For the decomposers I found slugs ... If all of the top predators leaves or dies, such as herons in a pond ecosystem, there will be an increase in the number of smaller animals, such as fish ...

Although natural ponds differ from the mesocosms in ... grazers in turn consume phytoplankton, periphyton, and decomposers. The ecosystem response variables also included ecosystem productivity ...

They found that ponds with fish produce fewer larval ... Herbivores in terrestrial ecosystems are less abundant but decomposers are much more abundant than in phytoplankton dominated aquatic ...