Awakenings

This is my favorite time of year in the reptile department of my zoo. Spring is here, and that means one thing. When I come in on Wednesdays, I’m often greeted by sights like this:

(click on them to enlarge)

There are four babies hatching here. See them?

How about now?

 

In this box, we have two different subspecies of Madagascan spider tortoise; Pyxis arachnoides arachnoides and Pyxis arachnoides brygooi. I can tell the difference from here. I’ll show you how.

P.a. brygooi like to burrow. They hatch, they burrow. P. a. arachnoides hang around on top of the substrate.

These babies are all genetically pretty valuable, as both species are critically endangered in their native Madagascar. Any successful hatching is significant, but sometimes some offspring are even more valuable to the program.

There’s someone I want to you meet, but allow me just a moment to tell you its story. When animals are taken out of the wild and reproduce, that next generation of offspring is known as F1. It’s not unusual for animals to reproduce in captivity after being removed from the wild. Tortoises, rhinos, cheetah, elephants. The real trick is in getting an F2, that next generation, one that is truly captive bred. F1 and F2. Sounds like a series of astromech droids, doesn’t it?

Now allow me to introduce you to our very first F2 Common Spider Tortoise.

Sleeping in its egg.

A couple of days later, it emerged completely after having absorbed the last remaining bit of yolk. And lest we forget the gratuitous belly button shot:

It may take a few weeks for its umbilicus to disappear completely. Currently there are tiny wrinkles around its belly button where it is closing up.

 

It’s roughly the size of a quarter, the very first offspring of both parents. There are very few, if any, other F2 of this type anywhere in the world. I am so proud of my zoo and their dedicated staff for what they have done to perpetuate this species! Well done, Michael!

Playing Favorites

I admit it. I know I’m not supposed to, but of all the little ones, I have a favorite. Don’t tell the others, please.

Astrochelys radiata, the radiated tortoise

I know that all the babies are adorable, but this one has a special place in my heart. The population of the radiated tortoise (Astrochelys radiata) has dropped by half in the last ten years. They have been wiped out of most of their range, so captive breeding programs are of critical importance. She’s the second one my zoo has hatched.

I call this one “she” because she was incubated as a female. Many reptiles have what is called temperature dependent sex determination. When the egg is first laid, the embryo within has no gender at all. The temperature at which it is incubated has an impact on whether they develop into boys or girls. Keepers can often produce the gender they need by altering the temperature at which they incubate the eggs. With this species of tortoise, higher temperatures usually yield more females. Lower temperatures tend to create males.

A perfectly proportioned tortoise in a tiny package

Here she is with her older sibling who was hatched in July. I have no idea whether the older one is male or female. Its egg incubated outdoors for a bit, so it was subject to unknown temperatures. Radiographs in a few years can tell if we’ve got a boy or a girl.

Pesky little sister

One thing I really enjoy about this baby is her personality. She is all go. I have no good recent pictures of her because she won’t sit still. From a biological standpoint, her curiosity isn’t a good thing because she might get eaten, but in captivity, it’s positively delightful.

I’ll be back on Monday full of my tales of adventure. And hopefully with some new pictures. Have a great weekend!