What would happen if manta rays decreased in amount?

If manta rays decreased in number, it could disrupt the marine ecosystem they inhabit. As filter feeders, they help maintain the health of ocean waters by consuming plankton and small fish, which can prevent overpopulation of these species. A decline in manta rays could lead to an imbalance in the food web, resulting in increased competition for resources among other marine species. This imbalance may ultimately affect fish populations and the overall biodiversity of their habitats.