MADAGASCAR TOMATO FROG

Characteristics

It’s clear how the Madagascar tomato frog got its name: that vibrant, red-orange color is hard to miss. The females, which are larger than males, have the brightest red colors, while the males are more orange or orange yellow. Why stand out instead of blending in? As with many animals that are red or orange, the color is a warning: don’t eat me, I’m toxic! And tomato frogs are spectacularly so. If attacked, they produce a white, gooey, sticky secretion from their skin that acts like glue in the mouth of a predator like a snake. It’s also been known to cause an allergic reaction on human skin. Yikes—definitely better to steer clear!

Habitat

Tomato frogs are native only to Madagascar, and there are three different species found on the island, Dyscophus antongilii, D. guineti, and D. insularis. D. antongilii is known as the Madagascar tomato frog, or the sangongon in Malagasy. It is found in the northeast of the island around Antongil Bay and south to Andevoranto, living in subtropical or tropical moist lowland forests, rivers, swamps, and freshwater marshes.

Tomato frogs do not have webbed hind feet, so swimming is not their strong suit. They prefer calm, slow-moving water and forage for food on land. They are adaptable, though, and are also found in areas of human habitation, including plantations, gardens, urban areas, ponds, canals, and ditches.

Diet

Madagascar tomato frogs are insectivores, feeding on small invertebrates like beetles, mosquitoes, and flies. They are opportunistic ambush predators, foraging among plants and leaf litter to find a meal. They gulp down invertebrates they happen to come across on the rainforest floor, and they may also wait near water to ambush food flying by, nabbing it with their sticky tongue.

Behavior

Madagascar tomato frogs are solitary and mainly active at night, moving around the forest floor hunting for insects to eat. During the day, they usually hang out in mud or under leaf litter. In addition to their warning coloration, tomato frogs can inflate themselves when threatened, making them look bigger and harder to swallow. They have a loud call, usually heard from males during breeding season as they compete to attract females.

Reproduction and Life Cycle

Madagascar tomato frogs are polygynandrous: both males and females mate with multiple partners. They breed regularly year-round, although most often after heavy rainfall, which typically occurs in February and March. Females lay a clutch of 1,000 to 1,500 eggs on the surface of a pond or pool, and brownish tadpoles hatch from the small black-and-white eggs about 36 hours later. The tadpoles are filter feeders, initially about six millimeters long. They undergo metamorphosis into yellow juvenile “froglets” about 45 days after the eggs were laid; adults then become reproductively mature between 9 and 14 months of age.

Conservation and Threats

At one time, Madagascar tomato frog populations declined due to their value in the pet trade—the frog’s bright color made it popular among hobbyists, and they were collected and sold by poachers. In response to this, captive breeding programs were established at several zoos, and the species was also listed under the Convention on International Trade in Endangered Species (CITES), in an effort to prevent wildlife trafficking. These two efforts have effectively halted commercial exploitation, and the species is now listed by the IUCN Red List as “Least Concern.” Habitat loss and pollution of waterways used for breeding do remain potential threats long term.