What is the difference between a pond and a lake? To start with, a pond is usually smaller than a lake. A pond usually has mostly still water, while a lake may have currents. Ponds are overall much more shallow than lakes, which can be very deep. Ponds may be fed by a small stream, whereas a lake is usually fed by several streams. The water temperature of a pond is usually the same throughout, while a lake may have layers of different temperatures in its depths. Lastly, ponds have more plant life than lakes. Plants may completely cover a pond, but lakes only have plants on the edges.
Below is further description of pond characteristics:
The surface film is a thin, strong layer at the surface of the pond. Many tiny animals live on the film. Water striders, for example, can walk on the film, and pond snails can glide upside down on it. Some plants, especially duckweed and lily pads, float on the film. The surface film is also very important to aquatic insects, which use it to metamorphosize (change) from the nymph (juvenile) stage to the adult stage.
The pond's bottom is usually made of mud. Many aqatic insects, crayfish, leeches, and other creatures live in, or on top of, the bottom. In winter, turtles and frogs bury themselves in the bottom to hibernate.
Many trees, shrubs, grasses, and wildflowers do well in moist soil with lots of sunlight. This makes pond edges great places to grow. These plants provide cover for animals that visit the pond and shade for animals that live in the pond.
These plants "emerge," or rise up, out of the water. Roots of emergent plants are in the mud bottom, underwater, near the edge of the pond. Leaves and flowers are above the water's surface. Examples of emergent plants include cattails, sedges, bulrushes, reeds, and arrowheads. Emergent plants provide important shelter for pond animals, such as frogs, snakes, and muskrats.
These plants float on the surface film of the water. Some, the duckweeds, float freely, with tiny roots dropping down into the water. Others, like lily pads, have wide leaves that float on the surface and long stems that reach all the way down to the pond bottom where roots lay in the mud. Lilies grow in huge colonies and can sometimes cover the entire surface of a pond. Floating plants provide cover for fish and other underwater creatures.
These plants spend their entire lives underwater. Bladderworts and horntails are examples. Submergent plants provide structure for aquatic insects to climb on and food for animals, such as ducks and snails.
Microorganisms are tiny creatures and plants that you need a microscope to see. Ponds are the best place to find them. Tiny insect larvae, crustaceans, protists, bacteria, and algae are some of the most common types of organsims found in a pond. These organisms are food for baby fish, aquatic insects, tadpoles, newts, and other animals.
These are insects that lay their eggs in water. Eggs hatch into a nymph stage underwater and most of the insects' lives are spent there. Some aquatic insects prefer streams, but most can be found in ponds. When the nymphs are ready to change into adults, they swim or float to the surface film, where they metamorphosize into the form of insects you are most familiar with. Dragonflies, mosquitoes, mayflies, water striders, diving beetles, crane flies, and whirligigs are some examples of aquatic insects.
Logs and Snags:
Many ponds have dead logs from fallen trees in them. A dead snag is a tree that is dead, but still standing. These are most common in beaver ponds, but they are also found in man-made ponds. Logs provide basking spots for turtles and snakes and resting spots for ducks and geese. Snags are great perches for birds, like kingfishers and swallows.
Beaver Lodges and Muskrat Houses:
Ponds are the most common home of beavers and muskrats. Beavers are often responsible for making the pond in the first place. By building a dam, beavers create a pond from a marsh or stream. Beaver lodges made of branches, sticks, and mud may be in the center of the pond or near an edge. A larger dam may be at one end of the pond, holding the water in. Muskrat houses are smaller than beaver lodges and are made mostly of cattails and grasses.
Ponds are home to a great variety of wildlife, including fish, reptiles, frogs, birds, insects, crayfish, snails, leeches, and others. Ponds also attract visiting wildlife, searching for water or food.