Cubs, Moms, and Fur

An obs session that starts with two little black figures poking out from the den usually means new cubs spotted in the Talek West clan! With new cubs come new tasks for the researchers here at Fisi camp. Not only do we have to identify the mother of the cubs; we also are presented with the task of aging them. The pattern and visibility of spots on a hyena is not only helpful when it comes to identifying an individual but it’s also a great tool for estimating age. With each new cub comes a puzzle, and as researchers we must put the pieces together in order to solve the mysteries of motherhood and age.

Determining the mother of a cub can be a more tedious process than one would think. Since we do not observe the adult females giving birth we use the act of nursing as a “maternity test”. When we see a cub nursing from a female, we can usually conclude that that female is the mother. Although there have been instances of a cub nursing from two different females it has not been observed very often.  This situation however can make this process even more daunting. When a cub is first seen above ground we aim to see the cub nursing a couple of times from the same female to have some certainty of the identity of the mother.

Now onto the subject of aging, when hyenas are first born they are all black and no spots are visible. The age at which we first see a new hyena cub however ranges. Some adult females, especially those who are lower ranking will not bring their cubs to the communal den until they are a couple of months old. The features of a hyena’s fur change significantly within the first few months. In order to age cubs we use a few key characteristics found on their bodies.

Here are a few stages:

A cub that is all black and seen above ground near the den can be 3 to 4 weeks old.

In the next stage, the cubs begin to develop white rings around their eyes, which eventually leads to the development of white eyebrows and faces. The white rings begin to appear at about 4 to 5 weeks old and white eyebrows and faces at 5-6 weeks.

Another section of the body that we use to denote age is the shoulder. Spots begin to emerge on the shoulders at 3- 3 ½ months. The white face is also still present at this stage.

As the hyena cub gets older more spots begin to appear. Instead of just seeing spots on the shoulder there are also spots along its sides and back. The legs of the cubs however may remain black. The fur is also short. If a cub has these characteristics it would be put in the age range of 4-7 months.

At around 8-9 months, the cub’s fur becomes fluffy and long also known as den graduation fur.  The cub begins to molt (the transition from short fur to long fluffy fur). These are some of the last characteristics we use to determine age.  

After determining what stage the hyena is in, we count backwards to determine its birthdate. For example, if it was December 10th and we saw a hyena for the first time with a white face and spots on the shoulder we would count back three months and give it a birthday of October 10^th.  Age is not only important in determining the birthdate of a hyena but it also gives us clues as to when a hyena should be graduating the den, dispersing, or having a litter of their own. While new cubs at the den create a new mystery for the researchers solve it also brings excitement and cuteness to the den.

Try and age the hyenas below! Come back to the blog for my next post to see if your estimates were correct.

Less than glorious introduction of a grad student who finally escaped the lab

Hello all,

My name is Sarah, and I’m a graduate student who will be in the field this summer and fall. I am usually in the lab working with all the lovely poop and blood samples that come from the hyenas out here in the Masaai Mara, but I have escaped the flourescent lighting and pipettes to spend some quality time with my study animals! 

My research focuses on the biological basis of individual and sex differences in aggressive behavior. (In other words: what is going on in your body that makes you want to fight your friends and family to the death for that last cupcake...or last piece of wildebeest flesh, if you’re a hyena?  And why might one sex resolve the situation with some well placed glares while the other draws blood?) You might already know female hyenas are more aggressive than male hyenas, which is unusual for mammals. We also see a wide variation in aggressive behavior between individual hyenas, with some generally being brattier than others. I’m trying to understand which processes in the body and brain cause some individuals to be more aggressive than others.

(Eg. What is going on in this girl's brain that makes her such a punk??? Photo by Kate Shaw)

       As hyenas get older, their social rank (which is inherited from mom) primarily determines how much aggression they exhibit. Low ranking animals risk injury if they attack a higher ranking animal because other hyenas will side with the higher ranking hyena in the dispute. 

(Two higher ranking hyenas gang up against a bigger, but subordinate hyena. Photo by Kate Shaw)

I want to measure aggression before the hyenas know any better, so I will be observing cubs that haven’t learned their ranks completely. This way I’ll be looking at behavior that is reflective of biological (ie. innate/natural) differences in aggressiveness and competitive ability. Later, I can go back to the lab and measure chemicals (such as hormones like testosterone) in their blood and poop to see if it correlates to their aggression levels.

(Cub fights are exciting because they show how aggressive cubs are before their rank influences their behavior too much. Photo by Kate Shaw)

While I’m in Kenya, I will set up situations in which the cub’s competitive sides can shine. This should be easy. All I have to do is present them with something they find tasty. Then, I sit back and watch adorable hyena cubs tussle over the treat.

Disclaimer: The sort of fighting we’ll see with the cubs is normal, and most of the aggression consists of threats (like a human glare) and chasing. The worst thing that happens is a cub gets scared enough that it will stop trying to get powdered milk. They won’t be competing more than they would normally. They’ll just be competing in front of me!

The set up for my experiment is as follows:

Step 1: Turn cubs into snack junkies

This one was easy. Cubs looooove powdered milk, so I’ve been merrily dumping it out of the car at dens where they can lick it up to their heart’s content. We want every animal to recognize and be excited about the powdered milk, so when we start the real science, they all want to fight over some milk.

