If you've ever wondered what a crocodile would make, we'll admit you didn't expect it to be like this. A West African pygmy crocodile screamed like an old cow — a discovery that may be useful to conservationists as they make it easier for them to track down the tiny reptile.
The African dwarf crocodile (Osteolaemus tetraspis) is the smallest living crocodile species, but its small size does not prevent it from producing a unique and bizarre sound. The recordings reveal an eerie sound that resembles a cow's bark, as well as three other vocalizations, which are also similar to other familiar sounds.
This discovery is not just a source of joy, it also contributes to conservation efforts (O. tetraspis is listed as vulnerable on the IUCN Red List), providing a reference for species identification. "These data can also contribute to extensive biodiversity monitoring and anti-poaching activities, as well as to improve our understanding of crocodile ecology and behavior," the study authors wrote in the study.
In fact, acoustic technology is becoming a valuable tool for monitoring species and biodiversity. They are especially useful for crocodiles that live in the forest, such as O. O. tetraspis, because they are difficult to spot with the naked eye alone.
Unfortunately, for many species, their sound stock data is relatively insufficient, including O. tetraspis.
"It's really a species that no one knows about," lead author Agata Staniewicz told New Scientist.
But with the distinctive cow-like sounds they discovered, that may be about to change.
The team recorded and cataloged the calls of two adult African pygmy crocodiles in captivity, and that's how they discovered some surprises about this elusive creature. When they combined the 97 sound signals captured from the pair of crocodiles with 201 recorded in the field in Gabon, they were suspected of being O. When comparing Tetraspis's calls, the team found four types of calls that were not only found in both wild and captive crocodiles, but had never been identified in crocodiles.
They named the four genres "drums," "bass," "wind," and "cows," all of which come from their similar, familiar sounds. For example, "The Sound of the Wind" sounds like a howling wind, as its name suggests:
Low-frequency sounds (such as drums, bass sounds, and wind) can be hard to hear, but cow sounds so clear that you can't help but think of their names:
There is a Chinese alligator that also makes a cow sound, but other than that, it is almost impossible to hear this sound in any animal, Staniewicz told New Scientist, which makes O. Tetraspis became an odd presence among crocodiles, or one in a million.
When it comes to unexpected animal sounds, the call of this chaotic duck is even more out of place than the crocodile's cow call, which has been living in our minds since it learned to "speak" in 2021.
The study was published in the African Journal of Amphibians.