MANAUS, Amazonas, Brazil — Located near the confluence of the Solimões and Japurá rivers, Lake Amanã, which means “the path of the rain,” is known as the home of the Amazonian manatee (Trichechus inunguis). During the dry season, when river levels drop, this mammal finds refuge and food there. It was on the beaches of the Amanã that biologist Michelle Guterres made a surprising discovery: manatee feces with strands of germinating grass. This observation was an important step toward confirming a hypothesis that so far had been only speculated about: the manatee is capable of dispersing seeds, thus helping plants migrate between different habitats. “I remember that, at the beginning of the research, my adviser insisted that the manatee was not a seed disperser,” Guterres says, recalling previous studies that had not found viable seeds in fecal samples. “And I told her: not that we know.” Guterres collected 96 fecal samples, 19 of which had plants germinating in them. One of the major challenges in the research was finding a significant amount of feces. As soon as a manatee defecates, its feces either dissolve in the water or are eaten by fish. That is why these animals were already known for fertilizing the waters, but their role as seed dispersers was a groundbreaking discovery. The extreme drought of 2023 made it easier to collect the samples, which were found on the beaches formed by low water levels. In October, Lake Amanã was only 20 centimeters (8 inches) deep. After that,…This article was originally published on Mongabay
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