(Cub with powdered milk)

(Cubs waiting for delicious milk to start falling out of the car)

Step 2: Find a good situation for the experiment

I’m going to need multiple cubs present to fight over the milk, and none of their mothers. A cub might be braver and more aggressive if they know their mamma is there to back them up.

Seems simple enough right?

Nope! This is usually what I find when I go to dens in search of motherless cubs:

Nothing..

Or everyone’s mom is here (the big furry blobs are moms)...

(So cute...so unhelpful)

Curse hyenas and their excellent mothering skills!

But still, with enough patience we finally found the perfect situation - lots of cubs hanging around the communal den without a mamma in sight! Perfection.

So, onto step 3.

Step 3: Put out the milk near the den.

Here I put the milk in an area the size of a medium suitcase. This is a small enough area that an ambitious cub will think it’s possible to hog all the milk, but large enough to make guarding the food a very difficult task. I can then watch the fights that ensue between the little junkies and test how well they compete for a valued resource.

Success! (The powdered milk is in the white stuff in the front center.)

Step 4: Sit back and watch the cubs compete over the milk

So now its simple, right? I put out the milk powder, it’s a great situation, and I have a bunch of little junkies. Well, apparently not because I sat at the den for 2 hours watching cubs run in and out of the den hole, romp around with each other and nap, and not ONE of them noticed the milk powder which was RIGHT IN FRONT OF THEM.

Sigh.

(Get your act together and find the milk, you darn cub)

In the words of my surprisingly-wise-at-times older sister (also a scientist), “If it was supposed to work the first time, they wouldn’t call it REsearch. They would call it search.” With that comforting thought in mind, I will keep toting powdered milk around in the hope that the hyenas start to feel more accommodating.

In the meantime, I had lots of time to take absurdly cute photos of the little punks ignoring the milk. Enjoy! 

P.S. Since I wrote this out, I've gotten a couple trials. Yay! Soon I will tell you all about it.)

A shy, long-eared cat

The most exciting animal sightings for us are not usually the ones that have tourists jumping up and down. Given that we study hyenas that might seem kind of obvious! But also, living here allows us, or at least has allowed me, to look beyond the large, majestic animals to the smaller, shyer, or rarer ones. I now always get really excited when we see rare animals such as unusual birds or shy, small mammals. Most of these animals I did not know even existed until a few months ago.

Recently, I had my best serval sighting yet. Servals are medium sized, spotted cats with large ears. They use their ears to pick up sounds made by birds, rodents, and other potential prey. Servals can even hear noises made by their prey underground! Their long legs help them reach deep into holes and pull out their prey. At the same time, servals can jump high into the air and bat down birds!

The serval we saw was walking along a track in one of the marshy areas of our North territory. She or he was very calm and just let us follow her along the track for a few minutes. She paused for a bit and drank from a puddle before moving off into the tall grass and out of sight. I always feel so privileged to have such wonderful sightings of these more unusual or shyer animals.

Run with your inner spotted hyena spirit!

Hello! My name is Hadley, I have been an RA in the Talek camp for the past year. Back in October, the hyenas inspired me to write this message to wish my college cross country team luck before their conference championship meet:

Jambo Team!!

As runners, you’ve probably heard and/or seen inspirations for racing drawn from cheetahs or lions, drawing on the speed and strength of these well known charismatic mega fauna.

This is not going to be one of those inspirations. As cross country runners, you hardly want to arouse the speed of a cheetah…we all know that insane sprints at the beginning of a race does not bode well for the other 5-7km. You also don’t really want to evoke the lion because…well…you can do better. Lions and cheetahs are what are called ambush hunters…they lie and wait, and wait, and then burst, pounce, and kill with a mighty bite to the neck. Coach would never approve of waiting, and the pounce/kill bite just might get you disqualified.  

Who you want to channel for Conferences tomorrow is...can you guess where I’m going ; )…the SPOTTED HYENA! Since Walt Disney didn’t do this magnificent creature any favors, please let me share why racing like a hyena is your best animal strategy.

Hyenas are what are called endurance hunters – they chase. A spotted hyena can lope tirelessly for miles upon miles, can hit top speeds of 60kph, and can pursue prey for several kilometers at close to that top speed (50kph). Most animals are unsuspecting of the hyena’s speed and especially their endurance, falling prey to the hyena’s prowess through sheer exhaustion. Hyenas can hunt alone, even taking down a bull wildebeest, but also can hunt cooperatively in packs and will do so to ‘circumvent the determined defense of herds/families’.

Are you seeing why channeling the spotted hyena will be your greatest advantage tomorrow? Not wasting time with waiting, not putting full energy into one burst, (not using a kill bite…) but rather calling forth endurance, bursts of high speed, determination, the element of surprise, and strength when alone but far greater when as a group.

Coach has told us all to “Be an eagle!” and to “Fear the Gopher”. Tomorrow, be that eagle, strike fear in the other teams as the Gophers you are….and channel your Spotted hyena spirit for the calculated, passionate, grueling and rewarding race you’ve all worked so hard for.

Whooping (the infamous Spotted hyena vocalization) for you from Kenya,

Hadley