Scientists baffled by dolphins' strange peeing behavior in the Amazon

In the Amazon River, researchers have observed unusual behavior among Amazon river dolphins, known as botos. From 2014 to 2018, Canadian biologists documented 36 cases of 'aerial urination' where these dolphins flip belly-up to urinate above the water while a receiver male seeks out the stream with its snout. This behavior is particularly common in boto dolphins, which are known for their playful nature and less fearful disposition compared to other dolphin species. The study suggests that this act may serve as a form of communication, possibly aiding in mate selection through scent marking. Scientists note that aerial urination, while rare or seldom observed in other cetaceans, appears to be relatively frequent among botos. The documented occurrences typically involve two male dolphins: one that urinates and another that actively approaches the stream. The interesting behavior lasts approximately 10 seconds, with many observations indicating the presence of a 'receiver' dolphin. This finding highlights a distinct social interaction between dolphins which may extend beyond mere elimination of waste. A surprising aspect of this behavior is the potential use of chemical communication in an aquatic environment where traditional markers, such as territorial urine in land mammals, are less effective. Dolphins have demonstrated an ability to detect odorants in both air and water, which raises questions about how they utilize their environment for social interactions. The research indicates that the bristles on the boto's snout may act as chemical sensors, aiding them in detecting the pathways of urine streams of other dolphins. In conclusion, understanding this peculiar behavior not only contributes to marine biology but also prompts further research to explore the communication methods employed by dolphins. The study’s insights into the boto's social dynamics open new avenues for understanding how aquatic mammals interact and communicate in their natural habitat. Researchers are hopeful that follow-up studies will elucidate this intriguing phenomenon and its implications for dolphin behavior and communication.