Monday, February 1, 2016

The Mara's Mighty Hunters

While driving home from obs one fine January evening, we were startled by a flurry of motion in the road – a black-backed jackal in hot pursuit of a springhare. We stopped the car to watch the lightning-fast chase. One wrong step from the hare gave the jackal the opening he needed; in the blink of an eye he’d scooped up his prize in his jaws and trotted off into the grass to enjoy his freshly-caught dinner.

The thrill of watching the hunt got me wondering about the other hunters who inhabit the Mara. Almost every prey animal in this vast grassland is built for incredible speed, so how do the predators who live here manage to keep up? Hunting strategies vary widely by species, region and prey, but I’ll cover some of the most common techniques for the Mara’s greatest hunters.


I’ll start with the critter that sparked my interest: the black-backed jackal. Jackals are opportunistic omnivores, which essentially means they will eat anything they can get their jaws around. This covers everything from insects, reptiles and rodents, all the way up to fully grown impala. For smaller prey, like rodents and the unfortunate hare whose demise we witnessed, jackals use their impressive agility to catch and subdue their food. For larger prey like gazelles and impala, jackals switch to a harrying technique to compensate for their small size – harassing an animal until it’s too tired to fight back, then taking it down with bites to the throat or stomach. Though they don’t hunt nearly as much as the obligate carnivores (animals which are only capable of eating meat) of the Mara, jackals have a hunting prowess all out of proportion with their size.


Like the jackal, leopards have a size disadvantage to many of the species they choose to prey upon. Weighing in at only 66-176lbs, leopards are outweighed by some of the larger antelopes that make up their diet. They make up for this with unparalleled stealth and jaw strength. Leopards stalk their prey by night, choosing to pounce at close range from the ground or dropping from trees onto their unsuspecting target. As we were lucky enough to witness, they can kill with blinding speed, using powerful jaws to crush their prey’s throat. Unfortunately, leopards are frequent victims of prey-theft by lions and hyenas due to their small size. To prevent this, they commonly stash carcasses in trees. If you’re wondering how much strength that would take, try dragging something that weighs more than you do backwards up a tree using only your mouth, and let me know how it goes.


Don’t tell the hyenas, but cheetahs are my personal favorite Mara hunter. Unmatched in elegance and, of course, in speed, the cheetah has definitely earned its place as the world’s fastest land mammal. Different sources give different numbers, but most experts I could find agree these lovely cats can break at least 60mph in a dead sprint. Everything about the cheetah is built for speed. Their spine is extra flexible to allow their legs to reach huge distances per stride. Their claws have lost the ability to retract in favor of acting like sprinter’s cleats to give them greater grip on the ground. Even their tails are adapted for use as a counterbalance, allowing cheetahs to cancel forward momentum in order to change directions more quickly in the heat of a chase. All of these finely-tuned adaptations pay off: cheetahs have a nearly unheard-of hunting success rate of 50%. The much-lauded lion has a success rate of only 17-19% when hunting alone, or around 30% when hunting in groups. However, there are drawbacks to their speedy build. Cheetahs are comparatively small and fragile, which mean as many as half of their successful kills are stolen by lions and hyenas.


They may not be the most successful, but lions are certainly the biggest and the baddest of the Mara’s hunters. Some males in East Africa have reached sizes of around 390lbs. Their impressive bulk means they can’t keep up with agile antelope in a test of speed, so they must rely on stealth instead. Lions hunting on their own will stalk their prey, taking advantage of the Mara’s tall grasses to hide them until they are within pouncing distance. Lions hunting in groups can get a little fancier, and employ tactics where one lion lies in wait while others drive the prey into an ambush. Though they have the reputation as one of the world’s mightiest hunters, lions actually prefer to scavenge whenever possible. They use their strength and numbers to shoo other predators off their kills and take the food for themselves. Typically, only a group of hyenas are capable of defending themselves at carcasses when lions come calling.


Last, but certainly not least, our own beloved spotted hyenas. Hyenas are possibly the world’s most infamous scavengers and carcass thieves, but it is a reputation that is only partially deserved. Hyenas do indeed scavenge and steal, but they are excellent hunters in their own right, killing up to 90% of their own food. Rather than employing speed and stealth like most of the Mara’s predators, hyenas rely on their powers of endurance. Hyenas are built to run at a steady lope for many kilometers, wearing their prey down until it is incapable of running any farther before eating it alive.

