1. Plankton:
- Phytoplankton: Microscopic algae that form the basis of the food web.
- Zooplankton: Tiny animals that feed on phytoplankton and other organic matter.
2. Microorganisms:
- Bacteria: Decomposers that break down organic matter.
- Fungi: Decomposers that aid in the breakdown of dead plant and animal material.
3. Plants:
- Submerged plants: Aquatic plants that grow completely underwater. e.g., waterweeds, Elodea.
- Floating plants: Plants that float on the water surface, e.g., duckweed, water hyacinth.
- Emergent plants: Plants that have roots in the water but their leaves and stems emerge above the water's surface, e.g., cattails, reeds.
4. Insects and other Invertebrates:
- Insects: Various insect species, including dragonfly larvae (nymphs), beetles, water striders, mayflies, and mosquitoes larvae.
- Crustaceans: Small crustaceans like water fleas (daphnia), copepods, and crayfish.
- Mollusks: Snails, clams, and mussels.
- Worms: Aquatic worms like leeches and flatworms.
5. Fish:
- Pond fish: Species such as goldfish, koi, bass, bluegills, and catfish.
- Amphibians: Frogs, toads, and salamanders.
6. Reptiles and Birds:
- Turtles: Different turtle species might inhabit ponds.
- Birds: Ducks, geese, and other waterfowls often visit ponds for feeding and breeding.
7. Mammals:
- Small mammals: Some species of rodents, muskrats, and bats might be found near ponds.
The specific composition of organisms in a pond can vary based on factors like location, water quality, temperature, and the presence of predators. Aquatic plant and animals adapt to their environment, such as having special structures for extracting oxygen from water or utilizing specialized feeding mechanisms to survive in the pond's ecosystem.