Plankton (singular plankter) are a diverse group of organisms that live in the water column of large bodies of water and that cannot swim against a current. They provide a crucial source of food to many large aquatic organisms, such as fish and whales.lankton are primarily divided into broad functional (or trophic level) groups: 1  Phytoplankton (from Greek phyton, or plant), autotrophic, prokaryotic or eukaryotic algae that live near the water surface where there is sufficient light to support photosynthesis.
Tree swallows breed between May and September. They raise one brood per year. Tree swallows usually nest solitarily. However, they may nest near other tree swallows if nest cavities are close together. Tree swallows build their nests in late April or early May. Their nests are usually built in holes in dead or live trees or in hollow stumps. The female builds the nest using grasses, mosses, rootlets, and aquatic plants.
Reproduction/babies. To make the nest the male and female will collect dry grass or palm trees leaves and lay them down in a clean place. Once the nest is made the male will find a white pebble the size of a goose egg and place it beside the nest, scientist think it is to help grind the food in the stomach.