The Park

Fish Habitat

Everyone needs a place to live. That includes fish. We all know that fish live in water, but most fish are very particular about the water they live in. They need clean, healthy habitats where they can live and find good food, shelter and places to reproduce.

What defines fish habitat? Fish habitat is any area in an aquatic ecosystem that provides something important that fishes need to live. This can include:

Food
Like all animals fish must eat. The type of food an area can provide for fish depends on both the type of river or lake bottom (substrate) and the type of land along the shoreline (the riparian zone).

Shelter
Fish need places to hide from predators and competitors. They may also need places to rest if there is a strong current. Areas behind rocks, around sunken logs and branches, among patches of vegetation, or in deep pools or undercut banks all provide fish with places to escape.

Migration routes
Fish often travel a great distance between where they live and eat, and where they reproduce. Fish must be able to swim through all the areas in between if they are to be successful in their travels.

Places to reproduce
Most fish are very particular about where they will lay their eggs and raise their babies. They will only reproduce if they can find the right type of substrate and the right water quality.

Water quality
Most fish species have very specific temperature ranges in which they can live. They are also sensitive to sediments, pesticides or any other pollutants in the water. All of the places fish need for habitat must have the right water quality or they will not be able to live there.

Habitat Protection and Conservation

Protecting fish has a long history in Canada. The Fisheries Act was first passed in 1868, only one year after Confederation. That makes it one of Canada's oldest laws. It is against the law to damage fish habitat in Canada. Any time a project might cause Harmful Alteration, Disturbance, or Destruction (HADD) of fish habitat, there must be an approved plan to either repair any damage, or to make up for it by improving fish habitat somewhere else.

There are many things that people do that can damage fish habitat, often without even knowing it. When we damage fish habitat, fish lose their homes, and we lose the fish. Fish habitats can be damaged by changes big and small. A multi-million dollar hydro project can take its toll, but so can a poorly installed culvert. But if we are careful, there are many ways we can protect fish habitat so that fish will always have healthy places to live.

For most fish species, areas along banks of streams and rivers, and near the shores of lakes are very important. In this shallow area called the littoral zone, enough light reaches the bottom to support aquatic plants. Small fish use the plants growing near the shore for food or for places to hide. Insects and other invertebrates living here are food for other fish. Bigger fish that may live in deeper water often come to these areas to hunt for smaller fish. Since these areas are so important for fish, it is very important to look after them properly.

Learn some of the Threats To Fish Habitats and some things we can do to Protect them. Can you find ways that you can help?