References:

Holekamp, K. E., Smale, L., Berg, R. and Cooper, S. M. (1997), Hunting rates and hunting success in the spotted hyena (Crocuta crocuta). Journal of Zoology, 242: 1–15. doi:10.1111/j.1469-7998.1997.tb02925.x

Kamler, J., Foght, J., & Collins, K. Single black‐backed jackal (Canis mesomelas) kills adult impala (Aepyceros melampus). African Journal of Ecology 09/2009; 48(3):847 - 848. DOI: 10.1111/j.1365-2028.2009.01173.x

http://www.sanbi.org/creature/black-backed-jackal

http://animals.nationalgeographic.com/animals/mammals/leopard/

http://www.cheetah.co.za/c_info.html

https://lionalert.org/page/predatory-behaviour

Monday, January 25, 2016

Serena's Lost Clan

Anyone born and bred in Virginia or North Carolina, as I am, knows the tale of the Lost Colony of Roanoke forwards and backwards. It’s the true story of colonial settlers who arrived in 1587, then disappeared only three years later, leaving no trace but the word “Croatoan” etched into a gatepost. Even now, there are only theories as to what happened to the 118 men, women, and children all those years ago.

ILLUSTRATION BY NORTH WIND PICTURE ARCHIVES/ALAMY
So what does a lost colony have to do with hyenas? Well, you could say that some of our hyenas have disappeared without a trace, and I couldn't help but draw parallels between them and the vanished colonists.

The saga began when our Happy Zebra hyenas moved dens in early December. Usually, when the clans change dens, it’s only a few days before we figure out where they’ve relocated. But after a week, two weeks, then three weeks had passed, we realized we might not find their new den for a long while. Now, almost two months later, I can say with confidence we have no idea where they are.

While historians are studying antique maps and archaeological sites to discover the fate of the Roanoke colonists, we hyena researchers are depending on radio-collar tracking, our knowledge (albeit, sometimes limited knowledge) of the territory, and strategic driving to find our clan. Best case scenario: we happen upon the active den one day while our on obs. 

Current scenario: after two months of searching, tracking, and hoping, we still haven’t found the den. But we have seen Pike the matriarch, Cosby, and a few sub-adults and older cubs in a particular field many times over. You could say this is our version of the “Croatoan” clue – an indication of where they might be, but alas, no luck yet. It’s a pretty big field to search.  

Just a section of the area we think they might be hiding. 
But all hope isn’t lost yet! We’re optimistic that we’ll either find the den soon, or they’ll move back to a spot we know. Until then, we’ll keep looking, hoping to solve our own Lost Clan mystery. Who knows? Maybe there’s even an “HZ” carved into an acacia tree somewhere....

One thing is for sure: we can't wait to see these goofy faces again!

Rummy!!
Cami taking the best kind of nap: an upside-down one. 
Jolly Roger rocking the mohawk. 


Thursday, January 21, 2016

Leopard Luck

The Maasai Mara supports an enormous amount of animals – for those of us from the suburban areas of the United States, where the wildlife pretty much consists of squirrels and the occasional deer, the sheer number of antelope we see on any given day is absurd. But what is the most shocking is the number of carnivores that live here. From dwarf mongooses (the smallest carnivore in East Africa, less than 14 inches long) to the famous lion, carnivores are absolutely everywhere. But the least common carnivores to see, of course, are the big cats. And of the big cats, the leopard is the most elusive.

Leopards are amazing animals – beautifully spotted, powerful, sporting a face that simultaneously makes us awwww in adoration and shudder with well-founded fear. They are stealthy, stalking their prey to within 10 feet before pouncing and killing with a stranglehold to the throat. They are impossibly strong – able to drag a carcass over twice their weight up into trees to protect it from other scavenging carnivores like lions. Leopards can vanish into grass half their height and reemerge over 60 feet away with none the wiser. These animals quite literally cannot be seen if they don't want to be seen.

That is what makes it so profoundly exciting that four days ago, we saw a leopard casually sitting on a prominent mound in our driveway, lazily flicking his tail as we drove home from our evening obs session.


Erin's family was visiting, and her brother John casually asked, "Is that a leopard on that mound there?" I looked, ready to declare it a lion or a hyena or literally anything else but a leopard, but sure enough, there it was! We were thrilled, snapping pictures and watching as it stood up, stretched, and began to walk up the driveway toward us. It passed within a few feet of the car and headed up the road.


