Updates From the Zoo's Lion Keepers
August 25
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| This image was captured late last night on the internal camera we're using to monitor her. |
Today Shera reached the 104th day of gestation, and we’re excited to say that tomorrow she will officially be within the time period (105-115 days) that we expect her to give birth. She continues to have a good appetite, and based on her behavior, we are not expecting her to give birth tonight.
Yesterday Naba and Shera started spending the night apart with access to visit at a howdy door. Shera promptly fell asleep after coming inside and finishing her food, and it appears as though Naba slept outside Shera’s door, where she could keep an eye on her younger sister.
Today was the first day that Shera was separated from Luke. Instead of sharing the lion yard with Luke, Shera and Naba spent the early part of the day in one of the yards where visitors typically visit the tigers. Both girls appeared to welcome the change in scenery. Stay tuned for more updates!
August 18
What to Expect When You’re Expecting… Lion Cub Addition
Determining Pregnancy in Lions
Down at the lower end of the Zoo we are making final preparations for the impending birth of lion cubs. Shera bred with Luke during the second week of May, and Naba bred with Luke during the first week of June.
Without performing ultrasound, there is no test that can determine, with 100-percent accuracy, whether or not the lionesses are pregnant. Year round, we collect fecal samples from the lions, from which hormone levels are analyzed to provide reproductive information. When a lioness breeds, her hormones should rise. If she is going through a “pseudo pregnancy” then the hormones will drop down to a normal level about 48 to 55 days after breeding. If hormone levels remain high for longer than this period then it is highly probable that she is pregnant. The gestation period for lions ranges from 105 to 115 days.
As of today, Shera is 97 days into her gestation period and Naba is 76 days into hers. Their hormone levels have remained elevated so it is very likely that they are both pregnant. Additionally, each of our females have put on about 40 pounds since breeding with Luke and are exhibiting mammary development.
Preparations
So far, all of the lions are continuing to go outside together for the day. Naba and Shera have started spending nights together in their cubbing dens. They have the ability to visit Luke overnight through a howdy door, if they choose to, by traveling through a chute that leads to his enclosure. Their behaviors and interactions are being closely monitored and will be the best guide for making management decisions regarding separations and daily yard access. In a couple of days, Shera and Naba will be separated from Luke. Additionally, Shera and Naba will be gradually separated, although they will have the ability to visit each other through a howdy door. Once birth appears to be imminent, Shera will be given privacy in the comfort of her own cubbing dens, although she will continue to be given the option to visit with Naba at the howdy door.
A few weeks later, Naba will be due. During the time between the births of Shera's and Naba's cubs, the decision of whether or not to give Naba access with Luke again will largely be based on each lion's behaviors. Some possible behaviors may include Naba showing a disinterest in shifting outside without Shera, or Naba may act anxious to go outside with Luke. We also need to take Shera’s behaviors into consideration. She may be stressed without her sister close by, or she may show a preference to be alone with her cubs.
With one week left until our cub watch begins for Shera, we are also adding bedding to the girls’ dens. Since the unfortunate death of Naba's cub, we've investigated various alternative bedding options. We still believe the use of bedding is imperative. Most of our criteria for bedding remain the same: shavings to quickly absorb urine, covered in soft hay (no straw), which serves as a sort of cohesive blanket over the shavings (which could otherwise separate easily to expose the floor beneath), protecting the cubs from trauma during the fragile first weeks of their lives. Additionally, we sought out hay with as few seeds as possible.
Pre-parturition Behaviors
When birth is imminent, we will expect to see a decrease in appetite, an increase in grooming behaviors, and significant restlessness. It will look as though the lioness can’t quite get comfortable by standing up, lying down, pacing, adjusting the bedding, and turning from side to side while lying down. By the end of this week, we will offer extra meat in the mornings to gauge each of the female’s appetites, and monitor them closely using cameras and microphones inside of the cubbing dens.
Pre-birth Excitement
As the caretakers for the lions, we are experiencing a wide range of feelings. More than anything we feel focused and prepared. Having combined our institutional experience and knowledge with information received from other institutions, in preparation for Naba’s first cub, we have a solid plan and feel as prepared as we can be. From here on out, most decisions will be driven by the lions’ behaviors.
One of the jitters we are feeling is for Shera, our first-time mother. The first critical hurdle once parturition (labor) begins is the successful delivery of cub(s), followed by Shera’s response to her cub(s). Our hope is that Shera’s maternal instincts will kick in quickly, although there is always a possibility that she could reject her cubs, or even do harm to them. We will only interfere and consider hand-rearing under very extreme circumstances.
At the same time, we are really excited about the prospect of watching Naba and Shera raise their cubs together, and learning the role Luke will take in it all. Lions cubs are some of the cutest babies within the animal kingdom. Adding to this excitement are some of the things we don’t know, such as how many cubs each lioness will have. The common range is one to four cubs each!
We will keep the updates coming so be sure to check back frequently!
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