swings got us fooled into thinking she was pregnant, but these “signs” turned out to be false alarms.

The pups, who have been sheltering in dens, are now beginning to venture into the wild in search of food. The recent drought presents a major food challenge for both mom and pups, who can no longer be sustained by milk alone. As they wander far and wide in search for food, locating individuals to do focal behavioural studies on is getting a bit tricky as their territorial boundaries have expanded. It is no longer unusual to spot new and unfamiliar neighbours that roam right into our nightly sessions. Some of our “own” foxes, like Ilor, are even skipping reserve boundaries altogether and venturing deep into nearby farms.

During a late night search for Bertha, I stumbled upon what at first looked like a wild cat, bouncing about in the bushes like a ping pong ball. It was only when it stopped and peered intently at me with small black eyes that I realized it was a pup! I had not seen any of them until now and needless to say, it was love at first sight. Soon enough, I found myself surrounded by three pups and their mom, all eager for some raisins.

Bat-eared fox pup

Ears that only a mother could love?

I could see a new (thesis) chapter unfolding right before my eyes, as several questions came to mind: how are they coping in this climate of drought? Given that lactation is likely to increase Bertha’s nutritional requirements, how does her feeding frequency and meal constituent compare to her pre-maternal state? Feeding demands made by pups will no doubt influence her feeding patterns. I now have the opportunity to investigate these and more; such as the quality of maternal care, by noting down factors (grooming, nursing/feeding, ‘pup-protection’ etc) that will help me answer these questions. Sadly, all my proverbial eggs are in one basket for now — Bertha’s. I will be keeping a close tab on Bertha and her brood for the next couple of months as I get more acquainted with the pups.

A double edged sword — Ruan

Similar to other PhD students in behavioural ecology, I spend months in the field and have to sort out the various and inevitable problems that come with remote fieldwork. Our supervisors trust us to do a good job of keeping the project going and getting all the necessary data. They cannot really keep a heavy hand on us – email correspondence is about the only way of managing contact. Except when you hear the words, casually dropped, “I am coming to the field.” This almost always strikes fear into the heart of a student. What are they going to think about the progress I made? Will they agree with the way I sorted out some of the problems? Would they have done things in a similar way? Will they be happy?

 

A hard-working PhD student in action

A hard-working PhD student in action. Photo credit: Elizabeth Wiley

Approaching my seventh month in the field, I was anticipating the excitement of the breeding season that was expected to be in full swing by the time I arrived. Judging by the number of insects flying into my face and up my shirt, I did not think we were experiencing a drought. However, my worst fears came true…there was no evidence of breeding, and no pups! This is definitely not a good sign for someone whose PhD is based on paternal care. The extreme conditions and apparent food shortage (?!) have had a detrimental effect on the foxes’ attempts at successfully producing pups this year. Whatever the reasons might be, I needed some guidance, and the remoteness of our study site has made contact with the outside world challenging to say the least. I was actually relieved to hear my supervisor was planning on dropping by. Maybe she could steer things in a better direction.

We had endless discussions on potential solutions to my dilemma… As part of such a new project, I was a little restricted in terms of finding new angles within the range of data we have collected so far. We finally settled on the “simplest” solution — I would include home ranges and marking behaviour, mediated by hormones, in my thesis. Of course, this easy answer now meant I have to follow foxes for the entire night in order to get a better idea of the distances these little guys travel. I started to prepare for endless long nights in the field.

And then it happened… one of our vixens, Bertha, took me to a secret den, where I found our first three (and so far, only) pups of the season. The excitement was tangible, even if I was abashed at being ‘out-foxed’ by the apparently virginal Bertha for a while. Of course, my supervisor left just after this wonderful event, and the problems are lining themselves up yet again. We’re doing full-night focals to collect that extra data. But very, very soon, we will be able to follow the first ‘project’ pups in our nightly observations. And we remain at the combined mercy of fickle Mother Nature and technology, constantly messing with our most carefully made plans.

 

Finally -- bat-eared fox pups enter the picture!

Finally — bat-eared fox pups enter the picture! Photo credit: Ruan de Bruin

Is the third time the charm? — Ruan

An experienced field researcher by now, I had certain expectations of my third trip to the field this year. These expectations were quickly shattered as I, once again, realised that change is the only constant. My body – used to subzero winter temperatures in the Kalahari – went into a mild state of shock when I returned to spring temperatures reaching 40°C. The heat is, quite simply, debilitating. Simple tasks like eating dinner become a battle as I try to force nutrition into my body that was already sweating like a hippo in a sauna. I have a new appreciation for nocturnal work under these conditions!

The batties have shed their gloriously fashionable winter coats and their true size – or lack of it – is now revealed in their scraggly summer fur. They are almost half the size they were when I left. The lack of rain and extreme temperatures has also resulted in some vegetation changes. The tall sour grass that used to cause several “exciting evenings” is all gone and the field is now flat, open and bare. This makes finding the foxes a lot easier and these little Houdinis are far less likely to do a disappearing act on me this time around. Last night, I had the opportunity to see a “dog” and mouse situation, where the fox I was following locked eyes with a passing rodent. What ensued was some tail-raised-dust-cloud acrobatics as Blackie was determined to put mouse on the menu. After several minutes of traversing in all directions, the battle finally ended in a faint squeak as the mouse was defeated. Blackie proudly looked around before he indulged in his glorious feast.

I am excited (and stressed) to be back with my foxes and anticipating that the breeding season is going to ensure me some interesting times in the near future… Hopefully some of these tiny little foxes will prove man enough to father some adorable pups.