SLOW PROGRESS WITH BREEDING DENDROBATES HISTRIONICUS.
About three years ago I managed to purchase a pair of D. histrionicus, much to the envy of many.  These are a dark red/brown base colour with small intense orange/red spots covering the whole body.  It is not a large frog, being approximately the same size as D. auratus.  I have found them to be quite a hardy frog, able to take a wide range of temperatures and humidity but have found the preferred temperature to be between 18°C and 23°C with humidity above 60%.  It is impossible to tell the two sexes apart as their toe pads are the same size and they have identical builds.  The male's superb call, like a duck quacking, is the only give away.
For the first eighteen months of owning them they showed no real sign of mating al though the male did call on a regular basis.
After about two years clutches of eight to ten eggs started to appear on bromeliad leaves though there was either a very small amount or no jelly covering them which resulted in them drying out within a couple of days.  This continued for about another six months with no viable tadpoles.
After persuading my girlfriend to let me build a shed in the garden, I am now the proud owner of a fourteen-foot (4.5m) log cabin, which houses my frog and gecko collection and the D. histrionicus are now settled into a more permanent enclosure.
This naturalistic setup with large bromeliads and an orchid is a sliding front glass tank 36"xl5"xl2" (950 x 400 x 300mm).  The substrate is Hortag covered by orchid bark and a little peat.  There are also some rocks covered in moss that I have obtained from my place of work and which grows in cool temperatures 
The frogs are fed Drosophila and micro-crickets, along with small insects that come out of the moss.  There are a number of laying sites, consisting of, bromeliads, coconut huts and film canisters, all of which have been used for depositing clutches.  The tank is sprayed heavily around 4.30pm Monday to Sunday and at also at about 11.30am Friday to Sunday.
Over the last six months I have been able to control the environmental conditions much better and they are now producing more viable eggs, with clutch sizes increasing to around sixteen, although only twelve may be fertile.  The eggs are small and dark grey, almost black.  These have been developing and turning into tadpoles, but they are not going full term.  They die before they break out of the jelly.  It seems that the frogs are doing something right as progress is being made, but it is slow.
I would like to know if anyone else has seen this before in D. histrionicus or any other Dendrobatid, and if so have they solved the problem?
News Flash
Shortly after finishing this article, a clutch of 16 eggs deposited under a coconut hut has produced 2 free-swimming tadpoles in a Petri dish.  The parents did not take any interest in them at first so I placed a couple of D. imitator intermedius eggs next to them as a food but without success.  I came home from work a few days later to find a pair of food eggs deposited in the Petri dish with them.  I will keep you in formed of any further developments.  If you have any advice please contact me at samgeckosarah@hotmail.com
Sam Hawkins
North Somerset