Underwater view of fishing structure


If you know where fish live, you will start catching more of them. Fish are always found where they have what they need. To catch more fish, you need to understand what they need to survive.

Now of course, not all fish can live in the same kind of water. Different species can tolerate different conditions, and some fish can cross environmental divides like Salmon. They live in saltwater but swim up freshwater rivers to spawn. Here are some of the major conditions that affect where fish will live:

• Amount of salt
• Amount of oxygen
• Types and amounts of food and prey
• Ambient water temperature
• Hiding areas available including cover and at the bottom
• Areas where they can breed
• The water salinity

The biggest factor that separates where fish can live is the level of salt in the water, or the salinity. Some fish can live in freshwater and saltwater, but the big majority can’t. Essentially there are 3 types of water environments. Freshwater doesn’t contain much salt. Saltwater is the salty water of the oceans and brackish water is the water that is a mix of freshwater and saltwater generally found where freshwater and saltwater meet, in estuaries, for example.

Here are some more factors that affect where fish will live…


Fish cannot live in any water without oxygen. However, some fish can live in water that would cause other fish to die. Plants tend to add oxygen to any water body. If there are a lot of plants and or the water is moving about, oxygen levels are more likely to be higher.

On the other hand, decaying plants tend to take oxygen from the water because they use oxygen to decay. The dumping of chemicals into water will also reduce oxygen levels as many chemicals trap oxygen and take it out of the natural ecosystem. Similarly, heated water from thermal pollution also causes oxygen reduction. As you can see, it is not that pollution and chemicals cause fish to die because the water is dirty, pollution often results in a reduction of oxygen that literally suffocates fish.


The amount and type of food available will greatly influence the type and amount of fish in any body of water. if there is plenty to eat, there will be plenty of fish that like to eat it around. Competition is also a big factor.


Each species of fish has a specific water temperature range in which it can survive. This varies from species to species. For example, Trout require much colder water than most and that is why you will find some of the best Trout fishing in Australia in Tasmania or higher areas of the Australian Alps. If fish can’t find the exact water temperature they want, they will head to the closest temperature available.


Fish want cover because they are looking for protection from their prey and they are looking to hide themselves from their own prey.

Like us, fish need food, good water, oxygen and shelter. Think about these factors when you are out on your kayak or looking around a body of water for where the fish will be biting. The best fishing spots accommodate the fish they host.


Do you have anything you would like to add to this article? Share your experience through the comments section below.

Robert M Davies
Robert M Davies

Robert passed the "Obsessed With Fishing Test" with flying colours. Instead of talking, Robert has turned his hand to writing about his experience in fishing all around Australia.