Breeder’s Spotlight: Breeding Fire Skinks – March 2013

 

By Jennifer Greene

Breeding the Fire Skink

Step one:  Breeding

In writing this article, I will be making the basic assumption that you, the fire skink keeper, are already familiar with the care and husbandry of successfully maintaining your fire skinks.  Breeding is the natural next step in husbandry once you have successfully established your pair or group of skinks.  Sexing Fire Skinks is at best an exercise in educated guesswork, especially if you have young or lean skinks.  Most skinks available at pet stores are not old enough or established enough to develop the very subtle characteristics that allow for an attempt to be made at sexing them.  For this reason, I highly recommend feeding your skinks well for at least a month before attempting to guess at the gender of your pets, as all fire skinks generally look like females when they are first acquired.  Females are slightly more slender in the head and body than males, and lack in anything resembling hemipenal bulges.   Males have a slightly broader head and are built a little more “beefy” than females of a similar size and age, and develop very slight jowls with age.  When mature, breeding adults are compared side by side, a careful eye can distinguish the genders, but even an experienced keeper can find it difficult to accurately sex fire skinks.

On the left, you can see the female, while on the right is the male skink.

Feeding your skinks well will result in a healthy, robust pair that breed easily and often.  My adults feed on large crickets, superworms, giant mealworms, dubia roaches, hissing cockroaches, and pinky mice once the female has laid eggs.  They also eat canned insects with gusto, with canned caterpillars being a particular favorite of my pair.  I emphasize again that a good diet is a major part of successfully breeding your skinks and getting multiple, fertile clutches.  Healthy, well fed skinks can and will lay between 3 and 5 clutches of eggs a year without any problems whatsoever.  However, a malnourished or underfed skink may experience egg binding, parasite blooms, or crash from lack of calcium or other nutrients used to make her eggs.

This male Fire Skink does not look markedly different from the female – but he does exhibit great body condition!

Alright, so your skinks are eating a varied diet and are as fat and chunky as the ones you see pictured here.  Great!  They will take care of the rest.  You may not see actual copulation, but it will take place without any encouragement from you as long as temperatures are warm enough.  Fire skinks tend to breed whenever ambient temperatures stay above 75, and daylight hours last longer than 12 hours.  This means their breeding season starts in the early spring, and can last until mid-autumn.   Females are capable of retaining sperm, although they do not seem to lay more than one clutch when they do so.

Step Two: The Gravid Female

Once your skinks are breeding, and your female is starting to look even plumper than before, it’s time to make sure you are diligent about keeping up on a nice, varied diet and providing her with adequate supplementation.  Your female skink may appreciate a slightly warmer basking area if yours is typically only about 85 to 90 degrees.  When my skinks are breeding, I offer them a basking zone with the warmest area reaching temperatures of about 95 degrees.  The female will seek out the warmer temperatures to grow and develop the eggs within her, and this also helps to ensure her appetite stays up – she’ll need lots of food to grow all the eggs she’ll be laying!

Fortunately for the fire skink keeper, care for gravid females is not much more difficult or different than for non-gravid females.  More care needs to be given to ensuring that she is eating a rich diet that is well supplemented, but for the most part she will take care of her needs on her own.

This female is most likely gravid, but it can be hard to tell!

Part Three: Egg Deposition and Incubation

After about 30 days, the female will look fat enough to burst, and at this point her appetite is likely to be next to nothing.  She’ll start digging and exploring throughout her cage for a suitable place to lay her eggs, and it’s at this time that you need to pay close attention to the cage to make sure you catch when she lays her eggs.  You’re extremely unlikely to actually see her laying the eggs, as they are very secretive about it, but you should be able to notice when she has suddenly lost a significant amount of weight.

Once you notice that the female seems to have abruptly lost half her body weight, carefully dig through the cage to find the eggs.  They have excellent taste in nesting sites, and will select a nice moist (but not wet) area to lay their eggs in.  Most often, mine laid their eggs under their water bowl or under cork rounds on the humid side of the cage.

Clutches range in size from 3 to 6 eggs on average, with clutches of up to 9 eggs not being uncommon.  If you maintain your cage well with bioactive substrate (see The Art of Snake Keeping for information about bioactive substrates), you can actually leave the eggs in the cage until they hatch.  I did this the first time entirely by accident, not realizing my skinks had already begun laying eggs – the first set of babies were a very pleasant surprise!  Adults can and will cannibalize the offspring, so do not leave them in the cage once they hatch.

To incubate your eggs in a somewhat more professional manner, remove them carefully from the substrate once you have found them.  Marking a dot on them with a permanent marker can help you ensure you keep them oriented upright in the position they were laid.  From there, place them in your preferred incubation medium.  I use Hatchrite, as it’s a nice, clean looking material that holds moisture well, comes pre-mixed, and I’ve had good success with it.  I keep my clutches in the incubator in 4.5” deli cups with lids, and write the date I found the clutch on the lid.  Bury them about halfway into the incubation material, and then leave them for as long as it takes to hatch!

