Lemurs - the Next Generation

Less than a month old, Pia's infant, Conrad, has a face that already hints at the handsome sifaka he will become.
Photos by David Haring

Duke Lemur Center is happy to present the tiny Coquerel's sifaka above. He is Pia's third offspring and Trajan's 40th grandchild.(See previous blog post.) This fine, young male was just named Conrad for Conrad II, Holy Roman Emperor and descendant of Charlemagne. The name presages the magnificent creature Conrad will become.

Pia, Conrad's mom

When it comes to parenting, Pia is one of the best. That has been a boon to this wee one, who was born with a low birth weight. Added to the low birth weight, mom had trouble producing milk for her baby, so the Primate Technicians stepped in to help - feeding Conrad six times per day to supplement mom's milk. Pia is being given medication to stimulate milk production and to assure her health and recovery from giving birth. While the Lemur Center prefers to allow the mom to care for her offspring naturally, we step in when needed to assure the best situation for the lemurs.

Pia has been very attentive to her new son. She grooms him, helps with his toileting, keeps him warm, and protects and cuddles him. The Primate Technicians and the Lemur Center veterinary staff have been very attentive to both Pia and Conrad - helping Pia recover from the rigors of birthing, helping her stimulate milk production, and making sure both mom and son could thrive.

It is paying off! Pia is regaining her vigor and now producing milk, and her son is gaining weight, eating hungrily, and beginning to jump and play like the healthy young sifaka he is becoming. Soon Pia and Conrad will rejoin their sifaka social group, and the new young male will be able to play with his two siblings.

Pia - with Conrad's older brother

Pia - with Conrad's older sister

You can schedule a tour to visit the lemurs by calling 919.489.3364. Come see us!

Trajan - last of the wild-caughts

Trajan, a much loved Coquerel's sifaka

The Duke Lemur Center lost another venerable founder last week, when Trajan, a Coquerel's sifaka imported from Madagascar in 1984 and estimated to be 29 years old (quite elderly for a sifaka,) passed away. Trajan was the last surviving wild-caught Coquerel's sifaka from a group of 11 (5 males and 6 females) imported from Madagascar on three dates: 1982, 1984, and 1986. The Coquerel's sifaka importation was a great success story, and the contribution these wild-caught animals have made to the captive gene pool (along with Nigel, a captive-born animal) account for the total of today's captive population of 44 animals residing at the Lemur Center and at six American zoos.

Trajan and Cornelia

Trajan made more than his fair contribution to the captive gene pool, siring 18 offspring (8 of which are still living) with three different mates (Cornelia, Marcella, and Paulina,) 40 grandchildren (20 of which are still living) and two great grand offspring. Hence, 28 of the 44 living Coquerel's sifaka in captivity are closely related to Trajan! On the day that Trajan died, his daughter, Pia, gave birth to grandchild number 40.
Along with being one of the most prolific lemurs in Lemur Center history, Trajan led one of the most interesting lives. He and his mate Cornelia, were the first sifakas introduced into a Natural Habitat Enclosure (NHE) when they were released into NHE1 in July 1986. The pair lived in NHE 1 & 3 for much of the following nine years and produced nine offspring before Cornelia's death in May 1995.

In July 1991, Trajan became desperately ill and nearly died. The veterinary staff worked tirelessly to save him, and when he recovered the vets wrote, "Trajan has recovered from his illness, but blood work shows his liver to be in terrible shape. Because of his weak nature (probably due to old age,) he will be kept inside and not returned to a natural habitat enclosure." But Trajan did recover fully, and his obvious health convinced the vets to change their minds. He had returned to the forest of NHE3 within a year, continuing to spend most summers free ranging for the next thirteen years!
After Cornelia's death in the spring of 1995, Trajan was introduced to a new mate, Marcella and her young son, Nero, in NHE 6 in August of 1995. Marcella and Trajan had four offspring and spent their summers in NHE 6 until he was removed from Marcella's group in 1999 and introduced to Paulina and her offspring (Antonia, Phillip, and Zeno) in September of 2000. Paulina and Trajan had five offspring and lived together (spending summers in NHE 3) until August of 2004, when Paulina was sent to the Sacramento Zoo. It was during this period that Trajan demonstrated that he was not only capable of siring offspring, but that he was good at caring for them too, a somewhat unusual trait for a sifaka male.

Coquerel's sifaka infants are born in mid winter, and by the time Paulina/Trajan's group was moved from their winter cages to the forests of the natural habitat enclosure, the youngsters would be anywhere from four to six months old, well on their way towards weaning and independence. However, a largely independent five-month-old infant, when introduced to a new environment (such as a forested enclosure) generally becomes somewhat anxious and wants to return to the security of his/her mother. So suddenly, the juveniles will jump on Mom's back and want to be transported everywhere, when they are actually capable of getting around under their own power (sort of like teenagers.)

