Animals inhabiting a lake comprise of microorganisms, arthropods, aquatic creatures, avian species, amphibians, reptiles and even mammals. These organisms form an integral part of the lake’s ecosystem – a concealed realm that exists within and around the water body. Let’s explore which lake animals might be dwelling in your nearby aquatic habitat!
Discovering the lake‘s inhabitants emphasizes the significance of lakes, which offer sustenance, hydration, refuge, solace, and camaraderie to its dwellers and guests. Who are these inhabitants? This piece introduces you to various animals that you may come across in your nearby or far-flung lake.
Types of Animals That Live In A Lake
Lakes, similar to the animals that inhabit them, vary in size and shape. The water in a lake is generally calm or sluggish, and the lake itself can be broad or narrow, shallow or deep. Interestingly, although most lakes are freshwater bodies, there are also saline (marine or saltwater) lakes.
When it comes to a lake’s ecosystem, there are two primary groups of inhabitants: abiotic elements that are not alive and biotic organisms that are. Among the biotic group, there are various significant classifications of creatures in a thriving lake. These lake animals are typically sorted based on their habitat and role in the lake’s ecosystem, which encompasses the food chain or web.
A lake contains various zones that can sustain diverse types of non-living animal life. The shoreline zone is known as the littoral zone, while the open water zone is called the limnetic zone. In some cases, depending on the lake’s dimensions and depth, this area may be split into two more zones: the upper euphotic and lower profundal. Lastly, the lake floor is home to the benthic zone.
Regardless of whether a lake is natural or man-made, it goes through three distinct life stages that determine which animals can inhabit it. Oligotrophic lakes are considered young and have clearer water with lower levels of biologic activity, making them less diverse in terms of organic life.
A lake that has a moderate amount of nutrients has matured and will showcase the greatest variety of animals.
A eutrophic lake is a body of water in the later stages of its life cycle, undergoing a transformation into a new type of ecosystem. As time passes, these lakes tend to evolve into dry land, wetlands, bogs or marshes. Having gained some knowledge about various types of lake animals, zones and life cycles, it’s time to focus on understanding the creatures that inhabit a lake.
Categories of Animals That Live In A Lake
Upon visiting a lake, it’s common to observe larger inhabitants like birds, fish, insects, and small animals; however, there exist hundreds of millions of tiny animals that reside in the lake which are only visible under a microscope. Despite their size, these creatures play a crucial role in maintaining life within and beyond the lake.
Lakes are inhabited not only by a diverse range of animals, but also by various types of plants that can be found in all the major zones of the lake and on its nearby shoreline. Additionally, many other animals tend to reside near lakes, often visiting them for drinking water, food, or temporary refuge.
There are four primary classifications of animals that inhabit a lake:
- The primary producers in a lake include small aquatic plants and animals.
- Animals with backbones (able to live entirely in water, on land and in water, or near the shore)
Let’s get acquainted with the lake‘s inhabitants – the animals!
Bacteria That Live In A Lake
Animals residing in a lake may go unnoticed due to the minuscule size of the bacteria. However, it is peculiar that without these bacteria, no other living organism would desire to inhabit the lake.
Animals that live in a lake include bacteria, which are unicellular creatures that come in various shapes such as rods, cones, spheres, or spirals. These microorganisms play a crucial role in breaking down and reusing organic matter to maintain the health of the lake’s ecosystem.
- The most prevalent bacteria found in lakes are Proteobacteria, which play a crucial role in decomposing ammonia.
- Alphaproteobacteria and gammaproteobacterial microorganisms assist in augmenting the level of dissolved oxygen present in the lake water.
- Cyanobacteria play a crucial role in sustaining photosynthesis in the entire lake ecosystem.
- Actinobacteria are beneficial microorganisms that aid in the decomposition of organic matter and transform nitrogen into other valuable substances.
- Bacteroidetes are a type of bacteria that prefer to inhabit the depths of the lake and play a role in decomposing larger organic compounds.
Primary Producers That Live In A Lake
Although not a commonly known term, primary producers play a crucial role in sustaining the lake ecosystem and its food chain by residing primarily in the upper limnetic and benthic zones, depending on their function and need for sunlight.
Both saltwater and freshwater lakes have primary producers such as phytoplankton, which are known as “plant wanderers,” and periphyton, which means “around plants.” Therefore, we are referring to aquatic plant species and microorganisms that thrive in their vicinity.