When incubated at 84 degrees, most clutches hatch at 55 to 65 days after being laid.  I leave the babies in the cup until they’ve all hatched.  While I have not seen a study on fire skinks in particular, I know for other species of lizards it has been shown that the activity of the first babies to hatch climbing over the eggs of their unhatched siblings encourages the babies still within their eggs to hatch.  It does not hurt them to remain in the incubation cup for a day or two while their siblings hatch, so leave them in the cup and let them do their thing!

Part Four: Caring for Neonates

Set up the new hatchlings in a cage similar to the adults, just on a smaller scale.  My adults are in a 36” x 18” x 24” terrarium, and I raise babies in a 36” x 12” x 12” terrarium.  I provide my babies with a 100 watt powersun to bask under, which results in healthy, fast growing and chunky little babies.  Humidity is important for babies, and I highly recommend providing them with a thick layer of substrate you can easily add moisture to.  I often pour water directly into the substrate, especially directly under the heat light, to ensure that the babies are able to burrow at the moisture level they prefer.

Diet for babies is simple to start with, as there are not many prey items small enough for hatchling fire skinks.  Small crickets 1/8” of an inch to ¼” of an inch are small enough for them, and once they are a couple weeks old they are usually big enough to start eating regular sized mealworms as well.  Waxworms can also be added to their diet, which can help keep them full if you notice your babies are nipping at each other’s tails.  Hungry babies will consume the tails of their clutchmates, and the easiest way to prevent tail nipping is to simply keep them fed!  I always leave a dish of regular mealworms out for my hatchlings, and offer 5 to 10 small crickets per baby every other day.  On this regime, your hatchlings will be large enough to go to a new home within the first month!

 

Captive Husbandry of the Fire Skink – January 2013

By Jennifer Greene

Fire skinks, or Riopa fernandi, are arguably some of the cutest lizards out there.  With big, doe-like eyes set on a cute little face, bright colors and little legs on a long body, they are capable of making even non-reptile lovers squeal about how cute they are.  Their common name arises from the vivid red coloration on their sides, which connects to red strips down the side of their neck and up into bright red cheeks.  They typically have a black base color with a white checkered chin, and their backs are often a golden tan, with some individuals having a redder color instead.  They are on the smaller end in size, with mature adults reaching between 14 and 20” depending on tail length.   Their relatively small adult size compared to other pet lizards, in combination with their adorable faces and ease of care, make them quite delightful pets to keep.  Captive bred skinks can be downright outgoing, often coming out to see their owners and check for more food.  As rewarding as these little skinks can be, they are not often kept, or not kept for extended periods of time.  They are seen as either too difficult for the beginner (not the case!) or too basic for the more experienced keeper.  My hope is to help the beginner embrace these adorable creatures, and to highlight the rewards of keeping them to encourage more herpers to give them a shot.

Fire skinks can regrow their tail, much like this captive bred baby is doing!

Most fire skinks available to reptile keepers today are wild caught in origin, with most originating from a handful of countries in West Africa, often the same countries that baby ball pythons come from.  A small number of keepers have successfully bred their fire skinks (myself included), so captive bred babies can be available on occasion – it just takes patience sometimes to find them.  Wild caught skinks are not usually difficult to get acclimated to captivity, especially when set up properly and given time to settle in.  Captive bred babies do tend to be more outgoing than their wild caught cousins, but regardless of your skink’s origins, their care is the same.

I prefer to keep them in a relatively large cage, as they can be extremely active and will utilize all the space.  You can maintain one or two in a cage as small as a 20 long, but I highly recommend a cage at least 36” x 16” x 16”.  I keep my adult pair in an ExoTerra terrarium that measures 36” long by 24” tall by 18” deep, and I routinely see them using the entire cage.  In a cage like the ExoTerra one that I use, you can offer them a nice thick layer of substrate to burrow into, which they will love.  I use a combination of cypress mulch, Eco Earth, and orchid bark to achieve a nice, natural looking appearance that maintains humidity well and does not require frequent changing of the substrate.  I check the cage daily for feces, and once a week stir up the bedding and add fresh water to keep it moist.

I rarely actually see my skinks in their water bowl, but I do find fresh feces in the bowl about every other day.  Because they are prone to pooping in their water dish, I prefer to offer them a bowl big enough for them to climb into, and for mine I use a ZooMed Large Corner Dish.  I furnish their cage with a variety of items for them to climb on and around, and they really seem to love clambering up inside of cork tubes to bask under the lights.  I have a large tube on each side of the cage, and a few large and medium pieces of cork flats piled throughout their cage.  In addition, I added some fake vines to provide some foliage in the cage and visual barriers for them.  Using fake or live foliage helps make the cage look a little nicer, and provides cover for your skinks to hide behind and feel safe within their cage.  You may even see them peeking out at you from under the leaves!

