The end of the summer has been very busy at the Smithsonian Conservation Biology Institute, because we have two new members in our Persian onager herd! We are excited that our second and third foals have arrived and did not have any complications during parturition (birth). Both the foals were born Aug. 25. Dorri’s filly (girl) was born early in the morning before we arrived at the barn, and Farah’s colt (boy) was born around 11 a.m. Both are doing great! All three of our mares, Dorri, Farah and Sayeh, were maiden mares, or first-time moms, and we are relieved that the birthing process went smoothly for them.
In the beginning, both Farah and Dorri were very protective of their little ones and made sure that the other herd members didn’t get too close. That is normal behavior for new onager moms, but they soon became more comfortable with their foals spending time with other members of the herd.
Although the mares were very round at the end of their pregnancies, they were back to their pre-pregnancy weights soon after giving birth. Part of that weight loss is from the foal itself. Having a gestation period of a full year means that foals weigh approximately 50 pounds at birth. They waste no time in learning to nurse and usually start quickly after birth.
Producing milk requires a lot of energy and calories from the mares, but it gets the foals the nutrients they need to grow. It does not take long for the foals to double their weight, and they continually grow for the first few years of their life. On average, onagers weigh about 510 pounds. So, the foals have a long way to go until they have matured.
At first, we didn’t see much interaction between the foals. That is mostly because mares are fiercely protective of their foals. They are not willing to let anyone get close — even other foals in the herd. As the foals start moving around on their own, that changes, and their moms are forced to let them explore and move further than just a few feet from their sides.
Now, all three foals are starting to interact and play with each other, which is very fun to see. Their mothers are still trying to be protective, but the foals can just gallop away if they would rather play than heed their moms’ protective instincts.
The foals’ personalities are starting to emerge as they become more coordinated and confident. We have noticed that their personalities and tendencies are already being shaped by their moms' personalities. Farah is very independent, and she has passed that down to her colt. He is the troublemaker of the bunch, even though he is the youngest. He will run at the other foals to make them scatter and then run back to his mom for safety from any disgruntled or startled herd members.
His rambunctious behavior is directed at Farah as well as the other foals. He runs in front of Farah and tries to kick her. Although it may seem unusual, rough play is not uncommon for this species, and we expect to see foals kick and tussle from time to time.
Dorri’s filly is more aloof and is not extremely interested in the keepers. She and Dorri keep to themselves in the pasture. Despite being the oldest of the youngsters, Sayeh’s colt is timid. He is closely attached to his mom and doesn’t stray far away from her.
As all the foals grow, we’ll get to know them as well as we know their moms.