Introduction to Solomon Island Leaf Frogs

Solomon Island leaf frogs (SILF’s), Ceratobatrachus guentheri are endemic to the Solomon Island. Very little information and publications have been made on SILF’s since they were first discovered and described in 1884 by Boulenger (Strimple).

Characteristically, Solomon Island frogs display colors and patterning that strongly represents natural leaf litter; allowing them to remain well disguised in the wild. They have angular bodies and symmetrical folds of skin that run from the tip of their snouts, from their eye to their forearms, and down their dorsal to their vent. They often display bright yellow, tan, green, red, orange, brown, or rusty colorations that gradually develop into adulthood.

Another distinguishing trait of C. Guentheri is their “barks” or “calls.” People often associate the sounds of their calls with the bark of a small dog; like a chihuahua. Both males and females will call throughout the day with increasing intensity and frequency for periods of 5-15 seconds.

Adult C. Guentheri range in size up to 75mm snout-vent length for females and SVL of 86mm for males, weighing between 25-125 grams with the males being smaller and thinner (Strimple).

To this day, Solomon island leaf frogs are uncommon within the pet and reptile industry.

Environmental Needs of Solomon Island Leaf Frogs in Captivity

Solomon Island Leaf Froglet – Approx. 3 months old

Selecting the appropriately sized enclosure for a Solomon Island Leaf frog will be determined based on the life stage of the frog you are purchasing.

Juvenile Enclosure Size:

At Northern Gecko we recommend a 10-gallon glass or plastic enclosure for a juvenile leaf frog. We have had great success raising up individuals or groups of 3 young leaf frogs in a 15L Sterlite bin kept on paper towel with sphagnum moss on one side for a humid hiding area, a section of raised cork bark in on the opposite end, and a shallow 1.5oz water dish.

Adult Enclosure Size:

At Northern Gecko we keep our adult 1:1 breeder’s in a 24x18x18 Exo Terra terrarium. You can use a 40-gallon breeder or other long and low tanks for trios. We do not recommend vertical height for this species!  

We have a preference towards bioactive enclosures with adult C. Guentheri and have had a greater success of copulation in a naturalistic enclosure. We use Zilla Jungle mix for the substrate with an approximate depth of 2”, BesGrow sphagnum moss throughout the enclosure for a humid hide and egg depositing area, various sized NewCal cork bark and nut pods, a dug in ceramic water dish, live plants, and various leaf litters. Isopods are a great addition to this set-up as they naturally break down waste and keep the enclosure clean!

It is important to note that this species can become easily stressed in a glass tank. We suggest “blacking out” 3 out of the four sides of the tank, with the bottom 3” blacked out in the front. This creates a secure environment for your SILF, preventing nose rub or injury from jumping into the glass.

Many captive SILF’s may also lack the pronounced horns above their eyes due to excessive rubbing on décor. Elevating cork bark within the enclosure will prevent this.

Humidity:

We maintain a relative humidity of 50-80% within the environment by not adding additional air holes to the Sterlite bin and spraying the moss and top of the bin lid once a day in a juvenile set-up. For glass enclosures you can add cut acrylic sheets to the lid to reduce the speed in which humidity escapes the tank. You will need to experiment to determine how many times per day or week you will need to spray the enclosure to maintain this humidity range. Long periods of extremely low humidity can prove to be fatal. Placing a Zoo Med or Exo Terra hydro thermometer within the enclosure will allow you to accurately gauge the parameters within.

Temperature:

Temperature needs are an important factor when keeping frogs as they are highly temperature sensitive. SILF’s should be kept between 70-80f with preference towards the mid-70s. Temperatures below 70f and above 80f can be fatal to this species. Most households are kept steady in between this range; however, you may need an external heat source if the enclosure falls below the mid-70s. We recommend having an additional heat source on hand in the case of a sudden change in temperatures.  

An incandescent or plant light such as a SunBlaster tube light may produce enough heat to maintain an appropriate temperature within your enclosure. Remember to always use a thermo-hydrometer when testing new heat sources! External heat can cause humidity to drop faster than expected.

Feeding:

C. Guentheri use a “sit and watch” hunting method and prefer moving prey items. In the book, Advances in Herpetoculture, the original group of frogs at the woodland park zoo were maintained on newborn geckos and skinks! Today, captive SILF’s diet consists mainly of crickets dusted with Repashy Calcium Plus and Vitamin A Plus vitamin and mineral supplements. Juveniles are fed 3-5 ¼” crickets daily and adults are fed 3-5 1” crickets 3 times a week. Increase or decrease feedings based on your individual frogs needs.

Sexing:

C. Guentheri are not easily sexable at a young age and often take 10 months to a year before they can be accurately sexed. The presence of mating calls is not an accurate measure of sex as young males can begin calling within the first 4.5 months and females can also be heard calling back. Males have a few distinguishable features from females. Males have two parallel white structures that run down their under belly. In the book, Advances of Herpetoculture, they suggest that these visible structures are the ureters in males and are hidden by the reproductive organs in females.

Breeding Solomon Island Leaf Frogs and Raising Froglets

We have successfully bred Solomon island leaf frogs without the use of a rain chamber which is predominately necessary for successful amplexus in frogs. However, you will have greater success stimulating breeding with a controlled MistKing system that mists the enclosure for periods of 15-30 minutes long. You will need an appropriate drainage system in place.

This species uses a unique reproductive strategy. Males will dig a nesting hole within the dirt and begin calling the females throughout the day and night during the “rainy season”. Following amplexus the male will not be found near the female and the female will now be in the hole he created! After, the female will fill in the nesting hole following oviposition and will usually be found away from the nesting site but close by. They can hide their nesting sites extremely well. Checking the enclosure every 3 weeks will ensure you don’t miss a clutch of eggs.

Unlike other frog species, SILF’s lay eggs; there is no tadpole stage. The average clutch is 15-30 eggs with multiple clutches per year given a “rainy season.” We recommend removing the eggs carefully from the nesting site after oviposition.

You can incubate the eggs on a vermiculite substrate in an 8oz container with one hole for air flow and a lid. Place the eggs facing the direction you found them in small divots within the vermiculite, only covering the lower half of the egg. Placing moist sphagnum moss on top of the eggs has proved to be successful for us. Incubation temperatures should be between 70-75f, with an average incubation period of 30 days. It is important that the moss on top of the eggs stay moist but not wet during the incubation period.

Rearing Froglets:

Once the froglets have hatched after the incubation period you will need to transfer them carefully into a 48oz deli container using gloves to avoid contact with the oils on your skin. Keeping the environment simple and clean with the froglets is important during the early stages of life. We raise groups of 10-15 froglets in a 48oz container on paper towel with some sphagnum moss off to one side and a shallow water dish that is changed daily. Humidity and abundance of food is extremely important to reduce the mortality of froglets.

Froglets should not be offered food until after the first week of life or longer as they need time to fully absorb their yolk sack. They will not eat during this time. After 1.5-2 weeks you can start introducing small items of prey such as springtails and wingless fruit flies dusted with Repashy Calcium Plus. Froglets should be offered food daily once they begin eating to avoid cannibalism. Slowly introduce pinhead crickets into their diet after the first month.

Froglets should not be sold until they are at least 4 months of age and readily eating crickets.

Strimple, Peter D. Advances in Herpetoculture. International Herpetological Symposium, Inc., 1996.