Trajan and offspring

Hence, when Trajan and Paulina's group were introduced into the forest in the springtime, there inevitably would be a youngster who suddenly wanted to start riding his/her mom's back again. But Paulina, not the most patient of mothers, would have none of it, and would nip at the juvenile until he/she jumped off. The juvenile would then, of course, be terrified, clinging petrified and stranded on a tree in this unknown forest, while the group, led by Paulina, moved off. Every year, however, the gentle Trajan would come to the stranded juvenile's rescue and allow him/her to ride his back for the entire day until the group was back inside for the night. The whole scenario was repeated the next day and the next for a week or two. I will never forget the sight of the 20-something Trajan patiently carrying a juvenile at least half his weight, making jumps and climbing trees as the group moved through the woods.

Trajan was wonderful with his own offspring and with females and very young male offspring of other males, but once unrelated offspring in his group got to be a certain age, Trajan would not so gently "encourage" them to seek new territory. During his life, he forcibly ejected Nero and Zeno from his new family groups at a much younger age than they would normally be ejected. After all, he was no saint, and this is standard male sifaka protocol.

Alas, this macho male sifaka attitude towards other males finally caught up with Trajan when in August of 2008, his four-year-old son, Maximus, attacked him, severing his Achilles tendon. Trajan was helpless under this assault (not only was he a frail almost 30-year-old, he had also long since lost most of his teeth.) Although the staff of the DLC quickly came to his rescue, it was the beginning of the end for Trajan. He spent his final days housed alone - but never lacking for human company and admiration.

Post and photos by David Haring

Lemurs at Duke Lemur Center enjoy a bit of mid-winter outdoor ranging

Sifaka in Winter at Duke Lemur Center
Photos by David Haring

This week is freezing cold in Durham, with lows in the teens and highs only reaching in upper 30s. But last week was unseasonably warm, with temperatures as high as the mid 70s, and several groups of lemurs were released from their barns into the freedom of the Natural Habitat Enclosures (NHE). One of them was the NHE 3 Coquerel’s sifaka group, which, at six members, is one of the largest sifaka groups we have ever had here. Not that they will be this large for much longer, the adult male, Jovian, showed some aggressive impatience with his two juvenile sons, Theodosius (5 years old) and Marcus (4 years old) last summer, and although the group is now back together, mom (Drusilla) is pregnant again, and after she gives birth, Jovian might very well give both his boys the boot.

Nonetheless last week, all tensions were forgotten, and the whole group was foraging and traveling together through the forest when I went out to visit with them. But something about the whole scene was out of whack, the group just didn’t look as at home as they usually do in the forest, and then I realized what was missing from the scene: leaves! Sifakas are highly folivorous primates, and a group in a winter bare NC forest look odd and lost and out of context, sort of like a polar bear on a sandy NC beach might, or a lion on an iceberg. Steve Coombs was watching the group the next day, and was also struck by the oddness of the sifakas in the winter forest, but his comment was that they looked very small amidst the winter trees, much more so than they would in a forest in mid summer.

Airborn sifaka
Photo by David Haring

However, it is great to see free ranging lemurs of any type, especially sifakas, leaping through the forest on a December’s day. I don’t think sifakas have ever free ranged as late as December. When we first released sifakas into the free range enclosures, in the mid 90s, they were not locked into their barns several times a week, as they are now in order to train them for the times they need to be caught. Instead the sifakas were fed at stations scattered throughout the forest, and they might not be caught, or enter a barn, for the entire summer.

When it was deemed too cold for the animals to be free ranging (late October or early November), a technician would go out into the forest with a tempting food tray, and when an animal buried hid head inside the bowl to feast, the technician would hand grab it, and then carry it to a kennel for later transport into the building. This tended to be a fairly stressful maneuver, both for the technicians and the animals, as a missed grab meant that the animal would free range another day, and might have to stay outside in uncomfortably cool weather. Luckily in those days the free ranging groups consisted mostly of pairs with only an occasional juvenile offspring. We have certainly come a long way since in the management of free ranging groups of animals!

Despite the rather odd appearance of the free ranging sifaka group, however, I have no doubt that they were delighted to be away from their stuffy barn and into the open forest where they could leap between trees and climb up to the top of a 60 foot pine, and do all sorts of things that you just cant do when you are in a cage. Except eat leaves. In fact, the only leaves in sight for the animals to munch on were a few pitiful looking honeysuckle leaves, and the sifakas were gobbling them as quickly as they could. However when the technicians came in late in the afternoon carrying the group’s ration of sumac leaves (thawed from one of the six chest freezers packed to the hilt with prime sumac this past summer by David Brewer), there was no question that they would trade their bare forest freedom for the taste of a succulent leaf, and into the barns they went!
Post by David Haring

Greetings from the DLC Research Department

The force with which it's limbs strike the ground are measured as an aye-aye runs across a pressure plate. (Photo by David Haring)

It seems that we in the research department are a bit behind the times in blog world, as I see that the education and conservation departments are already up and running, illuminating their forks of our trifocal mission at the Duke Lemur Center. We will not be left behind, I say! And so, I would like to introduce Research at the Duke Lemur Center. I am often asked why we do research on these animals and what types of research we do. First things first, which means addressing the first question of why we do research on lemurs. How will that help their plight in the wild and their survival in captivity.

