Nicodemus Wilderness Project -- Global Registry of Apprentice Ecologists

Mantellas are a genus of neo-tropical frogs native to Madagascar. Historically they have been exported in large numbers relative to their fragile status in the wild, and although many of the species are classified as endangered, they receive minimal global attention as a species in need. The Malagasy government currently has no conservation plans for any species in the genus, and many species do not live within protected areas which make them extremely vulnerable to habitat destruction. Due to the threatened status of Mantellas in the wild and their rarity among captive bred collections, there is enormous potential for data collection and experimentation, as many of these species have not been extensively studied in captivity. The benefit of breeding these endangered frogs in captivity, has a couple purposes as applied to conservation. It is unrealistic at this point in time, to breed the frogs with the hope of eventually releasing them back into the wild, as the current situation in Madagascar is less than ideal, and the bio-hazards of this form of in situ conservation are serious. By breeding frogs in captivity, it reduces the stress on wild populations, and by having prices which compete with the price of imported wild caught frogs, people are less likely to support a trade which harms wild populations.

Currently no official preservation attempts are dedicated to Mantella crocea (endangered, population trend decreasing), although there is speculation (but no observed occurrences) that a population is present in Parc National de Mantadia. The lack of concerted conservation efforts dedicated to this species makes it a target for captive breeding efforts. Fortunately, the Convention on International Trade in Endangered Species (CITES) is only allowing 500 of these frogs to be exported from Madagascar in 2010. The estimated extended occurrence (range) is around 5,000 km2, but the area of occupancy is estimated to be less than 500 km2 total. Due to their sporadic but dense local populations, they are subject to exploitation even though such a comparatively small number are approved for export. By exploitation I do not mean that more than 500 individuals will be collected, but exploitation in the sense that the population may not be able to maintain itself even if only 500 individuals are collected.

Currently I have a group of 2.2.1 (Males. Females. Unknown) Mantella crocea, which have laid three clutches of eggs since I have obtained them this June. It is common among many amphibian species, to have the first clutch or two go bad, either because the frogs have not finished developing, or because the eggs are not properly fertilized by a male. The first two clutches laid were infertile and decomposed within a week of being laid, but on their third attempt about half of the eggs were fertilized by a male, resulting in over twenty developing eggs. The developing tadpoles quickly hatched out and were raised aquatically until metamorphosis. Over the past five years, there has been one recorded case of successful breeding with Mantella crocea in the states, so having twenty plus CB frogs available marks a significant point in their captive history. However, with many Mantella species there is the possibility of spontaneous fatalities, so even with seemingly healthy tadpoles there are no guarantees. Instances of Spindly Leg Syndrome (SLS) are extremely high in Mantella species- it is a fatal syndrome with unknown causes which manifests itself in deformations of the arms. The arms develop but are not strong enough to be used as support, and affected frogs die within days of morphing into froglets, either of suffocation or starvation. Fortunately, while the exact causes are unknown, there are many suspected causes, mostly having to do with nutrition (of both the parent frogs and the tadpoles) and water quality. I supplement the adults with over five supplements in attempts to provide the frogs with the correct types and ratioâ€™s of nutrients, and feed a varied diet consisting of Drosophila hydei, Drosophila melanogaster, crickets, termites, orange isopods, various species of springtails, bean beetles, grindal worms, mites, as well as sporadic field sweepings. This, in combination with cycled water, a varied tadpole diet, and the use of aquatic plants to improve water quality, has worked in preventing my Mantella crocea tadpoles from developing SLS. Currently ten frogs have morphed out and are eating springtails, with more on their way. My goal with the offspring is to have them registered within a program called the Amphibian Steward Network (ASN). The primary objective of the ASN is to track and manage amphibians using the International Species Information System (ISIS). By pairing my offspring with future imports or frogs currently in the states, genetic diversity can be enhanced and the integrity of the line can be strengthened.

Going forward, it is my hope and intent to bring my Mantella crocea to college so I can continue working with them. While touring colleges, I spoke with biology professors at many of the schools to discuss the possibility of bringing my collection so that I may continue working to conserve them. Along with Mantella crocea, I also have Mantella auriantiaca, Mantella ebenaui, Mantella pulchra, and Mantella viridis. My focus for the past year has been on the herpetofauna of Madagascar, including a couple of other frogs from the family Mantellidae as well as geckos from the genus Phelsuma.