Which group of organisms may be used in biological control to regulate aquatic plant populations?

The group of organisms that may be used in biological control to regulate aquatic plant populations consists of herbivorous fish and insects. These organisms are specifically chosen for their ability to naturally feed on aquatic plants, thus helping to manage their growth. Herbivorous fish, such as certain species of carp and tilapia, can consume vast amounts of aquatic vegetation, while insects may include various larvae or beetles that target specific plants.

The use of such biological control agents is advantageous as it reduces the need for chemical herbicides, leading to a more environmentally friendly approach to managing aquatic ecosystems. Moreover, these organisms can often establish self-sustaining populations within the targeted environment, providing long-term control over invasive or excessive aquatic plant species.

Other groups, like amphibians and reptiles, while they may have some impact on the ecosystem, typically do not feed specifically on aquatic plants to the extent required for effective management. Similarly, predatory birds are not primarily focused on controlling plant populations, as they are more concerned with hunting prey rather than managing aquatic vegetation. Algae and fungi can play roles in ecosystems and may interact with plants, but they are not suitable biological control agents for regulating plant populations in the way herbivorous fish and insects are.