The use of captive animals for scientific research ultimately helps conservation efforts of wild populations in a number of ways. It stands to reason that the more we can learn about endangered species, the better our chances of conserving them. By studying the biology of these animals in areas such as behavior, reproduction, morphology, physiology, ontogeny, and genetics in a controlled environment, we can better define species and subspecies status, better quantify their ecological requirements, better understand their interactions with other species, and better determine a conservation plan given the animals and environment we have to work with. In addition, we do a number of research projects that focus on animal husbandry and care so that we can keep our animals happy and healthy here in Durham.

A thermographic image of an aye-aye eating an egg shows temperature variation. Look at his hot ears! (Photo by Andrew Cunningham.)

The Duke Lemur Center houses the largest and most diverse captive prosimian colony in the world, and these animals are used by investigators both at Duke and other national and international academic institutions for both species-specific and comparative research. Only non-invasive research is allowed at our facility, and all projects must be approved by both the DLC Research Committee and the Duke University Institutional Animal Care and Use Committee (IACUC), both of which contain veterinary oversight, before any research can begin. By maintaining these animals at the Duke Lemur Center and allowing experts in the US and international scientific communities to carry out studies of the animals in our colony, we take an important step toward the long-term goal of lemur conservation. Stay tuned for descriptions of the projects we are working on here at the DLC!

A researcher observes a ring-tailed lemur. A ring-tailed lemur observes a researcher. (Photo by David Haring)

Lemur Learning: Training Enriches Exam Time at Duke

Life is fairly quiet at the Duke Lemur Center at this time of year. The Duke students, who would normally be conducting observations or doing non-invasive research, are preparing for or taking exams. The more than 30 Duke affiliated researchers (All our research is non-invasive) are preparing or grading exams. So from the lemurs' point of view, there are not only fewer people, there is less activity than usual.

Now, lemurs and their fellow prosimian primates, lorises and galagos, are intelligent. In fact, research being done here is showing that they are more intelligent and more socially oriented than was previously understood. That means they can get bored. So, 365 days of the year our dedicated Primate Technicians make certain that their lemurs' lives are interesting.

One way the technicians enrich the lemurs' lives is through a training program. First, all the techs completed a course by Meg Dye in animal training based on the science of operant conditioning . They use positive reinforcement to train the lemurs to allow themselves to be touched by the trainer, to sit on a scale, to enter a kennel, to move to a certain certain spot - a set of behaviors that just seem like play to the lemurs, but can serve a purpose when needed.

For instance, Pia, a Coquerel's sifaka, is very pregnant. So her technician, Sam, is training Pia to allow Sam to touch her belly. That way Pia will be less stressed and more comfortable after her infant has arrived and Sam needs to approach Pia and lift the infant from her stomach to be weighed. Sam will give a familiar command and Pia will know that it is safe for Sam to touch her belly and that she will receive a tasty treat.

Each appropriate response from the lemurs merits a treat, like a raisin or a nut - depending on what is a treat to that animal. The techs wear a special belt that has a treat pouch attached. When the animal responds appropriately, the techs click a clicker. That sound tells the lemurs that a treat is coming. That way if there needs to be a brief wait between the behavior and the reward, the lemur still knows it's coming. I think of it as that space between the timer dinging on my stove at home and a warm cookie making into its way into my mouth.

The techs also make sure that they end each session with behaviors that are sure to get a positive response from the animal. That always brings the Jackpot - a small handful of treats.

As I watched the training, it certainly looked like both trainers and lemurs were happily engaged. I know as Sarah and David were training sifaka in one cage, the ringed-tails in the next cage were getting as close to the sifaka cage as they could, jumping excitedly and making a sound that Sarah described as a whine. It was easy to picture a young child watching another play with a special adult and calling, "My turn! My turn!"

Weekends at Duke Lemur Center

You might wonder what it is like for the lemurs at Duke Lemur Center over the weekends. Do they get lonely? No. Tours are available on Saturdays. You can schedule one by calling 919.489.3364.

Also the Primate Technicians are here every day. They arrive before dawn and spend their days caring for these endearing animals. If the nights are unusually cold, someone is here around the clock making sure the colony of prosimian primates is comfortable and safe. They know these animals well. They know if someone is being picked on by their fellow lemurs. They know who has a good appetite, and who might seem a bit listless today. If anything seems amiss, the techs alert our veterinary staff. Our vets know more about lemur medicine than anyone in the world.

Our scientists are the top of their fields, too. Our director is Dr. Anne Yoder. She is an Evolutionary Biologist. Dr. Yoder is pictured above with a Sifaka. If you want to know more about Dr. Yoder and Evolutionary Biology, click here.

If you would like to support the work done at the Duke Lemur Center, click here.