As we were thinking about following it, a Mara miracle occurred – another leopard walked out of the tall grass behind the mound.


At first we mistook it for a cheetah, because this leopard was a bit smaller, and more gracile than the other. This led us to believe that the second leopard was a female, and the first a male.

To explain how ridiculous this is – leopards are typically encountered alone unless it is a mother with her cubs. Leopards are solitary, and males and females keep apart until mating, at which point they will tolerate each other for as brief a time as it takes to mate. Then they go their separate ways. So what we were seeing was the prelude to what might have turned out to be leopards mating. The female followed the male up the road (and we followed too, trying not to let them out of our sight) and up onto a grassy hill.


There, they spent about 10 minutes eyeing each other and growling softly in the backs of their throats. We weren't sure which one was growling, or if both were, but it was a sound I had never heard before and will likely never hear again. After the female circled the male several more times, the male snarled and chased the female away over another hill and out of sight, leaving all of us breathless and laughing as the dangerous-leopards-not-30-feet-from-us tension melted away.


We were so glad to be witness to such a rarely-seen event, and share the experience with Erin's family. Incredibly, I have now officially seen more leopards than I have seen cheetahs, servals, or caracals (other felids – cat species – commonly seen here in the Mara). I hope this leopard luck continues throughout the rest of my time here! Their spotted, whiskery faces and intense eyes have bewitched me; I cannot wait to see more!



Monday, January 18, 2016

Take the stage, cubs!

