BREEDING REPORT

Andy Gibbs
Last update: 17 August, 2002

D. ventrimaculatus is a small frog, reaching a maximum size of about 20mm (snout to vent length). There are several variants or colour forms described for this species, and it is likely that these may be reclassified as separate species on the basis of geographical distribution, colour and pattern and even vocalisation. Variations of this species are found from Peru, through Brazil to the Guianas. The ‘form’ that I acquired has a metallic golden body with irregular black stripes, a blue/green mottled belly (hence the scientific name) and a yellow chin spot. I was able to compare some of these with the French Guiana form, which was available at the Spring Frog Day at Maarn in 1995. The French Guiana form appeared to be more yellow and less metallic and with less black coloration, although I suspect this may be due to the frogs I acquired being later generations of captive bred stock compared to the F₁ generations which I was assured were the French Guiana form. As I couldn’t afford them I assume they are still in Holland.

My frogs were placed in a terrarium, which contained a small group of D. auratus. The terrarium was heavily planted with Ficus pumila, which completely covered the rear wall and an assortment of other plants was already in residence. Pieces of cork bark have been secured to the rear wall and two coconut shell breeding sites provided. There were no bromeliads in the tank.

I had placed the frogs in the tank in the spring of 1995. They were a group of four, which happily appeared to be two males and two females. The males appeared to be sub adults when acquired, although the females were mature, having been purchased separately on an earlier occasion.

In November 1995 I observed one of the males calling for the first time. He was sitting on top of a coconut shell and his throat pouch was distended. The call was a very low chirruping, not unlike a cricket call.

In the last week of December I found the first clutch of eggs, laid in one of the Petri dishes underneath the coconut shells. Thereafter, eggs were laid regularly, with clutches varying from eight to thirteen eggs. The later clutches tended to have a greater proportion of fertile eggs. No clutches were found after mid-March; prior to that they averaged one each week.

The tadpoles emerged from the jelly after a period of some two and one half to three and one half weeks. In view of cannibalism, I decided that they should be raised individually. They tend to be very small, but develop gradually. I found that a varied diet of dried fish eggs, Daphnia and powdered bloodworm in conjunction with flake fish food was accepted, although I feel that some investigation into dietary needs of this species may be fruitful. The tadpoles appear to be slow developers, as I wrote in October, and I still have tadpoles approaching metamorphosis from eggs laid in March.

A significant percentage of froglets that emerged (approximately twenty to thirty percent) had spindle leg and did not survive. I believe that this may reflect Nature. I had a discussion with Clive Osborne, who has actually observed the species in the wild and he described the tadpoles in a water-filled hollow in a tree voraciously feeding on their weaker brethren, and even on weaker froglets struggling to leave the water. Thus it would appear that our artificial propagation techniques enable the survival of weaker specimens that would not survive in the wild.

I have distributed some of the offspring to members of the group, and some of you have described mating and egg-laying by frogs in bromeliad vases. This more natural egg-laying may well see fewer, but fitter, froglets.