The Mountain Chicken is not a bird, but one of the largest species of frogs in the world, the Leptodactylus fallax. This massive, ground-dwelling amphibian is native to the Caribbean islands. It is critically endangered, with wild populations confined to just two islands. Its severe decline has made it a flagship species for global amphibian conservation efforts.
Physical Characteristics and Naming
The Mountain Chicken frog is a large amphibian, reaching up to 22 centimeters in length and exceeding 900 grams in weight. Its robust build makes it the largest native frog in the Caribbean. Coloration is variable, generally appearing in chestnut-brown or reddish-brown hues, often patterned with darker bars or spots. Males have distinct, hardened spurs on their thumbs used during breeding.
The common name, “Mountain Chicken,” references its significance as a traditional food source. Its large hind legs provided substantial meat, which locals reported tasted similar to chicken. This culinary popularity led to its name and, historically, to unsustainable harvesting.
Habitat and Unique Behaviors
Historically, the Mountain Chicken was found on several islands in the Lesser Antilles, but its range is now restricted to Dominica and Montserrat. The frog thrives in tropical and subtropical moist forests, often near streams, but is highly terrestrial. During the day, it hides in underground chambers, rock crevices, or under dense leaf litter to escape heat and predators.
This species exhibits a unique and complex reproductive strategy. Breeding takes place in burrows, where the male attracts a female with a characteristic “whooping” call. The female produces a foam nest inside the burrow and lays her eggs there. Both parents guard this nest until the eggs hatch and the tadpoles begin to develop.
The most distinctive parental behavior involves the female feeding the developing tadpoles. She purposefully lays unfertilized eggs, known as trophic eggs, which serve as the sole source of nutrition for the young. The tadpoles develop entirely within the foam nest and burrow, bypassing the free-swimming aquatic stage common to most amphibians. After approximately 45 days, the young froglets emerge from the burrow.
Primary Threats to Survival
The decline of the Mountain Chicken is overwhelmingly attributed to the fungal disease, Chytridiomycosis. This illness is caused by the microscopic aquatic fungus Batrachochytrium dendrobatidis (Bd), which has decimated amphibian populations worldwide. The fungus attacks the frog’s keratinized skin, interfering with water and electrolyte regulation, which leads to heart failure.
The chytrid fungus arrived in Dominica around 2002, causing the population to plummet by over 99 percent. It reached Montserrat a few years later, with similarly devastating results. The disease proved fatal to nearly every exposed individual, pushing the species to the brink of extinction.
While the fungal disease is the immediate cause, other factors contributed to its vulnerability. Historical over-harvesting reduced population numbers and genetic diversity before the fungus arrived. Volcanic activity on Montserrat also destroyed vast tracts of suitable habitat, confining remaining frogs to small, isolated areas.
Conservation Efforts
The Mountain Chicken is listed as Critically Endangered by the International Union for Conservation of Nature. Conservation hinges on intensive, collaborative efforts known as the Mountain Chicken Recovery Programme. These efforts focus on protecting remaining wild individuals and establishing safety net populations outside of their native habitat.
Captive Breeding and Research
Captive breeding programs have been established in biosecure facilities, including international zoos and conservation centers. These ex-situ populations are maintained as a genetic reservoir, safeguarding the species from wild threats. Scientists are investigating whether any remaining wild frogs possess a natural resistance to the Bd fungus.
Reintroduction Challenges
Reintroduction attempts face immense challenges due to the persistent threat of Chytridiomycosis. Conservationists are exploring innovative techniques, such as using probiotics to boost the frogs’ skin immunity and managing small, semi-wild enclosures. Survival depends on finding a practical way for the species to coexist with the deadly fungus in the wild.