Role of fish and wildlife in lakes

Aquatic plants and algae are the primary producers in the lake ecosystem, that is they convert sunlight and nutrients through photosynthesis into plant growth and oxygen. These plants are the basis of a complex food chain that supports a web of life ranging from tiny microorganisms, to fish, to shoreland animals that eat fish. These animals are called consumers. Consumers can live throughout the lake, although a lack of oxygen in bottom waters and sediments may limit their abundance in some places. In contrast, how deeply sunlight can penetrate lake water limits where photosynthesis can occur.  
 
Zooplankton, small animals that swim about in open water, are primary consumers. They graze on algae, bacteria, and partially decayed organic material (called detritus). Many species of zooplankton are microscopic, although some can be seen with the naked eye.
 
There are some fish and invertebrates (such as worms, insects, and crayfish) that eat the zooplankton; these are secondary consumers. Invertebrates like clams and bottom feeding fish (like catfish) are called benthic organisms. They may filter food out of the water (as clams do) or eat natural debris (called detritus) that sinks to the lake floor. Benthic organisms are major consumers and are important recyclers of nutrients otherwise trapped in sediments.

The best known group of aquatic consumers is fish. Many small fish, such as sunfish and perch, primarily eat zooplankton. Larger fish and other carnivorous animals—such as loons, grebes, herons, and otters—prey on these smaller fish.

Many features—lake bottom composition, chemical characteristics, shoreland composition, water quality, lake depth—influence what species of plants and animals will thrive in the lake. Bass and pike are found in lakes that have beds of aquatic plants suitable for spawning. Walleyes spawn on a gravel bottom. Lake trout live only in very clear lakes with cold, well-oxygenated deep water. In contrast, carp are adapted to warm turbid, low oxygen lakes with mucky, high organic matter bottoms.

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Managing your lakefront property for fish and wildlife

 

Leave natural features that help wildlife

You can provide a strong foundation for wildlife habitat on your property by protecting existing natural features that are valuable to wildlife. Some useful features include:

• Large, dead standing or cavity trees (used by many birds for nesting and roosting or dens for some animals)
• Large, dying trees (woodpeckers search for insects and bats roost under loose bark)
• Seasonal pools and wetlands (used by amphibians for breeding)
• Berry “tangles” (cover for many species of wildlife)
• Logs and branches in the water (basking areas for turtles and cover for fish)
• Lakeshore and stream bank burrows (homes of weasels, otters and muskrats)
• Sandy soils with good sun exposure (used by turtles for nesting areas)
• Rock piles (cover for snakes and small mammals)
• Large trees overhanging the water (feeding perches for flycatchers, kingfishers, osprey and other birds)
• Fallen logs on the land (preferred habitat for
  some salamanders)
• High, sandy banks (nesting sites for kingfishers, bank swallows and rough-winged swallows)

Let fallen trees lie

Leave fallen trees in the water to provide habitat for fish and wildlife. Fallen wood forms critical habitat for tiny aquatic organisms that feed bluegills, turtles, crayfish and other critters. Many species—such as turtles, frogs, dragonflies, songbirds, and otters—use downed trees as both a feeding area and hiding place. Fallen trees are also an important source of nutrients and minerals for our lakes, and they help protect shorelines from erosion.

Plan your pier

You may have heard the common myth that piers make good fish habitat, but recent studies are showing that the opposite is true. Often people can see fish under their piers because plants have been removed, and exposed fish are darting from one patch of plant cover to another. Aquatic plants are important habitat and provide hiding places for fish. Piers can shade out plants and can "break" contiguous shoreland habitat. In addition to shading plants underneath the pier, property owners often clear additional plants away from their pier in order to launch boats. Although you may be able to see more fish under a pier, odds are far more fish are living in the aquatic plants adjacent to the structure.  

Installing one reasonably sized pier will not significantly affect the health of the lake, however the cumulative effect of installing many piers may impact shoreland habitat and overall lake quality. The larger the pier the more shoreland area it can potentially disturb and shade.

 

 

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