One of the most important things about skink housing is something that doesn’t even get placed directly in the cage, but instead over the top: lighting!  As terrestrial skinks, these little critters don’t require exceptionally intense heat or light, but they do need heat and UVB provided during the day.  In the large cage that I use, a 100 watt powersun bulb provides all the basking light and UVB, and to illuminate the rest of the cage I use the new ExoTerra Ion bulbs.  I really like using the Powersun bulb on larger cages to provide heat and UVB, as the skinks really seem to thrive with the ability to get close to the light as needed.  The new ExoTerra Ion bulbs are nice, extremely bright bulbs that do not put out measurable amounts of UVB, making them ideal for illuminating reptile cages that already have a source of UVB.  Putting too many UVB lights on one cage has the potential to irritate the eyes of yourreptiles, and does not give them the option to escape UVB exposure if they feel the need to.  The Ion bulbs are super bright, and that in combination with their low cost makes them ideal for illuminating just about any cage you have.

 

My favorite bulb for most diurnal reptiles – the fantastic Powersun!

Basking temperatures can reach up to 95 degrees Fahrenheit as long as the cool side remains below 80 degrees.  How you achieve these temperatures is up to you; I use only the Powersun bulb in my cage during the day, and at night my skinks have a 75 watt infrared bulb to keep cage temperatures from dropping too low.  Exactly what wattages you use for your own cage at home is something you may need to tinker with to get it just right.  A warmer home (75 to 80 degrees) will not require as hot of a basking light, nor would it need a night time heat source.  A cooler home (65 to 70 degrees) would probably require higher wattage bulbs.  Using a thermostat or rheostat to help monitor temperatures within the range you prefer can make your life much simpler, rather than switching out multiple wattages depending on the time of year.  I also use a Zilla Power Center Digital Timer, which makes my life immensely easier because it switches all my lights on and off on its own.  All the lights are automated, which just leaves the daily maintenance to cleaning out the water and feeding my skinks!

Feeding your skinks can be one of the most enjoyable aspects of their care – they are often very enthusiastic feeders, and readily consume most live feeder insects.  The staple of the diet can consist of primarily crickets and mealworms, with full grown adult skinks easily consuming 1” crickets, giant mealworms, or superworms.  In addition, I highly recommend including roaches in your skink’s diet.  Mine happily eat dubia and hissing cockroaches, and I do not doubt that they will consume just about any species you can order online or find at your nearest reptile expo. Waxworms, reptiworms, silkworms, and hornworms all can and should be added to your skink’s diet whenever possible, as the variety in their diet will help your skinks grow and thrive their best.  On top of all that, they will often also eat canned insects, such as canned caterpillars, grasshoppers, and even snails, so there is no excuse for not providing a varied diet for your lizards!

Adult Skinks can easily eat superworms

Waxworms are good treats to feed occasionally too

Illustrating the size difference between regular mealworms and giants – both are acceptable food items!

Whenever offering live insects, it is also important to dust them with a high quality reptile calcium and/or multivitamin.  I use and highly recommend either the ZooMed Reptivite (with D3 for lizards kept indoors), or the Repashy Calcium Plus, as both have a great balance of calcium, multivitamins and vitamin D3.  While you may be making quite the effort to provide your skinks with as varied a diet as possible, it does not come close to approaching the dozens or hundreds of different insects and small animals they would consume in the wild.  For this reason, it is important to dust your skinks’ food at least every other feeding, or as per the instructions on your calcium or multivitamin supplement.

When it comes to handling your skinks, it really depends on your skink and how well it reacts to your presence.  This is where it can pay off to pick up a captive bred baby, as they are often already well-accustomed to human interaction and handling.  Certain long term captive skinks mind it less than others as well, and even originally skittish skinks can become habituated to their owners with time.  The key is patience and time: feeding your skinks well and letting them get used to you for several weeks or months will give them time to settle in and learn that you are not going to harm them.  Once they are well established and feeding well for you, you can attempt to coax them out or handle them for short periods of time.  Not all skinks enjoy handling, especially at first, and they can be extremely squirmy and fast, so you may want a spotter around for the first few handling sessions in case your skink escapes!  Most skinks are perfectly happy if they are rarely, if ever, handled, so do not feel as though you need to handle your skinks for them to do well.  If anything, they would probably love to be left alone entirely, and instead will come out to check out their surroundings and watch what is happening outside their cage.

Any of these supplements are suitable for your skinks!

Calm, confident handling is key to teaching your skink to accepting human interaction!

Fire Skinks are cute, brilliantly colored little lizards that can be incredible pets for the keeper looking for a smaller species of lizard to display in their home.  Their sturdiness and ease of care coupled with how frankly adorable they are makes it hard not to love them as a fantastic beginner lizard or fun side project for the experienced keeper.  Breeding them is also fairly easy and straightforward, and once established they can be extremely prolific.  Check back with us next month to see a Breeding Spotlight take you through step by step on how to condition, breed, incubate, and raise Fire Skinks of your own!