Keepers Play Matchmaker for Masters of Disguise
At the Reptile Discovery Center, keepers play matchmaker to true masters of disguise: Henkel’s leaf-tailed geckos! These bizarre-looking lizards may have evolved to blend in to bark and lichen, but there’s no hiding the team’s breeding success: they welcomed 5 hatchlings this year. Leap into the world of this secretive species with keeper Sara Hasenstab.
What sets this species of gecko apart from the others?
Not only does the Henkel’s leaf-tailed gecko’s tail look like a leaf, but the rest of their body is bordered by textured skin flaps that obscure the outline of their body when flattened against bark. They are truly masters of camouflage—their highly variable patterns perfectly mimic different types of bark and lichen! Leaf-tailed geckos are some of the most beautiful lizards on the planet and are a wonderful example of nature's variability.
This species also has the "sticky" toe pads that most geckos are famous for, comprised of folds with millions of microscopic “hairs” called setae. These specialized toes allow them to climb on smooth surfaces, while their tiny claws help them stay agile when moving through the trees.
How did you “matchmake” the hatchling’s parents?
All of our adults are between 3 and 4 years old—prime reproductive age—and came to us from the Riverbanks Zoo in South Carolina. Prior to their arrival here, we received a recommendation to breed them from the Species Survival Program (SSP). It’s very exciting that they successfully reproduced, as we have now added more genetically valuable individuals to the population in human care.
The mother laid her first egg at the beginning of January 2020 and the last one at the end of March. There were seven total, and she laid each about three weeks apart. Usually they lay two eggs per clutch, but this particular female only laid one egg at a time.
Other than finding the right spot to lay her eggs, there is no parental care in this species. We separated the eggs from the adults during incubation so there was no confusion over what was or was not a snack when they hatched. She buried each egg overnight in the moss on the bottom of her habitat. Keepers removed the eggs and placed them in containers of damp vermiculite, which mimicked the temperature and humidity of that area.
How many leaf-tailed geckos hatched?
Only five out of the seven eggs were fertile, but all five of them hatched! The first hatchling emerged from its shell April 29, and the last hatched Aug. 30. At the time of their hatching, they measured two to three inches in length (including the tail) and weighed about 2 grams. To put that in perspective: adults can grow up to 11 inches in length, and their mother weighs about 70 grams.
What do the hatchlings eat? How do they hunt?
When they first hatch, Henkel’s leaf-tailed geckos have some built-in energy reserves from their yolk sac. In the first 24 to 48 hours, they shed off their newborn skin—and that becomes their first meal. We then start offering them small live crickets to hunt. One way that we know they are eating on their own is by tracking their defecation. Once they get the hang of hunting, they grow surprisingly fast!
These geckos are nocturnal and hunt mostly at night. Their specialized eyes give them incredible night vision which helps them find small invertebrates in the trees. There is evidence that nocturnal geckos can see up to 350 times better than humans in dim light, and may even see color at night!
If they are active at night, then how do they spend their day?
They spend the day sleeping! It's pretty amazing how light levels affect their activity level. Before we turn the lights on in the morning, they are up and about exploring their habitat. As soon as the lights turn on, they find a good place to flatten out (usually the wall of their enclosure, or a smooth branch) and spend the rest of the day doing their best bark impersonation.
Got any tips for spotting them?
Luckily, they love to sit on smooth surfaces and most days rest on the exhibit glass. It's perfect for seeing the toe pads and skin fringes up close!
How can we help Henkel’s leaf-tailed geckos in the wild?
As with all leaf-tailed geckos, they are endemic to the islands of Madagascar, which is known for being a biodiversity hotspot—80 to 90% of its animal and plant species are exclusive to the area. The biggest threat has been the continuous deforestation happening throughout Madagascar, which is aggravated by climate change. As with all island species, once the habitat disappears, there's nowhere for them to go.
Luckily, there are steps we can take here in the United States to protect this species. First, be a responsible consumer! Reduce and recycle single-use items, and try to purchase locally sourced goods and sustainable materials whenever possible. You can also support Madagascar conservation groups. Whether the groups work to protect lemurs or geckos, these animals all share the same forests.
Our planet's biodiversity is more impressive than we may ever truly know. We each need to do our part in our day to day lives to reduce our impact on these fragile ecosystems, which can be hard in a modern, convenience-driven world. I'm starting by planting more native flowers for pollinators and supporting my local farmer's market.
Last but not least, support accredited zoos! We are working hard to conduct research, save species and educate the next generation of wildlife conservationists. We can only do that with your help!
This story appears in the November 2020 issue of National Zoo News. Planning a visit to the Zoo? Please note that the Reptile Discovery Center is temporarily closed to help prevent the spread of COVID-19.
UPDATE: Please note that the Zoo is temporarily closed as a public health precaution to help prevent the spread of COVID-19.