The blue poison dart frog, scientifically known as Dendrobates tinctorius azureus, is a captivating amphibian celebrated for its vibrant coloration and intriguing life history. This article delves into the dietary habits of this fascinating creature, exploring what it eats in the wild and in captivity, and how its diet contributes to its unique characteristics.
Introduction to the Blue Poison Dart Frog
The ‘azureus’ form of Dendrobates tinctorius is a medium-sized frog characterized by its hunchbacked posture, more pronounced in females, and striking coloration. Its legs are commonly an azure-blue, the belly darker blue, and the back sky-blue. An irregular pattern of various sized black and dark blue spots cover the background coloration, with the majority of spotting located on the frog’s back and head. Occasionally, a dark blue or black mid-belly stripe is present on its ventral surface. The skin is mostly smooth, with some granular texture on the rear ventral surface and thighs. Each foot has four toes, each with a wide, flattened tip and well-developed adhesive pads for gripping slippery surfaces.
Natural Habitat and Distribution
Primarily found in the south-central area of Surinam, in a region known as the Sipaliwini Savannah, the blue poison dart frog's habitat is surrounded by rainforests and their tributaries, part of the Amazon basin. Adult frogs and froglets inhabit small, isolated, dark, and humid patches in rainforests or near streams, attached to moss-covered rocks, in crevices, or under floating plants. The forest daytime temperatures range from 72 to 81 degrees Fahrenheit (22 to 27 degrees Celsius), dropping to 68 degrees Fahrenheit (20 degrees Celsius) at night. This restricted habitat makes the species particularly vulnerable to environmental changes.
Dietary Habits in the Wild
Dendrobates azureus is primarily an insectivore, consuming a variety of small insects and other arthropods. Like most poison dart frogs, this species uses its vision and tongue to capture prey. Once prey is seen, it darts out a sticky tongue to zap unsuspecting prey. Their diet includes:
- Ants
- Fruit flies
- Termites
- Young crickets
- Tiny beetles
- Mites
- Spiders
- Maggots
- Caterpillars
The Role of Diet in Toxicity
One of the most remarkable aspects of the blue poison dart frog is its toxicity. The toxic compounds in the skin, known as lipophilic alkaloids, are derived from their prey, particularly ants and tiny beetles. After consuming prey containing these alkaloids, the frogs become unpalatable to predators. This serves as a defense mechanism, warning potential predators of their poisonous properties through their bright coloration, a phenomenon known as aposematic coloration. The skin is covered with a myriad of glands that secrete alkaloid poisons. This is released on contact, attacking the neuromuscular apparatus of the predator via the bloodstream.
Read also: Weight Loss Meds & BCBS
Captive Diet
In captivity, the diet of D. azureus must be carefully managed to ensure their health and well-being. At the Aquarium, ‘azureus’ are fed a diet that includes crickets, wingless fruit flies, meal worms, and earthworms. Captive-bred frogs lose their poisonous properties because their diet lacks the toxic compounds found in their natural prey.
A typical captive diet includes:
- Crickets
- Wingless fruit flies (Drosophila melanogaster and Drosophila hydei)
- Mealworms
- Earthworms
- Springtails and isopods (for bioactive vivariums)
Feeder insects should be dusted with vitamin/mineral supplements, such as Vitamin A twice monthly and Calcium on the rest of their meals. Repashy is an example of a high-quality supplement.
Feeding Practices in Captivity
Poison dart frogs eat insects. Most poison dart frogs prefer smaller foods. Any poison dart frogs should readily eat Drosophila melanogaster fruit flies. Frogs large enough (~1 inch) should do well with Drosophila hydei fruit flies and pinhead crickets. They can also snack on the springtails and isopods that can be used to help maintain a bioactive vivarium. All feeder insects should be dusted with vitamin/mineral supplements.
Dart frogs are carnivores and like to eat things that are much smaller than they are. In captivity they eat fruit flies, pinhead crickets, springtails, and isopods.
