Derek Petrie
(Membership
Sec. Carnivorous
Plant
Soc. U.K.)
Last update: 17 February 2000
In May this year I flew to Atlanta, Georgia to attend the first international meeting of the International Carnivorous Plant Society. The meeting was hosted by the Atlanta Botanical Garden. During the evening buffet reception, the subject of frogs - and in particular Dendrobates - came up. Strange thing how many carnivorous plant growers are also frog keepers! It turned out that Ron Gagliardo, who is the curator of the tropical plant house, is also a keeper and breeder of Dendrobates. Ron keeps and breeds the frogs in the public lobby of the Dorothy Chapman Fuqua Conservatory. This is a 16,000 square foot glass and concrete building housing the tropical and desert plant collections. In the lobby there are two all glass vivaria, three feet long by two feet deep by one and a half foot wide. Each one houses four different species of Dendrobates and is set out in the same manner. The layout consists of the tank on a wooden cabinet containing a filter, which comprises a small glass tank containing filter media i.e. filter wool and foam. Those of you familiar with marine aquarium trickle filters will understand what I mean. From this filter a small pump (called a power head) returns the system's water to the terrarium. The terrarium base is lined with under-gravel filter plates, which are covered with compost that consists of a mixture of chipped bark, perlag and peat. In fact this is old, used Nepenthes (tropical pitcher plants) compost. The depth of this layer is about six inches. At one end of the terrarium is a mound of rocks rising about ten inches. This consists of reddish volcanic lava, the surface of which is highly porous and so soon develops a lush matt of mosses and algae as the returning water from the filter flows down its surface. |
Due to the nature of the compost and the flow rate of the water, the drain-age rate is very slow and so pools of open water several inches deep form in depressions in the compost. It is in these pools that you can see several tadpoles freely swimming. The terraria are densely planted with a wide variety of tropical plants (more on this subject in a future article) and topped by a tank hood containing a mixture of very powerful fluorescent and mercury vapour lamps. Again those of you who have seen the lighting over a tropical marine reef tank will get the idea of just how bright these lights are! The frogs (including D. auratus, leucomelas, tinctorius, tricolor and azureus) are all highly visible and active. Visibility is aided by the fact that the terraria are glass all the way round i.e. there is no background. What struck me the most was that the frogs are very contented (the tadpoles being proof of this) despite having all-round illumination, extremely bright overhead lighting and being in a very busy public area with people using flash guns and tapping on the glass.
I hope to be able to get a fully detailed account of frogs at Atlanta by Ron himself for a future article. I am intending to prepare a series of articles on plants in frog terraria/vivaria, including a discussion on lighting requirements. I would like very much to hear from other people of their own plant-growing experiences and of any thoughts they might have on lighting, with regard to both frogs and plants.