The Ecuadorian toad who broke the silence with singing after a century

With photos and video by Rodrigo BUENDÍA ///Quito, 16 Mar 2022 (AFP) - A very sharp sound in the forest caught the attention of Ecuadorian biologist Jorge Brito. He thought it was the cri-cri of a cricket, but he found a kind of toad with a prominent nose that since its discovery, a century ago, science believed to be dumb.” At first I thought it was some cricket that was out there vocalizing, but I noticed it and I was attentive,” recalls Brito, from the National Institute of Biodiversity (Inabio) .What he saw next was a toad that “although he didn't inflate the uvular sac, there was a little flicker” on his chin. again made a sound. It was not the common croak of toads, but a very fine “ruuur-ruuur”. By chance, he found the evidence that brought down the idea that this species could not sing because of its particular vocal anatomy. In February, the journal Neotropical Biodiversity reported the finding. In their article, Brito and fellow Ecuadorian biologist Diego Batallas described the sound of this species that inhabits the Amazonian mountain ranges of Cutucú and the Condor. The latter extends from Ecuador to Peru.” This particular song by Rhinella festae is the first time it has been recorded and it is somewhat surprising because, in a few words, it should not sing,” he tells AFP Batallas.This variety is known as the toad of the Valley of Santiago. With brown and rough skin, it can measure between 45 and 68 millimeters and is characterized by the head ending in a nasal prominence. The International Union for the Conservation of Nature (IUCN) included it on its list of nearly threatened animals. The dominant frequency of his singing is in a range of 1.21 to 1.55 kilohertz, with one to two notes multipulsed, and an average duration of 0.72 seconds. “A very subtle sound and very difficult to hear in the field,” says Batallas, who before becoming a biologist was a chorus singer at a conservatory. - Everyone sings - Rhinella festae toads lack sack and vocal clefts. The first is a cartilage that inflates and acts as a speaker; the second, a sort of valves that regulate the entry and exit of air. Located under the chin, the vocal sac allows amphibians to amplify their song so that it can be heard more than 1 km away. The fine sound thread of the Rhinella festae would prove that all the species of toads sing.” Most likely, there are species that have gone unnoticed and that due to evolutionary processes that we do not know - which can be anti-predatory, which can be effects of the environment - do not need their sounds to be heard far away,” says Batallas. In the case of the Rhinella festae, their song is an announcement, as if it were a card of presentation. In other species croaking is associated with courtship and the defense of territory. Ecuador, a small but megadiverse country, has 658 species of amphibians registered. Of these, 623 correspond to toads and frogs and almost 60% are at risk or critically endangered of disappearingOnly Brazil and Colombia have more species of amphibians than Ecuador. - Sound identity - In a laboratory in Quito, Brito has the stuffed specimen of the Rhinella festae toad that surprised science. He is still excited when he remembers the chance that led him to discovery.In 2016, he compiled an inventory of the fauna that lives between the Upano and Abanico rivers, in the Amazonian province of Morona Santiago, on the border with Peru. One night, he says, he entered the forest and caught the sound that he first confused with that of a cricket. He contacted Batallas so that both, in the laboratory, will hear the call of the toad. “The first time I heard I said: ugh! This doesn't sound like a toad, it's like some kind of a little bird, a trinito. It does not have the characteristic of an amphibian”, says Battles. Already with the certainty that it was a song never recorded by science, the researcher stresses the importance of finally having a sound identity like most species of toads. This finding allows the implementation of less invasive methods of research, since the entry of people to fragile ones is limited habitats to avoid the manipulation of specimens.pld/sp/vel/ll —