Read also: Managing a Blue Spa: Key Responsibilities
Housing and Environmental Requirements
To thrive in captivity, blue poison dart frogs require specific environmental conditions that mimic their natural habitat.
- Vivarium Size: A minimum of 5 gallons per frog, with at least 10 gallons even for a single frog.
- Temperature: A temperature range of 65 F-80 F, ideally in the low to mid 70s. Temperatures over 85F are dangerous.
- Humidity: A humidity range of 80-100%, though they can tolerate humidity down to 50% for short periods if water is accessible.
- Water: Chlorine- and chloramine-free water, achieved through bottled spring water, charcoal-filtered tap water, or tap water aerated for at least 48 hours. Water conditioners can also be used.
- Water Changes: Regular 50% water changes to protect the biofilter of the tank.
Social Behavior and Reproduction
‘Azureus’ reaches sexual maturity at ten to twelve months of age. This morph usually breeds once a year during the rainy season. Males position themselves on a leaf or rock and quietly call to attract a female. Females follow these calls to find the male. If more than one female responds, the females fight over the male. The victorious female begins the courtship ritual by gently stroking the selected male’s snout and back with her front legs. The courtship may include wrestling and chasing. If courtship is successful, the male leads the female to a secluded, moist, and mossy area he has chosen that is near a water source and underneath logs or rocks to mate and lay eggs. The male climbs onto the female’s back and grasps her with his front legs. He externally fertilizes the clutch of five to six gelatinous eggs she lays. Although the female may help, the male is most commonly the primary caretaker of the eggs.
After a ten- to eighteen-day incubation, the tadpoles hatch. At hatching they have poorly developed gills, a toothless mouth, and a tail. The tadpoles wriggle onto their father’s back to be carried to an individual nest in a small pool of rainwater in a tree trunk or a cup-like structure in a bromeliad plant. The tadpoles now begin to metamorphose into froglets. Their gills are grown over by skin, eventually disappearing to be replaced by lungs. Teeth and rear legs develop. The head becomes more pronounced and the body elongates. Front legs develop and the tail becomes a stub.
Conservation Status and Threats
In 2014, the International Union for Conservation of Nature (IUCN) Red List of Threatened Species listed Dendrobates tinctorius as Least Concern; however, the studies that led to this listing did not specifically include the “azureus” morph. Restricted as the Blue Poison Dart Frog is to some small pockets of rainforests on the Sipaliwini Savannah, its habitat is threatened by deforestation, an industry that continues to be significant. There is also a demand for these colorful frogs in the international pet trade. Because of these pressures, “azureus” is believed to be one of the most threatened of all poison dart frogs in Central and South America. Captive breeding programs in the United States and Europe are meeting some of the pet trade demand for this frog.
The Blue Poison Dart Frog is believed to be rare in Surinam, The Surinam government protects this poison dart frog by requiring visitors who go to Surinam’s Four Gebroeders Mountains to have permission. They are asked the reason for the visit and on returning, may be checked to prevent poaching. The morph, D.ti.‘azureus’, is not listed by CITES, the Convention on International Trade in Endangered Species of Wild Fauna and Flora. CITES is an international agreement among governments. The United States is a CITES Partner.
Read also: Understanding BCBS Weight Loss Benefits
Climate change: Many scientists believe that over time global climate change and rainforest degradation together could lead to increased temperatures and changing rain patterns in the Amazon basin. As a result of these changes, the region’s forests, water availability, and ultimately the animals and plants that currently inhabit the rainforests would be affected.
Adaptations
Bright coloration serves as a warning to would-be predators of its poisonous properties. Another important adaptation is the toxins within its skin that are capable of paralyzing or even killing potential predators. They are diurnal rather than nocturnal. This species of frog is bold, aggressive, and very territorial, especially the males which are known to fight over territories. However, both sexes are known to defend their territories from frogs of the same species as well as those of other species. Aggressive behavior in D. azureus usually consists of calling, chases, and wrestling. Wrestling usually occurs between those of the same sex, but can occur between males and females. These frogs can make do with fewer eggs and thus spawn larger ones, which supply more yolk for each developing embryo.