          Each morning at 0530 and every evening at 1700 we fisi campers venture out into the splendor that is the Masai Mara to conduct obs, or observation sessions, within our study territories. In a nutshell, we roam the grassy lands in search of hyenas for roughly three hours in order to collect different types of data. Half of an obs session is spent exploring the entire territory with the hopes of locating some of our study hyenas to see where they are, who they are with, and what they are doing, and the other half is spent at a communal den observing den-dwelling cubs, their mothers, and any other hyenas within the clan that are present at these social hotspots. 
          A communal den is where young cubs first begin to learn their ranks through early aggressive and submissive interactions beginning even before they emerge their natal dens, as well as through near constant socialization with other cubs, sub-adults, and adult mothers. When I say a communal den is a ‘social hotspot’ what I mean is that during these portions of an obs session you really get to observe the complexities of spotted hyena social structure by witnessing nursing aggressions, play behavior, interactions between pesky sub-adults and defensive mothers, less frequently seen hyenas who drop in to say hello and greet others, and immigrant males who remain at a distance or make their boldness known by approaching the dens. Side note: A greeting is a common interaction we observe between hyenas where two hyenas will each lift their legs and sniff the other’s genitalia in order to facilitate social associations and connections with other clan members. 
          Communal dens often consist of multiple den holes, which lead to complications when attempting to observe behavior. These dens are then referred to as den complexes, which consist of the multiple den holes and what we’ve dubbed in the field as the den’s ‘stage’. This is where we are able to most easily and clearly observe what is happening during a communal den session. Here in Talek West, our study hyenas experience near daily experiences with tourist vehicles and have overtime taken to denning deeper and deeper within dense shrubbery. As you can imagine, this makes observations challenging, as the hyenas will wander in and out of sight amongst the ever difficult to navigate orange-leaf croton bushes. As frustrating as this can be, the stage is where all the magic happens.
The stage of Resurrection Main Den with some of the cubs wandering and stand looking at the car. 
          As a thespian I’ve always appreciated the performing arts, so when I learned that the field researchers had colloquially been referring to spotted hyena behavior as a soap opera, I was eager to see why. Having subsequently learned that the den stage existed, I quickly learned why the stage was called that – oh, the hyena dramatics never cease. For me, it has been the cubs that have taken starring roles in these daily productions of the Talek West soap. In one of my former posts I blogged about the egg and milk trials I’d begun to conduct for one of our graduate students, Eli Strauss. Further investigating the process by which cubs learn their ranks, Eli is researching when and how young cubs do so through egg and milk trials provoking agonistic (aggressive and submissive) interactions. It has been quite the pleasure to take an active role in this data collection for Eli. 
Meet Hemingways.
Here he was one lucky cub, having a powdered milk source and trial all to himself - a solo, you could say.
          The stars of my trials have been one group of young cubs of the same cohort. A mix of high and low-rankers, these cubs have heightened my interest as I’ve conducted trials throughout the early months of their lives to nowadays as they each approach graduation age, which is when they will slowly begin to explore further and further away from the communal den with their mother, taking graduation walks and learning the ropes of surviving in the territory. Witnessing the development of their individuality has been an absolute dream as I’m personally consumed by ponderings of individual behavior within social populations. In particular, three pairs of litter mates have captivated my research interests, undoubtedly, but have also found a special place in my heart as I’ve watched them develop from tiny black cubs to now older cubs on the verge of graduating.
Catching some z's before a trial, it didn't take long after I deployed the egg source to arouse
Kerri Strug and Tamika Catchings from their ever-so-adorable lackadaisical state. 
          The ‘cast members’ of the trials (in order from highest to lowest ranking) are Joule (JOUL), Kilometer (KILO), Hilton (HITO), Hemingways (HEMI), Tamika Catchings (TAMI), and Kerri Strug (SRG). Each has displayed individual differences in behavior throughout the trials. JOUL, the now youngest daughter of the matriarch of the clan, Buenos Aires (BUAR), is not only the highest-ranking cub but is also the second highest-ranking hyena of the entire clan and she undeniably knows this is her place within the hierarchy. She is the scrappiest of the bunch, asserting her rank in every trial and making it known that she is not to be messed with, especially when it comes to the milk! 
Here we have Joule glaring at the car during a milk trial.
Shortly after this she aggresses on the two cubs beside her for a better feeding position. 
          Her subordinate littermate, KILO, has a bit of a different profile. He too, seemingly, knows where he stands in the clan, but spends more time by himself, wandering the perimeter of a trial watching the others battle it out for an eggshell or a lick of the powdered milk. Together though, the two of them are a forced to be reckoned with! They’ve asserted their rank through what are known as coalitions, aggressing together onto all of the other cubs, sub-adults, and even adult mothers through breathtaking duets of lunges, snaps, and bites. 
During an early morning egg trial, Kilometer seemed more content basking in the
sun's rays and watching the other cubs duke it out than taking part in the action.
          Next, HEMI and HITO are actually the niece and nephew of JOUL and KILO. These two stick together. They’re always joining and leaving a trial together, feeding together, and aggressing together through coalitions when necessary. A lover of eggs, HEMI doesn’t let another cub or even sub-adult near his egg during a trial. Being the smallest of the group, HEMI was formerly known as “tiny” before we knew who his mother was, and has never let his size get in the way. 
Hemingways is a bold little one, approaching our car close enough to reach out and touch him (which we don't do of course). This makes snapping irresistible head shots of him just too easy! What's not to love?
Hilton was in control of this egg trial, consuming nearly all of the egg source before the other cubs could snatch some. 
          Near the bottom of the clan, TAMI and SRG are actually the oldest of these cubs and seem to tolerate the aggressive behavior of their younger, significantly higher-ranking cub counterparts, to a certain degree of course. It seems they know their place is beneath the others but still successfully counterattack when they need to. Both feisty in their own right, they’ve seemed to be far more aggressive during milk trials and certainly defend themselves often. 
(Top: Tamika Catchings; Bottom: Kerri Strug)
 I often refer to these two as the ethereal and effervescent silver-haired duo.
We've been finding them wandering further and further from the den and always together.
They are the only hyenas I've seen with their coloration - true silvery beauties. 
          As the egg and milk trials ‘productions’ continue, it has been beyond entertaining and inspiring to witness these cubs’ behavior and I am constantly yearning to observe them. 
Here’s to you cubs, the stage is all yours! 
An unidentified black cub (meaning we don't know who her/his mother is) stand and looks at the car.
Perhaps we have some future 'talent' for more egg and milk trials? 
          Have any questions about cubs in particular, or about hyenas in general? How about a question you’ve been itching to ask about Kenya or the Mara? Post your question(s) below and I’ll make sure to respond to them as soon as possible. Asante sana and take care! 


-- Jared P. Grimmer --
All Photos Property of Jared P. Grimmer 

Sunday, January 17, 2016

I'm Back!



