Fishing is one of the most popular recreational pursuits in North America. The U.S. Fish & Wildlife Service says around 40 million people fish each year. Fishing can be an ideal way to spend time in the great outdoors, and people often bond with family and friends while fishing.

As any angler can attest, there’s a rush that comes from getting a small tug on the line and then reeling in a fish. At this point, fishermen must decide if the fish is a keeper or should be tossed back into the water. Sometimes the answer is very clear. Rivers and lakes across the world are managed by various organizations that serve to protect wildlife and natural resources. Rules may be in place regarding the sizes of fish that can be kept, which species are safe and which are protected, and even when people can fish.

In a study led by researchers with the U.S. Geological Survey that was published in the journal Fisheries, thousands of distinct populations of fish were studied. Researchers determined that as many as four out of 10 freshwater species in North America are in danger of approaching extinction. As a result, fishing is regulated by Fish and Wildlife officers and game wardens.

Those who are new to fishing or to a particular region must learn and follow the rules regarding fishing. Fishing licenses are typically required to fish in a given state or area. Always speak with a licensing agency about size restrictions and any other rules regarding species of fish. Also learn about which methods of fishing are legal. Drag nets or other methods of mass fish collection or luring the fish with lights or other equipment may be prohibited.

Learning how to safely catch and release fish if the need arises also is an essential component of responsible fishing. When done correctly, catch-and-release methods can ensure high survival rates and preserve native fish populations. The National Park Service advises those who fish to follow these tips.

Avoid fishing when conditions are stressful for fish, such as when water temperatures are high.

Use equipment that enables one to land the fish quickly without struggle.

Avoid the use of scents and artificial baits that encourage fish to swallow hooks. Learn which bait are prohibited in certain bodies of water. Artificial lures that hook the fish in the lip are preferred.

Avoid playing with the fish to exhaustion.

Keep the fish wet and calm, and treat it gently to remove the hook. Hold the fish underwater and allow it to ventilate before release so it can regain its swimming strength.

Fishing is a popular sport and can be enjoyed responsibly. Learn more about fishing regulations at www.nps.gov/subjects/fishing/index.