- Periphyton includes blue-green algae and green algae, which are among the most prevalent species found in a lake.
- Periphyton refers to a mixture of algae, bacteria, microbes, and detritus found in a lake.
- Lake aquatic plants such as water lilies, cattails, bulrushes, water lettuce, water hyacinth, moss and lichens are excellent examples of plants that thrive in a lake environment.
Invertebrates That Live In A Lake
Lake animals without a backbone or spinal structure inside their bodies are called invertebrates, which usually have an exoskeleton or shell that offers protection and are crucial to the food chain and ecosystem of the lake.
- Lake animals known as zooplankton are tiny creatures that can be either temporary or permanent parts of an animal’s life cycle, and they fall into four main categories: rotifers, protozoa, copepods, and cladocerans.
- Sponges. The most prevalent freshwater lake sponge is Spongilla lacustris, while Tethya aurantium (orange puffball sponge) and various Porifera sponge species inhabit saline lakes.
- Worms are present in lakes, including flatworms (planaria), roundworms (nematoda), and leeches (annelida).
- Mollusks are soft-bodied creatures that may or may not possess a shell and are not segmented. Bivalves, gastropods, and cephalopods are the three primary types of mollusks, with bivalve mollusks such as snails, mussels, and clams being the most prevalent species found in lakes.
- Arthropods, which possess a segmented body, a tough outer shell, and numerous legs, are among the animals that inhabit lakes, including millipedes, spiders, mites, fleas, midges, beetles, brine shrimp, lobster, crayfish, water striders, mosquitoes and other species.
Vertebrate Animals That Live In A Lake
Up to this point, we have been exploring the tiniest lake creatures that exist, some of which are only visible through intense magnification. However, our focus now shifts towards the vertebrates – animals that reside in a lake and possess a backbone or spinal column.
Except for fish, the majority of lake animals you are going to encounter will spend their time in both the water and on the ground.
Fish That Live In A Lake
A vast array of finned creatures inhabit both fresh and salty lake waters, with some being highly sought after for their delicious taste. Among the many species that reside in these aquatic environments are bass, perch, catfish, smelt, sturgeon, gar, minnows, goldfish, eels, carp, crappie and tuna.
Birds That Live In A Lake
Winged creatures frequently come to a lake for hydration and to capture aquatic creatures or bugs. They might also seek refuge on the water or in the shoreline area of a lake.
Herons, egrets, cormorants, ducks, gooses, swans, grebes, loons, killdeer, a variety of gulls, turns, stilts, sandpipers, willets, curlews, and many other local and migratory bird species can be found living in or near lakes or occasionally visiting them.
Amphibian Animals That Live In A Lake
Amphibians, which are ectothermic (cold-blooded) animals, regulate their body temperature, search for food, and lay eggs by moving in and out of the lake.
The most prevalent amphibian species that reside in a lake are salamanders, frogs, and toads.
Reptile Animals That Live In A Lake
When you think of lake-dwelling reptiles, turtles and crocodilians may be the most obvious, but there are many others to consider!
The most commonly observed lake animal species are turtles, snakes, iguanas, geckos, crocodiles, water dragons, and basilisks.
Mammalian Animals That Live In A Lake
Although some lake animals spend their entire lives in or around the lake, others split their time between the water and land.
Beavers, mice, rats, rabbits, river otters, muskrats, raccoons, nutria, water shrews and water voles are some of the animal species that can be found in a lake.
What Are Your Favorite Animals That Live In A Lake?
After being introduced to several lake animals, both visible and hidden, have you developed a preference for any particular animal or species? Share your favorites in the comments section!
Readers Also Liked
- Scott, S. “How Lakes Differ,” Lake Scientist, 2022.
- Walker, A.D. “What Type of Plants and Animals Live in Lakes?” Sciencing, 2021.
- Hurt, A. “Freshwater Habitat,” National Geographic, 2022.
- Balian et al. “The Freshwater Animal Diversity Assessment: An overview of the results,” Hydrobiologia Journal, 2008.
- Hoverman, J. “Ponds and Lakes: A Journey Through the Life Aquatic,” Nature, 2012.
- Logan, A. “Love your lake? Here’s what you need to know about its ecosystem,” The Lilly Center for Lakes & Streams, 2021.