“I find myself driving along yet another rocky red dirt road. It is cold, dry and dusty, as it has been every morning. Despite this, I can still feel the pressure of the sun’s rays as they filter through the windshield and warm my soul. The horizon stretches so far that I can see the gentle curve of the earth’s surface, and the clouds seem fixed in the azure bowl of the sky, reminiscent of a Georgia O'Keeffe painting. I have lived in New Mexico all my life, and these images always connect me to the earth beneath me and sky above me, to my home. Only right here, right now, I’m somewhere else that feels like home, but isn't. The same sky, the same smell, even the dirt looks the same, but I’m not spooking black-tailed jackrabbits out from under junipers as I trundle along; no, instead that was a springhare fleeing into a copse of acacia bushes. That’s right, despite the odds I somehow managed to achieve my childhood dream to travel halfway around the world to a mysterious land to study the habits of foreign mammals. I’m in the Masai Mara Reserve, Kenya! However, I don’t feel as if I have left the only home I have ever known, I belong here. This savannah is as familiar to me as the vast mesas of the American southwest and many of the animals as well: the jackal, a coyote; the impala, a whitetail deer; the cape buffalo, a bison. Even the animal I am tracking right now has its own American counter-part; though physically different, both are wrongly reviled by many as villainous killers. It would only be natural for me to find parallels between my beloved wolves and Africa’s most successful predator, the spotted hyena.”

I wrote that statement during my first stint as a research assistant back in the spring of 2013, and I used it in my first grant application as a graduate student in the Holekamp lab later that fall. It’s been about two years since I have been separated from the Mara, my Fisi family, and of course my beloved hyenas. However, in those two years I have grown as a graduate student, and refined my research plan, all in the hope of returning to study the personality development of Kenya’s most amazing carnivore. Now I’m back and I still feel the same way I did three years ago. Kenya is my home away from home no matter how different it may appear.

“What am I doing out here?” Well, back in the lab I have been quantifying the social development of personality traits using the field notes RAs send home every quarter, while at the same time analyzing hyena gene expression and regulation using our lab’s archived blood samples. The goal of this study is to determine if an individual’s social development can affect how their genes are expressed later in life, and if this variation in gene expression matches the variation observed in personality traits of adult hyenas.  Using the field notes and the blood samples I have already found some interesting results suggesting that the level of submissive and aggressive interactions a cub experiences early in life is related to later adult aggressive and submissive personality traits.

However, now I need to spend some time with the little hyenas to determine if mom’s presence during early development is altering the cub’s social experiences, which will require me to follow moms and their cubs very closely. As such, I will be posting a lot of cute cub photos and behavior for the next couple of years for everyone to enjoy, such as these little guys below.



video



Until later, Safari Njema



Thursday, January 14, 2016

Who am I? Match the tracks with the correct animal.

Fisi camp needs your help!
Someone has been sneaking around camp waking 
everyone out  of their slumber.

We need to track them down. Luckily they have left their tracks behind.
Can you guess which tracks belong to who and track down the thief?
The evidence we have gathered is as follows:
1. Quiet and sneaky.
2. Makes an eerie howling sound.
3. Lives in the bushes and is most active at night.
4. Seems to love Bacon, Butternut squash and Potatoes.

Please help Fisi camp out.
Its up to you!


Who does these tracks belong to...

Fugitive number 1. 

 

The Dik Dik or the Thomson's Gazelle





Fugitive number 2.



Is it a Hippo, Elephant, or a Giraffe











Fugitive number 3.


Is it the Genet...
 or the Bush Baby





Fugitive number 4.

And Last but not least, 



Are these Wild dogs, Lion, Hyena or our pet local, feral dog, Crazy's tracks?







Cast your votes in a comment and find out the answer soon.






Tuesday, January 12, 2016

Back Home and Missing Camp Already!


This past year has been quite an adventure, and now that I’m home, it’s time to reflect. In camp I learned a lot, and not just about hyenas. From learning the basic mechanics of the camp vehicles, to off-road driving and learning to drive a stick, to maintaining the solar panels and wiring and much more, it certainly was an incredible experience. And, of course, I also learned quite a bit about hyenas!

But, I’ve written enough about all of that in my past blog posts. It’s time, now to say farewell. I’ve been home for a few weeks now, and I’m already missing these guys:






And I’ll miss all of my friends out in the Mara as well!

So, my time in the Mara is finished (for now), and it’s time for me to move on and finish my bachelors degree. I wish only the best to the project and everyone out in the field right now. I’ll always remember my year in the field fondly, and I can’t wait until I have the opportunity visit Kenya again.

Michigan State University | College of Natural Science