By Carrie Flood
Baby giraffe Siku is more than a pretty face.
Siku, our newest baby giraffe, is undeniably adorable. She ranks a solid 11/10 on the cute scale. As much as you may enjoy coming to see her on the Savanna or seeing her picture on our social media, you can’t imagine how much we swoon over her. We are just as in love as you are, but Siku is so much more than just a gangly assemblage of spots bumbling about the Savanna; she is an important part of a much larger plan.
There was a time when giraffes in zoos weren’t identified by species or sub-species; they were tall, spotty camels and that was that. Just as zoos began to shift away from the menageries of old and into the conservation focused institutions of today, biologists were beginning to recognize the significance of genetic variations. Genetics has come a long way, but it’s still not perfectly understood; biologists still disagree about the definition of “subspecies” and where to draw the lines between similar populations. Meanwhile, we must make decisions based on the most current understanding.
The AZA (Association of Zoos & Aquariums) is an organization that sets national standards of care, facilitates cooperation and shares knowledge across institutions. Within the AZA is a collaboration of people who compile genetic data of all the animals in a managed population and make recommendations to individual zoos about who should breed with whom and where they should do that. This collaboration generally includes people from at least some of the following: the PMC (Population Management Center), the SSP (Species Survival Plan) Coordinator, the studbook keeper, a professional Population Advisor and sometimes others. The idea is to maintain a healthy managed population in zoos as a safeguard in case their wild counterparts disappear. (This strategy has worked before. See: black footed ferret, Arabian oryx, California condor and a whole host of others!)
A comprehensive genetic inventory of all the giraffes in zoos revealed that while North America had a robust population of pure Masai giraffes, the reticulated population was more “mutt-like.” European zoos had the opposite; a healthy reticulated population and a mix of the Masai sub-species. It was decided that North American zoos would be asked to focus on maintaining a healthy Masai population and let Europe focus on the reticulated giraffes. The goal is to get a population of 150 genetically diverse Masai giraffes in AZA institutions. (As of March 2018, there are 123.) When making recommendations the PMC must also consider the logistics of moving such animals and the age of the individual. See, female giraffes tend to lose fertility if they don’t have a calf in the first few years of their reproductive cycle, so if you have a female who is genetically “valuable,” the window for her to reproduce closes as she gets older. It’s a thing.
The Phoenix Zoo has the Savanna, which is a large habitat and ideal for a breeding herd of giraffe. We had a group of reticulated giraffes but began the transition to Masai based on the recommendations. Sunshine, a lovely young Masai giraffe, arrived a few years ago from the Santa Barbara Zoo, and immediately took a shine to our handsome male, Miguu. Just 15 months later, (be thankful you’re not a giraffe, ladies,) we have Siku. And even as she explores the world and learns how to use all her lanky bits, teams of smart people are planning her future; she has a very important role to play in securing the future of her species.
Siku represents the work of hundreds of people, decades of data collection, genetic analysis, mind boggling algorithms and the hopes of another 100 years of healthy genetics for the managed population of Masai giraffes.
And you thought she was just cute.