The threatened Amazonian pink dolphin faces a new challenge: a bacteria discovered in its blood by researchers from the Animal Health Research Center (INIA-CSIC). This discovery was recently published in Emerging Infectious Diseases and raises concerns about the health of these aquatic species.
New bacterial threats to the Amazonian pink dolphin
Scientists found DNA of hemotropic mycoplasma in two types of Amazonian dolphins: the Bolivian pink dolphin (Inia boliviensis) and the Amazonian pink dolphin (Inia geoffrensis), in more than 60% of the samples analyzed. Surprisingly, the Amazonian manatees (Trichechus inunguis), animals closely related to elephants, showed no presence of this bacteria.
The capture of the dolphins, necessary for the study, was facilitated by former local fishermen, who now collaborate in their conservation. Despite the intelligence of these animals, which makes their capture difficult, the scientific team managed to obtain the necessary samples minimizing stress thanks to expert veterinarians.
Hemotropic mycoplasmas are usually found in terrestrial mammals such as humans and sea lions. The appearance in dolphins and manatees, both considered indicators of the health of the Amazon ecosystem, is a worrying novelty for the biodiversity of the rainforest.
According to Aricia Duarte Benvenuto, the main author of the study, it is still unclear how these bacteria are transmitted in aquatic environments. While on land, parasites such as ticks are suspected, the mechanism in the water remains a mystery, requiring more research to assess its impact on the health of the dolphins.
Additional environmental pressures
In addition to bacterial threats, dolphins and manatees face severe environmental risks. Mercury contamination of rivers, a result of gold mining, along with deforestation to create pastures and climate change, which intensifies droughts in the region, endanger their survival.
The illegal hunting of dolphins to use them as bait in commercial fishing also represents a significant risk. According to Carlos Sacristán Yagüe, a veterinarian at INIA-CSIC, ongoing research is crucial, having previously discovered two types of herpesvirus in these species. This work is vital for the conservation of wildlife.
Reference: Duarte-Benvenuto A et al. “Hemotropic Mycoplasma spp. in Aquatic Mammals, Amazon Basin, Brazil”. Emerging Infectious Diseases.



