FOR anglers nothing beats catching a big fish. Commercial fisherfolk also prefer to haul in big specimens. Unfortunately, in recent years, research has shown that selectively capturing the largest fish has worrying ecological consequences. In some species the large ones are the healthiest ones, and so the ones most likely to breed successfully. In others they are the oldest, and so the most experienced at eluding predators or securing resources, such as food and breeding sites. In tropical wetlands, such as the Pantanal and Amazon regions of Brazil, the largest fish are also vital in dispersing seeds—and thus maintaining and regenerating habitat.
Trees in these areas fruit most prolifically during the summer, when local rivers burst their banks and flood the land, making those fruit available to fish, which gladly gobble them up. Then, as the fish swim around the floodplain, they pass the seeds inside those fruit, which often remain intact, as part of their faeces. These…Continue reading